Merge main into the branch

Co-Authored-By: Claude Opus 5.5 <[email protected]>

.claude/skills/vanilla-parity/SKILL.md

@@ -0,0 +1,76 @@
+---
+name: vanilla-parity
+description: Fix a Horizon bug or gap so it behaves 1:1 like vanilla 26.3, starting from the port ledger (tools/port_ledger.py) instead of grepping. Use for any issue, Discord report or PR that makes Horizon match vanilla: "X doesn't work like in Java", a missing sound, particle, animation, mob behaviour, block rule, screen or packet.
+---
+
+# Vanilla parity with the port ledger
+
+The port ledger pairs every vanilla method with the Rust fn that ports it (or says it is missing, or needs
+no port) and lists where a port isn't wired like vanilla. Ask it first; grep only for what it can't answer.
+Full reference: `docs/port-ledger.md`.
+
+## 0. Have a fresh ledger
+
+```sh
+python3 tools/port_ledger.py build          # ~20 s; again after pulling main
+```
+
+It needs the vanilla jar (the launcher's `versions/26.3/26.3.jar`, or `--jar`) and/or the lab's decompiled
+sources (`python3 tools/lab.py decompile`, or `--sources DIR`). If `build` says it has no vanilla code, run
+the lab first; don't guess vanilla from memory.
+
+## 1. From the report to the code
+
+```sh
+python3 tools/port_ledger.py issue 3236                      # a GitHub issue number
+python3 tools/port_ledger.py issue "mooshroom stays red after lightning"   # or the report's text
+```
+
+It ranks the vanilla classes the report names and lists, per class, its Rust home files, where each method is
+ported, and the known gaps (`missing` rows from the verdict map, seam/client/drift gaps). Often the cause is
+already written there ("Type is not saved"). Then drill in:
+
+```sh
+python3 tools/port_ledger.py where MushroomCow.readAdditionalSaveData   # ports, callers, callees, gaps
+python3 tools/port_ledger.py class MushroomCow                          # every method: where, or missing
+python3 tools/port_ledger.py what crates/horizon-client/src/mobs/farm.rs:120   # which vanilla method a fn ports
+```
+
+A ledger answer is a lead, not a verdict: about 1 in 12 map rows is wrong. Read the vanilla method (path and
+line are in the output) and the Rust fn before changing anything.
+
+## 2. Port it the vanilla way
+
+- Translate the vanilla method, don't reinvent it: same order of operations, same constants, the same random
+  draws in the same order (`horizon_core::random`), Java `Math` through `horizon_core::jmath`.
+- Open the fn's doc with the vanilla method it ports: `` /// `MushroomCow.readAdditionalSaveData`: ... ``.
+  That one line is what makes the next agent find it.
+- Fix the path players run: single player is a client of the integrated server, so server logic lives in
+  `game/lan*.rs` and `src/lan/`, and what only the client's copy shows (particles, local sounds, hand
+  animation) must be reached from `game/remote*.rs`. A fix on the old in-frame path alone fixes nothing.
+- Look at the neighbours the ledger lists for the same class: a `client` or `seam` gap next to your fix is
+  usually the same bug on the other path.
+
+## 3. Before the PR
+
+```sh
+python3 tools/port_ledger.py check --base origin/main
+```
+
+It lists the ports your branch touches with their open gaps, citations to add, stale citations, and (against
+the base) the gaps the branch closes and opens. Close what belongs to your fix, cite what you ported, leave
+no new stale citation. If you ported a method the verdict map called `missing`, change its row in
+`tools/port_map/*.tsv` to `port` with the fn (`file.rs::Owner::fn`) and run
+`python3 tools/port_ledger.py map-check tools/port_map/<file>.tsv`.
+
+Then the usual: the harness for the area (`docs/architecture.md`), `cargo check`/tests per `AGENTS.md`, and
+a small PR that says which vanilla method it now matches.
+
+## Finding work
+
+```sh
+python3 tools/port_ledger.py gaps --kind seam      # ported on two paths, wired on one: the best leads
+python3 tools/port_ledger.py gaps --kind client    # client-only effects the server path never reaches
+python3 tools/port_ledger.py gaps --kind drift     # a port missing a sound, particle, item or constant
+rg -n "player:" tools/port_map/*.tsv               # missing behaviour a player would see
+```

.githooks/pre-commit

@@ -1,2 +1,11 @@
 #!/bin/sh
-exec python3 tools/check_public_tree.py
+# Git for Windows puts a `python3` on PATH that is only the Microsoft Store
+# stub: it prints "Python" and exits non-zero, so the hook fails with no other
+# output. Use the first name that actually runs Python 3.
+for py in python3 python py; do
+    if "$py" -c "import sys; sys.exit(sys.version_info < (3,))" >/dev/null 2>&1; then
+        exec "$py" tools/check_public_tree.py
+    fi
+done
+echo "check_public_tree: no working Python 3 found" >&2
+exit 1

.githooks/pre-push

@@ -1,2 +1,11 @@
 #!/bin/sh
-exec python3 tools/check_public_tree.py --pre-push
+# Git for Windows puts a `python3` on PATH that is only the Microsoft Store
+# stub: it prints "Python" and exits non-zero, so the hook fails with no other
+# output. Use the first name that actually runs Python 3.
+for py in python3 python py; do
+    if "$py" -c "import sys; sys.exit(sys.version_info < (3,))" >/dev/null 2>&1; then
+        exec "$py" tools/check_public_tree.py --pre-push
+    fi
+done
+echo "check_public_tree: no working Python 3 found" >&2
+exit 1

.github/trusted-reviewers.txt

@@ -0,0 +1,9 @@
+# Trusted reviewers: one list for two things (docs/release-flow.md "Trusted reviewers").
+# - `/nightly 2640 2642` picks the pull requests the Nightly holds (tools/ci/nightly_set.py);
+# - `/close`, `/reopen`, `/label`, `/unlabel` triage issues and pull requests (tools/ci/triage_command.py).
+# Ludovic is always allowed and isn't listed. One GitHub login per line, with who added it and when. Removing a
+# line revokes that login at once. A line with only `paused` stops both for every reviewer (Ludovic's still work).
+kacpherek    # added by Ludovic, 2026-10-27
+rdbtCVS      # added by Ludovic, 2026-10-27
+Online5277   # added by Ludovic, 2026-10-27 (his top three by merged pull requests)
+levzzz5154   # added by Ludovic, 2026-10-28 (Horizon Team; author of horizon-mixins)

.github/workflows/cancel-on-close.yml

@@ -16,12 +16,14 @@ jobs:
           GH_TOKEN: ${{ github.token }}
           REPO: ${{ github.repository }}
           BRANCH: ${{ github.event.pull_request.head.ref }}
-          SHA: ${{ github.event.pull_request.head.sha }}
+          HEAD_REPO: ${{ github.event.pull_request.head.repo.full_name }}
         run: |
+          # Every head the pull request had, not only its last: a run-parity label added on an older head left that
+          # run queued after the merge (#3104, 2026-10-29). Its branch in its own repository names its runs (another
+          # fork can have a branch of the same name).
           for status in queued in_progress waiting pending requested; do
-            gh run list -R "$REPO" --branch "$BRANCH" --status "$status" --limit 100 \
-              --json databaseId,event,headSha \
-              -q ".[] | select(.event == \"pull_request\" and .headSha == \"$SHA\") | .databaseId"
+            gh api -X GET "repos/$REPO/actions/runs" -f branch="$BRANCH" -f event=pull_request -f status="$status" \
+              -f per_page=100 --jq ".workflow_runs[] | select(.head_repository.full_name == \"$HEAD_REPO\") | .id"
           done | sort -u | while read -r id; do
             gh run cancel -R "$REPO" "$id" || true
           done

.github/workflows/ci.yml

@@ -72,6 +72,9 @@ jobs:
         if: steps.rust.outputs.required != 'false'
         run: |
           cargo +stable test --workspace --lib --bins --tests --features horizon-client/mods,horizon-mods/pack
+          # The full content-root tests (#[ignore]d: minutes each on a laptop). The same build as above; they need the
+          # prepared vanilla data, so without it they pass at once.
+          cargo +stable test --workspace --lib --features horizon-client/mods,horizon-mods/pack mod_content::tests:: -- --ignored
           cargo +stable test --workspace --doc --features horizon-client/mods,horizon-mods/pack
   # The launcher is its own workspace (launcher/Cargo.toml), so verify's cargo runs never build it. A pull request that
   # changes it or a crate it builds is checked here, and so is every push to main: two pull requests can each pass
@@ -144,6 +147,7 @@ jobs:
     with:
       base: ${{ github.event.pull_request.base.sha }}
       head: ${{ github.event.pull_request.head.sha }}
+      full: ${{ contains(github.event.pull_request.labels.*.name, 'full-parity') }}
   # Horizon never downloads the game. These jobs need a self-hosted Linux runner
   # (label horizon-game) holding the maintainer's own copy: the official launcher's
   # game directory in HORIZON_MINECRAFT_DIR and the pinned server jar in

.github/workflows/game-build.yml

@@ -0,0 +1,292 @@
+name: game build
+# Builds the game for every platform from `ref`: the Java exporters, then Linux and the Linux server and Windows on
+# GitHub, macOS on the Mac mini's runner with a 1500-frame offscreen run of a new world (smoke-test.json). Called by
+# release.yml (the releases) and nightly-build.yml (the opt-in Nightly), always from main's copy of this file: the
+# caller's commit, never the one being built. It holds no secrets: signing the checksums is the callers' own job,
+# which never runs what this one built. See docs/release-flow.md.
+on:
+  workflow_call:
+    inputs:
+      ref:
+        description: The commit to build
+        type: string
+        required: true
+      version:
+        description: The version built in (HORIZON_VERSION), e.g. 0.2.81 or nightly-2026-10-28
+        type: string
+        required: true
+      nightly:
+        description: A nightly's "<date> <short sha>" (HORIZON_NIGHTLY), shown by the game; empty for a release
+        type: string
+        default: ''
+      trusted:
+        # Only release.yml says true: it builds main. A nightly can hold pull requests nobody reviewed yet, whose
+        # build scripts and tests run here and could rewrite target/, the cargo home or a compiler cache. So an
+        # untrusted build never runs on the release runner, never saves the Rust cache (its key is its own anyway),
+        # and a trusted one never reads the machine's shared sccache, which pull requests' jobs write
+        # (tests/test_nightly.py pins all of it).
+        description: The source is main (a release); false for anything else (a nightly)
+        type: boolean
+        default: false
+      developer_id:
+        description: Sign the macOS programs with Developer ID and notarize the zip (the runner's keychain)
+        type: boolean
+        default: true
+permissions:
+  contents: read
+jobs:
+  exporters:
+    # This runner holds the maintainer's own pinned Minecraft jars. Only our classes leave it. An untrusted build
+    # goes to the Mac mini's nightly runner (macOS + horizon-nightly: ludovics-mac-mini-nightly, beside the one that
+    # runs pull requests' parity jobs, so a nightly never waits behind their queue), never the release runner
+    # (MAC_RUNNER: ludovics-mac-mini-release) nor parity-main's.
+    runs-on: ${{ inputs.trusted && vars.MAC_RUNNER || fromJSON('["self-hosted", "macOS", "horizon-nightly"]') }}
+    # Three full preparations (two isolated, one batched) besides the compile.
+    timeout-minutes: 60
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.ref }}
+          persist-credentials: false
+          clean: true
+      - uses: dtolnay/rust-toolchain@stable
+      - run: bash tools/ci/runner-env.sh
+        env:
+          HORIZON_NO_SCCACHE: ${{ inputs.trusted && '1' || '' }}
+      - run: bash tools/ci/vanilla-data.sh
+      - name: Compile and validate original exporters against the pinned jars
+        shell: bash
+        run: |
+          set -euo pipefail
+          # target/ is gone after the clean checkout, and vanilla-data.sh builds the preparer only when it
+          # prepares afresh.
+          cargo build --release --locked -p horizon-prepare
+          # Compiled here, never taken from the runner's shared preparations: pull requests' parity jobs
+          # write those (vanilla-data.sh links .local/exporters to them).
+          rm -rf .local/exporters
+          bundle=$(target/release/horizon-prepare compile-exporters --root "$PWD" | tail -1)
+          mkdir -p exporters
+          cp -R "$bundle/server" "$bundle/client" "$bundle/manifest.json" exporters/
+          # Only our classes and their manifest leave this runner.
+          stray=$(find exporters -type f ! -path exporters/manifest.json \
+            ! \( -name '*.class' \( -path 'exporters/server/dev/horizonlab/parity/*' -o -path 'exporters/client/dev/horizonlab/parity/*' \) \))
+          [ -z "$stray" ] || { echo "::error::not one of our classes: $stray"; exit 1; }
+          python3 tools/check_prepare_exporters.py --binary target/release/horizon-prepare
+      - uses: actions/upload-artifact@v4
+        with:
+          name: original-exporters
+          path: exporters/
+          if-no-files-found: error
+          retention-days: 3
+
+  build:
+    needs: exporters
+    name: build ${{ matrix.name }}
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: linux
+            os: ubuntu-22.04
+            dir: horizon-linux-x86_64
+            asset: horizon-linux-x86_64.tar.gz
+            # The server build too: packaging/server/install.sh installs it on Linux.
+            server_dir: horizon-server-linux-x86_64
+            server_asset: horizon-server-linux-x86_64.tar.gz
+          - name: windows
+            os: windows-latest
+            dir: horizon-windows-x64
+            asset: horizon-windows-x64.zip
+            exe: .exe
+            # The C runtime linked in, so the game runs without the Visual C++ redistributable.
+            rustflags: -C target-feature=+crt-static
+          - name: macos
+            mac: true
+            dir: horizon-macos-arm64
+            asset: horizon-macos-arm64.zip
+    runs-on: ${{ matrix.mac && (inputs.trusted && vars.MAC_RUNNER || fromJSON('["self-hosted", "macOS", "horizon-nightly"]')) || matrix.os }}
+    # Notarizing the zip can take a few minutes.
+    timeout-minutes: ${{ matrix.mac && 60 || 40 }}
+    env:
+      RUSTFLAGS: ${{ matrix.rustflags }}
+      # The release's version, built in (horizon_core::release): --version, user agents, crash reports and
+      # telemetry say it. No version-bump commits.
+      HORIZON_VERSION: ${{ inputs.version }}
+      # A nightly's date and commit ("2026-10-28 0c02067"), which the game shows; empty for a release.
+      HORIZON_NIGHTLY: ${{ inputs.nightly }}
+    defaults:
+      run:
+        shell: bash
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: ${{ inputs.ref }}
+          persist-credentials: false
+          # Always from a clean checkout, the Mac mini's runner too: its work folder is shared with pull requests'
+          # parity jobs, and nothing they leave (target/, an untracked .cargo/config.toml, a build script's output)
+          # may end up in a release. target/ is rebuilt from scratch; .local/ is relinked by vanilla-data.sh, which
+          # keeps its preparations outside the checkout.
+          clean: true
+      - uses: dtolnay/rust-toolchain@stable
+      - uses: Swatinem/rust-cache@v2
+        if: runner.environment == 'github-hosted'
+        with:
+          # A release restores only what a release saved: an untrusted build has its own key and saves nothing.
+          shared-key: ${{ inputs.trusted && 'release' || 'nightly' }}-${{ matrix.name }}
+          save-if: ${{ inputs.trusted }}
+      - name: ALSA and udev headers
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libasound2-dev libudev-dev
+      - name: Build the client, horizon-ctl, horizon-prepare and horizon-server
+        # `horizon-client/mods`: every released game runs code mods (the feature is off in dev builds).
+        run: cargo build --release --locked --features horizon-client/mods -p horizon-client --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
+      - name: Every program the release folder takes was built
+        run: |
+          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
+            test -f "target/release/$binary${{ matrix.exe }}" || { echo "::error::target/release/$binary${{ matrix.exe }} is missing"; exit 1; }
+          done
+      - name: The signing keychain, unlocked
+        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != '' && inputs.developer_id
+        env:
+          MACOS_SIGN_IDENTITY: ${{ vars.MACOS_SIGN_IDENTITY }}
+        run: packaging/macos/keychain.sh unlock
+      - name: Signed with Developer ID and the hardened runtime
+        # Before the checks below, so they run the programs as players will.
+        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != '' && inputs.developer_id
+        env:
+          MACOS_SIGN_IDENTITY: ${{ vars.MACOS_SIGN_IDENTITY }}
+        run: |
+          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
+            codesign --force --options runtime --timestamp --keychain "$MACOS_SIGN_KEYCHAIN" \
+              --identifier "dev.horizon.${binary#horizon-}" --sign "$MACOS_SIGN_IDENTITY" "target/release/$binary"
+            codesign --verify --strict --verbose=2 "target/release/$binary"
+          done
+      - name: Only system libraries
+        # Windows: no non-system DLL (a "DLL not found" dialog on some players' machines). Linux: the standard
+        # loader and libraries every desktop distribution has. macOS: only the system's own libraries.
+        run: |
+          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
+            file="target/release/$binary${{ matrix.exe }}"
+            if [[ "$RUNNER_OS" == macOS ]]; then
+              others=$(otool -L "$file" | tail -n +2 | awk '{print $1}' | grep -v -E '^(/usr/lib/|/System/Library/)' || true)
+              [[ -z "$others" ]] || { echo "::error::$binary links $others"; exit 1; }
+            else
+              ${{ runner.os == 'Windows' && 'python' || 'python3' }} tools/check_imports.py "$file"
+            fi
+          done
+      - name: Every program starts
+        run: |
+          set -euo pipefail
+          bin=target/release
+          "$bin/horizon-client${{ matrix.exe }}" --help | grep -q -- '--resources'
+          "$bin/horizon-ctl${{ matrix.exe }}" --help > /dev/null
+          "$bin/horizon-prepare${{ matrix.exe }}" --help | grep -q -- '--minecraft-dir'
+          # The version is the release's.
+          for binary in horizon-prepare horizon-server; do
+            out=$("$bin/$binary${{ matrix.exe }}" --version | tr -d '\r')
+            echo "$out"
+            [[ "$out" == "$binary $HORIZON_VERSION" ]] || { echo "::error::expected $binary $HORIZON_VERSION"; exit 1; }
+          done
+      - name: Tools from the runner
+        if: runner.environment == 'self-hosted'
+        env:
+          HORIZON_NO_SCCACHE: ${{ inputs.trusted && '1' || '' }}
+        run: bash tools/ci/runner-env.sh
+      - name: Resources prepared from the runner's own Minecraft
+        if: runner.environment == 'self-hosted'
+        run: bash tools/ci/vanilla-data.sh
+      - name: The game runs (offscreen, a new world, 1500 frames)
+        if: runner.environment == 'self-hosted'
+        run: |
+          set -euo pipefail
+          # From a scratch folder: the game keeps its saves and options in the folder it starts in.
+          home="$RUNNER_TEMP/horizon-smoke"
+          rm -rf "$home" && mkdir -p "$home"
+          version=$(sed -n 's/.*"version": *"\([^"]*\)".*/\1/p' research-lock.json | head -1)
+          client="$PWD/target/release/horizon-client"
+          resources="$PWD/.local/horizon-client/$version"
+          (cd "$home" && HORIZON_HOME="$home" HORIZON_NO_AUDIO=1 "$client" --resources "$resources" --offscreen \
+            --world smoke --seed 1 --render-distance 4 --world-frames 1500 --timeout-seconds 180 \
+            --smoke-report "$home/smoke.json" > "$home/client.log" 2>&1) || { tail -40 "$home/client.log"; exit 1; }
+          python3 - "$home/smoke.json" <<'EOF'
+          import json, sys
+          report = json.load(open(sys.argv[1]))
+          print(json.dumps(report))
+          if report.get("error") is not None or report.get("frames", 0) < 1500 or not report.get("chunks") \
+                  or not report.get("meshed_sections") or not report.get("player"):
+              sys.exit("the smoke run did not draw a world")
+          EOF
+          # Published with the release; the publish job checks it again before it publishes anything.
+          cp "$home/smoke.json" "$RUNNER_TEMP/smoke-test.json"
+      - uses: actions/upload-artifact@v4
+        if: runner.environment == 'self-hosted'
+        with:
+          name: smoke-test.json
+          path: ${{ runner.temp }}/smoke-test.json
+          if-no-files-found: error
+          retention-days: 3
+      - uses: actions/download-artifact@v4
+        with:
+          name: original-exporters
+          path: exporters
+      - name: Package
+        run: |
+          set -euo pipefail
+          cargo run --locked -p xtask -- package "target/release/horizon-client${{ matrix.exe }}" "dist/${{ matrix.dir }}"
+          cd dist
+          rm -f "${{ matrix.asset }}"
+          case "${{ matrix.asset }}" in
+            *.tar.gz) tar czf "${{ matrix.asset }}" "${{ matrix.dir }}" ;;
+            *) if [[ "$RUNNER_OS" == Windows ]]; then 7z a -tzip "${{ matrix.asset }}" "${{ matrix.dir }}" > /dev/null
+               else
+                 # Without resource forks and extended attributes: plain ditto adds an
+                 # AppleDouble `._` file beside every file that has any.
+                 ditto -c -k --norsrc --noextattr --noqtn --keepParent "${{ matrix.dir }}" "${{ matrix.asset }}"
+                 if unzip -Z1 "${{ matrix.asset }}" | grep -E '(^|/)(\._|__MACOSX/)'; then
+                   echo "::error::macOS metadata files in ${{ matrix.asset }}"; exit 1
+                 fi
+               fi ;;
+          esac
+          ls -l "${{ matrix.asset }}"
+      - name: Notarized
+        # A zip of programs can't be stapled: Gatekeeper asks Apple the first time each one runs.
+        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != '' && inputs.developer_id
+        run: |
+          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
+            codesign --verify --strict "dist/${{ matrix.dir }}/$binary"
+          done
+          packaging/macos/notarize.sh "dist/${{ matrix.asset }}"
+      - uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.asset }}
+          path: dist/${{ matrix.asset }}
+          if-no-files-found: error
+          retention-days: 3
+      - name: The server build (the game without sound or controllers, as horizon-engine)
+        if: matrix.server_asset
+        run: |
+          set -euo pipefail
+          # After the client is packaged: target/release/horizon-client is rebuilt without the audio and
+          # controllers features, so it needs neither libasound nor libudev (minimal server images lack them),
+          # and with code mods like the client.
+          cargo build --release --locked -p horizon-client --no-default-features --features mods --bin horizon-client
+          cargo run --locked -p xtask -- package-server target/release/horizon-client "dist/${{ matrix.server_dir }}"
+          folder="dist/${{ matrix.server_dir }}"
+          python3 tools/check_imports.py --server "$folder/horizon-engine" "$folder/horizon-server" "$folder/horizon-prepare"
+          "$folder/horizon-engine" --help | grep -q -- '--resources'
+          [[ "$("$folder/horizon-server" --version)" == "horizon-server $HORIZON_VERSION" ]]
+          cd dist
+          rm -f "${{ matrix.server_asset }}"
+          tar czf "${{ matrix.server_asset }}" "${{ matrix.server_dir }}"
+          ls -l "${{ matrix.server_asset }}"
+      - uses: actions/upload-artifact@v4
+        if: matrix.server_asset
+        with:
+          name: ${{ matrix.server_asset }}
+          path: dist/${{ matrix.server_asset }}
+          if-no-files-found: error
+          retention-days: 3
+      - name: The signing keychain, locked again
+        if: always() && runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != '' && inputs.developer_id
+        run: packaging/macos/keychain.sh lock
+

.github/workflows/launcher.yml

@@ -192,9 +192,11 @@ jobs:
           retry "$launcher" install latest
           "$launcher" versions --installed
           "$launcher" links --json
-          clients=("$HORIZON_LAUNCHER_HOME"/versions/v*/horizon-client*)
+          # `install latest` is the Nightly since #3342 (versions/nightly-<date>-<commit>), a vX.Y.Z before.
+          clients=("$HORIZON_LAUNCHER_HOME"/versions/*/horizon-client*)
           client="${clients[0]}"
           echo "installed client: $client"
+          [[ -f "$client" ]] || { echo "::error::no game installed under versions/"; exit 1; }
           # The game's Linux build is the game's to keep portable (release.yml checks it): a
           # release linked to a Nix store is a warning here, not a broken launcher.
           soft() { if [[ "$RUNNER_OS" == "Linux" ]]; then "$@" || echo "::warning::$* failed"; else "$@"; fi; }

.github/workflows/nightly-build.yml

@@ -0,0 +1,278 @@
+name: nightly build
+run-name: nightly build${{ inputs.request && format(' (request {0})', inputs.request) || '' }}
+# The Nightly, the only build Horizon ships since 2026-10-28 (docs/release-flow.md "Nightly"; Ludovic). When the batch
+# train decides (release.yml, with the commit as `base`), once a night, and when a trusted
+# reviewer asks (`/nightly 2640 2642`, nightly-command.yml), it builds main plus the pull requests the reviewers
+# picked, merged in order (tools/ci/nightly_set.py), or main alone with none picked. Main is its newest commit where
+# checks and parity-main passed (or the `base` input), as for a release, and no Nightly is published while a
+# release-blocker is open. It publishes the result as the `nightly` pre-release, which every launcher and
+# `horizon-server update` install. The previous nightly stays a week as nightly-<date>.
+#
+# Why the signing key never meets the pull requests' code:
+# - `pick` merges the picked heads onto main with `git merge-tree --write-tree`: git objects only, no working tree,
+#   so none of their files reaches the disk and no hook, filter or script of theirs runs. It refuses any pull
+#   request that changes a path CODEOWNERS gives to Ludovic (this folder, tools/ci/, the signing and update code),
+#   pushes the merge as nightly/build-<date>-<n> and saves the set on the nightly-state branch.
+# - This file, game-build.yml and every script below run from main's copy: a schedule runs the default branch, and
+#   `uses: ./…` takes the caller's commit. A picked pull request's own .github/ is never read.
+# - `build` (game-build.yml, `trusted: false`) never reaches a release's tools: its macOS jobs run on the runner
+#   that already runs pull requests' parity jobs, never the release runner; its Rust cache has its own key and is
+#   never saved; and releases don't read the machine's shared sccache.
+# - `build` (game-build.yml) checks out and compiles the merge with no secrets: its token reads contents only and
+#   isn't kept in the checkout; the macOS programs are signed ad hoc (Developer ID needs the runner's keychain,
+#   which stays locked for nightlies).
+# - `sign` is the only job with RELEASE_SIGNING_KEY. It checks out nothing but main's tools/ci/sign_release.sh, which
+#   runs the runner's sha256sum and OpenSSL over the archives: it hashes them, never runs them. The signed message
+#   names the channel ("horizon release nightly"), so a nightly's signature can't pass for a release's.
+# - `publish` verifies the signature with main's horizon-release-sign, checks the smoke test, and only then moves
+#   the tag. Like sign, it never executes what build produced.
+# - The source ships with the build: `pick` writes horizon-source.tar.gz with `git archive` (git objects again, nothing
+#   run), `sign` signs it with the builds, and `publish` attaches it and tags the commit nightly-source/<date>-<short>
+#   for good (the dated release and the build branch go after 7 days; native mods pin the commit: docs/native-mods.md).
+#   gh workflow run "nightly build"                     # now (skips when the pick is the same commit as last night's)
+#   gh workflow run "nightly build" -f force=true       # build and publish even if unchanged
+#   gh workflow run "nightly build" -f dry_run=true     # build and sign with a throwaway key, publish nothing
+on:
+  schedule:
+    - cron: '17 20 * * *'  # 20:17 UTC: after the day's waves, before the 03:07 Paris parity audit takes the Mac mini
+  workflow_dispatch:
+    inputs:
+      force:
+        description: Build and publish even if tonight's pick is the commit already published
+        type: boolean
+        default: false
+      dry_run:
+        description: Build and sign with a throwaway key, publish nothing
+        type: boolean
+        default: false
+      issue:
+        description: The issue or pull request whose `/nightly` comment asked for this build (answered there)
+        type: string
+        default: ''
+      request:
+        description: The command's id, in the run's name so it can link the run
+        type: string
+        default: ''
+      prs:
+        description: A dry run's own set, `2640@<head> 2642@<head>` (the saved set stays)
+        type: string
+        default: ''
+      base:
+        description: The commit of main to build on (default main's newest with green checks and parity-main)
+        type: string
+        default: ''
+      urgent:
+        description: Past the day's cap of 12 builds (the train, for a release-now pull request or a forced run)
+        type: boolean
+        default: false
+permissions:
+  contents: read
+concurrency:
+  # One build at a time. A newer request replaces one still waiting: it builds the set as it is by then, so no pick
+  # is lost.
+  group: nightly-build
+  cancel-in-progress: false
+jobs:
+  pick:
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    permissions:
+      contents: write       # nightly/build-<date>-<n> and the nightly-state branch (main is protected)
+      issues: write         # says in the thread when the picked pull requests conflict
+      pull-requests: write
+      actions: read         # main's newest green checks and parity-main runs (the base)
+    outputs:
+      build: ${{ steps.pick.outputs.build }}
+      sha: ${{ steps.pick.outputs.sha }}
+      short: ${{ steps.pick.outputs.short }}
+      source: ${{ steps.pick.outputs.source }}
+      date: ${{ steps.pick.outputs.date }}
+      version: ${{ steps.pick.outputs.version }}
+      nightly: ${{ steps.pick.outputs.nightly }}
+      source_tag: ${{ steps.pick.outputs.source_tag }}
+      dry_run: ${{ steps.mode.outputs.dry_run }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+          persist-credentials: false
+      - id: mode
+        # A dry run never publishes; a hand-started run off main is always one.
+        run: echo "dry_run=${{ github.event_name == 'workflow_dispatch' && (inputs.dry_run || github.ref != 'refs/heads/main') }}" >> "$GITHUB_OUTPUT"
+      - id: pick
+        env:
+          GH_TOKEN: ${{ github.token }}
+          FORCE: ${{ (inputs.force || steps.mode.outputs.dry_run == 'true') && 'yes' || '' }}
+          DRY_RUN: ${{ steps.mode.outputs.dry_run }}
+          NIGHTLY_ISSUE: ${{ inputs.issue }}
+          NIGHTLY_PRS: ${{ inputs.prs }}
+          NIGHTLY_BASE: ${{ inputs.base }}
+          NIGHTLY_URGENT: ${{ inputs.urgent }}
+        run: |
+          python3 tools/ci/nightly.py pick ${FORCE:+--force} | tee -a "$GITHUB_STEP_SUMMARY"
+          { echo; cat nightly-notes.md; } >> "$GITHUB_STEP_SUMMARY"
+      - name: Old nightly/build-* branches deleted (scheduled runs only)
+        # Ludovic, 2026-10-27: older than 7 days, but never the newest build or one a published nightly points to;
+        # nothing but nightly/build-* (nightly.py stale_builds, tests/test_nightly.py).
+        if: github.event_name == 'schedule'
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: |
+          { echo "### nightly/build-* branches"; python3 tools/ci/nightly.py prune-builds --days 7; } | tee -a "$GITHUB_STEP_SUMMARY"
+      - name: The source of the build (horizon-source.tar.gz)
+        if: steps.pick.outputs.build == 'true'
+        env:
+          SHA: ${{ steps.pick.outputs.sha }}
+        run: git archive --format=tar.gz --prefix="horizon-${SHA:0:7}/" -o horizon-source.tar.gz "$SHA"
+      - uses: actions/upload-artifact@v4
+        if: steps.pick.outputs.build == 'true'
+        with:
+          name: horizon-source
+          path: horizon-source.tar.gz
+          if-no-files-found: error
+          retention-days: 3
+      - uses: actions/upload-artifact@v4
+        with:
+          name: nightly-notes
+          path: nightly-notes.md
+          retention-days: 3
+
+  build:
+    needs: pick
+    if: needs.pick.outputs.build == 'true'
+    uses: ./.github/workflows/game-build.yml
+    with:
+      ref: ${{ needs.pick.outputs.sha }}
+      version: ${{ needs.pick.outputs.version }}
+      nightly: ${{ needs.pick.outputs.nightly }}
+      developer_id: false
+      trusted: false  # it can hold unreviewed pull requests: their own cache key, never saved, not the release runner
+
+  sign:
+    needs: [pick, build]
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    # The key's only job: main's sign_release.sh hashes the archives and signs with the runner's OpenSSL.
+    environment: ${{ needs.pick.outputs.dry_run != 'true' && 'release' || '' }}
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          sparse-checkout: tools/ci/sign_release.sh
+          sparse-checkout-cone-mode: false
+          persist-credentials: false
+      - uses: actions/download-artifact@v4
+        with:
+          path: dist
+          pattern: horizon-*
+          merge-multiple: true
+      - name: Sign the checksums (SHA256SUMS, SHA256SUMS.sig) for the nightly channel
+        env:
+          RELEASE_SIGNING_KEY: ${{ secrets.RELEASE_SIGNING_KEY }}
+          RELEASE_SIGNING_KEY_NEXT: ${{ secrets.RELEASE_SIGNING_KEY_NEXT }}
+          EPHEMERAL: ${{ needs.pick.outputs.dry_run == 'true' && 'yes' || '' }}
+        run: |
+          bash tools/ci/sign_release.sh nightly dist/horizon-linux-x86_64.tar.gz dist/horizon-windows-x64.zip \
+            dist/horizon-macos-arm64.zip dist/horizon-server-linux-x86_64.tar.gz dist/horizon-source.tar.gz
+      - uses: actions/upload-artifact@v4
+        with:
+          name: signature
+          path: dist/SHA256SUMS*
+          if-no-files-found: error
+          retention-days: 3
+      - uses: actions/upload-artifact@v4
+        if: needs.pick.outputs.dry_run == 'true'
+        with:
+          name: ephemeral.pub
+          path: dist/ephemeral.pub
+          retention-days: 3
+
+  publish:
+    needs: [pick, build, sign]
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    permissions:
+      contents: write
+      issues: read          # the open release-blocker issues (gate)
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          persist-credentials: false
+      - uses: actions/download-artifact@v4
+        with:
+          path: dist
+          merge-multiple: true
+      - name: The signature, checked as launchers check it
+        env:
+          EPHEMERAL: ${{ needs.pick.outputs.dry_run == 'true' && 'yes' || '' }}
+        run: |
+          key=(); [[ -n "$EPHEMERAL" ]] && key=(--key "$(cat dist/ephemeral.pub)")
+          cargo run --locked --quiet -p horizon-release-sign -- verify --tag nightly --publishing "${key[@]}" dist
+      - name: Ready to publish (the smoke test drew a world, no release-blocker is open)
+        # Right before publishing, as for a release: an issue labelled while the builds ran still holds it. A dry run
+        # only reports what a real run would do (that is how a blocker's fix is tried).
+        env:
+          GH_TOKEN: ${{ github.token }}
+          DRY_RUN: ${{ needs.pick.outputs.dry_run }}
+        run: |
+          if ! python3 tools/release_train.py gate --kind game --smoke dist/smoke-test.json --blockers; then
+            [[ "$DRY_RUN" == true ]] || { echo "::error::Nothing published"; exit 1; }
+            echo "::warning::A real run would publish nothing"
+          fi
+      - name: Publish as the `nightly` pre-release
+        if: needs.pick.outputs.dry_run != 'true'
+        env:
+          GH_TOKEN: ${{ github.token }}
+          SHA: ${{ needs.pick.outputs.sha }}
+          DATE: ${{ needs.pick.outputs.date }}
+          SOURCE_TAG: ${{ needs.pick.outputs.source_tag }}
+        run: |
+          set -euo pipefail
+          python3 tools/ci/nightly.py rotate
+          signature=(); [[ -f dist/SHA256SUMS.sig ]] && signature=(dist/SHA256SUMS.sig)
+          # A pre-release, never GitHub's latest: the latest stays the last vX.Y.Z, which launchers and servers from
+          # before the Nightly-only switch keep (they don't read Nightlies).
+          gh release create nightly --prerelease --latest=false --target "$SHA" \
+            --title "Nightly $DATE · ${SHA:0:7}" --notes-file dist/nightly-notes.md \
+            "dist/horizon-linux-x86_64.tar.gz#Nightly game files: Linux (horizon-linux-x86_64.tar.gz)" \
+            "dist/horizon-windows-x64.zip#Nightly game files: Windows (horizon-windows-x64.zip)" \
+            "dist/horizon-macos-arm64.zip#Nightly game files: macOS (horizon-macos-arm64.zip)" \
+            "dist/horizon-server-linux-x86_64.tar.gz#Nightly dedicated server for Linux (horizon-server-linux-x86_64.tar.gz)" \
+            "dist/horizon-source.tar.gz#Source of this Nightly, commit ${SHA:0:7} (horizon-source.tar.gz; kept for good as the tag $SOURCE_TAG)" \
+            dist/SHA256SUMS "${signature[@]}" dist/smoke-test.json
+          python3 tools/ci/nightly.py keep-source "$SHA" "$DATE"
+          python3 tools/ci/nightly.py prune --days 7
+      - name: Dry run, the nightly that would be published
+        if: needs.pick.outputs.dry_run == 'true'
+        run: |
+          echo "Would publish nightly at ${{ needs.pick.outputs.sha }} (${{ needs.pick.outputs.source }})"
+          ls -l dist
+
+  answer:
+    # Tells the thread that asked for this build how it ended. A conflict `pick` already explained there.
+    needs: [pick, build, sign, publish]
+    if: always() && inputs.issue != '' && needs.pick.result == 'success'
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    permissions:
+      issues: write
+      pull-requests: write
+    steps:
+      - env:
+          GH_TOKEN: ${{ github.token }}
+          ISSUE: ${{ inputs.issue }}
+          BUILD: ${{ needs.pick.outputs.build }}
+          PUBLISHED: ${{ needs.publish.result }}
+          DRY_RUN: ${{ needs.pick.outputs.dry_run }}
+          NAME: Nightly ${{ needs.pick.outputs.date }} · ${{ needs.pick.outputs.short }}
+          RUN: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
+        run: |
+          if [[ "$BUILD" != true ]]; then
+            text="nothing new: the published Nightly is already this build."
+          elif [[ "$PUBLISHED" == success && "$DRY_RUN" == true ]]; then
+            text="the dry run built and signed $NAME; nothing was published. $RUN"
+          elif [[ "$PUBLISHED" == success ]]; then
+            text="published $NAME: https://github.com/$GITHUB_REPOSITORY/releases/tag/nightly. Launchers install it at their next check."
+          else
+            text="the build failed, nothing was published: $RUN"
+          fi
+          gh api "repos/$GITHUB_REPOSITORY/issues/$ISSUE/comments" -f body="🤖 Nightly: $text"

.github/workflows/nightly-command.yml

@@ -0,0 +1,46 @@
+name: nightly command
+# `/nightly …` comments: the trusted reviewers in .github/trusted-reviewers.txt (and Ludovic) pick the pull requests
+# the Nightly holds (docs/release-flow.md "Nightly channel", tools/ci/nightly_set.py). This job only checks who asked,
+# saves the set on the nightly-state branch, starts `nightly build` and answers in the thread.
+#
+# Why no pull request's code runs here, though the token can write:
+# - `issue_comment` always runs this file from main, whoever comments and wherever; a pull request's own copy of it
+#   is never read.
+# - It checks out main and runs main's nightly_set.py. The comment's text and author reach it as env vars, never in
+#   a shell line.
+# - It never checks out, fetches or merges a pull request: it reads their file lists through the API. The merge
+#   happens in nightly-build.yml's `pick`, with git objects only; their code runs in its `build`, without secrets.
+on:
+  issue_comment:
+    types: [created]
+permissions:
+  contents: read
+jobs:
+  command:
+    # Every other comment skips here, before a runner starts.
+    if: startsWith(github.event.comment.body, '/nightly') && github.event.comment.user.type != 'Bot'
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    permissions:
+      contents: write       # the nightly-state branch (main is protected)
+      actions: write        # starts `nightly build`
+      issues: write         # answers in the thread
+      pull-requests: write
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: main
+          persist-credentials: false
+          sparse-checkout: |
+            .github/CODEOWNERS
+            .github/trusted-reviewers.txt
+            tools/ci/nightly_set.py
+          sparse-checkout-cone-mode: false
+      - name: Run the command
+        env:
+          GH_TOKEN: ${{ github.token }}
+          BODY: ${{ github.event.comment.body }}
+          AUTHOR: ${{ github.event.comment.user.login }}
+          ISSUE: ${{ github.event.issue.number }}
+          COMMENT_URL: ${{ github.event.comment.html_url }}
+        run: python3 tools/ci/nightly_set.py command

.github/workflows/parity-main.yml

@@ -25,8 +25,8 @@ jobs:
   parity-main:
     # A Mac mini runner of its own (ludovics-mac-mini-2 holds only this label since 2026-10-26): behind PR parity jobs
     # this run waited 2 h while every merge replaced the pending one, and on the release runner a release then waited
-    # behind the next run. PR parity jobs have ludovics-mac-mini and the desktop. Not the desktop: a job slowed down
-    # because the maintainer came back could time out, and a failure here bisects and comments on merges.
+    # behind the next run. PR parity jobs have ludovics-mac-mini and playhorizon. Not playhorizon: its 4 CPUs
+    # make a core-crate run several times longer, and a failure here bisects and comments on merges.
     runs-on: [self-hosted, macOS, horizon-parity-main]
     timeout-minutes: 240  # a core-crate batch reruns ~300 harnesses (~60-90 min), a bisect a few rounds of the failures
     steps:

.github/workflows/parity.yml

@@ -1,6 +1,6 @@
 name: parity
-# The vanilla harnesses a pull request's changes can affect, on the Mac mini's runner, which holds the maintainer's
-# own Minecraft files (Horizon never downloads the game). Called by ci.yml for pull requests from this repository
+# The vanilla harnesses a pull request's changes can affect, on the Mac mini's runner or playhorizon's, which hold the
+# maintainer's own Minecraft files (Horizon never downloads the game). Called by ci.yml for pull requests from this repository
 # and by run-parity.yml when a maintainer labels a fork's pull request run-parity. See docs/release-flow.md.
 on:
   workflow_call:
@@ -13,6 +13,13 @@ on:
         description: The commit to check out and test
         type: string
         required: true
+      full:
+        description: >-
+          The pull request carries the full-parity label (a change every harness reaches, such as a crate split): it
+          runs on playhorizon's runner only, so the Mac mini's runners stay free for the others. While that runner is
+          busy the job waits for it.
+        type: boolean
+        default: false
 permissions:
   contents: read
 env:
@@ -21,8 +28,10 @@ env:
 
 jobs:
   parity:
-    runs-on: [self-hosted, horizon-game]
-    timeout-minutes: 120  # a change to core crates reruns ~300 harnesses: ~60-90 min on the Mac mini
+    runs-on: ${{ inputs.full && fromJSON('["self-hosted", "horizon-game", "playhorizon"]') || fromJSON('["self-hosted", "horizon-game"]') }}
+    # A change to core crates reruns ~350 harnesses: ~60-90 min on the Mac mini; on playhorizon (4 of its 8 vCPUs, 4
+    # harnesses at a time) up to a few hours, and any pull request's job may land there.
+    timeout-minutes: ${{ inputs.full && 360 || 180 }}
     steps:
       - uses: actions/checkout@v4
         with:

.github/workflows/release.yml

@@ -1,22 +1,15 @@
 name: release
-# Automatic game releases (docs/release-flow.md). After every green `checks` run on main, every 10 minutes (so a
-# release waiting for merges to settle goes out without another merge) and by hand, tools/release_train.py decides,
-# for a commit whose checks and parity-main (the vanilla harnesses on main) both passed:
-# a release when 5 pull requests merged since the last one changed what players run and the newest merged 5 minutes
-# ago, or when the oldest has waited 6 hours, or at once for a pull request labelled release-now.
-# RELEASES_PAUSED=1 (repository variable) stops them; so does an open issue labelled release-blocker, forced runs too.
-# Builds Linux (an older Ubuntu, so the binary runs on any recent distribution and on NixOS through nix-ld) and
-# Windows on GitHub, macOS on the Mac mini's runner (MAC_RUNNER=macos-latest sends it to GitHub), then
-# publishes vX.Y.Z on the release line in .github/release-line.txt (docs/versioning.md; without it, the dated
-# vYYYY.MM.DD[.N] from before 0.2) with notes from the merged pull requests, as the release and GitHub's latest: one
-# channel, which launchers, `horizon-server update` and install.sh follow at once. So it is published only after the
-# checks that used to gate a promotion pass in this run: the Mac mini's smoke test drew a world, and no release-blocker
-# is open (tools/release_train.py gate); otherwise nothing is published. macOS: with the repository variable
-# MACOS_SIGN_IDENTITY set, the programs are signed with
-# Developer ID and the hardened runtime and the zip is notarized, from the runner's signing keychain
-# (packaging/macos/README.md); unset (forks), ad hoc.
-#   gh workflow run release --ref <branch>                       # dry run: builds and notes, publishes nothing
-#   gh workflow run release -f dry_run=false -f force=true       # on main: release now, whatever the rules say
+# Automatic game releases (docs/release-flow.md). Horizon ships only the Nightly since 2026-10-28 (Ludovic): this
+# workflow is the batch train that decides when a new Nightly goes out, and `nightly build` (nightly-build.yml) builds,
+# signs and publishes it. After every green `checks` run on main, every 10 minutes (so a batch waiting for merges to
+# settle goes out without another merge) and by hand, tools/release_train.py decides, for a commit whose checks and
+# parity-main (the vanilla harnesses on main) both passed: a Nightly when 5 pull requests merged since the published
+# Nightly changed what players run and the newest merged 5 minutes ago, or when the oldest has waited 6 hours, or at
+# once for a pull request labelled release-now. RELEASES_PAUSED=1 (repository variable) stops it; so does an open issue
+# labelled release-blocker, forced runs too (nightly-build.yml checks again before publishing). One Nightly build at a
+# time, at most 12 a day (release-now and force=true pass the cap). No `vX.Y.Z` game release is made any more.
+#   gh workflow run release --ref <branch>                       # dry run: decides, starts nothing
+#   gh workflow run release -f dry_run=false -f force=true       # on main: a Nightly now, whatever the rules say
 on:
   workflow_run:
     # A game release ships a commit both passed on (parity-main runs on batches: the newest commit it passed on).
@@ -28,19 +21,24 @@ on:
   workflow_dispatch:
     inputs:
       dry_run:
-        description: Build everything and write the notes, but publish nothing
+        description: Decide only; start no Nightly build
         type: boolean
         default: true
       force:
-        description: Release even without player-facing changes, before merges settle or while paused
+        description: A Nightly even without player-facing changes, before merges settle, while paused or past the day's cap
         type: boolean
         default: false
 permissions:
   contents: read
   # The open release-blocker issues (decide).
   issues: read
+  # The checks, parity-main and nightly build runs (decide).
+  actions: read
 concurrency:
-  group: game-release
+  # One release at a time. A hand-started dry run publishes nothing, so it can't race a real release: it gets a
+  # group of its own. In the shared group, a release queued behind it replaced it as the pending run and GitHub
+  # cancelled it (#2779's dry run, 2026-10-27), which happens all day while releases go out in batches.
+  group: game-release${{ github.event_name == 'workflow_dispatch' && inputs.dry_run && '-dry-run' || '' }}
   cancel-in-progress: false
 jobs:
   decide:
@@ -51,9 +49,8 @@ jobs:
     timeout-minutes: 10
     outputs:
       release: ${{ steps.decide.outputs.release }}
-      tag: ${{ steps.decide.outputs.tag }}
-      version: ${{ steps.decide.outputs.version }}
       head: ${{ steps.decide.outputs.head }}
+      urgent: ${{ steps.decide.outputs.urgent }}
       dry_run: ${{ steps.mode.outputs.dry_run }}
     steps:
       - uses: actions/checkout@v4
@@ -73,364 +70,21 @@ jobs:
         run: |
           python3 tools/release_train.py decide --kind game ${HEAD_SHA:+--head "$HEAD_SHA"} ${FORCE:+--force} | tee decision.json
           echo "### $(jq -r '.reason' decision.json)" >> "$GITHUB_STEP_SUMMARY"
-          # The version the programs are built with (docs/versioning.md): the tag without its v.
-          tag=$(jq -r '.tag' decision.json)
-          echo "version=${tag#v}" >> "$GITHUB_OUTPUT"
-          # A dry run builds whatever the decision, to test the builds.
-          if [[ "${{ steps.mode.outputs.dry_run }}" == true ]]; then echo "release=true" >> "$GITHUB_OUTPUT"; fi
 
-  exporters:
+  nightly:
+    # The Nightly is the release: nightly-build.yml builds the decided commit plus the reviewers' picks, signs it for
+    # the Nightly channel and publishes it once its smoke test passed and no release-blocker is open.
     needs: decide
-    if: needs.decide.outputs.release == 'true'
-    # This runner holds the maintainer's own pinned Minecraft jars. Only our classes leave it.
-    runs-on: ${{ vars.MAC_RUNNER || 'ludovics-mac-mini' }}
-    # Three full preparations (two isolated, one batched) besides the compile.
-    timeout-minutes: 60
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ needs.decide.outputs.head }}
-          persist-credentials: false
-          clean: true
-      - uses: dtolnay/rust-toolchain@stable
-      - run: bash tools/ci/runner-env.sh
-      - run: bash tools/ci/vanilla-data.sh
-      - name: Compile and validate original exporters against the pinned jars
-        shell: bash
-        run: |
-          set -euo pipefail
-          # target/ is gone after the clean checkout, and vanilla-data.sh builds the preparer only when it
-          # prepares afresh.
-          cargo build --release --locked -p horizon-prepare
-          # Compiled here, never taken from the runner's shared preparations: pull requests' parity jobs
-          # write those (vanilla-data.sh links .local/exporters to them).
-          rm -rf .local/exporters
-          bundle=$(target/release/horizon-prepare compile-exporters --root "$PWD" | tail -1)
-          mkdir -p exporters
-          cp -R "$bundle/server" "$bundle/client" "$bundle/manifest.json" exporters/
-          # Only our classes and their manifest leave this runner.
-          stray=$(find exporters -type f ! -path exporters/manifest.json \
-            ! \( -name '*.class' \( -path 'exporters/server/dev/horizonlab/parity/*' -o -path 'exporters/client/dev/horizonlab/parity/*' \) \))
-          [ -z "$stray" ] || { echo "::error::not one of our classes: $stray"; exit 1; }
-          python3 tools/check_prepare_exporters.py --binary target/release/horizon-prepare
-      - uses: actions/upload-artifact@v4
-        with:
-          name: original-exporters
-          path: exporters/
-          if-no-files-found: error
-          retention-days: 3
-
-  build:
-    needs: [decide, exporters]
-    if: needs.decide.outputs.release == 'true'
-    name: build ${{ matrix.name }}
-    strategy:
-      fail-fast: false
-      matrix:
-        include:
-          - name: linux
-            os: ubuntu-22.04
-            dir: horizon-linux-x86_64
-            asset: horizon-linux-x86_64.tar.gz
-            # The server build too: packaging/server/install.sh installs it on Linux.
-            server_dir: horizon-server-linux-x86_64
-            server_asset: horizon-server-linux-x86_64.tar.gz
-          - name: windows
-            os: windows-latest
-            dir: horizon-windows-x64
-            asset: horizon-windows-x64.zip
-            exe: .exe
-            # The C runtime linked in, so the game runs without the Visual C++ redistributable.
-            rustflags: -C target-feature=+crt-static
-          - name: macos
-            mac: true
-            dir: horizon-macos-arm64
-            asset: horizon-macos-arm64.zip
-    runs-on: ${{ matrix.mac && (vars.MAC_RUNNER || 'ludovics-mac-mini') || matrix.os }}
-    # Notarizing the zip can take a few minutes.
-    timeout-minutes: ${{ matrix.mac && 60 || 40 }}
-    env:
-      RUSTFLAGS: ${{ matrix.rustflags }}
-      # The release's version, built in (horizon_core::release): --version, user agents, crash reports and
-      # telemetry say it. No version-bump commits.
-      HORIZON_VERSION: ${{ needs.decide.outputs.version }}
-    defaults:
-      run:
-        shell: bash
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          ref: ${{ needs.decide.outputs.head }}
-          persist-credentials: false
-          # Always from a clean checkout, the Mac mini's runner too: its work folder is shared with pull requests'
-          # parity jobs, and nothing they leave (target/, an untracked .cargo/config.toml, a build script's output)
-          # may end up in a release. target/ is rebuilt from scratch; .local/ is relinked by vanilla-data.sh, which
-          # keeps its preparations outside the checkout.
-          clean: true
-      - uses: dtolnay/rust-toolchain@stable
-      - uses: Swatinem/rust-cache@v2
-        if: runner.environment == 'github-hosted'
-        with:
-          shared-key: release-${{ matrix.name }}
-      - name: ALSA and udev headers
-        if: runner.os == 'Linux'
-        run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libasound2-dev libudev-dev
-      - name: Build the client, horizon-ctl, horizon-prepare and horizon-server
-        # `horizon-client/mods`: every released game runs code mods (the feature is off in dev builds).
-        run: cargo build --release --locked --features horizon-client/mods -p horizon-client --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
-      - name: Every program the release folder takes was built
-        run: |
-          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
-            test -f "target/release/$binary${{ matrix.exe }}" || { echo "::error::target/release/$binary${{ matrix.exe }} is missing"; exit 1; }
-          done
-      - name: The signing keychain, unlocked
-        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != ''
-        env:
-          MACOS_SIGN_IDENTITY: ${{ vars.MACOS_SIGN_IDENTITY }}
-        run: packaging/macos/keychain.sh unlock
-      - name: Signed with Developer ID and the hardened runtime
-        # Before the checks below, so they run the programs as players will.
-        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != ''
-        env:
-          MACOS_SIGN_IDENTITY: ${{ vars.MACOS_SIGN_IDENTITY }}
-        run: |
-          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
-            codesign --force --options runtime --timestamp --keychain "$MACOS_SIGN_KEYCHAIN" \
-              --identifier "dev.horizon.${binary#horizon-}" --sign "$MACOS_SIGN_IDENTITY" "target/release/$binary"
-            codesign --verify --strict --verbose=2 "target/release/$binary"
-          done
-      - name: Only system libraries
-        # Windows: no non-system DLL (a "DLL not found" dialog on some players' machines). Linux: the standard
-        # loader and libraries every desktop distribution has. macOS: only the system's own libraries.
-        run: |
-          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
-            file="target/release/$binary${{ matrix.exe }}"
-            if [[ "$RUNNER_OS" == macOS ]]; then
-              others=$(otool -L "$file" | tail -n +2 | awk '{print $1}' | grep -v -E '^(/usr/lib/|/System/Library/)' || true)
-              [[ -z "$others" ]] || { echo "::error::$binary links $others"; exit 1; }
-            else
-              ${{ runner.os == 'Windows' && 'python' || 'python3' }} tools/check_imports.py "$file"
-            fi
-          done
-      - name: Every program starts
-        run: |
-          set -euo pipefail
-          bin=target/release
-          "$bin/horizon-client${{ matrix.exe }}" --help | grep -q -- '--resources'
-          "$bin/horizon-ctl${{ matrix.exe }}" --help > /dev/null
-          "$bin/horizon-prepare${{ matrix.exe }}" --help | grep -q -- '--minecraft-dir'
-          # The version is the release's.
-          for binary in horizon-prepare horizon-server; do
-            out=$("$bin/$binary${{ matrix.exe }}" --version | tr -d '\r')
-            echo "$out"
-            [[ "$out" == "$binary $HORIZON_VERSION" ]] || { echo "::error::expected $binary $HORIZON_VERSION"; exit 1; }
-          done
-      - name: Tools from the runner
-        if: runner.environment == 'self-hosted'
-        run: bash tools/ci/runner-env.sh
-      - name: Resources prepared from the runner's own Minecraft
-        if: runner.environment == 'self-hosted'
-        run: bash tools/ci/vanilla-data.sh
-      - name: The game runs (offscreen, a new world, 1500 frames)
-        if: runner.environment == 'self-hosted'
-        run: |
-          set -euo pipefail
-          # From a scratch folder: the game keeps its saves and options in the folder it starts in.
-          home="$RUNNER_TEMP/horizon-smoke"
-          rm -rf "$home" && mkdir -p "$home"
-          version=$(sed -n 's/.*"version": *"\([^"]*\)".*/\1/p' research-lock.json | head -1)
-          client="$PWD/target/release/horizon-client"
-          resources="$PWD/.local/horizon-client/$version"
-          (cd "$home" && HORIZON_HOME="$home" HORIZON_NO_AUDIO=1 "$client" --resources "$resources" --offscreen \
-            --world smoke --seed 1 --render-distance 4 --world-frames 1500 --timeout-seconds 180 \
-            --smoke-report "$home/smoke.json" > "$home/client.log" 2>&1) || { tail -40 "$home/client.log"; exit 1; }
-          python3 - "$home/smoke.json" <<'EOF'
-          import json, sys
-          report = json.load(open(sys.argv[1]))
-          print(json.dumps(report))
-          if report.get("error") is not None or report.get("frames", 0) < 1500 or not report.get("chunks") \
-                  or not report.get("meshed_sections") or not report.get("player"):
-              sys.exit("the smoke run did not draw a world")
-          EOF
-          # Published with the release; the publish job checks it again before it publishes anything.
-          cp "$home/smoke.json" "$RUNNER_TEMP/smoke-test.json"
-      - uses: actions/upload-artifact@v4
-        if: runner.environment == 'self-hosted'
-        with:
-          name: smoke-test.json
-          path: ${{ runner.temp }}/smoke-test.json
-          if-no-files-found: error
-          retention-days: 3
-      - uses: actions/download-artifact@v4
-        with:
-          name: original-exporters
-          path: exporters
-      - name: Package
-        run: |
-          set -euo pipefail
-          cargo run --locked -p xtask -- package "target/release/horizon-client${{ matrix.exe }}" "dist/${{ matrix.dir }}"
-          cd dist
-          rm -f "${{ matrix.asset }}"
-          case "${{ matrix.asset }}" in
-            *.tar.gz) tar czf "${{ matrix.asset }}" "${{ matrix.dir }}" ;;
-            *) if [[ "$RUNNER_OS" == Windows ]]; then 7z a -tzip "${{ matrix.asset }}" "${{ matrix.dir }}" > /dev/null
-               else
-                 # Without resource forks and extended attributes: plain ditto adds an
-                 # AppleDouble `._` file beside every file that has any.
-                 ditto -c -k --norsrc --noextattr --noqtn --keepParent "${{ matrix.dir }}" "${{ matrix.asset }}"
-                 if unzip -Z1 "${{ matrix.asset }}" | grep -E '(^|/)(\._|__MACOSX/)'; then
-                   echo "::error::macOS metadata files in ${{ matrix.asset }}"; exit 1
-                 fi
-               fi ;;
-          esac
-          ls -l "${{ matrix.asset }}"
-      - name: Notarized
-        # A zip of programs can't be stapled: Gatekeeper asks Apple the first time each one runs.
-        if: runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != ''
-        run: |
-          for binary in horizon-client horizon-ctl horizon-prepare horizon-server; do
-            codesign --verify --strict "dist/${{ matrix.dir }}/$binary"
-          done
-          packaging/macos/notarize.sh "dist/${{ matrix.asset }}"
-      - uses: actions/upload-artifact@v4
-        with:
-          name: ${{ matrix.asset }}
-          path: dist/${{ matrix.asset }}
-          if-no-files-found: error
-          retention-days: 3
-      - name: The server build (the game without sound or controllers, as horizon-engine)
-        if: matrix.server_asset
-        run: |
-          set -euo pipefail
-          # After the client is packaged: target/release/horizon-client is rebuilt without the audio and
-          # controllers features, so it needs neither libasound nor libudev (minimal server images lack them),
-          # and with code mods like the client.
-          cargo build --release --locked -p horizon-client --no-default-features --features mods --bin horizon-client
-          cargo run --locked -p xtask -- package-server target/release/horizon-client "dist/${{ matrix.server_dir }}"
-          folder="dist/${{ matrix.server_dir }}"
-          python3 tools/check_imports.py --server "$folder/horizon-engine" "$folder/horizon-server" "$folder/horizon-prepare"
-          "$folder/horizon-engine" --help | grep -q -- '--resources'
-          [[ "$("$folder/horizon-server" --version)" == "horizon-server $HORIZON_VERSION" ]]
-          cd dist
-          rm -f "${{ matrix.server_asset }}"
-          tar czf "${{ matrix.server_asset }}" "${{ matrix.server_dir }}"
-          ls -l "${{ matrix.server_asset }}"
-      - uses: actions/upload-artifact@v4
-        if: matrix.server_asset
-        with:
-          name: ${{ matrix.server_asset }}
-          path: dist/${{ matrix.server_asset }}
-          if-no-files-found: error
-          retention-days: 3
-      - name: The signing keychain, locked again
-        if: always() && runner.os == 'macOS' && vars.MACOS_SIGN_IDENTITY != ''
-        run: packaging/macos/keychain.sh lock
-
-  sign:
-    needs: [decide, build]
+    if: needs.decide.outputs.release == 'true' && needs.decide.outputs.dry_run != 'true'
     runs-on: ubuntu-latest
-    timeout-minutes: 10
-    # The only job that holds the release signing key, a secret of the `release` environment, which only main's real
-    # releases enter (dry runs sign with a throwaway key). It runs no code from the repository but
-    # tools/ci/sign_release.sh, which calls only the runner's sha256sum and OpenSSL (docs/release-flow.md).
-    environment: ${{ needs.decide.outputs.dry_run != 'true' && 'release' || '' }}
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          sparse-checkout: tools/ci/sign_release.sh
-          sparse-checkout-cone-mode: false
-          persist-credentials: false
-      - uses: actions/download-artifact@v4
-        with:
-          path: dist
-          pattern: horizon-*
-          merge-multiple: true
-      - name: Sign the checksums (SHA256SUMS, SHA256SUMS.sig)
-        env:
-          RELEASE_SIGNING_KEY: ${{ secrets.RELEASE_SIGNING_KEY }}
-          RELEASE_SIGNING_KEY_NEXT: ${{ secrets.RELEASE_SIGNING_KEY_NEXT }}
-          EPHEMERAL: ${{ needs.decide.outputs.dry_run == 'true' && 'yes' || '' }}
-          TAG: ${{ needs.decide.outputs.tag }}
-        run: |
-          bash tools/ci/sign_release.sh "$TAG" dist/horizon-linux-x86_64.tar.gz dist/horizon-windows-x64.zip \
-            dist/horizon-macos-arm64.zip dist/horizon-server-linux-x86_64.tar.gz
-      - uses: actions/upload-artifact@v4
-        with:
-          name: signature
-          path: dist/SHA256SUMS*
-          if-no-files-found: error
-          retention-days: 3
-      - uses: actions/upload-artifact@v4
-        if: needs.decide.outputs.dry_run == 'true'
-        with:
-          name: ephemeral.pub
-          path: dist/ephemeral.pub
-          retention-days: 3
-
-  publish:
-    needs: [decide, build, sign]
-    runs-on: ubuntu-latest
-    timeout-minutes: 15
+    timeout-minutes: 5
     permissions:
-      contents: write
-      issues: read
+      actions: write  # starts `nightly build`
     steps:
-      - uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-      - name: Notes
-        env:
+      - env:
           GH_TOKEN: ${{ github.token }}
+          HEAD_SHA: ${{ needs.decide.outputs.head }}
+          URGENT: ${{ needs.decide.outputs.urgent }}
         run: |
-          python3 tools/release_train.py notes --kind game --tag "${{ needs.decide.outputs.tag }}" \
-            --head "${{ needs.decide.outputs.head }}" --out notes > /dev/null
-          { echo "## $(cat notes/title.txt)"; echo; cat notes/body.md; } >> "$GITHUB_STEP_SUMMARY"
-      - uses: actions/download-artifact@v4
-        with:
-          path: dist
-          merge-multiple: true
-      - name: The signature, checked as launchers check it
-        env:
-          TAG: ${{ needs.decide.outputs.tag }}
-          EPHEMERAL: ${{ needs.decide.outputs.dry_run == 'true' && 'yes' || '' }}
-        run: |
-          key=(); [[ -n "$EPHEMERAL" ]] && key=(--key "$(cat dist/ephemeral.pub)")
-          cargo run --locked --quiet -p horizon-release-sign -- verify --tag "$TAG" --publishing "${key[@]}" dist
-      - name: Ready to publish (the smoke test passed, no release-blocker is open)
-        # Right before publishing: an issue labelled while the builds ran still holds this release. A dry run only
-        # reports what a real run would do.
-        env:
-          GH_TOKEN: ${{ github.token }}
-          DRY_RUN: ${{ needs.decide.outputs.dry_run }}
-        run: |
-          if ! python3 tools/release_train.py gate --kind game --smoke dist/smoke-test.json --blockers; then
-            [[ "$DRY_RUN" == true ]] || { echo "::error::Nothing published"; exit 1; }
-            echo "::warning::A real run would publish nothing"
-          fi
-      - name: Publish ${{ needs.decide.outputs.tag }}
-        if: needs.decide.outputs.dry_run != 'true'
-        env:
-          GH_TOKEN: ${{ github.token }}
-          TAG: ${{ needs.decide.outputs.tag }}
-        run: |
-          signature=(); [[ -f dist/SHA256SUMS.sig ]] && signature=(dist/SHA256SUMS.sig)
-          # The release and the latest at once: there is one channel (docs/release-flow.md). Each archive gets a
-          # label (file#label), which GitHub's page shows instead of the file name, so nobody takes the game's
-          # files for the download (#1647). Launchers, servers and install.sh match the name, which stays.
-          gh release create "$TAG" --target "${{ needs.decide.outputs.head }}" --title "$(cat notes/title.txt)" \
-            --notes-file notes/body.md --latest \
-            "dist/horizon-linux-x86_64.tar.gz#Game files the launcher installs: Linux (horizon-linux-x86_64.tar.gz)" \
-            "dist/horizon-windows-x64.zip#Game files the launcher installs: Windows (horizon-windows-x64.zip)" \
-            "dist/horizon-macos-arm64.zip#Game files the launcher installs: macOS (horizon-macos-arm64.zip)" \
-            "dist/horizon-server-linux-x86_64.tar.gz#Dedicated server for Linux (horizon-server-linux-x86_64.tar.gz)" \
-            dist/SHA256SUMS "${signature[@]}" dist/smoke-test.json
-      - name: Dry run, the release that would be published
-        if: needs.decide.outputs.dry_run == 'true'
-        run: |
-          echo "Would publish ${{ needs.decide.outputs.tag }} at ${{ needs.decide.outputs.head }} as the release and latest: $(cat notes/title.txt)"
-          ls -l dist
-      - uses: actions/upload-artifact@v4
-        with:
-          name: release-notes
-          path: notes/
-          retention-days: 3
+          gh workflow run nightly-build.yml --repo "$GITHUB_REPOSITORY" --ref main -f base="$HEAD_SHA" -f urgent="$URGENT"
+          echo "### Started \`nightly build\` on ${HEAD_SHA:0:9}" >> "$GITHUB_STEP_SUMMARY"

.github/workflows/run-parity.yml

@@ -5,11 +5,15 @@ name: run-parity
 # skipped `verify`, and GitHub counts a skipped required check as passed.
 on:
   pull_request:
-    types: [labeled]
+    # A push starts a run only to cancel the old head's (see concurrency): the job runs on the label alone.
+    types: [labeled, synchronize]
 permissions:
   contents: read
 concurrency:
-  group: run-parity-${{ github.event.pull_request.number }}
+  # The run-parity label and pushes share one group per pull request, so the newest run cancels the one before: a
+  # pushed pull request's run tested a head the merge would no longer land. Any other label gets a group of its own:
+  # in the shared one, adding needs-proof cancelled the parity run queued seconds before (run 40766180150).
+  group: run-parity-${{ github.event.pull_request.number }}${{ github.event.action == 'labeled' && github.event.label.name != 'run-parity' && format('-{0}', github.run_id) || '' }}
   cancel-in-progress: true
 env:
   # Test runs never reach the telemetry server: no live-count ping, no uploads (docs/telemetry.md).
@@ -22,3 +26,4 @@ jobs:
     with:
       base: ${{ github.event.pull_request.base.sha }}
       head: ${{ github.event.pull_request.head.sha }}
+      full: ${{ contains(github.event.pull_request.labels.*.name, 'full-parity') }}

.github/workflows/triage-command.yml

@@ -0,0 +1,48 @@
+name: triage command
+# `/close`, `/reopen`, `/label`, `/unlabel` comments: the trusted reviewers in .github/trusted-reviewers.txt (and
+# Ludovic) triage issues and pull requests without any repository role (docs/release-flow.md "Trusted reviewers",
+# tools/ci/triage_command.py).
+#
+# Why no pull request's code runs here, though the token can write:
+# - `issue_comment` always runs this file from main, whoever comments and wherever.
+# - It checks out main's script and list only, never a pull request; it reads threads through the API.
+# - The comment's text and author reach the script as env vars, never in a shell line. The token stays in the step.
+on:
+  issue_comment:
+    types: [created]
+permissions:
+  contents: read
+jobs:
+  command:
+    # Every other comment skips here, before a runner starts.
+    if: >-
+      github.event.comment.user.type != 'Bot' && (
+      startsWith(github.event.comment.body, '/close') ||
+      startsWith(github.event.comment.body, '/reopen') ||
+      startsWith(github.event.comment.body, '/label') ||
+      startsWith(github.event.comment.body, '/unlabel'))
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    permissions:
+      contents: read
+      issues: write
+      pull-requests: write
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          ref: main
+          persist-credentials: false
+          sparse-checkout: |
+            .github/trusted-reviewers.txt
+            tools/ci/nightly_set.py
+            tools/ci/triage_command.py
+          sparse-checkout-cone-mode: false
+      - name: Run the command
+        env:
+          GH_TOKEN: ${{ github.token }}
+          BODY: ${{ github.event.comment.body }}
+          AUTHOR: ${{ github.event.comment.user.login }}
+          ISSUE: ${{ github.event.issue.number }}
+          REPO: ${{ github.repository }}
+          COMMENT_URL: ${{ github.event.comment.html_url }}
+        run: python3 tools/ci/triage_command.py command

AGENTS.md

@@ -10,7 +10,8 @@ Feature → files → harness for the most-changed areas: [docs/architecture.md]
   `tools/check_public_tree.py` rejects them; `git config core.hooksPath .githooks` runs it on commit.
 - **Keep your runs away from real player data.** Any game or launcher you start gets fresh `mktemp -d`
   folders in `HORIZON_HOME` (the game's data), `HORIZON_LAUNCHER_HOME`, `XDG_DATA_HOME` and
-  `XDG_CONFIG_HOME`, plus `HORIZON_LAUNCHER_NO_SELF_UPDATE=1` and `HORIZON_NO_AUDIO=1`. Never write to
+  `XDG_CONFIG_HOME`, plus `HORIZON_LAUNCHER_NO_SELF_UPDATE=1` and `HORIZON_NO_AUDIO=1`, and, for the
+  launcher, `HORIZON_LAUNCHER_TRASH`, `HORIZON_LAUNCHER_CLIPBOARD` and `HORIZON_LAUNCHER_DESKTOP` pointing into the scratch home. Never write to
   `~/.local/share/{applications,horizon,horizon-launcher}` or `~/.local/bin`.
 - **Mark what an agent posts.** A PR body starts with a line naming whose agent opened it and with what.
   Ludovic's agents write `> 🤖 Opened by Ludovic's AI agent (Claude), not by Ludovic himself.`, and a
@@ -34,7 +35,12 @@ Game workspace (root `Cargo.toml`); `launcher/` and `crates/horizon-telemetry-se
 
 | Crate | Owns |
 |---|---|
-| `horizon-client` | The game: a lib (`src/lib.rs`, ~190 flat modules) and the bin (`src/main.rs` → `game.rs` + `game/`), plus `horizon-ctl` (`src/bin/horizon-ctl/`). Also the dedicated server (`--dedicated`) |
+| `horizon-client` | The game: a lib (`src/lib.rs`, ~100 flat modules: gameplay, networking, title screens) and the bin (`src/main.rs` → `game.rs` + `game/`), plus `horizon-ctl` (`src/bin/horizon-ctl/`). Also the dedicated server (`--dedicated`) |
+| `horizon-items` | Blocks and items below gameplay: `blocks.rs` (block facts), `items.rs`, `item_data.rs` (components), `enchant.rs`, `cooldowns.rs`, `bundle.rs`, `item_nbt.rs`. Re-exported as `horizon_client::items`... |
+| `horizon-command` | Command parsing (Brigadier): the vanilla tree, argument types, selectors, suggestions, the tree's network form. Re-exported as `horizon_client::command` |
+| `horizon-client-core` | The client lib's bottom layer: `text.rs`, `lang.rs`, `snbt.rs`, `nbt_path.rs`, `component.rs`, `scoreboard.rs`, `bossbar.rs`, `gamerules.rs`, `block_entity_nbt.rs`, registry/particle/sound tables. Re-exported under the old paths (`horizon_client::text`...) |
+| `horizon-client-input` | Key bindings and key names, toggle keys, mouse options, controller settings and glyphs, the clipboard, window options (`keybinds.rs`, `gamepad.rs`, `mouse.rs`, `window.rs`...). Re-exported under the old paths |
+| `horizon-client-render` | The client's world data, rendering and screens (chunks, meshing, light, streaming, `gfx`, HUD, menus, settings): ~80 modules that horizon-client re-exports under the same paths. Nothing in it reaches gameplay |
 | `horizon-world` | Vanilla world data with no gameplay loop: NBT, regions, chunks, `datafix/`, `worldgen/`, `level/` (server-side block behaviour, ticks, redstone), entity physics, items, effects, food, damage |
 | `horizon-core` | Simulation primitives: Java `Random`s, `jmath` (HotSpot-exact `Math`), positions, noise, density, paletted storage, `version.rs` (the pinned version) |
 | `horizon-protocol` | Network protocol 777: codecs, framing, encryption, `packets/{handshake,status,login,configuration,play}.rs`, `entity_data.rs` |
@@ -54,7 +60,7 @@ Game workspace (root `Cargo.toml`); `launcher/` and `crates/horizon-telemetry-se
 
 Other top-level folders: `tools/` (harnesses and dev scripts), `tests/` (Python unit tests: `python3 -m
 unittest discover -s tests`), `mods/horizon/src/test/java/dev/horizonlab/parity/` (Java oracles),
-`docs/`, `.github/workflows/`. The website (playhorizon.dev) is the private ludovic111/horizon-site: its build
+`docs/`, `.github/workflows/`. The website (playhorizon.dev) is the private horizon-rust/horizon-site: its build
 reads `README.md`, `launcher/links.json`, `docs/api/`, `roadmap/roadmap.json` and `crates/horizon-theme/tokens.css` from main.
 
 ## Build and test fast
@@ -63,6 +69,7 @@ reads `README.md`, `launcher/links.json`, `docs/api/`, `roadmap/roadmap.json` an
 python3 tools/pr_ready.py                  # the self-check: fmt, clippy -D warnings, touched crates' tests, harnesses; paste its block in the PR
 python3 tools/pr_ready.py --quick          # same without harnesses
 cargo test -p horizon-client --lib --bins --tests   # skips the 104 examples (pr_ready does this); `--doc` separately
+cargo test -p horizon-client --features horizon-client/mods --lib mod_content::tests:: -- --ignored   # the 5 slow content-root tests, #[ignore]d; pr_ready runs them when mod content, assets, blocks or items change
 cargo build --profile fast -p horizon-client        # optimized, quick to link: use it to play or run lan_e2e
 python3 tools/parity.py --changed origin/main       # the harnesses your branch can affect (CI's parity job)
 python3 tools/parity.py --changed-files paths.txt --list   # which harnesses cover these files, without running them
@@ -93,6 +100,9 @@ python3 tools/agent_control_e2e.py         # horizon-ctl / MCP end to end
 
 ## Vanilla reference
 
+- Start parity work from the port ledger, not grep: `python3 tools/port_ledger.py issue N` (or `where
+  Class.method`, `what file:line`), and `check --base origin/main` before the PR. How:
+  [.claude/skills/vanilla-parity/SKILL.md](.claude/skills/vanilla-parity/SKILL.md), [docs/port-ledger.md](docs/port-ledger.md).
 - Decompiled sources: `.local/minecraft/26.3/sources/{client,server}/` (`python3 tools/lab.py decompile`).
 - Bytecode queries (callers through lambdas, every overload):
   `python3 tools/rea_vanilla.py method net.minecraft.world.level.block.DispenserBlock dispenseFrom`
@@ -104,30 +114,31 @@ python3 tools/agent_control_e2e.py         # horizon-ctl / MCP end to end
 
 ## horizon-client: where things live
 
-`L:` = lib (`crates/horizon-client/src/`), `G:` = bin (`crates/horizon-client/src/game/`). The lib can't see
+`L:` = lib (`crates/horizon-client/src/`, or `crates/horizon-client-render/src/` for the modules that crate holds, under
+the same `horizon_client::<module>` paths), `G:` = bin (`crates/horizon-client/src/game/`). The lib can't see
 `Game`; bin code reaches the lib as `horizon_client::<module>`.
 
 | Subsystem | Files |
 |---|---|
-| Game loop, tick, frame | `game.rs`: `fn run`, `impl ApplicationHandler for Game` (`window_event`, `about_to_wait`), `fn tick`, `fn tick_world`, `fn render`; L: `clock.rs`, `window.rs`, `spans.rs` |
+| Game loop, tick, frame | `game.rs`: `fn run`, `impl ApplicationHandler for Game` (`window_event`, `about_to_wait`), `fn tick`, `fn tick_world`, `fn render`; L: `clock.rs`, `spans.rs`; `horizon-client-input/src/window.rs` |
 | Rendering | L: `gfx.rs` (`Renderer::new`, `Renderer::render`), `gfx/` (cull, occlusion, translucency, upload, timing, lod, weather, stars, end_sky), `*.wgsl`, `particles.rs`, `block_entity_render.rs`, `item_render.rs`, `fog.rs`, `clouds.rs`, `camera.rs`, `first_person.rs`; G: `render_tick.rs`, `item_draw.rs` |
 | Chunks, streaming, light | L: `streaming.rs` (worker pool: generate, light, mesh), `world.rs`, `chunk.rs`, `chunk_map.rs`, `light.rs`, `mesher.rs` + `mesher/`, `vanillagen.rs` (binds horizon-world's generator), `lod.rs` + `lod/`, `ticket_levels.rs`; G: `world_loading.rs`, `postprocess.rs`; game.rs `fn update_world` |
 | World generation | `crates/horizon-world/src/worldgen/` (`generator*.rs`, `feature_graph.rs`, `structure/`, `carver/`) |
 | Block behaviour | `crates/horizon-world/src/level/` (`mod.rs`, `tick.rs`, `hooks.rs`, `redstone.rs`, `place.rs`, `interact.rs`); game.rs `fn tick_blocks`, `fn process_level_events` |
 | Mobs | L: `mobs.rs` (types), `mobs/` (`ai.rs`, `goals.rs`, `brain.rs`, `*_brain.rs`, `nav.rs`, `path.rs`, `species.rs`, `spawning.rs`, `render.rs`, `anim.rs`); G: `creatures.rs` (ticking, spawning, mob events), one file per mob family (`dragon.rs`, `wither.rs`, `villagers.rs`, `piglins.rs`, `golems.rs`...), `natural_spawning.rs` |
 | Other entities | L: `entities.rs`, `projectiles.rs`, `arrows.rs`; G: `boats.rs`, `minecarts.rs`, `mounts.rs`, `armor_stands.rs`, `paintings.rs`, `frames.rs`, `fireworks.rs`, `tnt.rs`, `explosion.rs` |
-| Player actions | game.rs (`fn use_hand`, `fn use_item`, `fn attack`, `fn tick_mining`, `fn break_block`); G: `hand.rs`, `combat.rs`, `consume.rs`, `potions.rs`, `shield.rs`, `crossbow.rs`, `trident.rs`, `fishing.rs`; L: `motion.rs` + `motion/` (movement), `collisions.rs`, `items.rs`, `item_data.rs` |
+| Player actions | game.rs (`fn use_hand`, `fn use_item`, `fn attack`, `fn tick_mining`, `fn break_block`); G: `hand.rs`, `combat.rs`, `consume.rs`, `potions.rs`, `shield.rs`, `crossbow.rs`, `trident.rs`, `fishing.rs`; L: `motion.rs` + `motion/` (movement), `collisions.rs`; crate `horizon-items`: `items.rs`, `item_data.rs`, `enchant.rs`, `blocks.rs` |
 | Inventory and containers | L: `menu.rs` (`AbstractContainerMenu.clicked`), `container_screen.rs`, `containers.rs`, `creative.rs`, `crafting.rs`, `recipe_book*.rs`, `stations.rs`, `merchant.rs`; game.rs `fn menu_ops`, `fn click_inventory`; G: `stations.rs`, `trading.rs`, `recipe_book.rs`, `machines.rs` |
-| Commands | parse: L: `command/` (`args.rs`, `selector.rs`, `tree_*.rs`, `vanilla.rs`); run: G: `commands.rs` (dispatch) + `commands/*.rs` (`admin`, `execute`, `items`, `players`, `world_cmds`...); L: `scoreboard_cmd.rs`, `data_cmd.rs`, `nbt_path.rs`; G: `functions.rs`, `command_blocks.rs` |
+| Commands | parse: crate `horizon-command` (`args.rs`, `selector.rs`, `tree_*.rs`, `vanilla.rs`); run: G: `commands.rs` (dispatch) + `commands/*.rs` (`admin`, `execute`, `items`, `players`, `world_cmds`...); L: `scoreboard_cmd.rs`, `data_cmd.rs`; `horizon-client-core`: `nbt_path.rs`, `scoreboard.rs`; G: `functions.rs`, `command_blocks.rs` |
 | UI screens | `Screen` enum in game.rs; L: `title.rs` + `title/`, `options_ui.rs`, `multiplayer.rs`, `pack_screen.rs`, `graphics_ui.rs`, `screen_draw.rs`, `ui.rs` (widgets), `hud.rs`, `hud_layout.rs`, `hud_overlays.rs`, `chat.rs`, `tab_list.rs`; G: `startup_menu.rs`, `screens.rs` (pause, death), `options.rs`, `lan_screen.rs`, `chat.rs`, `sign_edit.rs`, `books.rs` |
 | Multiplayer client | L: `net.rs` (network thread); G: `remote.rs` (`fn handle_packet`, `fn tick_remote`), `remote_*.rs` (mob data, objects, projectiles, vehicles, stations) |
 | LAN host / server side | L: `lan/` (`conn.rs` handshake + login threads, `hub.rs` + `hub/` play state, `chunks.rs`, `entity.rs`, `tracking.rs`, `guest.rs`, `playerdata.rs`); G: `lan.rs` (`LanHost`), `lan_actions.rs` (`fn as_guest`, `fn tick_guests`), `lan_*.rs` per feature, `lan_entities.rs` (tracked entities) |
 | Integrated server | G: `integrated.rs` (the server thread), `levels.rs` (one level per dimension, `fn tick_server`), `server_travel.rs` |
 | Dedicated server | G: `dedicated.rs`, `dedicated/status.rs`; crates `horizon-server-files`, `horizon-server` |
-| Save and load | L: `save.rs` (level.dat, regions, playerdata), `entity_nbt.rs`, `block_entity_nbt.rs`, `options_file.rs`; G: `saving.rs`, `persist.rs` (entities); `crates/horizon-world/src/{region.rs,nbt.rs,datafix/}` |
-| Input | game.rs `fn window_event`, `fn key_pressed`, `fn play_mouse`; L: `keybinds.rs`, `keymapping.rs`, `key_names.rs`, `mouse.rs`, `input.rs`, `interaction_input.rs`, `gamepad.rs`, `osk.rs`, `clipboard.rs`; G: `pad.rs`, `pad_menu.rs` |
+| Save and load | L: `save.rs` (level.dat, regions, playerdata), `entity_nbt.rs`, `options_file.rs`; `horizon-client-core/src/block_entity_nbt.rs`; G: `saving.rs`, `persist.rs` (entities); `crates/horizon-world/src/{region.rs,nbt.rs,datafix/}` |
+| Input | game.rs `fn window_event`, `fn key_pressed`, `fn play_mouse`; crate `horizon-client-input` (`keybinds.rs`, `keymapping.rs`, `key_names.rs`, `mouse.rs`, `input.rs`, `interaction_input.rs`, `gamepad.rs`, `clipboard.rs`); L: `osk.rs`; G: `pad.rs`, `pad_menu.rs` |
 | Audio | L: `audio.rs` (mixer), `sound_engine.rs`, `sound_events.rs`, `music.rs`, `ambience.rs`; G: `music.rs`, `subtitle_hud.rs` |
-| Resource packs | L: `packs.rs` + `packs/`, `pack_screen.rs`, `atlas_sources.rs`, `sprites.rs`, `mipmap.rs`, `model_library.rs`, `font.rs`, `lang.rs`; crate `horizon-assets`; G: `packs.rs` |
+| Resource packs | L: `packs.rs` + `packs/`, `pack_screen.rs`, `atlas_sources.rs`, `sprites.rs`, `mipmap.rs`, `model_library.rs`, `font.rs`; `horizon-client-core/src/lang.rs`; crate `horizon-assets`; G: `packs.rs` |
 | Agent control | L: `control.rs` (socket), `bin/horizon-ctl/`; G: `control.rs`, `agent.rs`, `events.rs`, `ui_control.rs` ([docs/agent-control.md](docs/agent-control.md)) |
 | Mods | crate `horizon-mods`; G: `mods.rs`; L: `mod_content.rs`, `mod_list.rs` |
 | Horizon extras, settings | L: `extras.rs`, `graphics.rs`, `settings.rs`, `minimap.rs`; G: `extras.rs`, `tweaks.rs`, `options.rs` |

CONTRIBUTING.md

@@ -86,6 +86,9 @@ configuration and toolchain changes select the whole workspace; CI also keeps it
   release notes), `skip-release` when players see no change (tooling, docs, tests), nothing for a fix.
   `release-now` is for crash fixes that shouldn't wait. pr_ready suggests one.
 
+Who reviews and merges: the Horizon Team, on CI for ordinary pull requests; risky ones (saves, network, world
+generation, the launcher's updates) wait for a local proof first ([merging](docs/release-flow.md#merging)).
+
 Every merge to main is released automatically ([release flow](docs/release-flow.md)), so main always stays playable.
 How agents, checks, releases and signed updates keep this safe: [security](docs/security.md).
 
@@ -98,5 +101,5 @@ new pushes, we add it again.
 
 ## Talk to us
 
-[Discord](https://discord.gg/HcTeMZxe5E) for questions and ideas, [issues](https://github.com/ludovic111/horizon/issues)
+[Discord](https://discord.gg/HcTeMZxe5E) for questions and ideas, [issues](https://github.com/horizon-rust/horizon/issues)
 for bugs. If you want to take something on, say so in its issue so nobody else starts the same work.

Cargo.lock

@@ -876,6 +876,12 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d8b14ccef22fc6f5a8f4d7d768562a182c04ce9a3b3157b91390b52ddfdf1a76"
 
+[[package]]
+name = "dunce"
+version = "1.0.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "92773504d58c093f6de2459af4af33faa518c13451eb8f2b5698ed3d36e7c813"
+
 [[package]]
 name = "either"
 version = "1.19.0"
@@ -930,6 +936,13 @@ version = "3.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b5343afd4a8365a643ac588dab4cf234a190c7f6c88c9f6dd6ffe00837661b7"
 
+[[package]]
+name = "far-view"
+version = "1.0.0"
+dependencies = [
+ "horizon-mod-sdk",
+]
+
 [[package]]
 name = "fdeflate"
 version = "0.3.7"
@@ -1363,19 +1376,22 @@ name = "horizon-client"
 version = "0.1.0"
 dependencies = [
  "ab_glyph",
- "arboard",
  "bytemuck",
  "chrono",
- "cpal",
  "flate2",
  "gilrs",
  "glam",
  "horizon-assets",
  "horizon-bench",
+ "horizon-client-core",
+ "horizon-client-input",
+ "horizon-client-render",
+ "horizon-command",
  "horizon-core",
  "horizon-dualsense",
  "horizon-friends",
  "horizon-hdr",
+ "horizon-items",
  "horizon-mods",
  "horizon-protocol",
  "horizon-server-files",
@@ -1388,21 +1404,93 @@ dependencies = [
  "log",
  "miniz_oxide 0.8.9",
  "naga",
+ "open",
+ "png",
+ "pollster",
+ "rustix 1.1.5",
+ "serde",
+ "serde_json",
+ "sha1",
+ "sha2",
+ "unicode-bidi",
+ "ureq",
+ "wgpu",
+ "winit",
+ "winresource",
+ "zip",
+]
+
+[[package]]
+name = "horizon-client-core"
+version = "0.1.0"
+dependencies = [
+ "horizon-world",
+ "serde_json",
+]
+
+[[package]]
+name = "horizon-client-input"
+version = "0.1.0"
+dependencies = [
+ "arboard",
+ "horizon-client-core",
+ "horizon-dualsense",
+ "horizon-theme",
+ "png",
+ "winit",
+]
+
+[[package]]
+name = "horizon-client-render"
+version = "0.1.0"
+dependencies = [
+ "ab_glyph",
+ "bytemuck",
+ "chrono",
+ "cpal",
+ "flate2",
+ "glam",
+ "horizon-assets",
+ "horizon-bench",
+ "horizon-client-core",
+ "horizon-client-input",
+ "horizon-command",
+ "horizon-core",
+ "horizon-hdr",
+ "horizon-items",
+ "horizon-protocol",
+ "horizon-shader-api",
+ "horizon-shaders",
+ "horizon-telemetry",
+ "horizon-theme",
+ "horizon-threads",
+ "horizon-world",
+ "log",
+ "miniz_oxide 0.8.9",
+ "naga",
  "png",
  "pollster",
  "rustix 1.1.5",
  "serde",
  "serde_json",
- "sha1",
  "sha2",
  "symphonia",
+ "unicode-bidi",
  "ureq",
  "wgpu",
  "winit",
- "winresource",
  "zip",
 ]
 
+[[package]]
+name = "horizon-command"
+version = "0.1.0"
+dependencies = [
+ "horizon-client-core",
+ "horizon-protocol",
+ "horizon-world",
+]
+
 [[package]]
 name = "horizon-core"
 version = "0.1.0"
@@ -1442,6 +1530,17 @@ dependencies = [
  "wgpu",
 ]
 
+[[package]]
+name = "horizon-items"
+version = "0.1.0"
+dependencies = [
+ "horizon-client-core",
+ "horizon-core",
+ "horizon-world",
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "horizon-mod-sdk"
 version = "0.1.0"
@@ -1826,6 +1925,25 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "is-docker"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "928bae27f42bc99b60d9ac7334e3a21d10ad8f1835a4e12ec3ec0464765ed1b3"
+dependencies = [
+ "once_cell",
+]
+
+[[package]]
+name = "is-wsl"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "173609498df190136aa7dea1a91db051746d339e18476eed5ca40521f02d7aa5"
+dependencies = [
+ "is-docker",
+ "once_cell",
+]
+
 [[package]]
 name = "itertools"
 version = "0.14.0"
@@ -2640,6 +2758,17 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08d65885ee38876c4f86fa503fb49d7b507c2b62552df7c70b2fce627e06381"
 
+[[package]]
+name = "open"
+version = "5.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8d8c8b8e725ad26404d6896eb2f064294a0a7b4f1d9120210d85544684c4ca95"
+dependencies = [
+ "dunce",
+ "is-wsl",
+ "libc",
+]
+
 [[package]]
 name = "orbclient"
 version = "0.3.55"
@@ -2978,6 +3107,13 @@ dependencies = [
  "objc2-quartz-core 0.3.2",
 ]
 
+[[package]]
+name = "recipes"
+version = "1.0.0"
+dependencies = [
+ "horizon-mod-sdk",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.4.1"
@@ -3148,9 +3284,9 @@ dependencies = [
 
 [[package]]
 name = "rustls-webpki"
-version = "0.103.15"
+version = "0.103.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3c3cf1d8b1e7d4927e2d154c3fcb02979afb9939629c62cd9048d4f07b60ac2"
+checksum = "4443b1b6d39d7c663139942cc4558262562d2c84123bb6282ef177009ca8b281"
 dependencies = [
  "ring",
  "rustls-pki-types",
@@ -3741,6 +3877,12 @@ version = "1.20.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6f5e870be6c3b371b77fe0ee0bafb859fa4964b4404c27de1d380043c4dda20"
 
+[[package]]
+name = "unicode-bidi"
+version = "0.3.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5c1cb5db39152898a79168971543b1cb5020dff7fe43c8dc468b0885f5e29df5"
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.26"
@@ -4322,14 +4464,14 @@ version = "0.26.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "521bc38abb08001b01866da9f51eb7c5d647a19260e00054a8c7fd5f9e57f7a9"
 dependencies = [
- "webpki-roots 1.0.9",
+ "webpki-roots 1.0.10",
 ]
 
 [[package]]
 name = "webpki-roots"
-version = "1.0.9"
+version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7dcd9d09a39985f5344844e66b0c530a33843579125f23e21e9f0f220850f22a"
+checksum = "1c1c8e20c8a38fc7d65abfe74eb7280e4aa667e8eec8bc84996d2874810748d9"
 dependencies = [
  "rustls-pki-types",
 ]

Cargo.toml

@@ -1,6 +1,49 @@
 [workspace]
 exclude = ["launcher", "crates/horizon-telemetry-server", "crates/horizon-mod-registry", "third_party/wgpu-hal"]
-members = ["crates/horizon-core", "crates/horizon-dualsense", "crates/horizon-threads", "crates/horizon-hdr", "crates/horizon-world", "crates/horizon-client", "crates/horizon-server-files", "crates/horizon-server", "crates/horizon-bots", "crates/horizon-assets", "crates/horizon-protocol", "crates/horizon-theme", "crates/horizon-prepare", "crates/horizon-telemetry", "crates/horizon-bench", "crates/horizon-friends", "crates/horizon-relay", "crates/horizon-mod-sdk", "crates/horizon-mods", "crates/horizon-mods/tests/guest", "crates/horizon-mods/tests/ui_guest", "crates/cargo-horizon-mod", "crates/horizon-port-pack", "crates/horizon-shaders", "crates/horizon-shader-api", "crates/horizon-release-sign", "crates/horizon-mod-sdk/examples/coords-hud", "crates/horizon-mod-sdk/examples/predator-missile", "crates/horizon-mod-sdk/examples/welcome", "crates/horizon-mod-sdk/examples/beacons", "mods/official/fps-overlay", "mods/official/keystrokes", "mods/official/minimap", "mods/official/zoom", "xtask"]
+members = [
+    "crates/horizon-core",
+    "crates/horizon-dualsense",
+    "crates/horizon-threads",
+    "crates/horizon-hdr",
+    "crates/horizon-world",
+    "crates/horizon-client",
+    "crates/horizon-client-core",
+    "crates/horizon-client-input",
+    "crates/horizon-client-render",
+    "crates/horizon-command",
+    "crates/horizon-items",
+    "crates/horizon-server-files",
+    "crates/horizon-server",
+    "crates/horizon-bots",
+    "crates/horizon-assets",
+    "crates/horizon-protocol",
+    "crates/horizon-theme",
+    "crates/horizon-prepare",
+    "crates/horizon-telemetry",
+    "crates/horizon-bench",
+    "crates/horizon-friends",
+    "crates/horizon-relay",
+    "crates/horizon-mod-sdk",
+    "crates/horizon-mods",
+    "crates/horizon-mods/tests/guest",
+    "crates/horizon-mods/tests/ui_guest",
+    "crates/cargo-horizon-mod",
+    "crates/horizon-port-pack",
+    "crates/horizon-shaders",
+    "crates/horizon-shader-api",
+    "crates/horizon-release-sign",
+    "crates/horizon-mod-sdk/examples/coords-hud",
+    "crates/horizon-mod-sdk/examples/predator-missile",
+    "crates/horizon-mod-sdk/examples/welcome",
+    "crates/horizon-mod-sdk/examples/beacons",
+    "mods/official/fps-overlay",
+    "mods/official/keystrokes",
+    "mods/official/far-view",
+    "mods/official/minimap",
+    "mods/official/zoom",
+    "xtask",
+    "mods/official/recipes",
+]
 resolver = "2"
 
 [workspace.package]
@@ -19,8 +62,10 @@ large_enum_variant = "allow"
 # wgpu-hal 30.0.1 with gfx-rs/wgpu#10124: wgpu 30 creates a Vulkan descriptor
 # pool with no pool sizes while it creates the device, which Vulkan allows only
 # since 1.3.215, and Intel's Windows driver for 6th-10th gen iGPUs (HD 520/530,
-# UHD 620/630) crashes on it with an access violation (#746). Drop this and the
-# folder once a wgpu release has the fix.
+# UHD 620/630) crashes on it with an access violation (#746). It also fixes the
+# Metal backend's lookup of the CoreGraphics HDR colour space names, which handed
+# CoreGraphics a symbol's address as the string and crashed HDR output on macOS.
+# Drop this and the folder once a wgpu release has both fixes.
 [patch.crates-io]
 wgpu-hal = { path = "third_party/wgpu-hal" }
 

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2026 Ludovic
+Copyright (c) 2026 Ludovic Marie and the Horizon contributors
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -1,9 +1,9 @@
 <p align="center">
-  <img src="docs/media/banner.webp" alt="Horizon: Minecraft: Java Edition 26.3, rewritten in Rust and checked against vanilla by 281 differential harnesses" width="100%">
+  <img src="docs/media/banner.webp" alt="Horizon: Minecraft: Java Edition 26.3, rewritten in Rust and checked against vanilla by more than 300 differential harnesses" width="100%">
 </p>
 
 <p align="center">
-  <a href="https://github.com/ludovic111/horizon/actions/workflows/ci.yml"><img src="https://github.com/ludovic111/horizon/actions/workflows/ci.yml/badge.svg?branch=main" alt="CI"></a>
+  <a href="https://github.com/horizon-rust/horizon/actions/workflows/ci.yml"><img src="https://github.com/horizon-rust/horizon/actions/workflows/ci.yml/badge.svg?branch=main" alt="CI"></a>
   <img src="https://img.shields.io/badge/Minecraft-Java%2026.3-5D9C3F" alt="Minecraft Java 26.3">
   <img src="https://img.shields.io/badge/Rust-stable-B7410E?logo=rust&logoColor=white" alt="Rust">
   <img src="https://img.shields.io/badge/vanilla%20parity-100%25-F0795A" alt="Vanilla parity 100%">
@@ -15,7 +15,7 @@
   <a href="https://playhorizon.dev"><b>Website</b></a> ·
   <a href="#download"><b>Download</b></a> ·
   <a href="https://playhorizon.dev/docs/"><b>Documentation</b></a> ·
-  <a href="https://github.com/ludovic111/horizon/releases"><b>Release notes</b></a> ·
+  <a href="https://github.com/horizon-rust/horizon/releases"><b>Release notes</b></a> ·
   <a href="ROADMAP.md"><b>Roadmap</b></a> ·
   <a href="#project-status"><b>Project status</b></a> ·
   <a href="#contributing"><b>Contributing</b></a>
@@ -23,15 +23,15 @@
 
 # Horizon
 
-Horizon is Minecraft: Java Edition 26.3 rewritten in Rust: a native game that reads the same worlds, follows the same rules and generates the same terrain as the Java game, and is checked against it by 281 differential harnesses. You play it through a small launcher, on the files from your own copy of Minecraft. It is free, open source and unofficial.
+Horizon is Minecraft: Java Edition 26.3 rewritten in Rust: a native game that reads the same worlds, follows the same rules and generates the same terrain as the Java game, and is checked against it by more than 300 differential harnesses. You play it through a small launcher, on the files from your own copy of Minecraft. It is free, open source and unofficial.
 
 > Not an official Minecraft product. Not approved by or associated with Mojang or Microsoft. Horizon contains no Minecraft code, assets or data: you need your own legally obtained copy of Minecraft: Java Edition 26.3.
 
 ## Download
 
-Horizon is installed through **the Horizon launcher**. Get it from [playhorizon.dev](https://playhorizon.dev) (the Download button picks your system) or from [the launcher releases](https://github.com/ludovic111/horizon/releases?q=launcher-v&expanded=true), for Linux x86-64, macOS on Apple Silicon or Windows x64. The launcher installs and updates the game, prepares its files from your own copy of Minecraft, and updates itself.
+Horizon is installed through **the Horizon launcher**. Get it from [playhorizon.dev](https://playhorizon.dev) (the Download button picks your system) or from [the launcher releases](https://github.com/horizon-rust/horizon/releases?q=launcher-v&expanded=true), for Linux x86-64, macOS on Apple Silicon or Windows x64. The launcher installs the game and keeps it up to date with each new build (Horizon ships on one channel, the Nightly), prepares its files from your copy of Minecraft (your own install, or downloaded from Mojang for your account), and updates itself.
 
-**You need** Minecraft: Java Edition 26.3, played once (the official launcher, Prism, MultiMC and other launchers all work); a Java 25 runtime, for the one-time preparation; and a GPU with Vulkan on Linux and Windows, or any Apple Silicon Mac. Step by step, with macOS's first-open prompt and the first launch: [Install and first launch](https://playhorizon.dev/docs/install).
+**You need** a Microsoft account that owns Minecraft: Java Edition (the launcher signs in with it, as other launchers do; see [Microsoft account](docs/microsoft-account.md)) and a GPU with Vulkan or OpenGL 3.3 on Linux, Vulkan or DirectX 12 on Windows, or any Apple Silicon Mac. Nothing else: with no Minecraft on your computer, Play downloads 26.3 and the Java it needs from Mojang for your account, as the official launcher does, then prepares it once. An install you already have (the official launcher, Prism, MultiMC and other launchers all work) is used instead. Step by step, with macOS's first-open prompt and the first launch: [Install and first launch](https://playhorizon.dev/docs/install).
 
 <table>
   <tr>
@@ -47,8 +47,8 @@ The [documentation](https://playhorizon.dev/docs/) covers each of these.
 - **The game:** singleplayer with vanilla's world generation, mobs, villagers, raids, redstone, every command, the HUD and the recipe book, on saves in vanilla's format. Worlds from 1.8 to 26.2 are upgraded as vanilla does. [Status table](#project-status).
 - **Horizon's own extras:** new menus (vanilla's are one setting away), graphics presets, distant terrain up to 1024 chunks, controller support, optional zoom, minimap and more, all off by default where they would change the vanilla look. See [Settings](https://playhorizon.dev/docs/settings).
 - **Resource packs and data packs:** resource packs work, and data packs load functions, predicates and item modifiers.
-- **Playing with others:** invite friends from the pause menu's Friends button with a code, Open to LAN, and joining offline-mode servers. Horizon cannot sign in to a Microsoft account yet, so it cannot join servers that check accounts. See [Multiplayer](https://playhorizon.dev/docs/multiplayer).
-- **Mods:** Horizon has its own mod system (Rust compiled to WebAssembly). Java mod jars do not run. See [Mods and data packs](https://playhorizon.dev/docs/mods).
+- **Playing with others:** invite friends from the pause menu's Friends button with a code, Open to LAN, and joining servers, online-mode ones with the Microsoft account the launcher signs in with. See [Multiplayer](https://playhorizon.dev/docs/multiplayer).
+- **Mods:** Horizon has its own mods, installed from the launcher. The official ones (Zoom, FPS Counter, Keystrokes and Minimap) are native Rust that the launcher builds into your game, with no Rust to install; older WebAssembly mods still run while they move. Java mod jars do not run in Horizon. See [Mods and data packs](https://playhorizon.dev/docs/mods).
 
 Screenshots, captured in the Rust client itself with vanilla assets and no mods or shaders:
 
@@ -93,13 +93,13 @@ Commands block until the action is done and reply with what happened; errors are
 
 For developers. Requirements: Rust 1.90 or newer, Python 3.10 or newer, JDK 25, and on Linux the ALSA and udev development headers (`libasound2-dev libudev-dev` on Debian and Ubuntu). Development and the vanilla harnesses run on Linux.
 
-Horizon contains no game files and never downloads them. It builds its resources from **your own copy** of Minecraft: Java Edition 26.3, verified against the checksums in `research-lock.json`:
+Horizon contains no game files, and `horizon-prepare` never downloads them (the launcher downloads them from Mojang only for a signed-in account that owns the game). It builds its resources from **your own copy** of Minecraft: Java Edition 26.3, verified against the checksums in `research-lock.json`:
 
 1. **Client:** install Java Edition with the official launcher and play 26.3 once. Horizon reads `versions/26.3/`, `libraries/` and `assets/` from the launcher's game directory (`~/.minecraft` on Linux). If yours lives elsewhere, pass `--minecraft-dir` or set `HORIZON_MINECRAFT_DIR`.
 2. **Server jar:** the 26.3 server jar, from the `downloads.server.url` in your launcher's `versions/26.3/26.3.json` (or [minecraft.net/download/server](https://www.minecraft.net/en-us/download/server) while 26.3 is the current release). Pass it with `--server-jar` or set `HORIZON_SERVER_JAR`. It is only needed the first time.
 
 ```sh
-git clone https://github.com/ludovic111/horizon.git
+git clone https://github.com/horizon-rust/horizon.git
 cd horizon
 cargo run --release -p horizon-prepare -- --prepare --server-jar ~/Downloads/server.jar   # needs JDK 25
 cargo run --release -p horizon-prepare -- sounds   # optional: sounds from your launcher install
@@ -139,6 +139,11 @@ average; `tests/test_parity.py` keeps it in sync with this table. Last audited
 rerun whenever one of its inputs changed, and the Mac mini now runs every one of
 them too (Rust uses Java's own float maths on each platform).
 
+The harnesses measure behaviour. A second measure is method by method: the [port ledger](tools/port_ledger.py)
+lists every method of vanilla 26.3 next to the Rust functions that port it, with a verdict for each one
+(ported, folded into another function, missing, or needing no port), and the untested ports. Run
+`python3 tools/port_ledger.py build`, then `coverage`, with the vanilla data in `.local/`.
+
 | Subsystem | Score | Main gaps |
 | --- | ---: | --- |
 | Window, input and game loop | 1 | None: the game loop, options, camera, auto-jump, toggle sprint/sneak, local input and the frame limiter match vanilla |
@@ -158,7 +163,7 @@ them too (Rust uses Java's own float maths on each platform).
 
 ### Known issues
 
-Horizon can't sign in to a Microsoft account yet, so it can't join online-mode servers (it joins offline-mode ones); skins served over https show the default skin unless already cached; pack icons show the unknown-pack texture in game; the creative hotbar keys (C/X) aren't wired to the hotbar loader; item tooltips lack attribute lines.
+Skins served over https show the default skin unless already cached; pack icons show the unknown-pack texture in game; the creative hotbar keys (C/X) aren't wired to the hotbar loader; item tooltips lack attribute lines.
 
 ## Licence
 

ROADMAP.md

@@ -16,7 +16,7 @@ Horizon is Minecraft: Java Edition 26.3 rewritten from scratch in Rust, so it ru
 - **Single player as a server: the last differences**: Single player now runs a small server in the background, as vanilla does. We are fixing what still behaves differently there; every fix also works for LAN and server players.
 - **Horizon's mod registry**: One place for mods, modpacks and resource packs made for Horizon: browse them on the website and install them from the launcher in one click.
 
-**Next**: Microsoft sign-in (coming soon); CurseForge in the mod browser (coming soon); Fresh benchmarks against vanilla; Pistons push players and mobs; Horizon on Intel Macs; Faster world creation and entry on small CPUs; Servers that hold 20 TPS with 50 to 100 players; Low-end computers: Steam Deck, old Macs, 8 GB; Native upscaling; A batch of targeted optimisations; A Convert to Rust button for what isn't rewritten yet; Mods with code: machines, magic, mobs; Data packs in the mod browser; Prepare a version without Java; Server console, bans and a full admin API; Hosting polish: Windows service, safe updates; Guided hosting with Tailscale and an invite button; An official Docker image for servers; One single-player path: remove the in-frame world; Villages and combat, exactly as in vanilla; Choose the audio output device; Mods that read and change the world; Machines and blocks with inventories (API 0.4); Lua and other languages for mods; Well-known shader looks, rewritten for Horizon; A visible beta label; Wayland and Hyprland polish; A versioned agent-control protocol; Port mods with your own AI agent; Horizon on X (coming soon); Pipeline protection and a GitHub App for agents; Signed updates everywhere, installers included; A server you install with one command.
+**Next**: A new launcher design; CurseForge in the mod browser (coming soon); Fresh benchmarks against vanilla; Pistons push players and mobs; Horizon on Intel Macs; Faster world creation and entry on small CPUs; Servers that hold 20 TPS with 50 to 100 players; Low-end computers: Steam Deck, old Macs, 8 GB; Native upscaling; A batch of targeted optimisations; A Convert to Rust button for what isn't rewritten yet; Mods with code: machines, magic, mobs; Data packs in the mod browser; Prepare a version without Java; Server console, bans and a full admin API; Hosting polish: Windows service, safe updates; Guided hosting with Tailscale and an invite button; An official Docker image for servers; One single-player path: remove the in-frame world; Villages and combat, exactly as in vanilla; Choose the audio output device; Mods that read and change the world; Machines and blocks with inventories (API 0.4); Well-known shader looks, rewritten for Horizon; A visible beta label; Wayland and Hyprland polish; A versioned agent-control protocol; Port mods with your own AI agent; Horizon on X (coming soon); Pipeline protection and a GitHub App for agents; Signed updates everywhere, installers included; A server you install with one command; Ready-made setups for hosting panels.
 
 **How to help**: Play it and tell us what differs from vanilla (Discord or GitHub), run the benchmark on your computer, vote for what you want next, or pick one of the Help wanted items.
 
@@ -32,7 +32,7 @@ Making Horizon faster than vanilla on every computer, with smooth camera movemen
 
 <details><summary>Technical</summary>
 
-Frame pacing at render distance 32 ([#678](https://github.com/ludovic111/horizon/issues/678)): long frames come from work competing with the render thread. In review: world generation workers build free structure starts instead of queueing them ([#1760](https://github.com/ludovic111/horizon/issues/1760)), the worker pool leaves one core as vanilla does ([#1778](https://github.com/ludovic111/horizon/issues/1778)), and the terrain vertex arena is read as storage where flat draws run ([#1742](https://github.com/ludovic111/horizon/issues/1742)). Still open: far terrain at 48 to 64 chunks ([#718](https://github.com/ludovic111/horizon/issues/718)) and CPU-bound fields of block entities ([#717](https://github.com/ludovic111/horizon/issues/717)). Every change shows before and after numbers from `tools/perf_bench.py` against vanilla 26.3 ([docs/benchmark.md](docs/benchmark.md)).
+Frame pacing at render distance 32 ([#678](https://github.com/horizon-rust/horizon/issues/678)): long frames come from work competing with the render thread. In review: world generation workers build free structure starts instead of queueing them ([#1760](https://github.com/horizon-rust/horizon/issues/1760)), the worker pool leaves one core as vanilla does ([#1778](https://github.com/horizon-rust/horizon/issues/1778)), and the terrain vertex arena is read as storage where flat draws run ([#1742](https://github.com/horizon-rust/horizon/issues/1742)). Still open: far terrain at 48 to 64 chunks ([#718](https://github.com/horizon-rust/horizon/issues/718)) and CPU-bound fields of block entities ([#717](https://github.com/horizon-rust/horizon/issues/717)). Every change shows before and after numbers from `tools/perf_bench.py` against vanilla 26.3 ([docs/benchmark.md](docs/benchmark.md)).
 
 </details>
 
@@ -42,7 +42,7 @@ Speeding up the code that reads and writes the blocks of the world, which almost
 
 <details><summary>Technical</summary>
 
-`PalettedContainer` and `PackedStorage` find an entry's word by multiply and shift instead of an integer division ([#1790](https://github.com/ludovic111/horizon/issues/1790), [#1794](https://github.com/ludovic111/horizon/issues/1794)); meshing looks up baked models by index, not by name ([#1747](https://github.com/ludovic111/horizon/issues/1747)). Each change keeps the paletted storage harnesses identical and shows its microbenchmark ([docs/performance/paletted-container-access-results.md](docs/performance/paletted-container-access-results.md)).
+`PalettedContainer` and `PackedStorage` find an entry's word by multiply and shift instead of an integer division ([#1790](https://github.com/horizon-rust/horizon/issues/1790), [#1794](https://github.com/horizon-rust/horizon/issues/1794)); meshing looks up baked models by index, not by name ([#1747](https://github.com/horizon-rust/horizon/issues/1747)). Each change keeps the paletted storage harnesses identical and shows its microbenchmark ([docs/performance/paletted-container-access-results.md](docs/performance/paletted-container-access-results.md)).
 
 </details>
 
@@ -54,7 +54,7 @@ Making the world-generation mods of popular modpacks (new structures, YUNG's dun
 
 <details><summary>Technical</summary>
 
-`horizon-port-pack` carries a pack's data-driven content over; structure mods that need code get a native port: YUNG's worldgen as written ([#1746](https://github.com/ludovic111/horizon/issues/1746)), Lithostitched's limited and guaranteed elements with pool and processor modifiers ([#1777](https://github.com/ludovic111/horizon/issues/1777)), its processors as the game's own types ([#1765](https://github.com/ludovic111/horizon/issues/1765)). Proved by the structure blocks and layout harnesses ([#1753](https://github.com/ludovic111/horizon/issues/1753), [#1757](https://github.com/ludovic111/horizon/issues/1757)). Mods whose Java code does more than world generation don't run ([docs/modpacks.md](docs/modpacks.md)).
+`horizon-port-pack` carries a pack's data-driven content over; structure mods that need code get a native port: YUNG's worldgen as written ([#1746](https://github.com/horizon-rust/horizon/issues/1746)), Lithostitched's limited and guaranteed elements with pool and processor modifiers ([#1777](https://github.com/horizon-rust/horizon/issues/1777)), its processors as the game's own types ([#1765](https://github.com/horizon-rust/horizon/issues/1765)). Proved by the structure blocks and layout harnesses ([#1753](https://github.com/horizon-rust/horizon/issues/1753), [#1757](https://github.com/horizon-rust/horizon/issues/1757)). Mods whose Java code does more than world generation don't run ([docs/modpacks.md](docs/modpacks.md)).
 
 </details>
 
@@ -66,7 +66,7 @@ When you play on a server, other players, mobs, items and menus look and behave
 
 <details><summary>Technical</summary>
 
-Client-of-a-server fixes in `game/remote*.rs` and `horizon-protocol`: mobs' aggressive and item-use flags ([#1802](https://github.com/ludovic111/horizon/issues/1802), [#1798](https://github.com/ludovic111/horizon/issues/1798)), ghost items after a remote menu ([#1795](https://github.com/ludovic111/horizon/issues/1795)), skins ([#1652](https://github.com/ludovic111/horizon/issues/1652)), cookies and transfer packets for proxy networks ([#1650](https://github.com/ludovic111/horizon/issues/1650)), firework boosts ([#1671](https://github.com/ludovic111/horizon/issues/1671)), living-entity attributes and simulation distance ([#1731](https://github.com/ludovic111/horizon/issues/1731)), styled item names ([#1702](https://github.com/ludovic111/horizon/issues/1702)), primed TNT between updates ([#1710](https://github.com/ludovic111/horizon/issues/1710)).
+Client-of-a-server fixes in `game/remote*.rs` and `horizon-protocol`: mobs' aggressive and item-use flags ([#1802](https://github.com/horizon-rust/horizon/issues/1802), [#1798](https://github.com/horizon-rust/horizon/issues/1798)), ghost items after a remote menu ([#1795](https://github.com/horizon-rust/horizon/issues/1795)), skins ([#1652](https://github.com/horizon-rust/horizon/issues/1652)), cookies and transfer packets for proxy networks ([#1650](https://github.com/horizon-rust/horizon/issues/1650)), firework boosts ([#1671](https://github.com/horizon-rust/horizon/issues/1671)), living-entity attributes and simulation distance ([#1731](https://github.com/horizon-rust/horizon/issues/1731)), styled item names ([#1702](https://github.com/horizon-rust/horizon/issues/1702)), primed TNT between updates ([#1710](https://github.com/horizon-rust/horizon/issues/1710)).
 
 </details>
 
@@ -76,7 +76,7 @@ Servers that show dialogs, such as the register and login screens of AuthMe, wil
 
 <details><summary>Technical</summary>
 
-26.3's dialog packets and model ([#1720](https://github.com/ludovic111/horizon/issues/1720)), the dialog screen with its buttons and actions ([#1734](https://github.com/ludovic111/horizon/issues/1734)), then text and boolean inputs ([#1735](https://github.com/ludovic111/horizon/issues/1735)).
+26.3's dialog packets and model ([#1720](https://github.com/horizon-rust/horizon/issues/1720)), the dialog screen with its buttons and actions ([#1734](https://github.com/horizon-rust/horizon/issues/1734)), then text and boolean inputs ([#1735](https://github.com/horizon-rust/horizon/issues/1735)).
 
 </details>
 
@@ -86,7 +86,7 @@ A /pregen command that builds an area of the world ahead of time, so players don
 
 <details><summary>Technical</summary>
 
-Generates, lights and saves an area before anyone walks there ([#1805](https://github.com/ludovic111/horizon/issues/1805), a contributor's pull request, in review). Useful on servers, and it moves the generation cost away from the first visit; the generation speed-ups are under 'Steady frames at long render distances'.
+Generates, lights and saves an area before anyone walks there ([#1805](https://github.com/horizon-rust/horizon/issues/1805), a contributor's pull request, in review). Useful on servers, and it moves the generation cost away from the first visit; the generation speed-ups are under 'Steady frames at long render distances'.
 
 </details>
 
@@ -98,43 +98,55 @@ One place for mods, modpacks and resource packs made for Horizon: browse them on
 
 <details><summary>Technical</summary>
 
-Merged: the registry index (schema 1, `.hpack`, checks before install, [#1634](https://github.com/ludovic111/horizon/issues/1634)), `cargo horizon-mod check` ([#1642](https://github.com/ludovic111/horizon/issues/1642)) and the submission service (`crates/horizon-mod-registry`, [#1659](https://github.com/ludovic111/horizon/issues/1659)). In review: the website's /mods ([#1596](https://github.com/ludovic111/horizon/issues/1596)) and /mods/submit ([#1635](https://github.com/ludovic111/horizon/issues/1635)), and in the launcher the registry as a source ([#1636](https://github.com/ludovic111/horizon/issues/1636)), install, enable and takedowns ([#1637](https://github.com/ludovic111/horizon/issues/1637)), the Mods page ([#1638](https://github.com/ludovic111/horizon/issues/1638)) and modpacks as their own profiles ([#1640](https://github.com/ludovic111/horizon/issues/1640)).
+Merged: the registry index (schema 1, `.hpack`, checks before install, [#1634](https://github.com/horizon-rust/horizon/issues/1634)), `cargo horizon-mod check` ([#1642](https://github.com/horizon-rust/horizon/issues/1642)) and the submission service (`crates/horizon-mod-registry`, [#1659](https://github.com/horizon-rust/horizon/issues/1659)). In review: the website's /mods ([#1596](https://github.com/horizon-rust/horizon/issues/1596)) and /mods/submit ([#1635](https://github.com/horizon-rust/horizon/issues/1635)), and in the launcher the registry as a source ([#1636](https://github.com/horizon-rust/horizon/issues/1636)), install, enable and takedowns ([#1637](https://github.com/horizon-rust/horizon/issues/1637)), the Mods page ([#1638](https://github.com/horizon-rust/horizon/issues/1638)) and modpacks as their own profiles ([#1640](https://github.com/horizon-rust/horizon/issues/1640)).
 
 More: [docs/mods.md](docs/mods.md)
 
 </details>
 
+#### Native mods, built by the launcher
+
+Horizon's own mods become native code that the launcher builds into your game, with no Rust to install: Zoom, FPS Counter, Keystrokes and Minimap already are, and Recipes is next.
+
+<details><summary>Technical</summary>
+
+Stable hook points in the game (game/native_hooks.rs, [#3345](https://github.com/horizon-rust/horizon/issues/3345), [#3346](https://github.com/horizon-rust/horizon/issues/3346); v2 with the item panel and recipe pages, [#3434](https://github.com/horizon-rust/horizon/issues/3434), [#3435](https://github.com/horizon-rust/horizon/issues/3435)), horizon-mixins applied by the launcher with its own portable Rust ([#3388](https://github.com/horizon-rust/horizon/issues/3388)), on/off in Options > Mods. The official mods live in horizon-mods/native/ and are in the registry as native mods. Next: Recipes, native mods on automatically when a player installs one (with a notice about the first build), then the WebAssembly runtime is removed ([#3350](https://github.com/horizon-rust/horizon/issues/3350), [#3351](https://github.com/horizon-rust/horizon/issues/3351), [#3353](https://github.com/horizon-rust/horizon/issues/3353), [#3371](https://github.com/horizon-rust/horizon/issues/3371)).
+
+More: [docs/native-mods.md](docs/native-mods.md)
+
+</details>
+
 #### Mods that run on the server
 
 Mods that run on the server side of a world, so a dedicated server or a LAN world can have mods that react to players joining, chat and blocks being broken or placed, and that add commands.
 
 <details><summary>Technical</summary>
 
-API 0.3, experimental first ([#1833](https://github.com/ludovic111/horizon/issues/1833), in review): the same sandboxed component runs on the server thread and the dedicated server, with world events (block broken or placed, entity spawned or killed, player joined or left), game rules and server commands with typed arguments. The world, item and entity interfaces come after (see 'Mods that read and change the world'). [docs/api/mods.md](docs/api/mods.md), [docs/mods.md](docs/mods.md).
+The same hook points on the server thread and the dedicated server: world events (block broken or placed, entity spawned or killed, player joined or left), game rules and server commands with typed arguments. The earlier WebAssembly API 0.3 ([#1833](https://github.com/horizon-rust/horizon/issues/1833)) is the reference for what to cover.
+
+More: [docs/native-mods.md](docs/native-mods.md)
 
 </details>
 
 #### Screens, input and drawing for mods
 
-Mods will be able to open their own screens and settings pages and react to keys and item use, so bigger mods, such as the Orbital Laser, can run on the normal game.
+Mods will be able to open their own screens and settings pages, react to keys and item use, and draw, so bigger mods, such as the Orbital Laser, run on the normal game.
 
 <details><summary>Technical</summary>
 
-Capability `ui` is in review ([#1864](https://github.com/ludovic111/horizon/issues/1864)): mod-owned screens and a settings page under Options > Mods, built from vanilla's widgets. Still to design: `input` (an item's use, key binds, the crosshair target), `render` (a budgeted draw list on the native shader API) and `world` (changing blocks). Orbital Laser is the acceptance test: it needs all four today through its author's fork (see 'Orbital Laser on the normal game').
-
-More: [docs/mods.md](docs/mods.md)
+On native hook points ([docs/native-mods.md](docs/native-mods.md)): settings pages under Options > Mods and the item panel are there ([#3346](https://github.com/horizon-rust/horizon/issues/3346), [#3435](https://github.com/horizon-rust/horizon/issues/3435)). Next: mod-owned screens built from vanilla's widgets, an item's use, key binds and the crosshair target, and a budgeted draw list on the native shader API. Orbital Laser is the acceptance test.
 
 </details>
 
 #### Tools for people who make mods
 
-Better tools for mod makers: a test runner that needs no game window, templates for each kind of mod, and clear promises about what keeps working from one version to the next.
+Better tools for mod makers: templates for each kind of mod, a test run with no game window, and clear promises about which hook points keep working from one version to the next.
 
 <details><summary>Technical</summary>
 
-`cargo horizon-mod test` runs a mod's test scripts against a fake game snapshot ([#1816](https://github.com/ludovic111/horizon/issues/1816)) and, for server mods, scripted server events ([#1837](https://github.com/ludovic111/horizon/issues/1837)); the content template and the guides are merged ([#1859](https://github.com/ludovic111/horizon/issues/1859), [#1810](https://github.com/ludovic111/horizon/issues/1810), [docs/api/stability.md](docs/api/stability.md)). Left: templates for hud, server and machine mods, typed wrappers in the SDK, a frozen 0.1 compatibility mod that every runtime must load, a CI check that fails when a stable reference entry is removed without a new major version, and the SDK on crates.io once the API is stable.
+Native mod template and the content mod template (horizon-mods), `native.py check` that applies mods on a chosen Horizon and builds them together, a weekly check of every official mod on the newest Nightly. Left: a versioned list of stable hook points (NATIVE_HOOKS_API), a test runner without a window, and docs on the site for native mods.
 
-More: [https://playhorizon.dev/docs/test-a-mod](https://playhorizon.dev/docs/test-a-mod)
+More: [#3388](https://github.com/horizon-rust/horizon/issues/3388) · [docs/native-mods.md](docs/native-mods.md)
 
 </details>
 
@@ -146,7 +158,7 @@ Single player now runs a small server in the background, as vanilla does. We are
 
 <details><summary>Technical</summary>
 
-Since [#1514](https://github.com/ludovic111/horizon/issues/1514) single player runs on the server thread (`game/integrated.rs`) and the window joins it as a client; `--in-frame` keeps the old path. The open `[server-thread]` issues list the gaps. In review: a tool that changes a block ends the click ([#1797](https://github.com/ludovic111/horizon/issues/1797)), potions keep their potion over the connection ([#1796](https://github.com/ludovic111/horizon/issues/1796)), mobs' aggression and arm swings ([#1802](https://github.com/ludovic111/horizon/issues/1802)). [docs/server-levels.md](docs/server-levels.md).
+Since [#1514](https://github.com/horizon-rust/horizon/issues/1514) single player runs on the server thread (`game/integrated.rs`) and the window joins it as a client; `--in-frame` keeps the old path. The open `[server-thread]` issues list the gaps. In review: a tool that changes a block ends the click ([#1797](https://github.com/horizon-rust/horizon/issues/1797)), potions keep their potion over the connection ([#1796](https://github.com/horizon-rust/horizon/issues/1796)), mobs' aggression and arm swings ([#1802](https://github.com/horizon-rust/horizon/issues/1802)). [docs/server-levels.md](docs/server-levels.md).
 
 </details>
 
@@ -156,7 +168,7 @@ Item names, container titles and server messages follow the language you pick, a
 
 <details><summary>Technical</summary>
 
-Translatable components resolved through the selected language for items, containers and server text ([#1806](https://github.com/ludovic111/horizon/issues/1806)), on top of the bundled languages the prepared resources carry ([#1594](https://github.com/ludovic111/horizon/issues/1594)). Left: the client's own screens ([#1672](https://github.com/ludovic111/horizon/issues/1672)) and the main menu with zh_cn ([#1774](https://github.com/ludovic111/horizon/issues/1774)).
+Translatable components resolved through the selected language for items, containers and server text ([#1806](https://github.com/horizon-rust/horizon/issues/1806)), on top of the bundled languages the prepared resources carry ([#1594](https://github.com/horizon-rust/horizon/issues/1594)). Left: the client's own screens ([#1672](https://github.com/horizon-rust/horizon/issues/1672)) and the main menu with zh_cn ([#1774](https://github.com/horizon-rust/horizon/issues/1774)).
 
 </details>
 
@@ -166,9 +178,9 @@ After you throw an ender pearl, its slot should show the cooldown sweeping away,
 
 <details><summary>Technical</summary>
 
-Vanilla draws `ItemCooldowns`' percent as a white overlay over the slot (`GuiGraphicsExtractor.itemDecorations` and `itemCooldown`) in the hotbar and in inventories. Issue [#1763](https://github.com/ludovic111/horizon/issues/1763).
+Vanilla draws `ItemCooldowns`' percent as a white overlay over the slot (`GuiGraphicsExtractor.itemDecorations` and `itemCooldown`) in the hotbar and in inventories. Issue [#1763](https://github.com/horizon-rust/horizon/issues/1763).
 
-More: [#1933](https://github.com/ludovic111/horizon/issues/1933)
+More: [#1933](https://github.com/horizon-rust/horizon/issues/1933)
 
 </details>
 
@@ -178,9 +190,9 @@ The Hidden and Commands Only chat settings should hide chat, and team prefixes s
 
 <details><summary>Technical</summary>
 
-Vanilla checks `ChatVisiblity` before it delivers chat and system messages ([#1376](https://github.com/ludovic111/horizon/issues/1376)), and chat uses the team-formatted display name ([#1378](https://github.com/ludovic111/horizon/issues/1378)). Both issues have exact steps to reproduce.
+Vanilla checks `ChatVisiblity` before it delivers chat and system messages ([#1376](https://github.com/horizon-rust/horizon/issues/1376)), and chat uses the team-formatted display name ([#1378](https://github.com/horizon-rust/horizon/issues/1378)). Both issues have exact steps to reproduce.
 
-More: [#1932](https://github.com/ludovic111/horizon/issues/1932) · [#1841](https://github.com/ludovic111/horizon/issues/1841)
+More: [#1932](https://github.com/horizon-rust/horizon/issues/1932) · [#1841](https://github.com/horizon-rust/horizon/issues/1841)
 
 </details>
 
@@ -190,9 +202,9 @@ The mouse pointer should turn into a pointing hand over menu buttons, as in vani
 
 <details><summary>Technical</summary>
 
-26.3's `AbstractWidget` asks for a cursor from `CursorTypes` when it is hovered; winit's `CursorIcon::Pointer` gives the same shape. Issue [#1347](https://github.com/ludovic111/horizon/issues/1347).
+26.3's `AbstractWidget` asks for a cursor from `CursorTypes` when it is hovered; winit's `CursorIcon::Pointer` gives the same shape. Issue [#1347](https://github.com/horizon-rust/horizon/issues/1347).
 
-More: [#1897](https://github.com/ludovic111/horizon/issues/1897)
+More: [#1897](https://github.com/horizon-rust/horizon/issues/1897)
 
 </details>
 
@@ -202,9 +214,9 @@ Ctrl+Backspace should delete a whole word in the creative search, and every list
 
 <details><summary>Technical</summary>
 
-`EditBox` deletes by word with Ctrl ([#1764](https://github.com/ludovic111/horizon/issues/1764)); the Game Rules and Statistics lists' scroll bars can't be dragged ([#1782](https://github.com/ludovic111/horizon/issues/1782), after [#978](https://github.com/ludovic111/horizon/issues/978)).
+`EditBox` deletes by word with Ctrl ([#1764](https://github.com/horizon-rust/horizon/issues/1764)); the Game Rules and Statistics lists' scroll bars can't be dragged ([#1782](https://github.com/horizon-rust/horizon/issues/1782), after [#978](https://github.com/horizon-rust/horizon/issues/978)).
 
-More: [#1884](https://github.com/ludovic111/horizon/issues/1884) · [#1931](https://github.com/ludovic111/horizon/issues/1931)
+More: [#1884](https://github.com/horizon-rust/horizon/issues/1884) · [#1931](https://github.com/horizon-rust/horizon/issues/1931)
 
 </details>
 
@@ -214,9 +226,9 @@ Chickens should flap their wings while they fall, not stand still in the air.
 
 <details><summary>Technical</summary>
 
-Vanilla's `Chicken.aiStep` updates `flap` and `flapSpeed` when the chicken isn't on the ground, and the model's wings follow them. Issue [#1706](https://github.com/ludovic111/horizon/issues/1706).
+Vanilla's `Chicken.aiStep` updates `flap` and `flapSpeed` when the chicken isn't on the ground, and the model's wings follow them. Issue [#1706](https://github.com/horizon-rust/horizon/issues/1706).
 
-More: [#1892](https://github.com/ludovic111/horizon/issues/1892)
+More: [#1892](https://github.com/horizon-rust/horizon/issues/1892)
 
 </details>
 
@@ -228,9 +240,9 @@ Shader packs were removed and are being rebuilt from scratch. They come back, of
 
 <details><summary>Technical</summary>
 
-A clean-room rewrite in `horizon-shaderpack`, from the packs' public format documentation only: reading packs, the preprocessor and `.properties` files are merged ([#1584](https://github.com/ludovic111/horizon/issues/1584), [#1585](https://github.com/ludovic111/horizon/issues/1585), [#1586](https://github.com/ludovic111/horizon/issues/1586)); translating programs to WGSL through naga, buffers, uniforms and the terrain, entity, sky, weather and hand stages are in review ([#1698](https://github.com/ludovic111/horizon/issues/1698) to [#1801](https://github.com/ludovic111/horizon/issues/1801)).
+A clean-room rewrite in `horizon-shaderpack`, from the packs' public format documentation only: reading packs, the preprocessor and `.properties` files are merged ([#1584](https://github.com/horizon-rust/horizon/issues/1584), [#1585](https://github.com/horizon-rust/horizon/issues/1585), [#1586](https://github.com/horizon-rust/horizon/issues/1586)); translating programs to WGSL through naga, buffers, uniforms and the terrain, entity, sky, weather and hand stages are in review ([#1698](https://github.com/horizon-rust/horizon/issues/1698) to [#1801](https://github.com/horizon-rust/horizon/issues/1801)).
 
-More: [#1561](https://github.com/ludovic111/horizon/issues/1561) · [#1771](https://github.com/ludovic111/horizon/issues/1771) · [#1786](https://github.com/ludovic111/horizon/issues/1786)
+More: [#1561](https://github.com/horizon-rust/horizon/issues/1561) · [#1771](https://github.com/horizon-rust/horizon/issues/1771) · [#1786](https://github.com/horizon-rust/horizon/issues/1786)
 
 </details>
 
@@ -240,7 +252,21 @@ Horizon's own way to make shader packs, with tools to write and test them. Every
 
 <details><summary>Technical</summary>
 
-`horizon-shader-api` (API 0.1, experimental): WGSL stages with typed inputs inside the renderer's passes, options as WGSL override constants, and the `horizon-shader new|check|pack` tool with templates and the example pack Golden Hour. Merged: the check every pack passes ([#1820](https://github.com/ludovic111/horizon/issues/1820)) and the tool, templates and guide ([#1822](https://github.com/ludovic111/horizon/issues/1822)). In review: the post stage running in the game with hot reload ([#1861](https://github.com/ludovic111/horizon/issues/1861)), the sky stage ([#1863](https://github.com/ludovic111/horizon/issues/1863)) and registry checks that use the game's own check ([#1855](https://github.com/ludovic111/horizon/issues/1855)). Left: the material, lighting and shadow stages, a last-good fallback on reload, a GPU-time overlay per stage and budgets ([docs/shaders.md](docs/shaders.md), [docs/api/shaders.md](docs/api/shaders.md)). The Iris/OptiFine loader is a separate item, 'Shader packs, written again from scratch'.
+`horizon-shader-api` (API 0.1, experimental): WGSL stages with typed inputs inside the renderer's passes, options as WGSL override constants, and the `horizon-shader new|check|pack` tool with templates and the example pack Golden Hour. Merged: the check every pack passes ([#1820](https://github.com/horizon-rust/horizon/issues/1820)) and the tool, templates and guide ([#1822](https://github.com/horizon-rust/horizon/issues/1822)). In review: the post stage running in the game with hot reload ([#1861](https://github.com/horizon-rust/horizon/issues/1861)), the sky stage ([#1863](https://github.com/horizon-rust/horizon/issues/1863)) and registry checks that use the game's own check ([#1855](https://github.com/horizon-rust/horizon/issues/1855)). Left: the material, lighting and shadow stages, a last-good fallback on reload, a GPU-time overlay per stage and budgets ([docs/shaders.md](docs/shaders.md), [docs/api/shaders.md](docs/api/shaders.md)). The Iris/OptiFine loader is a separate item, 'Shader packs, written again from scratch'.
+
+</details>
+
+### Launcher
+
+#### Minecraft Java instances in the launcher
+
+Play the real Java game from the Horizon launcher too: vanilla and modded instances, any version, mods from Modrinth filtered to what fits, and your instances imported from other launchers.
+
+<details><summary>Technical</summary>
+
+For an account that owns the game: any version downloaded with the Java it needs ([#3406](https://github.com/horizon-rust/horizon/issues/3406)), Java instances, the version list and the CLI ([#3395](https://github.com/horizon-rust/horizon/issues/3395)), the start command read from the version JSON ([#3419](https://github.com/horizon-rust/horizon/issues/3419)). Next: Play for a Java instance, Fabric and Quilt, then NeoForge and Forge; Modrinth with compatibility filtering and dependencies; imports from Prism, MultiMC, the CurseForge app, the Modrinth App, ATLauncher and the official launcher, each from its documented on-disk format.
+
+More: [#3506](https://github.com/horizon-rust/horizon/issues/3506)
 
 </details>
 
@@ -252,7 +278,7 @@ Your Discord profile can show that you are playing Horizon, with a switch to tur
 
 <details><summary>Technical</summary>
 
-A Discord IPC client on its own thread ([#1787](https://github.com/ludovic111/horizon/issues/1787)) and the presence with its setting ([#1788](https://github.com/ludovic111/horizon/issues/1788)). Merged: it ships with the next release.
+A Discord IPC client on its own thread ([#1787](https://github.com/horizon-rust/horizon/issues/1787)) and the presence with its setting ([#1788](https://github.com/horizon-rust/horizon/issues/1788)). Merged: it ships with the next release.
 
 </details>
 
@@ -264,7 +290,17 @@ Cleaning up Horizon's code: removing what nothing uses and making it quicker to
 
 <details><summary>Technical</summary>
 
-A review of the whole tree: dead code and stubs removed ([#1432](https://github.com/ludovic111/horizon/issues/1432), [#1658](https://github.com/ludovic111/horizon/issues/1658)), one probe binary per crate ([#1453](https://github.com/ludovic111/horizon/issues/1453), [#1454](https://github.com/ludovic111/horizon/issues/1454)), shared harness helpers ([#1448](https://github.com/ludovic111/horizon/issues/1448)), clippy clean on the whole tree ([#1707](https://github.com/ludovic111/horizon/issues/1707)). [docs/architecture.md](docs/architecture.md) maps each feature to its files and harnesses.
+A review of the whole tree: dead code and stubs removed ([#1432](https://github.com/horizon-rust/horizon/issues/1432), [#1658](https://github.com/horizon-rust/horizon/issues/1658)), one probe binary per crate ([#1453](https://github.com/horizon-rust/horizon/issues/1453), [#1454](https://github.com/horizon-rust/horizon/issues/1454)), shared harness helpers ([#1448](https://github.com/horizon-rust/horizon/issues/1448)), clippy clean on the whole tree ([#1707](https://github.com/horizon-rust/horizon/issues/1707)). [docs/architecture.md](docs/architecture.md) maps each feature to its files and harnesses.
+
+</details>
+
+#### Every vanilla method, tracked
+
+A public list of every method of the Java game and where Horizon does it, so anyone can see what is ported, what is missing and pick something to fix.
+
+<details><summary>Technical</summary>
+
+[tools/port_ledger.py](tools/port_ledger.py) and tools/port_map/ ([#3139](https://github.com/horizon-rust/horizon/issues/3139)): every 26.3 method outside the skipped packages has a verdict (port, inline, missing, skip, trivial), linked to the harnesses that cover it ([#3526](https://github.com/horizon-rust/horizon/issues/3526)), with one tracking issue per area. Bug fixes start from it (.claude/skills/vanilla-parity).
 
 </details>
 
@@ -278,7 +314,7 @@ New public numbers comparing Horizon with vanilla on many kinds of computers, me
 
 <details><summary>Technical</summary>
 
-Redo the comparison after the current performance work ([#1073](https://github.com/ludovic111/horizon/issues/1073)); reliability, coverage and presentation ([#1346](https://github.com/ludovic111/horizon/issues/1346)); a scene must count as loaded only once its first chunk arrives ([#1749](https://github.com/ludovic111/horizon/issues/1749)). Next: a performance history across releases (an automatic comparison of each release with the last, on a timeline), more report fields (server TPS and MSPT, power, battery drain, temperature, throttling) and more hardware (a MacBook on battery, low-end laptops, community reports). Players' reports come in through `--benchmark` and `horizon-launcher data benchmark` ([docs/benchmark.md](docs/benchmark.md)).
+Redo the comparison after the current performance work ([#1073](https://github.com/horizon-rust/horizon/issues/1073)); reliability, coverage and presentation ([#1346](https://github.com/horizon-rust/horizon/issues/1346)); a scene must count as loaded only once its first chunk arrives ([#1749](https://github.com/horizon-rust/horizon/issues/1749)). Next: a performance history across releases (an automatic comparison of each release with the last, on a timeline), more report fields (server TPS and MSPT, power, battery drain, temperature, throttling) and more hardware (a MacBook on battery, low-end laptops, community reports). Players' reports come in through `--benchmark` and `horizon-launcher data benchmark` ([docs/benchmark.md](docs/benchmark.md)).
 
 </details>
 
@@ -288,7 +324,7 @@ Creating a world and joining it should be quick even on a four-thread laptop, wh
 
 <details><summary>Technical</summary>
 
-Cut the per-column generation cost (noise sampling, surface rules, aquifers) and the lock convoy on structure starts, and leave one core free for the rest of the game as vanilla does ([#1760](https://github.com/ludovic111/horizon/issues/1760) and [#1778](https://github.com/ludovic111/horizon/issues/1778), in review, are listed under 'Steady frames at long render distances'). Still to profile on small CPUs: the first seconds of a fresh world deliver no chunk, and fluids remesh for about a minute after loading. Measured with `tools/perf_bench.py` ([docs/benchmark.md](docs/benchmark.md), [docs/profiling.md](docs/profiling.md)).
+Cut the per-column generation cost (noise sampling, surface rules, aquifers) and the lock convoy on structure starts, and leave one core free for the rest of the game as vanilla does ([#1760](https://github.com/horizon-rust/horizon/issues/1760) and [#1778](https://github.com/horizon-rust/horizon/issues/1778), in review, are listed under 'Steady frames at long render distances'). Still to profile on small CPUs: the first seconds of a fresh world deliver no chunk, and fluids remesh for about a minute after loading. Measured with `tools/perf_bench.py` ([docs/benchmark.md](docs/benchmark.md), [docs/profiling.md](docs/profiling.md)).
 
 </details>
 
@@ -320,7 +356,7 @@ Draw the game at a lower resolution and sharpen it to your screen's size, in the
 
 <details><summary>Technical</summary>
 
-A render-scale setting below the window size with an upscaler of our own that runs on every wgpu backend. Proof: frame time against native resolution on integrated GPUs, and screenshots for image quality. Issue [#1403](https://github.com/ludovic111/horizon/issues/1403).
+A render-scale setting below the window size with an upscaler of our own that runs on every wgpu backend. Proof: frame time against native resolution on integrated GPUs, and screenshots for image quality. Issue [#1403](https://github.com/horizon-rust/horizon/issues/1403).
 
 </details>
 
@@ -330,7 +366,7 @@ Several smaller speed-ups, each measured: idle block entities that sleep, cheape
 
 <details><summary>Technical</summary>
 
-Block entities and hoppers that skip work when idle (the hopper item scan is already skipped when no item is near); a particle frustum test first (also a parity gap), then particle quads built on the GPU; jigsaw shortcuts that skip blocked connectors and pool elements known not to fit, with layouts unchanged (trial chambers and ancient cities first); batched raw mouse input on Windows for 8000 Hz mice; a better atlas packer for huge resource packs (a 64x pack builds a 704 MiB atlas for 452 MiB of textures); sign-heavy scenes ([#1461](https://github.com/ludovic111/horizon/issues/1461)). Profile first, keep what pays, show before and after numbers.
+Block entities and hoppers that skip work when idle (the hopper item scan is already skipped when no item is near); a particle frustum test first (also a parity gap), then particle quads built on the GPU; jigsaw shortcuts that skip blocked connectors and pool elements known not to fit, with layouts unchanged (trial chambers and ancient cities first); batched raw mouse input on Windows for 8000 Hz mice; a better atlas packer for huge resource packs (a 64x pack builds a 704 MiB atlas for 452 MiB of textures); sign-heavy scenes ([#1461](https://github.com/horizon-rust/horizon/issues/1461)). Profile first, keep what pays, show before and after numbers.
 
 More: [docs/profiling.md](docs/profiling.md)
 
@@ -364,7 +400,7 @@ Making mods that add machines, magic and mobs work in Horizon, in steps, startin
 
 <details><summary>Technical</summary>
 
-333 of the 496 mods in a big pack (ATM10) contain code. Issue [#1854](https://github.com/ludovic111/horizon/issues/1854) ranks the API gaps (ticking block entities, networking, rendering, menus, inventories) that unlock them in tiers, with machines first as the recommended path and a furnace ported tick for tick as proof. The first API step is a draft ([#1189](https://github.com/ludovic111/horizon/issues/1189), see 'Machines and blocks with inventories'). The path isn't started yet ([docs/modpacks.md](docs/modpacks.md)).
+333 of the 496 mods in a big pack (ATM10) contain code. Issue [#1854](https://github.com/horizon-rust/horizon/issues/1854) ranks the API gaps (ticking block entities, networking, rendering, menus, inventories) that unlock them in tiers, with machines first as the recommended path and a furnace ported tick for tick as proof. The first API step is a draft ([#1189](https://github.com/horizon-rust/horizon/issues/1189), see 'Machines and blocks with inventories'). The path isn't started yet ([docs/modpacks.md](docs/modpacks.md)).
 
 </details>
 
@@ -386,7 +422,7 @@ Set up Horizon, a server first, without Java on your computer: published tables
 
 <details><summary>Technical</summary>
 
-Today `horizon-prepare` runs Mojang's exporters with Java. Issue [#1750](https://github.com/ludovic111/horizon/issues/1750) proposes publishing the computed version tables once from CI and assembling the rest locally from the player's own jar and assets, provided the tables hold no Mojang content; a contributor offered a pull request, and it would help phones too. A server-only prepare from `server.jar` alone is the first step ([docs/server.md](docs/server.md)).
+Today `horizon-prepare` runs Mojang's exporters with Java. Issue [#1750](https://github.com/horizon-rust/horizon/issues/1750) proposes publishing the computed version tables once from CI and assembling the rest locally from the player's own jar and assets, provided the tables hold no Mojang content; a contributor offered a pull request, and it would help phones too. A server-only prepare from `server.jar` alone is the first step ([docs/server.md](docs/server.md)).
 
 </details>
 
@@ -406,7 +442,7 @@ Smoother hosting: a real Windows service, a backup before every update, backups
 
 <details><summary>Technical</summary>
 
-A Windows service wrapper instead of the logon scheduled task; `backups.before_update`; hot reload of config for view distance and the message of the day (needs engine support); backups that keep world and player state ([#1808](https://github.com/ludovic111/horizon/issues/1808), a contributor's draft, in review). [docs/hosting.md](docs/hosting.md), docs/server.md.
+A Windows service wrapper instead of the logon scheduled task; `backups.before_update`; hot reload of config for view distance and the message of the day (needs engine support); backups that keep world and player state ([#1808](https://github.com/horizon-rust/horizon/issues/1808), a contributor's draft, in review). [docs/hosting.md](docs/hosting.md), docs/server.md.
 
 </details>
 
@@ -444,6 +480,16 @@ A player's idea (#horizon-ideas). `horizon-server` already runs headless; left:
 
 </details>
 
+#### Ready-made setups for hosting panels
+
+Install a Horizon server from the panels hosts use, such as Pterodactyl and AMP, the usual way for each panel.
+
+<details><summary>Technical</summary>
+
+Asked in the suggestion queue for Pterodactyl eggs and AMP templates. Builds on the one-command install ('A server you install with one command') and horizon-server's server.toml ([docs/hosting.md](docs/hosting.md)).
+
+</details>
+
 ### Mods and API
 
 #### Mods that read and change the world
@@ -452,9 +498,9 @@ Mods that can see and change blocks, read inventories and items, and find and af
 
 <details><summary>Technical</summary>
 
-After server mods: read blocks, states and biomes in loaded chunks and change them through the server's block log, so clients and the parity harnesses see vanilla's updates; the player's inventory, held item, open container and item stacks with components; entity queries near a position, a safe subset of entity data and data-driven mod entity types. Snapshots and batched calls per tick, never per-block host calls in hot paths. [docs/api/mods.md](docs/api/mods.md) ('Not there yet').
+Hook points for reading blocks, states and biomes and changing them through the server's block log, so clients and the parity harnesses see vanilla's updates; the player's inventory and item stacks with components; entity queries near a position. Batched per tick, never per-block calls in hot paths.
 
-More: [docs/modpacks.md](docs/modpacks.md)
+More: [docs/native-mods.md](docs/native-mods.md) · [docs/modpacks.md](docs/modpacks.md)
 
 </details>
 
@@ -464,17 +510,7 @@ Mods that add machines: blocks that tick, hold items and have their own menus. T
 
 <details><summary>Technical</summary>
 
-Block entities and menus: ticking machines with slots, server menu logic and the menu protocol to clients, energy, item and fluid transfer, data attachments, accessory slots and custom recipe types, with a typed client and server channel and typed config beside them. A draft ([#1189](https://github.com/ludovic111/horizon/issues/1189)) proves a furnace ported tick for tick and holds the ATM10 code-mods plan; the design is redone through the API policy before it merges ([docs/modpacks.md](docs/modpacks.md), docs/api/stability.md).
-
-</details>
-
-#### Lua and other languages for mods
-
-Write mods as Lua scripts, in the style of KubeJS, with no compiler, and later in other languages that pass the tests. Every language runs in the same sandbox.
-
-<details><summary>Technical</summary>
-
-Lua first: Horizon ships a Lua interpreter that is itself a WebAssembly mod, and a script mod's manifest names it and the capabilities it uses, so a script can do exactly what a compiled mod with the same manifest can, with hot reload of `main.lua`. Then C, C++, Zig, Go (TinyGo), AssemblyScript and JavaScript or TypeScript are measured against Rust on the same tick-heavy example, and each is supported only with a template, an example and a CI test. [docs/api/mods.md](docs/api/mods.md) ('Ways in').
+Block entities and menus: ticking machines with slots, server menu logic and the menu protocol to clients, energy, item and fluid transfer, data attachments, accessory slots and custom recipe types, with a typed client and server channel and typed config beside them. A draft ([#1189](https://github.com/horizon-rust/horizon/issues/1189)) proves a furnace ported tick for tick and holds the ATM10 code-mods plan; the design is redone through the API policy before it merges ([docs/modpacks.md](docs/modpacks.md), docs/api/stability.md).
 
 </details>
 
@@ -486,7 +522,7 @@ Pistons and slime blocks will push players, mobs and items as in vanilla. Today
 
 <details><summary>Technical</summary>
 
-Port `PistonMovingBlockEntity.moveCollidedEntities` and `moveStuckEntities` (honey), the slime bounce and `Entity.limitPistonMovement` for `MoverType.PISTON`, in single player and for a server's players. Issues [#1496](https://github.com/ludovic111/horizon/issues/1496), [#1609](https://github.com/ludovic111/horizon/issues/1609), [#1608](https://github.com/ludovic111/horizon/issues/1608), [#1704](https://github.com/ludovic111/horizon/issues/1704), [#1758](https://github.com/ludovic111/horizon/issues/1758).
+Port `PistonMovingBlockEntity.moveCollidedEntities` and `moveStuckEntities` (honey), the slime bounce and `Entity.limitPistonMovement` for `MoverType.PISTON`, in single player and for a server's players. Issues [#1496](https://github.com/horizon-rust/horizon/issues/1496), [#1609](https://github.com/horizon-rust/horizon/issues/1609), [#1608](https://github.com/horizon-rust/horizon/issues/1608), [#1704](https://github.com/horizon-rust/horizon/issues/1704), [#1758](https://github.com/horizon-rust/horizon/issues/1758).
 
 </details>
 
@@ -506,7 +542,7 @@ Villages and fights behaving as in vanilla: iron golems defending villages, vill
 
 <details><summary>Technical</summary>
 
-Villages: iron golem village goals, villager memories across saves, villager age, job-site claiming on dedicated servers, flower offers ([#1639](https://github.com/ludovic111/horizon/issues/1639) is one report). Combat: the mobs' `attack_knockback` attribute, mace smash logic, the hit knockback source on the host, the fire burnout biome tag. Each is checked against vanilla by a harness ([docs/rust-parity.md](docs/rust-parity.md)).
+Villages: iron golem village goals, villager memories across saves, villager age, job-site claiming on dedicated servers, flower offers ([#1639](https://github.com/horizon-rust/horizon/issues/1639) is one report). Combat: the mobs' `attack_knockback` attribute, mace smash logic, the hit knockback source on the host, the fire burnout biome tag. Each is checked against vanilla by a harness ([docs/rust-parity.md](docs/rust-parity.md)).
 
 </details>
 
@@ -516,7 +552,7 @@ Pick the speakers or headphones Horizon plays through, in Music & Sounds.
 
 <details><summary>Technical</summary>
 
-An output device list in Music & Sounds, falling back to the system default. [#1035](https://github.com/ludovic111/horizon/issues/1035) started it: a player on an older Windows computer had no sound at all, and a device choice is how such cases are found and fixed.
+An output device list in Music & Sounds, falling back to the system default. [#1035](https://github.com/horizon-rust/horizon/issues/1035) started it: a player on an older Windows computer had no sound at all, and a device choice is how such cases are found and fixed.
 
 </details>
 
@@ -536,15 +572,13 @@ More: [docs/shaders.md](docs/shaders.md)
 
 ### Launcher
 
-#### Microsoft sign-in (coming soon)
+#### A new launcher design
 
-Coming soon: sign in with your Microsoft account to play on online-mode servers. The code is ready; it waits for Microsoft's approval.
+A redesigned launcher: every button where you expect it, the fewest clicks to play, add an instance or add mods, smooth animations, and instant startup.
 
 <details><summary>Technical</summary>
 
-Device-code sign-in in the launcher and online-mode login in the client ([docs/microsoft-account.md](docs/microsoft-account.md)). It is turned on by setting the app's client id once Minecraft API access is approved; until then the launcher shows "Coming soon".
-
-More: [#1270](https://github.com/ludovic111/horizon/issues/1270)
+Based on the site concept by the Team (Bricolage Grotesque, a night sky and an animated pixel sunset). Screens and flows are designed first, then small PRs; tokens in [crates/horizon-theme](crates/horizon-theme) and rules in [docs/design-system.md](docs/design-system.md), the game's vanilla look unchanged. Measured before and after: startup, frame time and idle CPU/GPU, reduced motion honoured. Mods screens separate Horizon native mods from Java mods; a running instance can be stopped from the launcher.
 
 </details>
 
@@ -566,7 +600,7 @@ Builds of the game and the launcher for Macs with an Intel processor.
 
 <details><summary>Technical</summary>
 
-x86_64 game and launcher builds, picked per processor ([#1171](https://github.com/ludovic111/horizon/issues/1171)). Before it ships it needs a run on a real Intel Mac: Rosetta on Apple Silicon only proves the CPU code. Requests: [#1161](https://github.com/ludovic111/horizon/issues/1161), [#1792](https://github.com/ludovic111/horizon/issues/1792).
+x86_64 game and launcher builds, picked per processor ([#1171](https://github.com/horizon-rust/horizon/issues/1171)). Before it ships it needs a run on a real Intel Mac: Rosetta on Apple Silicon only proves the CPU code. Requests: [#1161](https://github.com/horizon-rust/horizon/issues/1161), [#1792](https://github.com/horizon-rust/horizon/issues/1792).
 
 </details>
 
@@ -576,7 +610,7 @@ Fixes for Linux desktops that use Wayland and Hyprland: fullscreen, the clipboar
 
 <details><summary>Technical</summary>
 
-Open: the GUI Scale is clamped to 2 after a restart under Hyprland, while XWayland keeps it ([#1866](https://github.com/ludovic111/horizon/issues/1866)). Earlier reports covered fullscreen dropping on menu clicks, the clipboard and a white overlay ([#1007](https://github.com/ludovic111/horizon/issues/1007), closed). Checked on a real Wayland session.
+Open: the GUI Scale is clamped to 2 after a restart under Hyprland, while XWayland keeps it ([#1866](https://github.com/horizon-rust/horizon/issues/1866)). Earlier reports covered fullscreen dropping on menu clicks, the clipboard and a white overlay ([#1007](https://github.com/horizon-rust/horizon/issues/1007), closed). Checked on a real Wayland session.
 
 </details>
 
@@ -626,7 +660,7 @@ Safer releases: changes to the release machinery need the owner's review, and AI
 
 <details><summary>Technical</summary>
 
-`.github/CODEOWNERS` lists the workflows, the release and signing tools, the update-checking code and the installers ([#1015](https://github.com/ludovic111/horizon/issues/1015)); the branch protection that makes it count waits for the `horizon-agent` GitHub App, which reads and writes code, pull requests and issues but can't change settings, workflows, secrets or members, and whose tokens last an hour. It needs the owner to create the App and switch the protection on ([docs/security.md](docs/security.md)).
+`.github/CODEOWNERS` lists the workflows, the release and signing tools, the update-checking code and the installers ([#1015](https://github.com/horizon-rust/horizon/issues/1015)); the branch protection that makes it count waits for the `horizon-agent` GitHub App, which reads and writes code, pull requests and issues but can't change settings, workflows, secrets or members, and whose tokens last an hour. It needs the owner to create the App and switch the protection on ([docs/security.md](docs/security.md)).
 
 </details>
 
@@ -636,7 +670,7 @@ Every download Horizon makes is checked against the project's signature, includi
 
 <details><summary>Technical</summary>
 
-Releases carry signed checksums, and the launcher and `horizon-server update` refuse anything unsigned ([#1011](https://github.com/ludovic111/horizon/issues/1011), [#1014](https://github.com/ludovic111/horizon/issues/1014)). Left: the first install through `install.sh` and `install.ps1` still trusts only the checksum GitHub publishes, because verifying Ed25519 signatures needs OpenSSL 3, which macOS doesn't ship ([docs/security.md](docs/security.md)).
+Releases carry signed checksums, and the launcher and `horizon-server update` refuse anything unsigned ([#1011](https://github.com/horizon-rust/horizon/issues/1011), [#1014](https://github.com/horizon-rust/horizon/issues/1014)). Left: the first install through `install.sh` and `install.ps1` still trusts only the checksum GitHub publishes, because verifying Ed25519 signatures needs OpenSSL 3, which macOS doesn't ship ([docs/security.md](docs/security.md)).
 
 </details>
 
@@ -650,7 +684,7 @@ Far terrain drawn from the world you really built and explored, caves and builds
 
 <details><summary>Technical</summary>
 
-Keep a 3D mip store on disk built from real chunks, drawn by the GPU beside the seed preview for areas nobody has visited. Written from scratch and measured before it is kept. Builds on Far Detail and the far-terrain levels of detail already shipped; the open work on them is [#718](https://github.com/ludovic111/horizon/issues/718).
+Keep a 3D mip store on disk built from real chunks, drawn by the GPU beside the seed preview for areas nobody has visited. Written from scratch and measured before it is kept. Builds on Far Detail and the far-terrain levels of detail already shipped; the open work on them is [#718](https://github.com/horizon-rust/horizon/issues/718).
 
 </details>
 
@@ -692,7 +726,7 @@ Run Java mods that nobody has rewritten for Horizon yet, through a bridge or a c
 
 <details><summary>Technical</summary>
 
-Earlier research ([#527](https://github.com/ludovic111/horizon/issues/527), closed) found that Java mods can't simply run, because they call Minecraft's own classes. Options to look at again: a jar-to-WebAssembly backend, or a bridge for simple Fabric mods. Whatever is chosen has to run inside the same sandbox and capability checks as native mods.
+Earlier research ([#527](https://github.com/horizon-rust/horizon/issues/527), closed) found that Java mods can't simply run, because they call Minecraft's own classes. Options to look at again: a jar-to-WebAssembly backend, or a bridge for simple Fabric mods. Whatever is chosen has to run inside the same sandbox and capability checks as native mods.
 
 </details>
 
@@ -704,7 +738,19 @@ Sign in with other account providers, such as Ely.by or any Yggdrasil-compatible
 
 <details><summary>Technical</summary>
 
-Issue [#1270](https://github.com/ludovic111/horizon/issues/1270) asks for Ely.by and Yggdrasil-compatible servers with an account selector in the launcher. It builds on the Microsoft sign-in ([docs/microsoft-account.md](docs/microsoft-account.md)).
+Issue [#1270](https://github.com/horizon-rust/horizon/issues/1270) asks for Ely.by and Yggdrasil-compatible servers with an account selector in the launcher. It builds on the Microsoft sign-in ([docs/microsoft-account.md](docs/microsoft-account.md)).
+
+</details>
+
+#### Join servers on older versions
+
+Join servers that run older Minecraft versions, such as 1.21 or 1.8 PvP servers, from Horizon.
+
+<details><summary>Technical</summary>
+
+Asked often in the suggestion queue. Horizon speaks 26.3's protocol; the path is a native protocol adapter in Rust that translates older versions' packets, not a downloaded Java proxy. Java instances in the launcher already play any version with the real game.
+
+More: [#3023](https://github.com/horizon-rust/horizon/issues/3023)
 
 </details>
 
@@ -720,6 +766,18 @@ Play with Friends joins over an encrypted tunnel with an invite code ([docs/play
 
 ### Mods and API
 
+#### Scripts for mods
+
+Small mods written as scripts, in the style of KubeJS, with no compiler.
+
+<details><summary>Technical</summary>
+
+Waits for native mods to settle: the earlier plan ran Lua inside the WebAssembly sandbox, which is being removed. A script layer over the native hook points is to be designed.
+
+More: [docs/native-mods.md](docs/native-mods.md)
+
+</details>
+
 #### Orbital Laser on the normal game
 
 The community mod Orbital Laser, made for a fork of Horizon, running on the normal game and listed in the registry as the showcase of the mod API.
@@ -732,13 +790,13 @@ A pull request on [https://github.com/Stink-O/orbital-laser](https://github.com/
 
 #### Native versions of popular client mods
 
-Built-in versions of the client mods players ask for: block info on hover, a recipe viewer like JEI, a world map and schematic overlays.
+Built-in versions of the client mods players ask for: block info on hover, a world map, inventory tweaks and schematic overlays.
 
 <details><summary>Technical</summary>
 
-Done as extras: a mod list and menu, a minimap and a zoom ([docs/extras.md](docs/extras.md)). Left: block info tooltips, a recipe viewer (a contributor offered to port JEI if it becomes a native feature), a world map and a schematic overlay. They need the read-only interfaces `inventory-read`, `recipes`, `world-read` and `render` in the mod API, or they go into the game directly.
+Done: a mod list and menu, minimap, zoom, keystrokes, an FPS counter and a recipe viewer, as native mods (horizon-mods/native/). Asked for: an angled world map that shows hills, overhangs and caves, inventory tweaks (drag and scroll to move items), block info tooltips and schematic overlays.
 
-More: [docs/mods.md](docs/mods.md)
+More: [docs/extras.md](docs/extras.md) · [docs/native-mods.md](docs/native-mods.md)
 
 </details>
 
@@ -748,7 +806,7 @@ Contraptions and physics like the Create and Aeronautics mods, as a mod for Hori
 
 <details><summary>Technical</summary>
 
-Issue [#805](https://github.com/ludovic111/horizon/issues/805) (porting QOL mods) closed with this answer: it would come as a native Horizon mod on the mod API. It needs server mods, entities and rendering first.
+Issue [#805](https://github.com/horizon-rust/horizon/issues/805) (porting QOL mods) closed with this answer: it would come as a native Horizon mod on the mod API. It needs server mods, entities and rendering first.
 
 </details>
 
@@ -784,13 +842,23 @@ The game side is merged ([docs/controllers.md](docs/controllers.md)): pads read
 
 </details>
 
+#### Splitscreen
+
+Play with a friend on the same screen, each with a controller.
+
+<details><summary>Technical</summary>
+
+Issue [#2054](https://github.com/horizon-rust/horizon/issues/2054); a contributor is working on it. Two local players on the same world, each with their own camera and HUD, built on the server thread's multiplayer.
+
+</details>
+
 #### The full debug screen
 
 Vanilla's complete F3 screen: debug options, a profiler chart, ten-second captures and an atlas dump.
 
 <details><summary>Technical</summary>
 
-Today F3 shows position, chunk, light, biome and FPS ([docs/native-client.md](docs/native-client.md)). Vanilla also has F3+F6 debug options with profiles, F3+1 the profiler pie, F3+L a ten-second capture and F3+S the atlas dump ([#562](https://github.com/ludovic111/horizon/issues/562) asked for the F3 editor).
+Today F3 shows position, chunk, light, biome and FPS ([docs/native-client.md](docs/native-client.md)). Vanilla also has F3+F6 debug options with profiles, F3+1 the profiler pie, F3+L a ten-second capture and F3+S the atlas dump ([#562](https://github.com/horizon-rust/horizon/issues/562) asked for the F3 editor).
 
 </details>
 
@@ -814,7 +882,7 @@ An optional ray-tracing mode for graphics cards that support it (RTX and recent
 
 <details><summary>Technical</summary>
 
-A spike with ray-traced sun shadows, off by default, is a draft ([#1180](https://github.com/ludovic111/horizon/issues/1180)). Reflections, global illumination, Apple M3 and newer if it is cheap, and a performance report per card come after.
+A spike with ray-traced sun shadows, off by default, is a draft ([#1180](https://github.com/horizon-rust/horizon/issues/1180)). Reflections, global illumination, Apple M3 and newer if it is cheap, and a performance report per card come after.
 
 </details>
 
@@ -824,7 +892,7 @@ Output for HDR monitors: brighter highlights and richer colour where your screen
 
 <details><summary>Technical</summary>
 
-Issue [#1441](https://github.com/ludovic111/horizon/issues/1441). Needs a surface format and a tone-mapping path per backend, and tests on real HDR screens on Windows, macOS and Linux.
+Issue [#1441](https://github.com/horizon-rust/horizon/issues/1441). Needs a surface format and a tone-mapping path per backend, and tests on real HDR screens on Windows, macOS and Linux.
 
 </details>
 
@@ -834,7 +902,7 @@ More graphics options: multisample anti-aliasing, anisotropic filtering and an e
 
 <details><summary>Technical</summary>
 
-Not implemented ([docs/graphics.md](docs/graphics.md)). Anisotropic filtering needs linear magnification in wgpu, which blurs close blocks, so close-up sharpness has to be kept first; MSAA would sit beside FXAA; exclusive fullscreen where the backend supports it.
+Not implemented ([docs/graphics.md](docs/graphics.md)). Anisotropic filtering needs linear magnification in wgpu, which blurs close blocks, so close-up sharpness has to be kept first; MSAA would sit beside FXAA, and SMAA or TAA are asked for too; exclusive fullscreen where the backend supports it.
 
 </details>
 
@@ -858,7 +926,19 @@ Game and launcher builds for 64-bit ARM Linux computers.
 
 <details><summary>Technical</summary>
 
-Issue [#1709](https://github.com/ludovic111/horizon/issues/1709): aarch64 builds of the game and the launcher in the release workflow, tested on a real ARM machine with its Vulkan driver. The server build already drops audio and controllers (`--no-default-features`).
+Issue [#1709](https://github.com/horizon-rust/horizon/issues/1709): aarch64 builds of the game and the launcher in the release workflow, tested on a real ARM machine with its Vulkan driver. The server build already drops audio and controllers (`--no-default-features`).
+
+</details>
+
+#### Horizon on Windows ARM64
+
+A native Horizon for Windows on ARM computers, such as Snapdragon laptops.
+
+<details><summary>Technical</summary>
+
+Releases are x64 for Windows and Linux and arm64 for macOS. Needs an aarch64-pc-windows-msvc build in the release workflow and a machine to test on.
+
+More: [docs/release-flow.md](docs/release-flow.md)
 
 </details>
 
@@ -868,7 +948,7 @@ Versions of Horizon for Android, iOS and web browsers. Nothing official yet; con
 
 <details><summary>Technical</summary>
 
-No official build. Android was first closed as not planned, with touch controls, a mobile interface, packaging and loading the player's own assets all missing; the roadmap now includes it, iOS and a WebAssembly build for the browser as long-term goals. First pieces from contributors: `horizon-dualsense` compiling on iOS ([#1813](https://github.com/ludovic111/horizon/issues/1813)) and helper-thread limits on Android ([#1751](https://github.com/ludovic111/horizon/issues/1751)). Preparing without Java ([#1750](https://github.com/ludovic111/horizon/issues/1750)) matters here too. Horizon ships none of Mojang's files on any platform.
+No official build. Android was first closed as not planned, with touch controls, a mobile interface, packaging and loading the player's own assets all missing; the roadmap now includes it, iOS and a WebAssembly build for the browser as long-term goals. First pieces from contributors: `horizon-dualsense` compiling on iOS ([#1813](https://github.com/horizon-rust/horizon/issues/1813)) and helper-thread limits on Android ([#1751](https://github.com/horizon-rust/horizon/issues/1751)). Preparing without Java ([#1750](https://github.com/horizon-rust/horizon/issues/1750)) matters here too. Horizon ships none of Mojang's files on any platform.
 
 </details>
 
@@ -912,7 +992,7 @@ An optional AI teammate you can talk to by voice. It plays beside you, helps or
 
 <details><summary>Technical</summary>
 
-Draft pull requests: the companion ([#1068](https://github.com/ludovic111/horizon/issues/1068)), its safety modes and their evaluation ([#1069](https://github.com/ludovic111/horizon/issues/1069)) and a route that finishes the game ([#1070](https://github.com/ludovic111/horizon/issues/1070)). In the drafts: a companion that follows, fights, mines, crafts, sleeps and respawns; chat and push-to-talk voice, with speech recognition and a choice of voices; presets (very strong, helper, beat the game); a guard model with Clean, Kid and Salty modes; perception levels from Fair to All-knowing; hardware detection with a simple mode and an Advanced tab; local models first, cloud keys optional. The No AI switch is already in the game. Left: the speedrun route doesn't finish the game reliably yet, voices for more languages, and the safety evaluation, which must pass before it ships.
+Draft pull requests: the companion ([#1068](https://github.com/horizon-rust/horizon/issues/1068)), its safety modes and their evaluation ([#1069](https://github.com/horizon-rust/horizon/issues/1069)) and a route that finishes the game ([#1070](https://github.com/horizon-rust/horizon/issues/1070)). In the drafts: a companion that follows, fights, mines, crafts, sleeps and respawns; chat and push-to-talk voice, with speech recognition and a choice of voices; presets (very strong, helper, beat the game); a guard model with Clean, Kid and Salty modes; perception levels from Fair to All-knowing; hardware detection with a simple mode and an Advanced tab; local models first, cloud keys optional. The No AI switch is already in the game. Left: the speedrun route doesn't finish the game reliably yet, voices for more languages, and the safety evaluation, which must pass before it ships.
 
 </details>
 
@@ -938,7 +1018,7 @@ Run Horizon's built-in benchmark and share the report: every new computer makes
 
 <details><summary>Technical</summary>
 
-`horizon-launcher play --arg=--benchmark --arg=standard` writes a JSON report; `horizon-launcher data benchmark <report>` shows what would be sent and uploads it (playhorizon.dev/docs/performance). Results from three installs with the same hardware appear on the Benchmarks page. Example: [#1711](https://github.com/ludovic111/horizon/issues/1711).
+`horizon-launcher play --arg=--benchmark --arg=standard` writes a JSON report; `horizon-launcher data benchmark <report>` shows what would be sent and uploads it (playhorizon.dev/docs/performance). Results from three installs with the same hardware appear on the Benchmarks page. Example: [#1711](https://github.com/horizon-rust/horizon/issues/1711).
 
 More: [https://playhorizon.dev/docs/performance](https://playhorizon.dev/docs/performance)
 
@@ -952,7 +1032,7 @@ Banners in End cities show as plain magenta instead of with their pattern.
 
 <details><summary>Technical</summary>
 
-Compare the banner block entities the End city templates place with vanilla's (`EndCityPieces`, the templates' block entity NBT, `BannerBlockEntity`'s patterns), in `crates/horizon-world/src/worldgen/structure/`. Issue [#1438](https://github.com/ludovic111/horizon/issues/1438); possibly related: [#526](https://github.com/ludovic111/horizon/issues/526).
+Compare the banner block entities the End city templates place with vanilla's (`EndCityPieces`, the templates' block entity NBT, `BannerBlockEntity`'s patterns), in `crates/horizon-world/src/worldgen/structure/`. Issue [#1438](https://github.com/horizon-rust/horizon/issues/1438); possibly related: [#526](https://github.com/horizon-rust/horizon/issues/526).
 
 </details>
 
@@ -962,19 +1042,20 @@ Armour and tools in End city chests should come enchanted, as in vanilla.
 
 <details><summary>Technical</summary>
 
-`loot.rs` implements `enchant_with_levels`: find why the End city chest table's rolls come out bare, and compare them with vanilla's for a few seeds. Issues [#1437](https://github.com/ludovic111/horizon/issues/1437), [#1660](https://github.com/ludovic111/horizon/issues/1660).
+`loot.rs` implements `enchant_with_levels`: find why the End city chest table's rolls come out bare, and compare them with vanilla's for a few seeds. Issues [#1437](https://github.com/horizon-rust/horizon/issues/1437), [#1660](https://github.com/horizon-rust/horizon/issues/1660).
 
 </details>
 
 ## Recently shipped
 
-- **OpenGL for old computers** (v0.2.63): Horizon now starts on old PCs whose graphics card has no Vulkan or DirectX 12 driver: it switches to OpenGL by itself, and Options > Graphics can pick OpenGL by hand. [#1917](https://github.com/ludovic111/horizon/issues/1917) · [#1920](https://github.com/ludovic111/horizon/issues/1920) · [#1936](https://github.com/ludovic111/horizon/issues/1936)
-- **Server resource packs** (v0.2.48): Servers can send you their resource pack: Horizon asks, downloads it and applies it, like vanilla. [#1562](https://github.com/ludovic111/horizon/issues/1562) · [#1569](https://github.com/ludovic111/horizon/issues/1569) · [#1570](https://github.com/ludovic111/horizon/issues/1570)
-- **Single player on its own server thread** (v0.2.39): Single player runs on a server thread, as vanilla does, so the world keeps ticking smoothly while the window draws. [#1514](https://github.com/ludovic111/horizon/issues/1514) · [docs/server-levels.md](docs/server-levels.md)
-- **GPU occlusion culling on Macs** (v0.2.17): On Macs the GPU now skips terrain hidden behind hills and caves: 8 to 48% more frames per second at 32 chunks on an M4 Pro. [#1434](https://github.com/ludovic111/horizon/issues/1434)
-- **Animated textures on the GPU** (v0.2.5): Water, lava and other animated blocks are now animated by the graphics card: 1.7 to 2.4 times better 1% lows on Intel graphics. [#1239](https://github.com/ludovic111/horizon/issues/1239)
-- **Far Detail for integrated graphics** (v0.2.5): An optional Reduced setting for far terrain, suggested on integrated graphics, that saves 2 to 4 ms of GPU time per frame. [#1199](https://github.com/ludovic111/horizon/issues/1199) · [#1029](https://github.com/ludovic111/horizon/issues/1029)
-- **The launcher's mod browser** (launcher@0.2.0): Search Modrinth for mods, modpacks and resource packs from the launcher; it says before installing what works in Horizon. [#1154](https://github.com/ludovic111/horizon/issues/1154) · [#1242](https://github.com/ludovic111/horizon/issues/1242) · [#1243](https://github.com/ludovic111/horizon/issues/1243) · [#1246](https://github.com/ludovic111/horizon/issues/1246) · [docs/mod-browser.md](docs/mod-browser.md)
-- **A blocky, Minecraft-like launcher** (launcher@0.2.0): The launcher got a new blocky look in Horizon's purple, in dark and light. [#1269](https://github.com/ludovic111/horizon/issues/1269) · [docs/design-system.md](docs/design-system.md)
-- **Dynamic lights** (v2026.10.22): An optional extra: torches you hold, drop or set on fire light up what is around them. [#1162](https://github.com/ludovic111/horizon/issues/1162)
-- **Host a server from the launcher** (launcher-v0.15.0): The launcher's Servers page creates, starts, backs up and updates a Horizon server with buttons, and invites friends. [#1026](https://github.com/ludovic111/horizon/issues/1026) · [docs/hosting.md](docs/hosting.md)
+- **Microsoft sign-in** (launcher@0.2.17): Sign in with your Microsoft account in the launcher to play on online-mode servers. [docs/microsoft-account.md](docs/microsoft-account.md) · [#2879](https://github.com/horizon-rust/horizon/issues/2879)
+- **OpenGL for old computers** (v0.2.63): Horizon now starts on old PCs whose graphics card has no Vulkan or DirectX 12 driver: it switches to OpenGL by itself, and Options > Graphics can pick OpenGL by hand. [#1917](https://github.com/horizon-rust/horizon/issues/1917) · [#1920](https://github.com/horizon-rust/horizon/issues/1920) · [#1936](https://github.com/horizon-rust/horizon/issues/1936)
+- **Server resource packs** (v0.2.48): Servers can send you their resource pack: Horizon asks, downloads it and applies it, like vanilla. [#1562](https://github.com/horizon-rust/horizon/issues/1562) · [#1569](https://github.com/horizon-rust/horizon/issues/1569) · [#1570](https://github.com/horizon-rust/horizon/issues/1570)
+- **Single player on its own server thread** (v0.2.39): Single player runs on a server thread, as vanilla does, so the world keeps ticking smoothly while the window draws. [#1514](https://github.com/horizon-rust/horizon/issues/1514) · [docs/server-levels.md](docs/server-levels.md)
+- **GPU occlusion culling on Macs** (v0.2.17): On Macs the GPU now skips terrain hidden behind hills and caves: 8 to 48% more frames per second at 32 chunks on an M4 Pro. [#1434](https://github.com/horizon-rust/horizon/issues/1434)
+- **Animated textures on the GPU** (v0.2.5): Water, lava and other animated blocks are now animated by the graphics card: 1.7 to 2.4 times better 1% lows on Intel graphics. [#1239](https://github.com/horizon-rust/horizon/issues/1239)
+- **Far Detail for integrated graphics** (v0.2.5): An optional Reduced setting for far terrain, suggested on integrated graphics, that saves 2 to 4 ms of GPU time per frame. [#1199](https://github.com/horizon-rust/horizon/issues/1199) · [#1029](https://github.com/horizon-rust/horizon/issues/1029)
+- **The launcher's mod browser** (launcher@0.2.0): Search Modrinth for mods, modpacks and resource packs from the launcher; it says before installing what works in Horizon. [#1154](https://github.com/horizon-rust/horizon/issues/1154) · [#1242](https://github.com/horizon-rust/horizon/issues/1242) · [#1243](https://github.com/horizon-rust/horizon/issues/1243) · [#1246](https://github.com/horizon-rust/horizon/issues/1246) · [docs/mod-browser.md](docs/mod-browser.md)
+- **A blocky, Minecraft-like launcher** (launcher@0.2.0): The launcher got a new blocky look in Horizon's purple, in dark and light. [#1269](https://github.com/horizon-rust/horizon/issues/1269) · [docs/design-system.md](docs/design-system.md)
+- **Dynamic lights** (v2026.10.22): An optional extra: torches you hold, drop or set on fire light up what is around them. [#1162](https://github.com/horizon-rust/horizon/issues/1162)
+- **Host a server from the launcher** (launcher-v0.15.0): The launcher's Servers page creates, starts, backs up and updates a Horizon server with buttons, and invites friends. [#1026](https://github.com/horizon-rust/horizon/issues/1026) · [docs/hosting.md](docs/hosting.md)

benchmarks/server-equal-mixed-2026-10-18/README.md

@@ -119,7 +119,7 @@ machines during the runs.
 
 ## Reproduce
 
-    curl -fsSL https://raw.githubusercontent.com/ludovic111/horizon/main/packaging/server/install.sh | sh
+    curl -fsSL https://raw.githubusercontent.com/horizon-rust/horizon/main/packaging/server/install.sh | sh
     horizon-prepare --prepare --server-jar /path/to/server.jar      # your own copy
     cargo build --release -p horizon-bots                            # on the machine that runs the bots
     # in a checkout whose .local/minecraft holds the pinned vanilla jars (tools/lab.py prepare):

benchmarks/server-four-way-2026-10-19/README.md

@@ -148,7 +148,7 @@ early, wrote no report. Its lines come from its output.
 
 ## Reproduce
 
-    curl -fsSL https://raw.githubusercontent.com/ludovic111/horizon/main/packaging/server/install.sh | sh
+    curl -fsSL https://raw.githubusercontent.com/horizon-rust/horizon/main/packaging/server/install.sh | sh
     horizon-prepare --prepare --server-jar /path/to/server.jar      # your own copy
     cargo build --release -p horizon-bots                            # on the machine that runs the bots
     # in a checkout whose .local/minecraft holds the pinned vanilla jars (tools/lab.py prepare):

benchmarks/server-mixed-2026-10-18/README.md

@@ -103,7 +103,7 @@ the Nix store, so the run set `LD_LIBRARY_PATH` to them (see #898).
 
 ## Reproduce
 
-    curl -fsSL https://raw.githubusercontent.com/ludovic111/horizon/main/packaging/server/install.sh | sh
+    curl -fsSL https://raw.githubusercontent.com/horizon-rust/horizon/main/packaging/server/install.sh | sh
     horizon-prepare --prepare --server-jar /path/to/server.jar      # your own copy
     cargo build --release -p horizon-bots                            # on the machine that runs the bots
     # in a checkout whose .local/minecraft holds the pinned vanilla jars (tools/lab.py prepare):

crates/cargo-horizon-mod/src/check.rs

@@ -97,6 +97,9 @@ impl Report {
         for r in &f.requires {
             out += &format!("  needs {} {} ({})\n", r.id, r.version, &r.sha256[..12]);
         }
+        if self.kind == Kind::NativeMod {
+            out += "  native source: unsandboxed; not executed by the registry check. Compile and test against the exact pinned Horizon and Mixins revisions before review.\n";
+        }
         if self.kind == Kind::Mod && !self.code {
             out += "  no code: content only, nothing to run\n";
         } else if self.kind == Kind::Mod {
@@ -118,6 +121,7 @@ impl Report {
 pub fn kind_of(path: &Path) -> Option<Kind> {
     match path.extension()?.to_str()? {
         "hmod" => Some(Kind::Mod),
+        "hnmod" => Some(Kind::NativeMod),
         "hpack" => Some(Kind::Modpack),
         "zip" => Some(Kind::ResourcePack),
         "hshader" => Some(Kind::Shader),
@@ -200,7 +204,7 @@ fn play(path: &Path, report: &mut Report) -> Result<(), String> {
         return Err(format!("it didn't start: {reason}"));
     }
     let client: Vec<String> = mods.commands().map(str::to_owned).collect();
-    let server: Vec<String> = mods.server_commands().map(str::to_owned).collect();
+    let server: Vec<String> = mods.server_commands().map(|c| c.name.clone()).collect();
     report.commands = [client.clone(), server.clone()].concat();
     // A server mod plays with one player on, who joins, chats and leaves.
     let steve = ServerPlayer {
@@ -273,6 +277,10 @@ fn play(path: &Path, report: &mut Report) -> Result<(), String> {
             }
             Output::OpenScreen { .. } => "opened a screen".to_string(),
             Output::CloseScreen { .. } => "closed its screen".to_string(),
+            Output::PlaceRecipe { book_id, all } => {
+                format!("placed recipe {book_id}{}", if all { " (all)" } else { "" })
+            }
+            Output::Give { item, count, .. } => format!("gave {count} {item}"),
             Output::Shake { strength, seconds } => {
                 format!("shook the camera: {strength:.2} for {seconds:.1} s")
             }

crates/cargo-horizon-mod/src/main.rs

@@ -25,7 +25,7 @@ use std::{
 };
 
 const TARGET: &str = "wasm32-unknown-unknown";
-const SDK_GIT: &str = "{ git = \"https://github.com/ludovic111/horizon\" }";
+const SDK_GIT: &str = "{ git = \"https://github.com/horizon-rust/horizon\" }";
 
 fn main() -> ExitCode {
     // Cargo runs `cargo-horizon-mod horizon-mod <args>`.

crates/cargo-horizon-mod/src/registry.rs

@@ -1,5 +1,5 @@
 //! `cargo horizon-mod registry build|review|check|list`: the registry repository's CI
-//! (`ludovic111/horizon-mods`, docs/api/mod-index.md). Network-free: the
+//! (`horizon-rust/horizon-mods`, docs/api/mod-index.md). Network-free: the
 //! workflow downloads the files and publishes what this writes.
 use horizon_mods::index::{
     FILE_HOST,
@@ -8,7 +8,7 @@ use horizon_mods::index::{
 use std::path::Path;
 
 /// Where the registry's site is published (its icons).
-const SITE: &str = "https://ludovic111.github.io/horizon-mods/";
+const SITE: &str = "https://horizon-rust.github.io/horizon-mods/";
 
 const USAGE: &str = "usage: cargo horizon-mod registry build <checkout> --files <dir> --out <index.json> [--release <url>] [--site <url>] [--generated <time>]
        cargo horizon-mod registry review <base checkout> <head checkout> --author <login> [--json]

crates/horizon-client-core/Cargo.toml

@@ -0,0 +1,14 @@
+[package]
+name = "horizon-client-core"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+rust-version = "1.90"
+description = "The client's lowest layer: chat text and translations, SNBT and NBT paths, the scoreboard, boss bars, game rules and the registry and particle tables commands name"
+
+[dependencies]
+horizon-world = { path = "../horizon-world" }
+serde_json = { version = "1.0.151", features = ["raw_value"] }
+
+[lints]
+workspace = true

crates/horizon-client-core/src/block_entity_nbt.rs

@@ -61,6 +61,16 @@ fn f32_tag(v: f32) -> Tag {
     Tag::Float(v.to_bits())
 }
 
+/// `TheEndGatewayBlockEntity.loadAdditional`: BlockPos.CODEC and Level.isInSpawnableBounds.
+pub fn gateway_exit(tag: &Tag) -> Option<[i32; 3]> {
+    let Tag::IntArray(v) = tag else { return None };
+    let p: [i32; 3] = v.as_slice().try_into().ok()?;
+    ((-30_000_000..30_000_000).contains(&p[0])
+        && (-20_000_000..20_000_000).contains(&p[1])
+        && (-30_000_000..30_000_000).contains(&p[2]))
+    .then_some(p)
+}
+
 /// What a block entity reads and writes, in `saveAdditional` order.
 struct Fields<'a> {
     input: &'a Tag,
@@ -259,7 +269,7 @@ fn is_pos(tag: &Tag) -> bool {
     matches!(tag, Tag::IntArray(v) if v.len() == 3)
 }
 /// The loaded `SignText` of one side, or the empty text.
-pub(crate) fn sign_side(tag: Option<&Tag>) -> Tag {
+pub fn sign_side(tag: Option<&Tag>) -> Tag {
     let empty = || string("");
     let mut messages: Vec<Tag> = match tag.and_then(|t| t.get("messages")) {
         Some(Tag::List(list)) => list.iter().filter_map(component).collect(),
@@ -424,10 +434,7 @@ pub fn canonical(tag: &Tag) -> Option<Tag> {
         }
         "minecraft:end_gateway" => {
             f.long("Age", 0);
-            f.keep("exit_portal", |t| {
-                is_pos(t)
-                    && matches!(t, Tag::IntArray(v) if v[1].abs() <= 30_000_000 && v[0].abs() <= 30_000_000 && v[2].abs() <= 30_000_000)
-            });
+            f.keep("exit_portal", |t| gateway_exit(t).is_some());
             if flag(tag.get("ExactTeleport")) == Some(true) {
                 f.put("ExactTeleport", boolean(true));
             }

crates/horizon-client-core/src/component.rs

@@ -1,6 +1,7 @@
 //! Text components from commands: `ComponentArgument` reads an SNBT (or JSON)
 //! value, `ComponentSerialization` turns it into styled text.
 use crate::text::{Style, Text, named_color};
+use horizon_world::nbt::Tag;
 use serde_json::{Map, Value};
 
 /// `SnbtGrammar`, enough for components: compounds, lists, quoted and
@@ -10,13 +11,18 @@ pub fn parse_snbt(input: &str) -> Result<(Value, usize), String> {
     let mut p = Parser {
         s: input.as_bytes(),
         i: 0,
+        depth: 0,
     };
     let v = p.value()?;
     Ok((v, p.i))
 }
+/// Nesting deeper than NBT's own limit (`NbtAccounter`'s 512) is refused
+/// rather than overflowing the stack.
+const SNBT_MAX_DEPTH: usize = 512;
 struct Parser<'a> {
     s: &'a [u8],
     i: usize,
+    depth: usize,
 }
 impl Parser<'_> {
     fn ws(&mut self) {
@@ -40,57 +46,22 @@ impl Parser<'_> {
         self.ws();
         match self.peek() {
             Some(b'{') => {
-                self.i += 1;
-                let mut map = Map::new();
-                self.ws();
-                if self.peek() == Some(b'}') {
-                    self.i += 1;
-                    return Ok(Value::Object(map));
-                }
-                loop {
-                    self.ws();
-                    let key = self.string()?;
-                    self.expect(b':')?;
-                    map.insert(key, self.value()?);
-                    self.ws();
-                    match self.peek() {
-                        Some(b',') => self.i += 1,
-                        Some(b'}') => {
-                            self.i += 1;
-                            return Ok(Value::Object(map));
-                        }
-                        _ => return Err("expected ',' or '}'".into()),
-                    }
+                if self.depth >= SNBT_MAX_DEPTH {
+                    return Err(format!("tag nesting too deep at {}", self.i));
                 }
+                self.depth += 1;
+                let v = self.object();
+                self.depth -= 1;
+                v
             }
             Some(b'[') => {
-                self.i += 1;
-                let mut list = Vec::new();
-                self.ws();
-                // Typed arrays [B;...], [I;...], [L;...].
-                if matches!(
-                    self.s.get(self.i..self.i + 2),
-                    Some([b'B' | b'I' | b'L', b';'])
-                ) {
-                    self.i += 2;
-                }
-                self.ws();
-                if self.peek() == Some(b']') {
-                    self.i += 1;
-                    return Ok(Value::Array(list));
-                }
-                loop {
-                    list.push(self.value()?);
-                    self.ws();
-                    match self.peek() {
-                        Some(b',') => self.i += 1,
-                        Some(b']') => {
-                            self.i += 1;
-                            return Ok(Value::Array(list));
-                        }
-                        _ => return Err("expected ',' or ']'".into()),
-                    }
+                if self.depth >= SNBT_MAX_DEPTH {
+                    return Err(format!("tag nesting too deep at {}", self.i));
                 }
+                self.depth += 1;
+                let v = self.array();
+                self.depth -= 1;
+                v
             }
             Some(b'"' | b'\'') => Ok(Value::String(self.string()?)),
             Some(_) => {
@@ -104,10 +75,20 @@ impl Parser<'_> {
                     _ => {
                         let digits = word
                             .trim_end_matches(['b', 'B', 's', 'S', 'l', 'L', 'f', 'F', 'd', 'D']);
-                        match (digits.parse::<i64>(), digits.parse::<f64>()) {
-                            (Ok(n), _) if digits.len() + 1 >= word.len() => Value::from(n),
-                            (_, Ok(f)) if digits.len() + 1 >= word.len() => Value::from(f),
-                            _ => Value::String(word),
+                        // Only digits (and an exponent) make a number: `nan`
+                        // or `Infinity`, which Rust's parse would take, stays
+                        // a string.
+                        if digits
+                            .bytes()
+                            .any(|c| c.is_ascii_alphabetic() && c != b'e' && c != b'E')
+                        {
+                            Value::String(word)
+                        } else {
+                            match (digits.parse::<i64>(), digits.parse::<f64>()) {
+                                (Ok(n), _) if digits.len() + 1 >= word.len() => Value::from(n),
+                                (_, Ok(f)) if digits.len() + 1 >= word.len() => Value::from(f),
+                                _ => Value::String(word),
+                            }
                         }
                     }
                 })
@@ -115,6 +96,59 @@ impl Parser<'_> {
             None => Err("expected a value".into()),
         }
     }
+    fn object(&mut self) -> Result<Value, String> {
+        self.i += 1;
+        let mut map = Map::new();
+        self.ws();
+        if self.peek() == Some(b'}') {
+            self.i += 1;
+            return Ok(Value::Object(map));
+        }
+        loop {
+            self.ws();
+            let key = self.string()?;
+            self.expect(b':')?;
+            map.insert(key, self.value()?);
+            self.ws();
+            match self.peek() {
+                Some(b',') => self.i += 1,
+                Some(b'}') => {
+                    self.i += 1;
+                    return Ok(Value::Object(map));
+                }
+                _ => return Err("expected ',' or '}'".into()),
+            }
+        }
+    }
+    fn array(&mut self) -> Result<Value, String> {
+        self.i += 1;
+        let mut list = Vec::new();
+        self.ws();
+        // Typed arrays [B;...], [I;...], [L;...].
+        if matches!(
+            self.s.get(self.i..self.i + 2),
+            Some([b'B' | b'I' | b'L', b';'])
+        ) {
+            self.i += 2;
+        }
+        self.ws();
+        if self.peek() == Some(b']') {
+            self.i += 1;
+            return Ok(Value::Array(list));
+        }
+        loop {
+            list.push(self.value()?);
+            self.ws();
+            match self.peek() {
+                Some(b',') => self.i += 1,
+                Some(b']') => {
+                    self.i += 1;
+                    return Ok(Value::Array(list));
+                }
+                _ => return Err("expected ',' or ']'".into()),
+            }
+        }
+    }
     fn unquoted(&mut self) -> String {
         let start = self.i;
         while let Some(c) = self.peek() {
@@ -173,20 +207,53 @@ fn object_style(o: &serde_json::Map<String, Value>) -> Style {
     if let Some(e) = o.get("click_event").and_then(Value::as_object) {
         let text = |k: &str| e.get(k).and_then(Value::as_str).map(str::to_owned);
         style.click = match e.get("action").and_then(Value::as_str) {
+            // ClickEvent.OpenUrl.CODEC: ExtraCodecs.UNTRUSTED_URI allows http and
+            // https only, the scheme in any case (Util.parseAndValidateUntrustedUri).
+            Some("open_url") => text("url")
+                .filter(|u| {
+                    u.split_once(':').is_some_and(|(scheme, _)| {
+                        scheme.eq_ignore_ascii_case("http") || scheme.eq_ignore_ascii_case("https")
+                    })
+                })
+                .map(crate::text::ClickEvent::OpenUrl),
+            // ClickEvent.ChangePage.CODEC: ExtraCodecs.POSITIVE_INT.
+            Some("change_page") => e
+                .get("page")
+                .and_then(Value::as_i64)
+                .and_then(|p| i32::try_from(p).ok())
+                .filter(|p| *p >= 1)
+                .map(crate::text::ClickEvent::ChangePage),
             Some("suggest_command") => text("command").map(crate::text::ClickEvent::SuggestCommand),
+            Some("run_command") => text("command").map(crate::text::ClickEvent::RunCommand),
             Some("copy_to_clipboard") => {
                 text("value").map(crate::text::ClickEvent::CopyToClipboard)
             }
+            // ClickEvent.ShowDialog.CODEC: a `minecraft:dialog` registry id or
+            // the dialog itself; the server may send it (isAllowedFromServer).
+            Some("show_dialog") => e.get("dialog").map(|dialog| {
+                crate::text::ClickEvent::ShowDialog(crate::scoreboard::json_to_tag(dialog))
+            }),
             _ => None,
         };
     }
-    // HoverEvent.ShowText.
-    if let Some(e) = o.get("hover_event").and_then(Value::as_object)
-        && e.get("action").and_then(Value::as_str) == Some("show_text")
-        && let Some(value) = e.get("value")
-    {
-        style.hover = Some(Box::new(to_text(value, &mut |s| Text::literal(s))));
+    // HoverEvent.ShowText and ShowItem.
+    if let Some(e) = o.get("hover_event").and_then(Value::as_object) {
+        match e.get("action").and_then(Value::as_str) {
+            Some("show_text") => {
+                if let Some(value) = e.get("value") {
+                    style.hover = Some(Box::new(to_text(value, &mut |s| Text::literal(s))));
+                }
+            }
+            Some("show_item") if e.get("id").is_some_and(Value::is_string) => {
+                style.hover_item = Some(Box::new(Value::Object(e.clone())));
+            }
+            _ => {}
+        }
     }
+    style.insertion = o
+        .get("insertion")
+        .and_then(Value::as_str)
+        .map(str::to_owned);
     style
 }
 /// `ComponentSerialization.CODEC` decoding into text. `selector` components
@@ -252,7 +319,7 @@ pub fn to_text_with(
             } else if let Some(sel) = o.get("selector").and_then(Value::as_str) {
                 resolve(sel)
             } else if let Some(key) = o.get("keybind").and_then(Value::as_str) {
-                crate::keybinds::display_name(key)
+                crate::key_display::display_name(key)
             } else {
                 Text::empty()
             };
@@ -271,6 +338,15 @@ pub fn to_text_with(
     }
 }
 
+/// `CustomName` as text: a string keeps its legacy formatting codes, anything
+/// else is a component (`ComponentSerialization`).
+pub fn name_text(tag: &Tag) -> Text {
+    match tag {
+        Tag::String(s) => Text::legacy(&s.to_string_lossy()),
+        t => crate::scoreboard::comp_text(&crate::scoreboard::tag_to_json(t)),
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -308,4 +384,22 @@ mod tests {
         let t = to_text(&v, &mut |_| Text::empty());
         assert_eq!(t.spans[0].style.font, None);
     }
+
+    #[test]
+    fn snbt_nesting_is_bounded() {
+        let nest = |n: usize| format!("{}1{}", "[".repeat(n), "]".repeat(n));
+        assert!(parse_snbt(&nest(512)).is_ok());
+        assert!(parse_snbt(&nest(513)).is_err());
+        assert!(parse_snbt(&nest(100_000)).is_err());
+    }
+
+    #[test]
+    fn bare_words_that_look_numeric_stay_strings() {
+        let (v, _) = parse_snbt("{text:nan}").unwrap();
+        assert_eq!(v["text"], Value::String("nan".into()));
+        let (v, _) = parse_snbt("{text:Infinity}").unwrap();
+        assert_eq!(v["text"], Value::String("Infinity".into()));
+        let (v, _) = parse_snbt("{n:1.5}").unwrap();
+        assert_eq!(v["n"], Value::from(1.5));
+    }
 }

crates/horizon-client-core/src/gamerules.rs

@@ -292,27 +292,4 @@ mod tests {
         assert_eq!(GameRules::load(&dir), rules);
         let _ = fs::remove_dir_all(dir);
     }
-    /// The world's save (Level.write) writes the rules as they are now, and a
-    /// world opened again reads them back (#74).
-    #[test]
-    fn level_save_keeps_changed_rules() {
-        let dir =
-            std::env::temp_dir().join(format!("horizon-gamerules-level-{}", std::process::id()));
-        let _ = fs::remove_dir_all(&dir);
-        let mut level = crate::save::Level::default();
-        level.write(&dir).unwrap();
-        // Rules changed while playing, then saved and loaded again.
-        let mut rules = GameRules::load(&dir);
-        assert_eq!(rules, GameRules::default());
-        assert!(rules.set("advance_time", Value::Bool(false)));
-        assert!(rules.set("advance_weather", Value::Bool(false)));
-        assert!(rules.set("random_tick_speed", Value::Int(0)));
-        level.game_rules = rules.by_name();
-        level.write(&dir).unwrap();
-        assert_eq!(GameRules::load(&dir), rules);
-        let read = crate::save::Level::read(&dir).unwrap();
-        assert_eq!(read.game_rules, rules.by_name());
-        assert_eq!(read.game_rule("advance_time"), 0);
-        let _ = fs::remove_dir_all(dir);
-    }
 }

crates/horizon-client-core/src/identifier.rs

@@ -0,0 +1,35 @@
+//! Resource identifiers (`Identifier`).
+
+/// Identifier.parse: `ns:path` or `path`, validated.
+pub fn parse_identifier(raw: &str) -> Option<String> {
+    let (ns, path) = match raw.split_once(':') {
+        Some(("", path)) => ("minecraft", path),
+        Some((ns, path)) => (ns, path),
+        None => ("minecraft", raw),
+    };
+    let ns_ok = ns != ".."
+        && ns
+            .chars()
+            .all(|c| c.is_ascii_lowercase() || c.is_ascii_digit() || matches!(c, '_' | '.' | '-'));
+    let path_ok = path.chars().all(|c| {
+        c.is_ascii_lowercase() || c.is_ascii_digit() || matches!(c, '_' | '.' | '-' | '/')
+    });
+    (ns_ok && path_ok).then(|| format!("{ns}:{path}"))
+}
+
+/// `Identifier.CODEC` parsing an entity id: lowercase namespace and path
+/// characters, `minecraft` when the namespace is left out.
+pub fn normalize_id(s: &str) -> Option<String> {
+    let (ns, path) = match s.split_once(':') {
+        Some((ns, path)) => (if ns.is_empty() { "minecraft" } else { ns }, path),
+        None => ("minecraft", s),
+    };
+    let ok = |c: char, slash: bool| {
+        c.is_ascii_lowercase()
+            || c.is_ascii_digit()
+            || matches!(c, '_' | '-' | '.')
+            || slash && c == '/'
+    };
+    (ns.chars().all(|c| ok(c, false)) && path.chars().all(|c| ok(c, true)))
+        .then(|| format!("{ns}:{path}"))
+}

crates/horizon-client-core/src/key_display.rs

@@ -0,0 +1,38 @@
+//! Key display names (`InputConstants.Key.getDisplayName`), shared by key
+//! mappings and `keybind` text components.
+use crate::text::Text;
+
+/// InputConstants.Key.getDisplayName: one-character keys as the upper-case
+/// character, others by translation.
+pub fn display_name(key: &str) -> Text {
+    if let Some(rest) = key.strip_prefix("key.keyboard.")
+        && rest.chars().count() == 1
+    {
+        let c = rest.to_uppercase();
+        return Text::literal(c);
+    }
+    let symbol = match key {
+        "key.keyboard.minus" => Some("-"),
+        "key.keyboard.equal" => Some("="),
+        "key.keyboard.left.bracket" => Some("["),
+        "key.keyboard.right.bracket" => Some("]"),
+        "key.keyboard.backslash" => Some("\\"),
+        "key.keyboard.semicolon" => Some(";"),
+        "key.keyboard.apostrophe" => Some("'"),
+        "key.keyboard.grave.accent" => Some("`"),
+        "key.keyboard.comma" => Some(","),
+        "key.keyboard.period" => Some("."),
+        "key.keyboard.slash" => Some("/"),
+        _ => None,
+    };
+    if let Some(s) = symbol {
+        return Text::literal(s);
+    }
+    if let Some(n) = key.strip_prefix("key.mouse.")
+        && n.parse::<u32>().is_ok()
+        && !crate::lang::has(key)
+    {
+        return Text::translate("key.mouse", &[Text::literal(n)]);
+    }
+    Text::translate(key, &[])
+}

crates/horizon-client-core/src/lang.rs

@@ -4,7 +4,10 @@
 //! language used by every screen.
 use std::{
     collections::{BTreeMap, HashMap},
-    sync::{Arc, RwLock},
+    sync::{
+        Arc, RwLock,
+        atomic::{AtomicBool, Ordering},
+    },
 };
 
 #[derive(Clone, Debug, PartialEq, Eq)]
@@ -23,15 +26,24 @@ impl LanguageInfo {
 #[derive(Default)]
 pub struct Language {
     pub code: String,
+    /// `LanguageInfo.bidirectional`: text without a strong character reads
+    /// right to left (`ClientLanguage.defaultRightToLeft`).
+    bidirectional: bool,
     map: HashMap<String, String>,
 }
 pub const DEFAULT: &str = "en_us";
 
 static CURRENT: RwLock<Option<Arc<Language>>> = RwLock::new(None);
+/// The current language's `bidirectional`, read for every drawn string.
+static BIDIRECTIONAL: AtomicBool = AtomicBool::new(false);
 
 /// A source of resource files: the prepared root plus packs, highest priority last.
 pub trait ResourceSource {
     fn read(&self, path: &str) -> Option<Vec<u8>>;
+    /// Whether `path` is there, without reading it where the source can tell.
+    fn exists(&self, path: &str) -> bool {
+        self.read(path).is_some()
+    }
     /// The namespaces under `assets/` (resource packs may add their own).
     fn namespaces(&self) -> Vec<String> {
         vec!["minecraft".into()]
@@ -42,8 +54,12 @@ struct Bundled;
 impl ResourceSource for Bundled {
     fn read(&self, path: &str) -> Option<Vec<u8>> {
         let body = match path {
-            "assets/horizon/lang/en_us.json" => include_str!("../assets/horizon/lang/en_us.json"),
-            "assets/horizon/lang/ru_ru.json" => include_str!("../assets/horizon/lang/ru_ru.json"),
+            "assets/horizon/lang/en_us.json" => {
+                include_str!("../../horizon-client/assets/horizon/lang/en_us.json")
+            }
+            "assets/horizon/lang/ru_ru.json" => {
+                include_str!("../../horizon-client/assets/horizon/lang/ru_ru.json")
+            }
             _ => return None,
         };
         Some(body.as_bytes().to_vec())
@@ -56,6 +72,9 @@ impl ResourceSource for std::path::PathBuf {
     fn read(&self, path: &str) -> Option<Vec<u8>> {
         std::fs::read(self.join(path)).ok()
     }
+    fn exists(&self, path: &str) -> bool {
+        self.join(path).is_file()
+    }
     fn namespaces(&self) -> Vec<String> {
         std::fs::read_dir(self.join("assets"))
             .into_iter()
@@ -130,8 +149,12 @@ impl Language {
         {
             apply_deprecated(&mut map, &bytes);
         }
+        let bidirectional = available(sources)
+            .iter()
+            .any(|info| info.code == code && info.bidirectional);
         Self {
             code: code.to_owned(),
+            bidirectional,
             map,
         }
     }
@@ -174,7 +197,7 @@ pub fn available(sources: &[&dyn ResourceSource]) -> Vec<LanguageInfo> {
             for (code, info) in value["language"].as_object().into_iter().flatten() {
                 // Only languages whose file exists somewhere are selectable.
                 let file = format!("assets/minecraft/lang/{code}.json");
-                if code != DEFAULT && !sources.iter().any(|s| s.read(&file).is_some()) {
+                if code != DEFAULT && !sources.iter().any(|s| s.exists(&file)) {
                     continue;
                 }
                 found.insert(
@@ -193,11 +216,16 @@ pub fn available(sources: &[&dyn ResourceSource]) -> Vec<LanguageInfo> {
 }
 
 pub fn set(language: Language) {
+    BIDIRECTIONAL.store(language.bidirectional, Ordering::Relaxed);
     *CURRENT.write().unwrap_or_else(|e| e.into_inner()) = Some(Arc::new(language));
 }
 pub fn current() -> Option<Arc<Language>> {
     CURRENT.read().unwrap_or_else(|e| e.into_inner()).clone()
 }
+/// `ClientLanguage.defaultRightToLeft` of the current language.
+pub fn bidirectional() -> bool {
+    BIDIRECTIONAL.load(Ordering::Relaxed)
+}
 pub fn code() -> String {
     current().map_or_else(|| DEFAULT.to_owned(), |l| l.code.clone())
 }
@@ -263,4 +291,26 @@ mod tests {
         );
         assert_eq!(langs[1].label(), "Français (France)");
     }
+
+    #[test]
+    fn languages_are_listed_without_reading_their_files() {
+        struct NoLangReads;
+        impl ResourceSource for NoLangReads {
+            fn read(&self, path: &str) -> Option<Vec<u8>> {
+                assert!(!path.contains("/lang/"), "read {path}");
+                (path == "assets/pack.mcmeta").then(|| {
+                    br#"{"language":{"fr_fr":{"name":"French"},"de_de":{"name":"German"}}}"#
+                        .to_vec()
+                })
+            }
+            fn exists(&self, path: &str) -> bool {
+                path == "assets/minecraft/lang/fr_fr.json"
+            }
+        }
+        let langs = available(&[&NoLangReads]);
+        assert_eq!(
+            langs.iter().map(|l| l.code.as_str()).collect::<Vec<_>>(),
+            ["en_us", "fr_fr"]
+        );
+    }
 }

crates/horizon-client-core/src/lib.rs

@@ -0,0 +1,28 @@
+//! The client's lowest layer, below commands and gameplay: chat text and
+//! translations, SNBT and NBT paths, text components, the scoreboard, boss
+//! bars, game rules, block entity NBT tables, and the registry, particle and
+//! sound source tables commands name, and the `pack.mcmeta` filter regex.
+//! horizon-client re-exports each module under its old path
+//! (`horizon_client::text`, ...).
+#![forbid(unsafe_code)]
+pub mod block_entity_nbt;
+pub mod bossbar;
+pub mod component;
+pub mod fastutil_order;
+pub mod gamerules;
+pub mod identifier;
+pub mod key_display;
+pub mod lang;
+pub mod nbt_path;
+pub mod nbt_value;
+pub mod particle_type;
+pub mod pattern;
+pub mod potions;
+pub mod registries;
+pub mod scoreboard;
+pub mod snbt;
+pub mod sound_source;
+pub mod text;
+pub mod uuid;
+pub mod who;
+pub type Result<T> = std::result::Result<T, Box<dyn std::error::Error>>;

crates/horizon-client-core/src/nbt_value.rs

@@ -0,0 +1,32 @@
+//! Reading and writing single NBT values the way vanilla's codecs accept them.
+use horizon_world::nbt::Tag;
+
+pub fn string(s: &str) -> Tag {
+    Tag::String(s.into())
+}
+pub fn text(tag: Option<&Tag>) -> Option<String> {
+    match tag {
+        Some(Tag::String(s)) => Some(s.to_string_lossy()),
+        _ => None,
+    }
+}
+/// Any numeric tag as i64 (vanilla's `getIntOr` etc. accept every number type).
+pub fn number(tag: Option<&Tag>) -> Option<i64> {
+    Some(match tag? {
+        Tag::Byte(v) => i64::from(*v),
+        Tag::Short(v) => i64::from(*v),
+        Tag::Int(v) => i64::from(*v),
+        Tag::Long(v) => *v,
+        Tag::Float(b) => f32::from_bits(*b) as i64,
+        Tag::Double(b) => f64::from_bits(*b) as i64,
+        _ => return None,
+    })
+}
+/// Any numeric tag as f64, keeping a float's or double's fraction.
+pub fn float(tag: Option<&Tag>) -> Option<f64> {
+    Some(match tag? {
+        Tag::Float(b) => f64::from(f32::from_bits(*b)),
+        Tag::Double(b) => f64::from_bits(*b),
+        other => number(Some(other))? as f64,
+    })
+}

crates/horizon-client-core/src/particle_type.rs

@@ -0,0 +1,209 @@
+//! Particle types (`ParticleTypes`): the vanilla particle types with a client
+//! implementation, by registry name, and their per-type flags.
+
+macro_rules! particle_types {
+    ($($variant:ident = $name:literal),* $(,)?) => {
+        /// Vanilla particle types with a client implementation here.
+        #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+        pub enum ParticleType { $($variant),* }
+        impl ParticleType {
+            pub const ALL: &'static [ParticleType] = &[$(ParticleType::$variant),*];
+            /// Registry path (`minecraft:<name>`), also the sprite-set file name.
+            pub fn name(self) -> &'static str {
+                match self { $(ParticleType::$variant => $name),* }
+            }
+            pub fn from_name(name: &str) -> Option<Self> {
+                let name = name.strip_prefix("minecraft:").unwrap_or(name);
+                match name { $($name => Some(ParticleType::$variant),)* _ => None }
+            }
+        }
+    };
+}
+particle_types! {
+    Block = "block",
+    BlockCrumble = "block_crumble",
+    Trail = "trail",
+    DustPillar = "dust_pillar",
+    FallingDust = "falling_dust",
+    Smoke = "smoke",
+    LargeSmoke = "large_smoke",
+    WhiteSmoke = "white_smoke",
+    Flame = "flame",
+    SoulFireFlame = "soul_fire_flame",
+    CopperFireFlame = "copper_fire_flame",
+    SmallFlame = "small_flame",
+    Lava = "lava",
+    DrippingWater = "dripping_water",
+    FallingWater = "falling_water",
+    DrippingLava = "dripping_lava",
+    FallingLava = "falling_lava",
+    LandingLava = "landing_lava",
+    DrippingHoney = "dripping_honey",
+    FallingHoney = "falling_honey",
+    LandingHoney = "landing_honey",
+    FallingNectar = "falling_nectar",
+    FallingSporeBlossom = "falling_spore_blossom",
+    SporeBlossomAir = "spore_blossom_air",
+    DrippingObsidianTear = "dripping_obsidian_tear",
+    FallingObsidianTear = "falling_obsidian_tear",
+    LandingObsidianTear = "landing_obsidian_tear",
+    DrippingDripstoneWater = "dripping_dripstone_water",
+    FallingDripstoneWater = "falling_dripstone_water",
+    DrippingDripstoneLava = "dripping_dripstone_lava",
+    FallingDripstoneLava = "falling_dripstone_lava",
+    Splash = "splash",
+    Rain = "rain",
+    Bubble = "bubble",
+    SulfurBubbles = "sulfur_bubbles",
+    BubblePop = "bubble_pop",
+    BubbleColumnUp = "bubble_column_up",
+    CurrentDown = "current_down",
+    Underwater = "underwater",
+    Portal = "portal",
+    ReversePortal = "reverse_portal",
+    Enchant = "enchant",
+    Nautilus = "nautilus",
+    VaultConnection = "vault_connection",
+    Crit = "crit",
+    EnchantedHit = "enchanted_hit",
+    DamageIndicator = "damage_indicator",
+    Heart = "heart",
+    AngryVillager = "angry_villager",
+    HappyVillager = "happy_villager",
+    Composter = "composter",
+    Mycelium = "mycelium",
+    Dolphin = "dolphin",
+    EggCrack = "egg_crack",
+    Poof = "poof",
+    Explosion = "explosion",
+    ExplosionEmitter = "explosion_emitter",
+    CampfireCosySmoke = "campfire_cosy_smoke",
+    CampfireSignalSmoke = "campfire_signal_smoke",
+    Note = "note",
+    Dust = "dust",
+    TotemOfUndying = "totem_of_undying",
+    Firework = "firework",
+    EndRod = "end_rod",
+    Ash = "ash",
+    WhiteAsh = "white_ash",
+    CrimsonSpore = "crimson_spore",
+    WarpedSpore = "warped_spore",
+    CherryLeaves = "cherry_leaves",
+    PaleOakLeaves = "pale_oak_leaves",
+    TintedLeaves = "tinted_leaves",
+    Effect = "effect",
+    InstantEffect = "instant_effect",
+    EntityEffect = "entity_effect",
+    Witch = "witch",
+    Infested = "infested",
+    Cloud = "cloud",
+    Sneeze = "sneeze",
+    Snowflake = "snowflake",
+    Soul = "soul",
+    SculkSoul = "sculk_soul",
+    DragonBreath = "dragon_breath",
+    Gust = "gust",
+    SmallGust = "small_gust",
+    GustEmitterLarge = "gust_emitter_large",
+    GustEmitterSmall = "gust_emitter_small",
+    DustColorTransition = "dust_color_transition",
+    SculkCharge = "sculk_charge",
+    SculkChargePop = "sculk_charge_pop",
+    Shriek = "shriek",
+    SonicBoom = "sonic_boom",
+    Vibration = "vibration",
+    SweepAttack = "sweep_attack",
+    Glow = "glow",
+    WaxOn = "wax_on",
+    WaxOff = "wax_off",
+    ElectricSpark = "electric_spark",
+    Scrape = "scrape",
+    SquidInk = "squid_ink",
+    GlowSquidInk = "glow_squid_ink",
+    Item = "item",
+    ItemSlime = "item_slime",
+    ItemSnowball = "item_snowball",
+    ItemCobweb = "item_cobweb",
+    SulfurCubeGoo = "sulfur_cube_goo",
+    Flash = "flash",
+    Firefly = "firefly",
+    TrialSpawnerDetection = "trial_spawner_detection",
+    TrialSpawnerDetectionOminous = "trial_spawner_detection_ominous",
+    TrialOmen = "trial_omen",
+    RaidOmen = "raid_omen",
+    OminousSpawning = "ominous_spawning",
+    Spit = "spit",
+    Fishing = "fishing",
+    DustPlume = "dust_plume",
+    RedPoplarLeaves = "red_poplar_leaves",
+    OrangePoplarLeaves = "orange_poplar_leaves",
+    YellowPoplarLeaves = "yellow_poplar_leaves",
+    PauseMobGrowth = "pause_mob_growth",
+    ResetMobGrowth = "reset_mob_growth",
+    BlockMarker = "block_marker",
+}
+impl ParticleType {
+    /// `ParticleType.getOverrideLimiter` (`ParticleTypes.register(name, true)`):
+    /// spawned regardless of distance.
+    pub fn override_limiter(self) -> bool {
+        matches!(
+            self,
+            Self::BlockMarker
+                | Self::DamageIndicator
+                | Self::ExplosionEmitter
+                | Self::Explosion
+                | Self::Gust
+                | Self::GustEmitterLarge
+                | Self::GustEmitterSmall
+                | Self::SonicBoom
+                | Self::SculkCharge
+                | Self::SculkChargePop
+                | Self::Vibration
+                | Self::Poof
+                | Self::Spit
+                | Self::SquidInk
+                | Self::SweepAttack
+                | Self::CampfireCosySmoke
+                | Self::CampfireSignalSmoke
+                | Self::GlowSquidInk
+                | Self::Glow
+                | Self::WaxOn
+                | Self::WaxOff
+                | Self::ElectricSpark
+                | Self::Scrape
+                | Self::TrialSpawnerDetection
+                | Self::TrialSpawnerDetectionOminous
+                | Self::VaultConnection
+                | Self::OminousSpawning
+        )
+    }
+    /// `SingleQuadParticle.Layer.translucent`: types whose vanilla particle class
+    /// hardcodes the translucent layer, drawn after translucent terrain.
+    /// `TerrainParticle`, `BreakingItemParticle` and `BlockMarker` resolve their
+    /// layer from the sprite instead (`Layer.bySprite`); see the `translucent`
+    /// sprite set on the engine.
+    pub fn translucent_layer(self) -> bool {
+        match self {
+            // CampfireSmokeParticle.
+            Self::CampfireCosySmoke | Self::CampfireSignalSmoke
+            // PlayerCloudParticle.
+            | Self::Cloud | Self::Sneeze
+            // SpellParticle.
+            | Self::Effect | Self::InstantEffect | Self::EntityEffect
+            | Self::Witch | Self::Infested | Self::TrialOmen | Self::RaidOmen
+            // EmissiveRisingParticle.
+            | Self::Soul | Self::SculkSoul
+            // SculkChargeParticle, SculkChargePopParticle, ShriekParticle,
+            // VibrationSignalParticle, FireflyParticle, OverlayParticle.
+            | Self::SculkCharge | Self::SculkChargePop | Self::Shriek
+            | Self::Vibration | Self::Firefly | Self::Flash
+            // SimpleAnimatedParticle and its subclasses: EndRodParticle,
+            // SparkParticle (firework), SquidInkParticle, TotemParticle.
+            | Self::EndRod | Self::Firework | Self::SquidInk | Self::GlowSquidInk
+            | Self::TotemOfUndying
+            // FlyTowardsPositionParticle: its LifetimeAlpha(0, 0.6, 0.25, 1) is not opaque.
+            | Self::VaultConnection => true,
+            _ => false,
+        }
+    }
+}

crates/horizon-client-core/src/potions.rs

@@ -0,0 +1,249 @@
+//! The `MobEffects` and `Potions` registries (code in vanilla, ported as
+//! tables): each effect's colour and category, each potion's effects, and the
+//! potion colour mix. horizon-client re-exports them from `brewing`.
+use std::{collections::HashMap, sync::OnceLock};
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Category {
+    Beneficial,
+    Harmful,
+    Neutral,
+}
+/// A `MobEffect`: id (without namespace), colour, category, instantaneous.
+#[derive(Clone, Copy, Debug)]
+pub struct EffectDef {
+    pub id: &'static str,
+    pub color: u32,
+    pub category: Category,
+    pub instant: bool,
+}
+const fn fx(id: &'static str, color: u32, category: Category) -> EffectDef {
+    EffectDef {
+        id,
+        color,
+        category,
+        instant: false,
+    }
+}
+use Category::{Beneficial as B, Harmful as H, Neutral as N};
+/// `MobEffects` in registration order.
+pub const EFFECTS: &[EffectDef] = &[
+    fx("speed", 3402751, B),
+    fx("slowness", 9154528, H),
+    fx("haste", 14270531, B),
+    fx("mining_fatigue", 4866583, H),
+    fx("strength", 16762624, B),
+    EffectDef {
+        id: "instant_health",
+        color: 16262179,
+        category: B,
+        instant: true,
+    },
+    EffectDef {
+        id: "instant_damage",
+        color: 11101546,
+        category: H,
+        instant: true,
+    },
+    fx("jump_boost", 16646020, B),
+    fx("nausea", 5578058, H),
+    fx("regeneration", 13458603, B),
+    fx("resistance", 9520880, B),
+    fx("fire_resistance", 16750848, B),
+    fx("water_breathing", 10017472, B),
+    fx("invisibility", 16185078, B),
+    fx("blindness", 2039587, H),
+    fx("night_vision", 12779366, B),
+    fx("hunger", 5797459, H),
+    fx("weakness", 4738376, H),
+    fx("poison", 8889187, H),
+    fx("wither", 7561558, H),
+    fx("health_boost", 16284963, B),
+    fx("absorption", 2445989, B),
+    EffectDef {
+        id: "saturation",
+        color: 16262179,
+        category: B,
+        instant: true,
+    },
+    fx("glowing", 9740385, N),
+    fx("levitation", 13565951, H),
+    fx("luck", 5882118, B),
+    fx("unluck", 12624973, H),
+    fx("slow_falling", 15978425, B),
+    fx("conduit_power", 1950417, B),
+    fx("dolphins_grace", 8954814, B),
+    fx("bad_omen", 745784, N),
+    fx("hero_of_the_village", 4521796, B),
+    fx("darkness", 2696993, H),
+    fx("trial_omen", 1484454, N),
+    fx("raid_omen", 14565464, N),
+    fx("wind_charged", 12438015, H),
+    fx("weaving", 7891290, H),
+    fx("oozing", 10092451, H),
+    fx("infested", 9214860, H),
+    fx("breath_of_the_nautilus", 65518, B),
+];
+pub fn effect(id: &str) -> Option<&'static EffectDef> {
+    let id = id.trim_start_matches("minecraft:");
+    EFFECTS.iter().find(|e| e.id == id)
+}
+/// Namespaced effect ids for mob effect storage.
+pub fn namespaced(id: &'static str) -> &'static str {
+    static IDS: OnceLock<HashMap<&'static str, &'static str>> = OnceLock::new();
+    IDS.get_or_init(|| {
+        EFFECTS
+            .iter()
+            .map(|e| {
+                (
+                    e.id,
+                    &*Box::leak(format!("minecraft:{}", e.id).into_boxed_str()),
+                )
+            })
+            .collect()
+    })
+    .get(id)
+    .copied()
+    .unwrap_or(id)
+}
+/// A `Potion`: id, name suffix (`item.minecraft.potion.effect.<name>`) and
+/// effects as (effect, duration ticks, amplifier).
+#[derive(Clone, Copy, Debug)]
+pub struct PotionDef {
+    pub id: &'static str,
+    pub name: &'static str,
+    pub effects: &'static [(&'static str, i32, i32)],
+}
+const fn p(
+    id: &'static str,
+    name: &'static str,
+    effects: &'static [(&'static str, i32, i32)],
+) -> PotionDef {
+    PotionDef { id, name, effects }
+}
+/// `Potions` in registration order.
+pub const POTIONS: &[PotionDef] = &[
+    p("water", "water", &[]),
+    p("mundane", "mundane", &[]),
+    p("thick", "thick", &[]),
+    p("awkward", "awkward", &[]),
+    p("night_vision", "night_vision", &[("night_vision", 3600, 0)]),
+    p(
+        "long_night_vision",
+        "night_vision",
+        &[("night_vision", 9600, 0)],
+    ),
+    p("invisibility", "invisibility", &[("invisibility", 3600, 0)]),
+    p(
+        "long_invisibility",
+        "invisibility",
+        &[("invisibility", 9600, 0)],
+    ),
+    p("leaping", "leaping", &[("jump_boost", 3600, 0)]),
+    p("long_leaping", "leaping", &[("jump_boost", 9600, 0)]),
+    p("strong_leaping", "leaping", &[("jump_boost", 1800, 1)]),
+    p(
+        "fire_resistance",
+        "fire_resistance",
+        &[("fire_resistance", 3600, 0)],
+    ),
+    p(
+        "long_fire_resistance",
+        "fire_resistance",
+        &[("fire_resistance", 9600, 0)],
+    ),
+    p("swiftness", "swiftness", &[("speed", 3600, 0)]),
+    p("long_swiftness", "swiftness", &[("speed", 9600, 0)]),
+    p("strong_swiftness", "swiftness", &[("speed", 1800, 1)]),
+    p("slowness", "slowness", &[("slowness", 1800, 0)]),
+    p("long_slowness", "slowness", &[("slowness", 4800, 0)]),
+    p("strong_slowness", "slowness", &[("slowness", 400, 3)]),
+    p(
+        "turtle_master",
+        "turtle_master",
+        &[("slowness", 400, 3), ("resistance", 400, 2)],
+    ),
+    p(
+        "long_turtle_master",
+        "turtle_master",
+        &[("slowness", 800, 3), ("resistance", 800, 2)],
+    ),
+    p(
+        "strong_turtle_master",
+        "turtle_master",
+        &[("slowness", 400, 5), ("resistance", 400, 3)],
+    ),
+    p(
+        "water_breathing",
+        "water_breathing",
+        &[("water_breathing", 3600, 0)],
+    ),
+    p(
+        "long_water_breathing",
+        "water_breathing",
+        &[("water_breathing", 9600, 0)],
+    ),
+    p("healing", "healing", &[("instant_health", 1, 0)]),
+    p("strong_healing", "healing", &[("instant_health", 1, 1)]),
+    p("harming", "harming", &[("instant_damage", 1, 0)]),
+    p("strong_harming", "harming", &[("instant_damage", 1, 1)]),
+    p("poison", "poison", &[("poison", 900, 0)]),
+    p("long_poison", "poison", &[("poison", 1800, 0)]),
+    p("strong_poison", "poison", &[("poison", 432, 1)]),
+    p("regeneration", "regeneration", &[("regeneration", 900, 0)]),
+    p(
+        "long_regeneration",
+        "regeneration",
+        &[("regeneration", 1800, 0)],
+    ),
+    p(
+        "strong_regeneration",
+        "regeneration",
+        &[("regeneration", 450, 1)],
+    ),
+    p("strength", "strength", &[("strength", 3600, 0)]),
+    p("long_strength", "strength", &[("strength", 9600, 0)]),
+    p("strong_strength", "strength", &[("strength", 1800, 1)]),
+    p("weakness", "weakness", &[("weakness", 1800, 0)]),
+    p("long_weakness", "weakness", &[("weakness", 4800, 0)]),
+    p("luck", "luck", &[("luck", 6000, 0)]),
+    p("slow_falling", "slow_falling", &[("slow_falling", 1800, 0)]),
+    p(
+        "long_slow_falling",
+        "slow_falling",
+        &[("slow_falling", 4800, 0)],
+    ),
+    p("wind_charged", "wind_charged", &[("wind_charged", 3600, 0)]),
+    p("weaving", "weaving", &[("weaving", 3600, 0)]),
+    p("oozing", "oozing", &[("oozing", 3600, 0)]),
+    p("infested", "infested", &[("infested", 3600, 0)]),
+];
+pub fn potion(id: &str) -> Option<&'static PotionDef> {
+    let id = id.trim_start_matches("minecraft:");
+    POTIONS.iter().find(|p| p.id == id)
+}
+/// `PotionContents.BASE_POTION_COLOR` (ARGB -13083194) as RGB.
+pub const BASE_POTION_COLOR: u32 = 0x385DC6;
+/// `PotionContents.getColor`: amplifier-weighted mix of visible effect colours.
+pub fn potion_color(id: Option<&str>) -> u32 {
+    let Some(def) = id.and_then(potion) else {
+        return BASE_POTION_COLOR;
+    };
+    let (mut r, mut g, mut b, mut total) = (0u32, 0u32, 0u32, 0u32);
+    for (e, _, amp) in def.effects {
+        let Some(e) = effect(e) else { continue };
+        let w = *amp as u32 + 1;
+        r += w * (e.color >> 16 & 255);
+        g += w * (e.color >> 8 & 255);
+        b += w * (e.color & 255);
+        total += w;
+    }
+    match (
+        r.checked_div(total),
+        g.checked_div(total),
+        b.checked_div(total),
+    ) {
+        (Some(r), Some(g), Some(b)) => (r << 16) | (g << 8) | b,
+        _ => BASE_POTION_COLOR,
+    }
+}

crates/horizon-client-core/src/registries.rs

@@ -0,0 +1,191 @@
+//! Registry contents and source state that commands validate and complete
+//! arguments against (what the server's registry access holds).
+use std::collections::BTreeMap;
+
+/// Registry contents and source state used to validate and complete arguments.
+#[derive(Clone, Debug, Default)]
+pub struct Registries {
+    /// Permission level of the command source.
+    pub permission: u8,
+    pub items: Vec<String>,
+    pub item_tags: Vec<String>,
+    /// Block id -> (property, allowed values).
+    pub blocks: BTreeMap<String, Vec<(String, Vec<String>)>>,
+    pub block_tags: Vec<String>,
+    /// Entity types that `summon` can create.
+    pub summonable: Vec<String>,
+    /// Every entity type (selector `type=`).
+    pub entity_types: Vec<String>,
+    pub effects: Vec<String>,
+    pub enchantments: Vec<String>,
+    pub structures: Vec<String>,
+    pub biomes: Vec<String>,
+    pub dimensions: Vec<String>,
+    pub clocks: Vec<String>,
+    pub timelines: Vec<String>,
+    pub time_markers: Vec<String>,
+    pub advancements: Vec<String>,
+    /// Game rule name -> integer-valued.
+    pub game_rules: Vec<(String, bool)>,
+    pub players: Vec<String>,
+    /// Scoreboard objective names, team names and tracked score holders.
+    pub objectives: Vec<String>,
+    pub teams: Vec<String>,
+    pub tracked: Vec<String>,
+    /// Loaded datapack functions (`ns:path`) and function tags (`ns:path`).
+    pub functions: Vec<String>,
+    /// `/data ... storage` ids.
+    pub storages: Vec<String>,
+    /// Boss bar ids and datapack predicate ids.
+    pub bossbars: Vec<String>,
+    pub predicates: Vec<String>,
+    pub item_modifiers: Vec<String>,
+    pub schedules: Vec<String>,
+    pub stopwatches: Vec<String>,
+    pub recipes: Vec<String>,
+    pub sounds: Vec<String>,
+    pub damage_types: Vec<String>,
+    pub attributes: Vec<String>,
+    pub loot_tables: Vec<String>,
+    pub templates: Vec<String>,
+    pub random_sequences: Vec<String>,
+    pub datapacks_enabled: Vec<String>,
+    pub datapacks_disabled: Vec<String>,
+    pub function_tags: Vec<String>,
+    /// The block the source is looking at (relevant coordinates).
+    pub target_block: Option<[i32; 3]>,
+    /// `ClientSuggestionProvider.getAbsoluteCoordinates`: the exact point of
+    /// that block hit, each coordinate as `%.2f` (`Locale.ROOT`).
+    pub target_point: Option<[String; 3]>,
+    /// Every registry's element and tag ids (`minecraft:item` -> ...), as
+    /// the server's registry access and reloadable registries hold them.
+    pub by_registry: BTreeMap<String, RegistryIds>,
+    /// Blocks whose default state has a block entity.
+    pub block_entities: std::collections::BTreeSet<String>,
+    /// Block tag -> member blocks.
+    pub block_tag_members: BTreeMap<String, Vec<String>>,
+    /// Data component types with a codec (not transient).
+    pub persistent_components: Vec<String>,
+    /// Recipes `/recipe` can give (not special).
+    pub learnable_recipes: Vec<String>,
+    /// Advancement id -> criterion names.
+    pub advancement_criteria: BTreeMap<String, Vec<String>>,
+    /// World clock -> time markers shown in commands.
+    pub clock_time_markers: BTreeMap<String, Vec<String>>,
+    /// Trigger objectives the source may use (`/trigger` suggestions).
+    pub trigger_objectives: Vec<String>,
+    /// Objectives with the `trigger` criterion -> holder -> whether its score is locked.
+    pub trigger_scores: BTreeMap<String, BTreeMap<String, bool>>,
+}
+/// The ids and tag ids of one registry.
+#[derive(Clone, Debug, Default)]
+pub struct RegistryIds {
+    pub ids: Vec<String>,
+    pub tags: Vec<String>,
+}
+const EMPTY: &[String] = &[];
+impl Registries {
+    /// Fill what the game did not build itself from vanilla's exported
+    /// registries (`command-registries.json`, written by
+    /// `VanillaCommandParseOracle registries`): built-in registries such as
+    /// mob effects, data component types and dialogs, block entities and tag
+    /// members. Registries that data packs reload stay with the game.
+    pub fn fill_from_export(&mut self, r: &serde_json::Value) {
+        fn strings(v: &serde_json::Value) -> Vec<String> {
+            v.as_array()
+                .map(|a| {
+                    a.iter()
+                        .filter_map(|x| x.as_str().map(str::to_owned))
+                        .collect()
+                })
+                .unwrap_or_default()
+        }
+        let fill = |field: &mut Vec<String>, key: &str| {
+            if field.is_empty() {
+                *field = strings(&r[key]);
+            }
+        };
+        fill(&mut self.effects, "effects");
+        fill(&mut self.enchantments, "enchantments");
+        fill(&mut self.attributes, "attributes");
+        fill(&mut self.damage_types, "damage_types");
+        fill(&mut self.templates, "templates");
+        fill(&mut self.persistent_components, "persistent_components");
+        fill(&mut self.learnable_recipes, "learnable_recipes");
+        const RELOADED: [&str; 5] = [
+            "minecraft:advancement",
+            "minecraft:recipe",
+            "minecraft:loot_table",
+            "minecraft:predicate",
+            "minecraft:item_modifier",
+        ];
+        for (name, entry) in r["by_registry"].as_object().into_iter().flatten() {
+            if RELOADED.contains(&name.as_str()) || self.by_registry.contains_key(name) {
+                continue;
+            }
+            self.by_registry.insert(
+                name.clone(),
+                RegistryIds {
+                    ids: strings(&entry["ids"]),
+                    tags: strings(&entry["tags"]),
+                },
+            );
+        }
+        if self.block_entities.is_empty() {
+            self.block_entities = strings(&r["block_entities"]).into_iter().collect();
+        }
+        if self.block_tag_members.is_empty() {
+            for (tag, members) in r["block_tag_members"].as_object().into_iter().flatten() {
+                self.block_tag_members.insert(tag.clone(), strings(members));
+            }
+        }
+        if self.clock_time_markers.is_empty() {
+            for (clock, markers) in r["clock_time_markers"].as_object().into_iter().flatten() {
+                self.clock_time_markers
+                    .insert(clock.clone(), strings(markers));
+            }
+        }
+        if self.advancement_criteria.is_empty() {
+            for (id, criteria) in r["advancement_criteria"].as_object().into_iter().flatten() {
+                self.advancement_criteria
+                    .insert(id.clone(), strings(criteria));
+            }
+        }
+    }
+    /// The element ids of a registry (sorted).
+    pub fn ids(&self, registry: &str) -> &[String] {
+        if let Some(r) = self.by_registry.get(registry) {
+            return &r.ids;
+        }
+        match registry {
+            "minecraft:item" => &self.items,
+            "minecraft:entity_type" => &self.entity_types,
+            "minecraft:mob_effect" => &self.effects,
+            "minecraft:enchantment" => &self.enchantments,
+            "minecraft:worldgen/structure" => &self.structures,
+            "minecraft:worldgen/biome" => &self.biomes,
+            "minecraft:world_clock" => &self.clocks,
+            "minecraft:timeline" => &self.timelines,
+            "minecraft:attribute" => &self.attributes,
+            "minecraft:damage_type" => &self.damage_types,
+            "minecraft:sound_event" => &self.sounds,
+            "minecraft:predicate" => &self.predicates,
+            "minecraft:item_modifier" => &self.item_modifiers,
+            "minecraft:loot_table" => &self.loot_tables,
+            "minecraft:recipe" => &self.recipes,
+            "minecraft:advancement" => &self.advancements,
+            _ => EMPTY,
+        }
+    }
+    /// The tag ids of a registry (sorted).
+    pub fn tags(&self, registry: &str) -> &[String] {
+        if let Some(r) = self.by_registry.get(registry) {
+            return &r.tags;
+        }
+        match registry {
+            "minecraft:item" => &self.item_tags,
+            "minecraft:block" => &self.block_tags,
+            _ => EMPTY,
+        }
+    }
+}

crates/horizon-client-core/src/scoreboard.rs

@@ -2,9 +2,9 @@
 //! `ObjectiveCriteria`, `NumberFormat`) and its saved data
 //! (`data/minecraft/scoreboard.dat`, `ScoreboardSaveData.Packed`).
 use crate::{
-    command::Registries,
     component,
     fastutil_order::{HashSetOrder, OpenOrder},
+    registries::Registries,
     text::{self, Style, Text},
 };
 use horizon_world::nbt::Tag;
@@ -662,10 +662,22 @@ pub fn name_shown(own: Option<&Team>, viewer: Option<&Team>, v: NameView) -> boo
     }
     !v.hud_hidden && !v.is_camera && visible && !v.is_vehicle
 }
-/// `ServerPlayer.die`: whether a player's death message reaches the player
-/// themselves (the team broadcasts leave out the dying player).
-pub fn own_death_message_shown(team: Option<&Team>) -> bool {
-    team.is_none_or(|t| t.death_message_visibility == Visibility::Always)
+/// `ServerPlayer.die`: whether `other` hears the death message of `dying`
+/// (`broadcastSystemMessage`, `broadcastSystemToTeam` or
+/// `broadcastSystemToAllExceptTeam`, by the team's death message visibility).
+pub fn death_message_reaches(board: &Scoreboard, dying: &str, other: &str) -> bool {
+    let Some(team) = board.players_team(dying) else {
+        return true;
+    };
+    let same_team = board
+        .players_team(other)
+        .is_some_and(|t| t.name == team.name);
+    match team.death_message_visibility {
+        Visibility::Always => true,
+        Visibility::Never => false,
+        Visibility::HideForOtherTeams => same_team && other != dying,
+        Visibility::HideForOwnTeam => !same_team,
+    }
 }
 
 // ---- objectives and scores ---------------------------------------------
@@ -1266,7 +1278,7 @@ fn entity_uuids(tag: &mut Tag) {
                             })
                             .collect::<Option<Vec<i32>>>(),
                         Tag::String(s) => {
-                            crate::save::uuid_from_text(&s.to_string_lossy()).map(Vec::from)
+                            crate::uuid::uuid_from_text(&s.to_string_lossy()).map(Vec::from)
                         }
                         _ => None,
                     };

crates/horizon-client-core/src/sound_source.rs

@@ -0,0 +1,7 @@
+//! Sound sources (`SoundSource`), by name.
+
+/// SoundSource names in vanilla order.
+pub const SOUND_SOURCES: [&str; 11] = [
+    "master", "music", "record", "weather", "block", "hostile", "neutral", "player", "ambient",
+    "voice", "ui",
+];

crates/horizon-client-core/src/text.rs

@@ -42,8 +42,17 @@ pub fn named_color(name: &str) -> Option<u32> {
 /// Click actions carried by locally constructed text components.
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub enum ClickEvent {
+    /// `ClickEvent.OpenUrl`: an http or https link.
+    OpenUrl(String),
+    /// `ClickEvent.ChangePage`: a book's page, counted from 1.
+    ChangePage(i32),
     SuggestCommand(String),
+    /// `ClickEvent.RunCommand`: the command, with or without its `/`.
+    RunCommand(String),
     CopyToClipboard(String),
+    /// `ClickEvent.ShowDialog`: a `minecraft:dialog` registry id, or the
+    /// dialog itself as the component carried it.
+    ShowDialog(horizon_world::nbt::Tag),
     /// A local file to open with the system handler.
     /// Only allow this in locally constructed messages, never server/LAN text.
     OpenFile(String),
@@ -61,13 +70,17 @@ pub struct Style {
     pub click: Option<ClickEvent>,
     /// Hover text.
     pub hover: Option<Box<Text>>,
+    /// `HoverEvent.ShowItem`: the event's `{id, count?, components?}` object.
+    pub hover_item: Option<Box<Value>>,
+    /// `Style.insertion`: the text a Shift-click puts in the chat box.
+    pub insertion: Option<String>,
     /// The font (`FontDescription.Resource`), a full id like
     /// `minecraft:alt`; the default font when unset.
     pub font: Option<String>,
 }
 /// A style's `font` field: an identifier (`alt` is `minecraft:alt`).
 pub fn font_id(v: &Value) -> Option<String> {
-    crate::command::args::parse_identifier(v.as_str()?)
+    crate::identifier::parse_identifier(v.as_str()?)
 }
 impl Style {
     pub fn color(c: u32) -> Self {
@@ -90,6 +103,12 @@ impl Style {
         if self.hover.is_none() {
             self.hover.clone_from(&base.hover);
         }
+        if self.hover_item.is_none() {
+            self.hover_item.clone_from(&base.hover_item);
+        }
+        if self.insertion.is_none() {
+            self.insertion.clone_from(&base.insertion);
+        }
         if self.font.is_none() {
             self.font.clone_from(&base.font);
         }
@@ -384,31 +403,7 @@ impl Text {
                     continue;
                 }
                 let Some(code) = chars.next() else { break };
-                let code = code.to_ascii_lowercase();
-                let next = if let Some(c) = COLORS.iter().find(|c| c.0 == code) {
-                    // Style.applyLegacyFormat: a colour clears the decorations.
-                    Style {
-                        color: Some(c.2),
-                        bold: Some(false),
-                        italic: Some(false),
-                        underlined: Some(false),
-                        strikethrough: Some(false),
-                        obfuscated: Some(false),
-                        ..style.clone()
-                    }
-                } else {
-                    let mut s = style.clone();
-                    match code {
-                        'k' => s.obfuscated = Some(true),
-                        'l' => s.bold = Some(true),
-                        'm' => s.strikethrough = Some(true),
-                        'n' => s.underlined = Some(true),
-                        'o' => s.italic = Some(true),
-                        'r' => s = span.style.clone(),
-                        _ => {}
-                    }
-                    s
-                };
+                let next = legacy_format(&style, code, &span.style);
                 if next != style {
                     if !current.is_empty() {
                         out.spans.push(Span {
@@ -495,7 +490,7 @@ impl Text {
 }
 
 /// The style fields of a component's JSON.
-const STYLE_KEYS: [&str; 9] = [
+const STYLE_KEYS: [&str; 10] = [
     "color",
     "bold",
     "italic",
@@ -504,6 +499,7 @@ const STYLE_KEYS: [&str; 9] = [
     "obfuscated",
     "click_event",
     "hover_event",
+    "insertion",
     "font",
 ];
 /// Style.Serializer: the fields a style sets.
@@ -529,12 +525,22 @@ fn style_json(style: &Style) -> Vec<(String, Value)> {
     }
     if let Some(click) = &style.click {
         let event = match click {
+            ClickEvent::OpenUrl(url) => json!({ "action": "open_url", "url": url }),
+            ClickEvent::ChangePage(page) => json!({ "action": "change_page", "page": page }),
             ClickEvent::SuggestCommand(command) => {
                 json!({ "action": "suggest_command", "command": command })
             }
             ClickEvent::CopyToClipboard(value) => {
                 json!({ "action": "copy_to_clipboard", "value": value })
             }
+            ClickEvent::RunCommand(command) => {
+                json!({ "action": "run_command", "command": command })
+            }
+            // ClickEvent.ShowDialog.CODEC: the dialog the server sent it with.
+            ClickEvent::ShowDialog(dialog) => json!({
+                "action": "show_dialog",
+                "dialog": crate::scoreboard::tag_to_json(dialog),
+            }),
             ClickEvent::OpenFile(path) => json!({ "action": "open_file", "path": path }),
         };
         out.push(("click_event".to_owned(), event));
@@ -544,6 +550,13 @@ fn style_json(style: &Style) -> Vec<(String, Value)> {
             "hover_event".to_owned(),
             json!({ "action": "show_text", "value": hover.component() }),
         ));
+    } else if let Some(Value::Object(item)) = style.hover_item.as_deref() {
+        let mut event = item.clone();
+        event.insert("action".into(), "show_item".into());
+        out.push(("hover_event".to_owned(), Value::Object(event)));
+    }
+    if let Some(insertion) = &style.insertion {
+        out.push(("insertion".to_owned(), insertion.clone().into()));
     }
     if let Some(font) = &style.font {
         out.push(("font".to_owned(), font.clone().into()));
@@ -551,6 +564,35 @@ fn style_json(style: &Style) -> Vec<(String, Value)> {
     out
 }
 
+/// `Style.applyLegacyFormat` for the code after a `§`, `§r` going back to
+/// `reset` (`StringDecomposer.iterateFormatted`); an unknown code changes nothing.
+pub fn legacy_format(style: &Style, code: char, reset: &Style) -> Style {
+    let code = code.to_ascii_lowercase();
+    if let Some(c) = COLORS.iter().find(|c| c.0 == code) {
+        // A colour clears the decorations.
+        return Style {
+            color: Some(c.2),
+            bold: Some(false),
+            italic: Some(false),
+            underlined: Some(false),
+            strikethrough: Some(false),
+            obfuscated: Some(false),
+            ..style.clone()
+        };
+    }
+    let mut s = style.clone();
+    match code {
+        'k' => s.obfuscated = Some(true),
+        'l' => s.bold = Some(true),
+        'm' => s.strikethrough = Some(true),
+        'n' => s.underlined = Some(true),
+        'o' => s.italic = Some(true),
+        'r' => s = reset.clone(),
+        _ => {}
+    }
+    s
+}
+
 /// TranslatableContents.decomposeTemplate: `%s` takes the next argument,
 /// `%n$s` a numbered one and `%%` is a percent sign. Malformed templates are
 /// shown verbatim.

crates/horizon-client-core/src/uuid.rs

@@ -0,0 +1,24 @@
+//! UUIDs as vanilla's four-int form, to and from their text form.
+
+pub fn uuid_text(u: [i32; 4]) -> String {
+    let hex: String = u.iter().map(|v| format!("{:08x}", *v as u32)).collect();
+    format!(
+        "{}-{}-{}-{}-{}",
+        &hex[0..8],
+        &hex[8..12],
+        &hex[12..16],
+        &hex[16..20],
+        &hex[20..32]
+    )
+}
+pub fn uuid_from_text(s: &str) -> Option<[i32; 4]> {
+    let hex: String = s.chars().filter(|c| *c != '-').collect();
+    if hex.len() != 32 {
+        return None;
+    }
+    let mut out = [0i32; 4];
+    for (i, v) in out.iter_mut().enumerate() {
+        *v = u32::from_str_radix(&hex[i * 8..i * 8 + 8], 16).ok()? as i32;
+    }
+    Some(out)
+}

crates/horizon-client-core/src/who.rs

@@ -0,0 +1,8 @@
+//! Who an action came from or is aimed at: the player or a mob by id.
+
+/// Who caused damage or is being targeted.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum Who {
+    Player,
+    Mob(u32),
+}

crates/horizon-client-input/Cargo.toml

@@ -0,0 +1,23 @@
+[package]
+name = "horizon-client-input"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+rust-version = "1.90"
+description = "The client's input layer: key bindings and their names, mouse, controllers, clipboard and window options"
+
+[dependencies]
+horizon-client-core = { path = "../horizon-client-core" }
+winit = "0.30.13"
+# The window icon.
+horizon-theme = { path = "../horizon-theme" }
+png = "0.18"
+arboard = { version = "3.6.1", default-features = false, features = ["wayland-data-control"] }
+# The DualSense's trigger effects (the `controllers` feature).
+horizon-dualsense = { path = "../horizon-dualsense", optional = true }
+
+[features]
+controllers = ["dep:horizon-dualsense"]
+
+[lints]
+workspace = true

crates/horizon-client-input/src/keybinds.rs

@@ -2,7 +2,6 @@
 //! defaults, `key_<name>:key.keyboard.x` persistence, display names, and the
 //! translation of rebound physical keys back to the default keys the game
 //! logic listens for.
-use crate::text::Text;
 use std::collections::BTreeMap;
 use winit::{event::MouseButton, keyboard::KeyCode};
 
@@ -146,6 +145,22 @@ const KEYS: &[(&str, KeyCode)] = &[
     ("key.keyboard.period", KeyCode::Period),
     ("key.keyboard.slash", KeyCode::Slash),
     ("key.keyboard.caps.lock", KeyCode::CapsLock),
+    ("key.keyboard.world.1", KeyCode::IntlBackslash),
+    ("key.keyboard.international1", KeyCode::IntlRo),
+    ("key.keyboard.international3", KeyCode::IntlYen),
+    ("key.keyboard.lang1", KeyCode::Lang1),
+    ("key.keyboard.lang2", KeyCode::Lang2),
+    ("key.keyboard.lang3", KeyCode::Lang3),
+    ("key.keyboard.lang4", KeyCode::Lang4),
+    ("key.keyboard.lang5", KeyCode::Lang5),
+    ("key.keyboard.help", KeyCode::Help),
+    ("key.keyboard.select", KeyCode::Select),
+    ("key.keyboard.again", KeyCode::Again),
+    ("key.keyboard.undo", KeyCode::Undo),
+    ("key.keyboard.cut", KeyCode::Cut),
+    ("key.keyboard.copy", KeyCode::Copy),
+    ("key.keyboard.paste", KeyCode::Paste),
+    ("key.keyboard.find", KeyCode::Find),
     ("key.keyboard.f1", KeyCode::F1),
     ("key.keyboard.f2", KeyCode::F2),
     ("key.keyboard.f3", KeyCode::F3),
@@ -158,6 +173,18 @@ const KEYS: &[(&str, KeyCode)] = &[
     ("key.keyboard.f10", KeyCode::F10),
     ("key.keyboard.f11", KeyCode::F11),
     ("key.keyboard.f12", KeyCode::F12),
+    ("key.keyboard.f13", KeyCode::F13),
+    ("key.keyboard.f14", KeyCode::F14),
+    ("key.keyboard.f15", KeyCode::F15),
+    ("key.keyboard.f16", KeyCode::F16),
+    ("key.keyboard.f17", KeyCode::F17),
+    ("key.keyboard.f18", KeyCode::F18),
+    ("key.keyboard.f19", KeyCode::F19),
+    ("key.keyboard.f20", KeyCode::F20),
+    ("key.keyboard.f21", KeyCode::F21),
+    ("key.keyboard.f22", KeyCode::F22),
+    ("key.keyboard.f23", KeyCode::F23),
+    ("key.keyboard.f24", KeyCode::F24),
     ("key.keyboard.print.screen", KeyCode::PrintScreen),
     ("key.keyboard.scroll.lock", KeyCode::ScrollLock),
     ("key.keyboard.pause", KeyCode::Pause),
@@ -189,6 +216,36 @@ const KEYS: &[(&str, KeyCode)] = &[
     ("key.keyboard.keypad.0", KeyCode::Numpad0),
     ("key.keyboard.keypad.period", KeyCode::NumpadDecimal),
     ("key.keyboard.keypad.equal", KeyCode::NumpadEqual),
+    ("key.keyboard.keypad.comma", KeyCode::NumpadComma),
+    ("key.keyboard.keypad.backspace", KeyCode::NumpadBackspace),
+    (
+        "key.keyboard.keypad.left.parenthesis",
+        KeyCode::NumpadParenLeft,
+    ),
+    (
+        "key.keyboard.keypad.right.parenthesis",
+        KeyCode::NumpadParenRight,
+    ),
+    ("key.keyboard.keypad.hash", KeyCode::NumpadHash),
+    (
+        "key.keyboard.keypad.memory.store",
+        KeyCode::NumpadMemoryStore,
+    ),
+    (
+        "key.keyboard.keypad.memory.recall",
+        KeyCode::NumpadMemoryRecall,
+    ),
+    (
+        "key.keyboard.keypad.memory.clear",
+        KeyCode::NumpadMemoryClear,
+    ),
+    ("key.keyboard.keypad.memory.add", KeyCode::NumpadMemoryAdd),
+    (
+        "key.keyboard.keypad.memory.subtract",
+        KeyCode::NumpadMemorySubtract,
+    ),
+    ("key.keyboard.keypad.clear", KeyCode::NumpadClear),
+    ("key.keyboard.keypad.clear.entry", KeyCode::NumpadClearEntry),
     ("key.keyboard.menu", KeyCode::ContextMenu),
     ("key.keyboard.left.control", KeyCode::ControlLeft),
     ("key.keyboard.left.shift", KeyCode::ShiftLeft),
@@ -225,40 +282,7 @@ pub fn mouse_button(name: &str) -> Option<MouseButton> {
         _ => return None,
     })
 }
-/// InputConstants.Key.getDisplayName: one-character keys as the upper-case
-/// character, others by translation.
-pub fn display_name(key: &str) -> Text {
-    if let Some(rest) = key.strip_prefix("key.keyboard.")
-        && rest.chars().count() == 1
-    {
-        let c = rest.to_uppercase();
-        return Text::literal(c);
-    }
-    let symbol = match key {
-        "key.keyboard.minus" => Some("-"),
-        "key.keyboard.equal" => Some("="),
-        "key.keyboard.left.bracket" => Some("["),
-        "key.keyboard.right.bracket" => Some("]"),
-        "key.keyboard.backslash" => Some("\\"),
-        "key.keyboard.semicolon" => Some(";"),
-        "key.keyboard.apostrophe" => Some("'"),
-        "key.keyboard.grave.accent" => Some("`"),
-        "key.keyboard.comma" => Some(","),
-        "key.keyboard.period" => Some("."),
-        "key.keyboard.slash" => Some("/"),
-        _ => None,
-    };
-    if let Some(s) = symbol {
-        return Text::literal(s);
-    }
-    if let Some(n) = key.strip_prefix("key.mouse.")
-        && n.parse::<u32>().is_ok()
-        && !crate::lang::has(key)
-    {
-        return Text::translate("key.mouse", &[Text::literal(n)]);
-    }
-    Text::translate(key, &[])
-}
+pub use horizon_client_core::key_display::display_name;
 
 /// Current bindings by mapping name.
 #[derive(Clone, Debug, PartialEq, Eq)]
@@ -276,9 +300,8 @@ impl Default for KeyBinds {
     }
 }
 /// Each default key once, in order: two mappings that share a default key
-/// (Advancements and the debug profiler both on L) are one press of it, not
-/// two (the second would close the screen the first opened). Vanilla clicks
-/// both mappings, but the profiler one only acts with F3 held.
+/// (Pick Block and the spectator hotbar both on the middle button) are one
+/// press of it, not two.
 fn distinct<T: PartialEq>(keys: Vec<T>) -> Vec<T> {
     let mut out = Vec::with_capacity(keys.len());
     for k in keys {
@@ -344,6 +367,25 @@ impl KeyBinds {
             .map(|m| m.0)
             .filter(move |n| self.get(n) == key)
     }
+    /// The mappings bound to `key` that [`KeyBinds::translate_all`] follows:
+    /// all but the debug keys. Those act only with F3 held
+    /// (`KeyboardHandler.handleDebugKeys`, `debug_keys.rs` reads the physical
+    /// key and the binding itself); their defaults (A, S, D, T, L, 1 to 4...)
+    /// would otherwise turn the key back into its old gameplay meaning.
+    fn translated_mappings<'a>(&'a self, key: &'a str) -> impl Iterator<Item = &'static str> + 'a {
+        MAPPINGS
+            .iter()
+            .filter(|m| m.2 != "debug")
+            .map(|m| m.0)
+            .filter(move |n| self.get(n) == key)
+    }
+    /// Whether a mapping (other than a debug key) whose default is `key` was
+    /// bound elsewhere.
+    fn default_moved(&self, key: &str) -> bool {
+        MAPPINGS
+            .iter()
+            .any(|(n, d, c)| *d == key && *c != "debug" && !self.is_default(n))
+    }
     /// Translate a physical key into the default key of the mapping it is
     /// bound to, so game code written against vanilla defaults follows the
     /// player's bindings. `None` means the key now does nothing; mouse
@@ -360,7 +402,7 @@ impl KeyBinds {
             return vec![Ok(key)];
         };
         let bound: Vec<_> = self
-            .mappings_for(name)
+            .translated_mappings(name)
             .filter_map(|mapping| {
                 let default = Self::default_of(mapping);
                 match key_code(default) {
@@ -373,10 +415,7 @@ impl KeyBinds {
             return distinct(bound);
         }
         // An unbound key whose default meaning was moved elsewhere is inert.
-        if MAPPINGS
-            .iter()
-            .any(|(n, d, _)| *d == name && !self.is_default(n))
-        {
+        if self.default_moved(name) {
             return Vec::new();
         }
         vec![Ok(key)]
@@ -389,7 +428,7 @@ impl KeyBinds {
     pub fn translate_mouse_all(&self, button: MouseButton) -> Vec<Result<KeyCode, MouseButton>> {
         let name = mouse_name(button);
         let bound: Vec<_> = self
-            .mappings_for(&name)
+            .translated_mappings(&name)
             .filter_map(|mapping| {
                 let default = Self::default_of(mapping);
                 match mouse_button(default) {
@@ -401,10 +440,7 @@ impl KeyBinds {
         if !bound.is_empty() {
             return distinct(bound);
         }
-        if MAPPINGS
-            .iter()
-            .any(|(n, d, _)| *d == name && !self.is_default(n))
-        {
+        if self.default_moved(&name) {
             return Vec::new();
         }
         vec![Err(button)]
@@ -484,6 +520,29 @@ mod tests {
         assert_eq!(k.conflicts("key.forward"), ["key.jump"]);
     }
     #[test]
+    fn a_moved_key_keeps_no_default_action() {
+        // #3158: the debug keys (F3+A, F3+1...) share these keys' defaults,
+        // and must not hand them back their gameplay meaning.
+        let mut k = KeyBinds::default();
+        k.set("key.hotbar.1", "key.keyboard.q");
+        assert_eq!(k.translate_all(KeyCode::Digit1), []);
+        assert_eq!(
+            k.translate_all(KeyCode::KeyQ),
+            [Ok(KeyCode::KeyQ), Ok(KeyCode::Digit1)]
+        );
+        k.set("key.inventory", "key.keyboard.a");
+        k.set("key.left", "key.keyboard.e");
+        assert_eq!(k.translate_all(KeyCode::KeyA), [Ok(KeyCode::KeyE)]);
+        assert_eq!(k.translate_all(KeyCode::KeyE), [Ok(KeyCode::KeyA)]);
+        k.set("key.back", "key.keyboard.down");
+        assert_eq!(k.translate_all(KeyCode::KeyS), []);
+        // Keys left alone still act, and a moved debug key changes nothing.
+        k.set("key.debug.fpsCharts", "key.keyboard.9");
+        assert_eq!(k.translate_all(KeyCode::Digit2), [Ok(KeyCode::Digit2)]);
+        assert_eq!(k.translate_all(KeyCode::Digit9), [Ok(KeyCode::Digit9)]);
+        assert_eq!(k.translate_all(KeyCode::F3), [Ok(KeyCode::F3)]);
+    }
+    #[test]
     fn display_names() {
         assert_eq!(display_name("key.keyboard.w").plain(), "W");
         assert_eq!(display_name("key.keyboard.slash").plain(), "/");

crates/horizon-client-input/src/lib.rs

@@ -0,0 +1,14 @@
+//! The client's input layer, below gameplay and screens: key bindings and their
+//! names, toggle keys, mouse settings, controllers, the clipboard and window
+//! options. horizon-client re-exports each module under its old path
+//! (`horizon_client::keybinds`, ...).
+#![forbid(unsafe_code)]
+pub mod clipboard;
+pub mod gamepad;
+pub mod input;
+pub mod interaction_input;
+pub mod key_names;
+pub mod keybinds;
+pub mod keymapping;
+pub mod mouse;
+pub mod window;

crates/horizon-client-input/src/mouse.rs

@@ -324,6 +324,24 @@ pub fn ease_in_out(t: f64) -> f64 {
     0.5 - 0.5 * (std::f64::consts::PI * t).cos()
 }
 
+/// `MouseHandler.grabMouse` / `releaseMouse`: the mouse position is the
+/// window's centre whenever the pointer's grab state changes, so a screen
+/// opened from gameplay starts with the cursor in the middle. A release of
+/// an already free pointer (or a grab of an already grabbed one) leaves the
+/// position where it is, as vanilla does.
+pub fn mouse_position_after_grab_change(
+    grab: bool,
+    was_grabbed: bool,
+    size: [u32; 2],
+    scale: f32,
+) -> Option<(f32, f32)> {
+    if grab == was_grabbed {
+        None
+    } else {
+        Some((size[0] as f32 / 2.0 / scale, size[1] as f32 / 2.0 / scale))
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -485,4 +503,27 @@ mod tests {
         assert_eq!(look.on_scroll(0.0, 0.4, false, 1.0), None);
         assert_eq!(look.on_scroll(0.0, 0.7, false, 1.0), Some((1, (0, 1))));
     }
+    #[test]
+    fn the_mouse_position_is_the_centre_when_the_grab_changes() {
+        // A grab of a free pointer and a release of a grabbed one both put
+        // the position at the window's centre (`MouseHandler.grabMouse`,
+        // `MouseHandler.releaseMouse`).
+        assert_eq!(
+            mouse_position_after_grab_change(true, false, [1920, 1080], 1.0),
+            Some((960.0, 540.0))
+        );
+        assert_eq!(
+            mouse_position_after_grab_change(false, true, [1920, 1080], 2.0),
+            Some((480.0, 270.0))
+        );
+        // Without a change of the grab state the position stays where it is.
+        assert_eq!(
+            mouse_position_after_grab_change(false, false, [1920, 1080], 1.0),
+            None
+        );
+        assert_eq!(
+            mouse_position_after_grab_change(true, true, [1920, 1080], 1.0),
+            None
+        );
+    }
 }

crates/horizon-client-render/Cargo.toml

@@ -0,0 +1,67 @@
+[package]
+name = "horizon-client-render"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+rust-version = "1.90"
+description = "The client's world data, rendering and screens: chunks, meshing, light, streaming, the renderer, the HUD, menus and settings; no gameplay"
+
+[dependencies]
+horizon-assets = { path = "../horizon-assets" }
+horizon-bench = { path = "../horizon-bench" }
+horizon-client-core = { path = "../horizon-client-core" }
+horizon-client-input = { path = "../horizon-client-input" }
+horizon-command = { path = "../horizon-command" }
+horizon-core = { path = "../horizon-core" }
+horizon-hdr = { path = "../horizon-hdr" }
+horizon-items = { path = "../horizon-items" }
+horizon-protocol = { path = "../horizon-protocol" }
+horizon-shader-api = { path = "../horizon-shader-api" }
+horizon-shaders = { path = "../horizon-shaders" }
+horizon-telemetry = { path = "../horizon-telemetry", default-features = false, features = ["live"] }
+horizon-theme = { path = "../horizon-theme" }
+horizon-threads = { path = "../horizon-threads" }
+horizon-world = { path = "../horizon-world" }
+ab_glyph = "0.2.32"
+bytemuck = { version = "1.24", features = ["derive"] }
+# Sound (ALSA on Linux); the `audio` feature.
+cpal = { version = "0.16", optional = true }
+chrono = { version = "0.4.42", default-features = false, features = ["clock", "std"] }
+flate2 = { version = "1.1.10", default-features = false, features = ["zlib-rs", "runtime_detection"] }
+glam = "0.30"
+log = "0.4"
+miniz_oxide = "0.8"
+naga = { version = "30.0.1", features = ["wgsl-in", "hlsl-out"] }
+png = "0.18"
+pollster = "0.4"
+serde = { version = "1", features = ["derive"] }
+serde_json = { version = "1.0.151", features = ["raw_value"] }
+sha2 = "0.10.9"
+symphonia = { version = "0.5", default-features = false, features = ["ogg", "vorbis"] }
+unicode-bidi = "0.3.18"
+ureq = { version = "2", default-features = false, features = ["tls"] }
+wgpu = { version = "30.0.1", default-features = false, features = ["std", "parking_lot", "vulkan", "metal", "wgsl", "naga-ir"] }
+winit = "0.30.13"
+zip = { version = "2", default-features = false, features = ["deflate"] }
+
+[target.'cfg(unix)'.dependencies]
+rustix = { version = "1", default-features = false, features = ["std", "time"] }
+
+[target.'cfg(windows)'.dependencies]
+wgpu = { version = "30.0.1", default-features = false, features = ["dx12"] }
+
+[target.'cfg(not(target_os = "macos"))'.dependencies]
+wgpu = { version = "30.0.1", default-features = false, features = ["gles"] }
+
+[features]
+# Sound output: horizon-client's `audio` feature.
+audio = ["dep:cpal"]
+# Helpers horizon-client's tests build their fixtures with.
+test-support = []
+
+[lints]
+workspace = true
+
+[dev-dependencies]
+horizon-items = { path = "../horizon-items", features = ["test-support"] }
+naga = { version = "30.0.1", features = ["wgsl-in", "hlsl-out", "msl-out", "spv-out"] }

crates/horizon-client-render/src/assets.rs

@@ -42,11 +42,11 @@ impl HeightmapState for StateFacts {
 }
 #[derive(Clone)]
 pub struct Properties(Arc<Vec<StateFacts>>);
-#[cfg(test)]
+#[cfg(any(test, feature = "test-support"))]
 impl Properties {
     /// Heightmap facts for tests, per state: (air, has a fluid, blocks
     /// motion, blocks motion but is not leaves). State 0 is minecraft:air.
-    pub(crate) fn for_tests(states: &[(bool, bool, bool, bool)]) -> Self {
+    pub fn for_tests(states: &[(bool, bool, bool, bool)]) -> Self {
         Self(Arc::new(
             states
                 .iter()
@@ -196,7 +196,7 @@ impl Assets {
 impl RenderAssets {
     pub fn load(root: &Path, assets: &Assets) -> Result<Self> {
         let registry = assets.registry;
-        let mut sprites = crate::sprites::Sprites::default();
+        let mut sprites = crate::sprites::Sprites::with_disk_cache(root);
         for name in MATERIALS {
             sprites.insert(root, &format!("minecraft:block/{name}"))?;
         }
@@ -217,7 +217,10 @@ impl RenderAssets {
         for stage in 0..10 {
             sprites.insert(root, &format!("minecraft:block/destroy_stage_{stage}"))?;
         }
+        sprites.save_disk_cache();
         sprites.finish();
+        // `finish` grows the buffer by doubling: keep only the bytes in use.
+        sprites.pixels.shrink_to_fit();
         Ok(Self {
             sprite_size: sprites.size,
             sprite_minimum_size: sprites.minimum_size,
@@ -234,3 +237,81 @@ impl RenderAssets {
         })
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use crate::items::ConsumeEffect;
+
+    #[test]
+    fn always_edible_and_consume_effects_loaded() {
+        let root = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .join("../../.local/horizon-client/26.3");
+        if !root.join("items.json").exists() {
+            return;
+        }
+        let assets = crate::assets::Assets::load(&root).unwrap();
+        let facts = crate::blocks::BlockFacts::load(&root, assets.registry).unwrap();
+        let items = crate::items::Items::load(&root, assets.registry, &facts).unwrap();
+
+        let apple = items.get("minecraft:golden_apple").expect("golden apple");
+        assert!(apple.can_always_eat);
+        assert!(apple.food.is_some());
+        assert!(!apple.consumable.as_ref().unwrap().effects.is_empty());
+
+        let enchanted = items
+            .get("minecraft:enchanted_golden_apple")
+            .expect("enchanted golden apple");
+        assert!(enchanted.can_always_eat);
+        assert!(enchanted.food.is_some());
+        assert!(!enchanted.consumable.as_ref().unwrap().effects.is_empty());
+
+        let beef = items.get("minecraft:cooked_beef").expect("cooked beef");
+        assert!(!beef.can_always_eat);
+        assert!(beef.food.is_some());
+
+        // Consumables without food, their style and their remainders.
+        use horizon_world::consumable::UseAnimation;
+        let milk = items.get("minecraft:milk_bucket").expect("milk bucket");
+        let drink = milk.consumable.as_ref().unwrap();
+        assert!(milk.food.is_none());
+        assert_eq!(drink.effects, [ConsumeEffect::ClearAllEffects]);
+        assert_eq!((drink.ticks(), drink.animation), (32, UseAnimation::Drink));
+        assert_eq!(drink.sound, "minecraft:entity.generic.drink");
+        assert!(!drink.particles);
+        assert_eq!(milk.use_remainder.as_deref(), Some("minecraft:bucket"));
+        let honey = items.get("minecraft:honey_bottle").expect("honey bottle");
+        let sip = honey.consumable.as_ref().unwrap();
+        assert_eq!(sip.ticks(), 40);
+        assert_eq!(sip.sound, "minecraft:item.honey_bottle.drink");
+        assert_eq!(
+            sip.effects,
+            [ConsumeEffect::RemoveEffects(vec![
+                "minecraft:poison".into()
+            ])]
+        );
+        assert_eq!(
+            honey.use_remainder.as_deref(),
+            Some("minecraft:glass_bottle")
+        );
+        let kelp = items.get("minecraft:dried_kelp").unwrap();
+        let bite = kelp.consumable.as_ref().unwrap();
+        assert_eq!((bite.ticks(), bite.animation), (16, UseAnimation::Eat));
+        assert_eq!(bite.sound, "minecraft:entity.generic.eat");
+        assert!(bite.particles && kelp.use_remainder.is_none());
+        let chorus = items.get("minecraft:chorus_fruit").unwrap();
+        assert_eq!(
+            chorus.consumable.as_ref().unwrap().effects,
+            [ConsumeEffect::TeleportRandomly(
+                horizon_world::teleport_consume::TeleportConsume {
+                    diameter: 16.0,
+                    directional_particles: true,
+                }
+            )]
+        );
+        let chicken = items.get("minecraft:chicken").unwrap();
+        assert!(matches!(
+            chicken.consumable.as_ref().unwrap().effects[..],
+            [ConsumeEffect::ApplyEffects { probability, .. }] if probability == 0.3
+        ));
+    }
+}

crates/horizon-client-render/src/atlas_sources.rs

@@ -3,8 +3,8 @@
 //! `filter`, `unstitch` and `paletted_permutations` sources run in order
 //! against the resource tree; a later source replaces an earlier sprite of
 //! the same id and a filter removes the matching ones.
-use crate::packs::pattern::Pattern;
 use horizon_assets::palette::apply_palette;
+use horizon_client_core::pattern::Pattern;
 use serde_json::Value;
 use std::{
     collections::BTreeMap,
@@ -187,7 +187,14 @@ pub fn list_textures(root: &Path) -> Vec<String> {
             };
             for e in entries.flatten() {
                 let p = e.path();
-                if p.is_dir() {
+                // `file_type` comes with the listing; `Path::is_dir` is a stat per
+                // entry, kept for links (which it follows).
+                let dir = match e.file_type() {
+                    Ok(t) if t.is_symlink() => p.is_dir(),
+                    Ok(t) => t.is_dir(),
+                    Err(_) => p.is_dir(),
+                };
+                if dir {
                     stack.push(p);
                 } else if p.extension().is_some_and(|x| x == "png")
                     && let Ok(rel) = p.strip_prefix(&base)

crates/horizon-client-render/src/audio.rs

@@ -719,11 +719,6 @@ impl Audio {
         self.play(event, at, volume, pitch);
         self.capture = capture;
     }
-    /// `LivingEntity.handleDamageEvent`'s pitch, `(r - r) * 0.2 + 1`, drawn on the
-    /// client (the entity's own random there, never the server's world random).
-    pub fn hurt_pitch(&mut self) -> f32 {
-        (self.random.next_float() - self.random.next_float()) * 0.2 + 1.0
-    }
     /// `AbstractWidget.playButtonClickSound`: an unseeded, relative UI sound.
     pub fn play_button_click(&mut self) {
         self.play_instance(

crates/horizon-client-render/src/auth.rs

@@ -179,7 +179,7 @@ fn agent() -> ureq::Agent {
 }
 
 /// The discovery document, fetched once per game (a failure is retried next time).
-fn discovery() -> Result<Arc<serde_json::Value>, JoinError> {
+pub(crate) fn discovery() -> Result<Arc<serde_json::Value>, JoinError> {
     static CACHE: Mutex<Option<Arc<serde_json::Value>>> = Mutex::new(None);
     if let Some(d) = CACHE.lock().unwrap().clone() {
         return Ok(d);

crates/horizon-client-render/src/bidi.rs

@@ -0,0 +1,302 @@
+//! Right-to-left text (`FormattedBidiReorder.reorder`, behind
+//! `Language.getVisualOrder`): the logical text a player types becomes the
+//! glyphs a font draws left to right. Arabic letters are shaped into their
+//! joined presentation forms (ICU's `ArabicShaping` with `LETTERS_SHAPE`), the
+//! text is reordered by the Unicode bidirectional algorithm, and characters in
+//! right-to-left runs are mirrored. Left-to-right text comes back unchanged.
+use crate::text::{Span, Text};
+use std::borrow::Cow;
+use unicode_bidi::{
+    BidiClass, Direction, Level, ParagraphBidiInfo, bidi_class, get_base_direction,
+};
+
+/// How a letter joins its neighbours, as ICU's shaper sees it: `Right` joins
+/// the letter before it only, `Dual` both neighbours, `Mark` is skipped over
+/// (diacritics) and `None` never joins.
+#[derive(Clone, Copy, PartialEq)]
+enum Join {
+    None,
+    Right,
+    Dual,
+    Mark,
+}
+use Join::{Dual, Mark, Right};
+
+/// ICU's joining table (`araLink`): code point ranges and their class, with the
+/// lam-alef ligatures at the end. Anything else is `Join::None`.
+const JOINS: &[(u32, u32, Join)] = &[
+    (0x0622, 0x0625, Right),
+    (0x0626, 0x0626, Dual),
+    (0x0627, 0x0627, Right),
+    (0x0628, 0x0628, Dual),
+    (0x0629, 0x0629, Right),
+    (0x062A, 0x062E, Dual),
+    (0x062F, 0x0632, Right),
+    (0x0633, 0x063A, Dual),
+    (0x0640, 0x0647, Dual),
+    (0x0648, 0x0649, Right),
+    (0x064A, 0x064A, Dual),
+    (0x064B, 0x0656, Mark),
+    (0x0670, 0x0670, Mark),
+    (0x0671, 0x0673, Right),
+    (0x0675, 0x0677, Right),
+    (0x0678, 0x0687, Dual),
+    (0x0688, 0x0699, Right),
+    (0x069A, 0x06B9, Dual),
+    (0x06BA, 0x06BA, Right),
+    (0x06BB, 0x06BF, Dual),
+    (0x06C0, 0x06C0, Right),
+    (0x06C1, 0x06C1, Dual),
+    (0x06C2, 0x06CB, Right),
+    (0x06CC, 0x06CC, Dual),
+    (0x06CD, 0x06CD, Right),
+    (0x06CE, 0x06D1, Dual),
+    (0x06D2, 0x06D3, Right),
+    (0x200D, 0x200D, Dual),
+    (0x206D, 0x206F, Mark),
+    (0xFEF5, 0xFEFC, Right),
+];
+
+/// Letters that have joined forms and the code point of the isolated one; the
+/// final, initial and medial forms follow it (a right-joining letter has the
+/// isolated and final only). The lam-alef ligatures are their own letters.
+/// ICU leaves the extended letters (پ چ ژ ک گ ی and the rest of U+0679 to
+/// U+06D3) unchanged, so they are in `JOINS` but not here.
+#[rustfmt::skip]
+const FORMS: &[(u32, u32)] = &[
+    (0x0622, 0xFE81), (0x0623, 0xFE83), (0x0624, 0xFE85), (0x0625, 0xFE87), (0x0626, 0xFE89),
+    (0x0627, 0xFE8D), (0x0628, 0xFE8F), (0x0629, 0xFE93), (0x062A, 0xFE95), (0x062B, 0xFE99),
+    (0x062C, 0xFE9D), (0x062D, 0xFEA1), (0x062E, 0xFEA5), (0x062F, 0xFEA9), (0x0630, 0xFEAB),
+    (0x0631, 0xFEAD), (0x0632, 0xFEAF), (0x0633, 0xFEB1), (0x0634, 0xFEB5), (0x0635, 0xFEB9),
+    (0x0636, 0xFEBD), (0x0637, 0xFEC1), (0x0638, 0xFEC5), (0x0639, 0xFEC9), (0x063A, 0xFECD),
+    (0x0641, 0xFED1), (0x0642, 0xFED5), (0x0643, 0xFED9), (0x0644, 0xFEDD), (0x0645, 0xFEE1),
+    (0x0646, 0xFEE5), (0x0647, 0xFEE9), (0x0648, 0xFEED), (0x0649, 0xFEEF), (0x064A, 0xFEF1),
+    (0xFEF5, 0xFEF5), (0xFEF7, 0xFEF7), (0xFEF9, 0xFEF9), (0xFEFB, 0xFEFB),
+];
+
+/// `Bidi_Mirroring_Glyph` (`UCharacter.getMirror`): each pair is two
+/// neighbouring characters that mirror each other.
+const MIRRORED: &str = "\
+        ()<>[]{}«»༺༻༼༽᚛᚜‹›⁅⁆⁽⁾₍₎∈∋∉∌∊∍∕⧵∟⯾∠⦣∡⦛∢⦠∤⫮∼∽≃⋍≅≌≒≓\
+        ≔≕≤≥≦≧≨≩≪≫≮≯≰≱≲≳≴≵≶≷≸≹≺≻≼≽≾≿⊀⊁⊂⊃⊄⊅⊆⊇⊈⊉⊊⊋⊏⊐⊑⊒⊘⦸⊢⊣⊦⫞\
+        ⊨⫤⊩⫣⊫⫥⊰⊱⊲⊳⊴⊵⊶⊷⊸⟜⋉⋊⋋⋌⋐⋑⋖⋗⋘⋙⋚⋛⋜⋝⋞⋟⋠⋡⋢⋣⋤⋥⋦⋧⋨⋩⋪⋫⋬⋭⋰⋱⋲⋺\
+        ⋳⋻⋴⋼⋶⋽⋷⋾⌈⌉⌊⌋〈〉❨❩❪❫❬❭❮❯❰❱❲❳❴❵⟃⟄⟅⟆⟈⟉⟋⟍⟕⟖⟝⟞⟢⟣⟤⟥⟦⟧⟨⟩⟪⟫\
+        ⟬⟭⟮⟯⦃⦄⦅⦆⦇⦈⦉⦊⦋⦌⦍⦐⦎⦏⦑⦒⦓⦔⦕⦖⦗⦘⦤⦥⦨⦩⦪⦫⦬⦭⦮⦯⧀⧁⧄⧅⧏⧐⧑⧒⧔⧕⧘⧙⧚⧛\
+        ⧨⧩⧸⧹⧼⧽⨫⨬⨭⨮⨴⨵⨼⨽⩤⩥⩹⩺⩻⩼⩽⩾⩿⪀⪁⪂⪃⪄⪅⪆⪇⪈⪉⪊⪋⪌⪍⪎⪏⪐⪑⪒⪓⪔⪕⪖⪗⪘⪙⪚\
+        ⪛⪜⪝⪞⪟⪠⪡⪢⪦⪧⪨⪩⪪⪫⪬⪭⪯⪰⪱⪲⪳⪴⪵⪶⪷⪸⪹⪺⪻⪼⪽⪾⪿⫀⫁⫂⫃⫄⫅⫆⫇⫈⫉⫊⫋⫌⫍⫎⫏⫐\
+        ⫑⫒⫓⫔⫕⫖⫬⫭⫷⫸⫹⫺⸂⸃⸄⸅⸉⸊⸌⸍⸜⸝⸠⸡⸢⸣⸤⸥⸦⸧⸨⸩⹕⹖⹗⹘⹙⹚⹛⹜〈〉《》「」『』【】\
+        〔〕〖〗〘〙〚〛﹙﹚﹛﹜﹝﹞﹤﹥（）＜＞［］｛｝｟｠｢｣";
+
+fn join(c: char) -> Join {
+    let c = c as u32;
+    JOINS
+        .iter()
+        .find(|&&(from, to, _)| (from..=to).contains(&c))
+        .map_or(Join::None, |&(_, _, join)| join)
+}
+
+/// The letter whose joined form `c` is (ICU shapes the forms again), or `c`.
+fn letter_of(c: char) -> char {
+    let c32 = c as u32;
+    if !matches!(c32, 0xFE70..=0xFEFC) {
+        return c;
+    }
+    if (0xFE70..0xFE80).contains(&c32) {
+        // The diacritics' forms pair up from fathatan on.
+        return char::from_u32(0x064B + (c32 - 0xFE70) / 2).unwrap_or(c);
+    }
+    FORMS
+        .iter()
+        .find(|&&(letter, iso)| {
+            let forms = if join(char::from_u32(letter).unwrap_or(c)) == Dual {
+                4
+            } else {
+                2
+            };
+            (iso..iso + forms).contains(&c32)
+        })
+        .and_then(|&(letter, _)| char::from_u32(letter))
+        .unwrap_or(c)
+}
+
+/// `ArabicShaping(LETTERS_SHAPE).shape`: lam followed by an alef (diacritics
+/// may sit between) becomes one ligature, then every letter takes the isolated,
+/// final, initial or medial form its neighbours call for. Diacritics take the
+/// tatweel form between two joined letters. The text can only get shorter.
+fn shape(text: &[char]) -> Vec<char> {
+    let letters: Vec<char> = text.iter().map(|&c| letter_of(c)).collect();
+    let mut chars = Vec::with_capacity(letters.len());
+    let mut i = 0;
+    while i < letters.len() {
+        if letters[i] == '\u{644}' {
+            let mut at = i + 1;
+            while letters.get(at).is_some_and(|&c| join(c) == Mark) {
+                at += 1;
+            }
+            let alef = letters.get(at).and_then(|&c| {
+                ['\u{622}', '\u{623}', '\u{625}', '\u{627}']
+                    .iter()
+                    .position(|&a| a == c)
+            });
+            if let Some(alef) = alef {
+                chars.push(char::from_u32(0xFEF5 + 2 * alef as u32).unwrap_or('\u{644}'));
+                chars.extend_from_slice(&letters[i + 1..at]);
+                i = at + 1;
+                continue;
+            }
+        }
+        chars.push(letters[i]);
+        i += 1;
+    }
+    // Whether the nearest letter before joins the next one, and the joins of
+    // the nearest letter after.
+    let mut joins_next = false;
+    let mut out = Vec::with_capacity(chars.len());
+    for (i, &c) in chars.iter().enumerate() {
+        let next_joins = chars[i + 1..]
+            .iter()
+            .map(|&n| join(n))
+            .find(|&j| j != Mark)
+            .is_some_and(|j| j != Join::None);
+        let kind = join(c);
+        let shaped = match kind {
+            Join::None => {
+                joins_next = false;
+                c
+            }
+            Mark => match c as u32 {
+                m @ 0x064B..=0x0652 => {
+                    let iso = 0xFE70 + 2 * (m - 0x064B);
+                    let tatweel = joins_next && next_joins && !matches!(m, 0x064C | 0x064D);
+                    char::from_u32(iso + u32::from(tatweel)).unwrap_or(c)
+                }
+                _ => c,
+            },
+            Right | Dual => {
+                let to_next = kind == Dual && next_joins;
+                let form = match (joins_next, to_next) {
+                    (false, false) => 0,
+                    (true, false) => 1,
+                    (false, true) => 2,
+                    (true, true) => 3,
+                };
+                joins_next = kind == Dual;
+                FORMS
+                    .binary_search_by_key(&(c as u32), |&(letter, _)| letter)
+                    .ok()
+                    .and_then(|at| char::from_u32(FORMS[at].1 + form))
+                    .unwrap_or(c)
+            }
+        };
+        out.push(shaped);
+    }
+    out
+}
+
+/// `UCharacter.getMirror`.
+fn mirror(c: char) -> char {
+    if bidi_class(c) != BidiClass::ON {
+        return c;
+    }
+    let mut pairs = MIRRORED.chars();
+    while let (Some(a), Some(b)) = (pairs.next(), pairs.next()) {
+        if c == a {
+            return b;
+        }
+        if c == b {
+            return a;
+        }
+    }
+    c
+}
+
+/// Whether a character can change anything: right-to-left letters and numbers,
+/// the explicit direction controls and the diacritics that shaping turns into
+/// letters. Without any, left-to-right text keeps its order.
+fn directional(c: char) -> bool {
+    c as u32 >= 0x0590
+        && (matches!(c as u32, 0x064B..=0x0652)
+            || matches!(
+                bidi_class(c),
+                BidiClass::R
+                    | BidiClass::AL
+                    | BidiClass::AN
+                    | BidiClass::LRE
+                    | BidiClass::RLE
+                    | BidiClass::LRO
+                    | BidiClass::RLO
+                    | BidiClass::PDF
+                    | BidiClass::LRI
+                    | BidiClass::RLI
+                    | BidiClass::FSI
+                    | BidiClass::PDI
+            ))
+}
+
+/// Whether `chars` keep their order and shapes: left-to-right text without
+/// anything directional, in a language that reads left to right by default.
+fn unchanged(mut chars: impl Iterator<Item = char>, default_rtl: bool) -> bool {
+    !default_rtl && !chars.any(directional)
+}
+
+/// `FormattedBidiReorder.reorder`: `chars` shaped, in visual order, with each
+/// character's position in the shaped text. A character's style is the one at
+/// its position in the shaped text, as `SubStringSource` takes it (the text
+/// shrinks at a lam-alef ligature).
+fn reorder(chars: &[char], default_rtl: bool) -> Vec<(char, usize)> {
+    let shaped = shape(chars);
+    let plain: String = shaped.iter().collect();
+    // DEFAULT_RTL only changes text without a strong character.
+    let level =
+        (default_rtl && get_base_direction(plain.as_str()) == Direction::Mixed).then(Level::rtl);
+    let info = ParagraphBidiInfo::new(&plain, level);
+    let levels = info.reordered_levels_per_char(0..plain.len());
+    ParagraphBidiInfo::reorder_visual(&levels)
+        .into_iter()
+        .map(|i| {
+            let c = if levels[i].is_rtl() {
+                mirror(shaped[i])
+            } else {
+                shaped[i]
+            };
+            (c, i)
+        })
+        .collect()
+}
+
+/// `Language.getVisualOrder` of a text (its `§` codes already resolved), for
+/// the current language's direction.
+pub fn visual(text: &Text) -> Cow<'_, Text> {
+    let default_rtl = crate::lang::bidirectional();
+    if unchanged(text.chars().map(|(c, _)| c), default_rtl) {
+        return Cow::Borrowed(text);
+    }
+    let chars: Vec<char> = text.chars().map(|(c, _)| c).collect();
+    let styles: Vec<_> = text.chars().map(|(_, style)| style).collect();
+    let mut out = Text::default();
+    for (c, at) in reorder(&chars, default_rtl) {
+        match out.spans.last_mut() {
+            Some(span) if span.style == *styles[at] => span.text.push(c),
+            _ => out.spans.push(Span {
+                text: c.to_string(),
+                style: styles[at].clone(),
+            }),
+        }
+    }
+    Cow::Owned(out)
+}
+
+/// The same for a plain string.
+pub fn visual_str(s: &str) -> Cow<'_, str> {
+    let default_rtl = crate::lang::bidirectional();
+    if unchanged(s.chars(), default_rtl) {
+        return Cow::Borrowed(s);
+    }
+    let chars: Vec<char> = s.chars().collect();
+    Cow::Owned(
+        reorder(&chars, default_rtl)
+            .into_iter()
+            .map(|(c, _)| c)
+            .collect(),
+    )
+}

crates/horizon-client-render/src/biome.rs

@@ -1,7 +1,7 @@
 //! Biome colours from the pinned biome definitions and colormaps
 //! (`Biome.getGrassColor`/`getFoliageColor`/..., `BlockTintSources`).
 use crate::Result;
-use horizon_core::{noise::SimplexNoise, random::LegacyRandom};
+use horizon_core::{noise::SimplexNoise, position::BlockPos, random::LegacyRandom};
 use serde_json::Value;
 use std::{collections::HashMap, fs, path::Path};
 
@@ -20,12 +20,68 @@ pub struct SpawnEntry {
     /// A `ConstantInt` count (sampling draws nothing).
     pub constant: bool,
 }
+/// A `natural_mob_spawns` / `spawn_overrides` entry list.
+pub fn parse_entries(list: &Value) -> Vec<SpawnEntry> {
+    list.as_array()
+        .into_iter()
+        .flatten()
+        .filter_map(|e| {
+            let count = &e["count"];
+            let (min, max, constant) = match count {
+                Value::Number(n) => {
+                    let n = n.as_u64().unwrap_or(1) as u32;
+                    (n, n, true)
+                }
+                c if c["type"].as_str() == Some("minecraft:constant") => {
+                    let n = c["value"].as_u64().unwrap_or(1) as u32;
+                    (n, n, true)
+                }
+                c => (
+                    c["min_inclusive"].as_u64().unwrap_or(1) as u32,
+                    c["max_inclusive"].as_u64().unwrap_or(1) as u32,
+                    false,
+                ),
+            };
+            Some(SpawnEntry {
+                entity: e["type"].as_str()?.to_owned(),
+                weight: e["weight"].as_u64().unwrap_or(1) as u32,
+                min,
+                max,
+                constant,
+            })
+        })
+        .collect()
+}
+/// `MobSpawnSettings.MobSpawnCost`.
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub struct SpawnCost {
+    pub energy_budget: f64,
+    pub charge: f64,
+}
+/// The `spawn_costs` of a `natural_mob_spawns` value.
+pub fn parse_costs(costs: &Value) -> HashMap<String, SpawnCost> {
+    costs
+        .as_object()
+        .into_iter()
+        .flatten()
+        .map(|(k, c)| {
+            (
+                k.clone(),
+                SpawnCost {
+                    energy_budget: c["energy_budget"].as_f64().unwrap_or(0.0),
+                    charge: c["charge"].as_f64().unwrap_or(0.0),
+                },
+            )
+        })
+        .collect()
+}
+
 #[derive(Clone, Debug)]
 pub struct BiomeInfo {
     /// `natural_mob_spawns` by category (creature, monster, ...).
     pub spawns: HashMap<String, Vec<SpawnEntry>>,
     /// `natural_mob_spawns` spawn costs by entity type.
-    pub spawn_costs: HashMap<String, crate::mobs::spawn_selection::SpawnCost>,
+    pub spawn_costs: HashMap<String, SpawnCost>,
     /// The `gameplay/creature_world_gen_spawn_probability` attribute.
     pub creature_probability: f32,
     /// The `gameplay/increased_fire_burnout` attribute (jungles, swamps, peaks,
@@ -33,6 +89,8 @@ pub struct BiomeInfo {
     pub increased_fire_burnout: bool,
     pub name: String,
     pub temperature: f32,
+    /// `temperature_modifier: frozen` (the frozen oceans).
+    pub frozen: bool,
     pub downfall: f32,
     pub precipitation: bool,
     pub grass: u32,
@@ -45,6 +103,33 @@ pub struct BiomeInfo {
     pub fog: Option<u32>,
     pub water_fog: u32,
 }
+impl BiomeInfo {
+    /// `Biome.getHeightAdjustedTemperature`: the frozen modifier, then cooler
+    /// with height above `sea_level + 17`.
+    pub fn temperature_at(&self, pos: BlockPos, sea_level: i32) -> f32 {
+        use horizon_world::worldgen::biome_temperature::{
+            BiomeTemperatureSettings, TemperatureModifier,
+        };
+        BiomeTemperatureSettings {
+            base_temperature: self.temperature,
+            modifier: if self.frozen {
+                TemperatureModifier::Frozen
+            } else {
+                TemperatureModifier::None
+            },
+            has_precipitation: self.precipitation,
+            downfall: self.downfall,
+        }
+        .height_adjusted(pos, sea_level)
+    }
+    /// `Biome.getPrecipitationAt` in the Overworld (sea level 63): None
+    /// without precipitation, else whether it falls as snow
+    /// (`getHeightAdjustedTemperature` below 0.15).
+    pub fn snows_at(&self, x: i32, y: i32, z: i32) -> Option<bool> {
+        self.precipitation
+            .then(|| self.temperature_at(BlockPos::new(x, y, z), 63) < 0.15)
+    }
+}
 pub struct Biomes {
     pub list: Vec<BiomeInfo>,
     pub index: HashMap<String, u16>,
@@ -121,12 +206,12 @@ impl Biomes {
             };
             let categories = &natural["spawns_by_category"];
             for (category, entries) in categories.as_object().into_iter().flatten() {
-                let list = crate::mobs::spawn_selection::parse_entries(entries);
+                let list = parse_entries(entries);
                 spawns.insert(category.clone(), list);
             }
             list.push(BiomeInfo {
                 spawns,
-                spawn_costs: crate::mobs::spawn_selection::parse_costs(&natural["spawn_costs"]),
+                spawn_costs: parse_costs(&natural["spawn_costs"]),
                 creature_probability:
                     attributes["minecraft:gameplay/creature_world_gen_spawn_probability"]
                         .as_f64()
@@ -135,6 +220,7 @@ impl Biomes {
                     .as_bool()
                     .unwrap_or(false),
                 temperature,
+                frozen: v["temperature_modifier"].as_str() == Some("frozen"),
                 downfall,
                 precipitation: v["has_precipitation"].as_bool().unwrap_or(true),
                 grass: color(&effects["grass_color"])

crates/horizon-client-render/src/block_entities.rs

@@ -23,9 +23,10 @@
 //! Which states tick is a table by state id, built by the game from the block
 //! registry; whether a slot is made is decided when the slot is promoted at
 //! the start of the next tick, from the block state then.
-use crate::containers::BlockEntity;
+use crate::chunk::block_entity::BlockEntity;
 use crate::fast_hash::{FxHashMap, FxHashSet};
 use std::collections::HashMap;
+use std::sync::Arc;
 
 pub type Pos = (i32, i32, i32);
 
@@ -46,7 +47,7 @@ pub enum Ticking {
 pub struct BlockEntities {
     map: HashMap<Pos, BlockEntity>,
     /// `Level.blockEntityTickers`: positions and the slot each was given.
-    tickers: Vec<(Pos, u32)>,
+    tickers: Arc<Vec<(Pos, u32)>>,
     /// `LevelChunk.tickersInLevel`: the live slot of each ticking position.
     live: FxHashMap<Pos, u32>,
     /// Positions that may need a slot, in the order vanilla would have made
@@ -233,7 +234,7 @@ impl BlockEntities {
     }
     pub fn clear(&mut self) {
         self.map.clear();
-        self.tickers.clear();
+        self.tickers = Arc::default();
         self.live.clear();
         self.added.clear();
         self.pending.clear();
@@ -274,7 +275,7 @@ impl BlockEntities {
     /// and freed ones leave it. `state` reads the block state at a position.
     /// Returns the slots to tick, in order; check each with `is_live` before
     /// ticking it, as the ticks before it can free it.
-    pub fn tickers(&mut self, state: impl Fn(Pos) -> u32) -> Vec<(Pos, u32)> {
+    pub fn tickers(&mut self, state: impl Fn(Pos) -> u32) -> Arc<Vec<(Pos, u32)>> {
         for (pos, token) in std::mem::take(&mut self.added) {
             if self.pending.get(&pos) != Some(&token) {
                 continue;
@@ -288,21 +289,21 @@ impl BlockEntities {
             }
             let slot = self.next();
             self.live.insert(pos, slot);
-            self.tickers.push((pos, slot));
+            Arc::make_mut(&mut self.tickers).push((pos, slot));
         }
         if !std::mem::take(&mut self.freed) && self.out.is_empty() {
-            return self.tickers.clone();
+            return Arc::clone(&self.tickers);
         }
         self.out.clear();
         let (live, map) = (&mut self.live, &self.map);
-        self.tickers.retain(|(p, slot)| {
+        Arc::make_mut(&mut self.tickers).retain(|(p, slot)| {
             let mine = live.get(p) == Some(slot);
             if mine && !map.contains_key(p) {
                 live.remove(p);
             }
             mine && map.contains_key(p)
         });
-        self.tickers.clone()
+        Arc::clone(&self.tickers)
     }
     /// Whether a slot from `tickers` still ticks.
     pub fn is_live(&self, (pos, slot): (Pos, u32)) -> bool {
@@ -329,8 +330,8 @@ mod tests {
     }
     fn order(b: &mut BlockEntities, states: &HashMap<Pos, u32>) -> Vec<Pos> {
         b.tickers(|p| states.get(&p).copied().unwrap_or(0))
-            .into_iter()
-            .map(|(p, _)| p)
+            .iter()
+            .map(|(p, _)| *p)
             .collect()
     }
 

crates/horizon-client-render/src/block_entity_anim.rs

@@ -435,7 +435,8 @@ pub struct BellTick {
     pub ended: Option<(Vec<([f64; 3], i32)>, Vec<u64>)>,
 }
 
-fn closer_to_center_than(pos: [i32; 3], p: [f64; 3], distance: f64) -> bool {
+/// `Vec3i.closerToCenterThan`: `p` is within `distance` of the block's centre.
+pub fn closer_to_center_than(pos: [i32; 3], p: [f64; 3], distance: f64) -> bool {
     let dx = f64::from(pos[0]) + 0.5 - p[0];
     let dy = f64::from(pos[1]) + 0.5 - p[1];
     let dz = f64::from(pos[2]) + 0.5 - p[2];

crates/horizon-client-render/src/block_entity_render.rs

@@ -5,7 +5,11 @@
 //! (`entity-models.json`); transforms, animation and textures follow each
 //! vanilla renderer. Faces are lit like the `entity` shader: the lightmap at
 //! the block plus `minecraft_mix_light` with the level's two diffuse lights.
-use crate::{hud::Rect, mesher::Vertex, world::World};
+use crate::{
+    hud::Rect,
+    mesher::{CULL_BACK, Vertex},
+    world::World,
+};
 use glam::{DVec3, Mat4, Quat, Vec3};
 use horizon_core::geometry::{
     Direction,
@@ -93,6 +97,16 @@ pub fn diffuse(normal: Vec3, lights: (Vec3, Vec3)) -> f32 {
 pub fn vertex_light(packed: u8) -> u32 {
     (u32::from(packed >> 4) * 16) | ((u32::from(packed & 15) * 16) << 8)
 }
+/// `ChestRenderer.xmasTextures`: `SpecialDates.isExtendedChristmas` (24 to 26
+/// December in the local time zone), read once when the renderer is created.
+fn extended_christmas() -> bool {
+    use chrono::Datelike;
+    static XMAS: std::sync::OnceLock<bool> = std::sync::OnceLock::new();
+    *XMAS.get_or_init(|| {
+        let now = chrono::Local::now();
+        now.month() == 12 && (24..=26).contains(&now.day())
+    })
+}
 fn pack_color(rgb: u32, alpha: u32, brightness: f32) -> u32 {
     let c = |shift: u32| (((rgb >> shift) & 255) as f32 * brightness) as u32;
     alpha << 24 | c(0) << 16 | c(8) << 8 | c(16)
@@ -149,6 +163,8 @@ pub fn draw_part(
                 layer: 0,
                 color,
                 light,
+
+                glint_uv: [0.0, 0.0],
             });
         }
     }
@@ -581,6 +597,18 @@ fn first_line(line: &str, max_width: f32, advance: &dyn Fn(char) -> f32) -> Stri
     line.to_owned()
 }
 
+/// `AbstractSignRenderer.isOutlineVisible`: the camera within 16 blocks of
+/// the sign's centre.
+fn sign_text_near(pos: [i32; 3], camera: DVec3) -> bool {
+    DVec3::new(
+        f64::from(pos[0]) + 0.5,
+        f64::from(pos[1]) + 0.5,
+        f64::from(pos[2]) + 0.5,
+    )
+    .distance_squared(camera)
+        < 256.0
+}
+
 /// `AbstractSignRenderer.submitSignText`: four centred lines, glowing text
 /// full-bright with an 8x outline in the dark colour.
 fn sign_text_calls(
@@ -610,7 +638,9 @@ fn sign_text_calls(
         .iter()
         .enumerate()
         .map(|(i, line)| {
+            // The line that fits, in the order it is drawn (getVisualOrder).
             let shown = first_line(line, data.max_line_width(), &advance);
+            let shown = crate::bidi::visual_str(&shown).into_owned();
             TextCall {
                 matrix: m,
                 x: -((width(&shown) as i32) / 2) as f32,
@@ -624,10 +654,20 @@ fn sign_text_calls(
         .collect()
 }
 
+/// How far the text of an outlined call sits in front of its outline, in
+/// text units (`Font.DisplayMode.POLYGON_OFFSET`, see `draw_text`).
+const TEXT_OVER_OUTLINE: f32 = 0.05;
+
 /// Draws a text call with the font atlas: 8x8 glyph cells, the outline as
 /// eight one-pixel offsets under the text.
+///
+/// `TextFeatureRenderer.renderText` draws the outline glyphs NORMAL and the
+/// text over them POLYGON_OFFSET, so the coplanar text always wins the depth
+/// test. Here both share one mesh, so the text is lifted a hair towards the
+/// reader instead (a twentieth of a font pixel, invisible) rather than
+/// z-fighting with the outline under it.
 fn draw_text(scene: &Scene, call: &TextCall, out: &mut Vec<Vertex>) {
-    let mut emit = |dx: f32, dy: f32, argb: u32| {
+    let mut emit = |dx: f32, dy: f32, z: f32, argb: u32| {
         let mut x = call.x + dx;
         let y0 = call.y + dy;
         for ch in call.text.chars() {
@@ -642,12 +682,14 @@ fn draw_text(scene: &Scene, call: &TextCall, out: &mut Vec<Vertex>) {
                         normal: [0; 4],
                         pos: call
                             .matrix
-                            .transform_point3(Vec3::new(cx, cy, 0.0))
+                            .transform_point3(Vec3::new(cx, cy, z))
                             .to_array(),
                         uv,
                         layer: 0,
                         color: c,
                         light: call.light,
+
+                        glint_uv: [0.0, 0.0],
                     });
                 }
             }
@@ -665,10 +707,15 @@ fn draw_text(scene: &Scene, call: &TextCall, out: &mut Vec<Vertex>) {
             (0.0, 1.0),
             (1.0, 1.0),
         ] {
-            emit(dx, dy, call.outline);
+            emit(dx, dy, 0.0, call.outline);
         }
     }
-    emit(0.0, 0.0, call.color);
+    let z = if call.outline != 0 {
+        TEXT_OVER_OUTLINE
+    } else {
+        0.0
+    };
+    emit(0.0, 0.0, z, call.color);
 }
 
 /// Block-entity fields the level ticks, at one position (vanilla's own field
@@ -734,9 +781,12 @@ pub struct Scene<'a> {
     /// The skin sprite a `player_head` shows at a position (`SkullBlockRenderer`
     /// profile → skin): a downloaded `skins/<sha1>` slot or the profile's
     /// `DefaultPlayerSkin` fallback; None keeps `SKIN_BY_TYPE` (`DefaultPlayerSkin.getDefaultTexture`, slim steve).
-    pub skull: &'a dyn Fn([i32; 3]) -> Option<&'a str>,
+    pub skull: &'a dyn Fn([i32; 3]) -> Option<String>,
     /// Font glyph cell (none for blank glyphs such as the space) and advance.
     pub glyph: &'a dyn Fn(char) -> (Option<Rect>, f32),
+    /// Changes whenever `glyph` may answer differently (`Font::epoch`): sign
+    /// text laid out under another value is laid out again.
+    pub glyphs: u64,
 }
 
 pub struct BlockEntityRenderer {
@@ -748,7 +798,30 @@ pub struct BlockEntityRenderer {
     pot_patterns: HashMap<String, String>,
     /// `Block.shouldRenderFace` for End gateway faces (its occlusion pair cache needs a lock).
     visibility: Option<Mutex<FaceVisibility>>,
+    sign_texts: Mutex<SignTexts>,
 }
+/// Laid-out sign text by position. `AbstractSignRenderer` lays the text out
+/// again each frame, glyph by glyph; its vertices only change with what is
+/// in the key, so they are kept relative to the block and moved to the camera.
+#[derive(Default)]
+struct SignTexts {
+    signs: crate::fast_hash::FxHashMap<[i32; 3], SignTextEntry>,
+    /// Game time of the last sweep of signs out of view.
+    swept: i64,
+}
+struct SignTextEntry {
+    state: u32,
+    data: crate::signs::SignData,
+    packed: u8,
+    /// Within the glowing text outline's distance (only kept for glowing text).
+    near: bool,
+    glyphs: u64,
+    /// Game time it was last drawn.
+    used: i64,
+    vertices: Vec<Vertex>,
+}
+/// Game ticks a sign's text is kept after it was last drawn.
+const SIGN_TEXT_KEEP: i64 = 100;
 const MODELS: [(&str, &str); 27] = [
     ("chest", "minecraft:chest#main"),
     ("double_chest_left", "minecraft:double_chest_left#main"),
@@ -878,6 +951,7 @@ impl BlockEntityRenderer {
             closed_chests,
             pot_patterns: HashMap::new(),
             visibility: None,
+            sign_texts: Mutex::default(),
         }
     }
     fn kind(&self, state: u32) -> &Kind {
@@ -912,11 +986,81 @@ impl BlockEntityRenderer {
             let origin = (DVec3::new(f64::from(pos[0]), f64::from(pos[1]), f64::from(pos[2]))
                 - scene.camera)
                 .as_vec3();
-            let base = Mat4::from_translation(origin);
             let packed = scene.world.light(pos[0], pos[1], pos[2]);
+            if matches!(kind, Kind::Sign { .. }) && scene.texts.is_none() {
+                self.sign_text(scene, *pos, *state, origin, packed, out);
+                continue;
+            }
+            let base = Mat4::from_translation(origin);
             self.render_one(scene, *pos, kind, base, packed, lights, false, true, out);
         }
     }
+    /// A sign's text from the cache, laid out again when its data, light,
+    /// state, outline or font changed.
+    fn sign_text(
+        &self,
+        scene: &Scene,
+        pos: [i32; 3],
+        state: u32,
+        origin: Vec3,
+        packed: u8,
+        out: &mut Vec<Vertex>,
+    ) {
+        let Some(data) = (scene.sign)(pos) else {
+            return;
+        };
+        let near = (data.front.glowing || data.back.glowing) && sign_text_near(pos, scene.camera);
+        let Ok(mut cache) = self.sign_texts.lock() else {
+            return;
+        };
+        let now = scene.game_time;
+        if (now - cache.swept).abs() >= SIGN_TEXT_KEEP {
+            cache.swept = now;
+            cache
+                .signs
+                .retain(|_, e| (now - SIGN_TEXT_KEEP..=now).contains(&e.used));
+        }
+        let glyphs = scene.glyphs;
+        let signs = &mut cache.signs;
+        if !signs.get(&pos).is_some_and(|e| {
+            (e.state, e.packed, e.near, e.glyphs) == (state, packed, near, glyphs)
+                && e.data == *data
+        }) {
+            let mut vertices = signs.remove(&pos).map_or_else(Vec::new, |e| e.vertices);
+            vertices.clear();
+            self.render_one(
+                scene,
+                pos,
+                self.kind(state),
+                Mat4::IDENTITY,
+                packed,
+                diffuse_lights(scene.nether),
+                false,
+                true,
+                &mut vertices,
+            );
+            signs.insert(
+                pos,
+                SignTextEntry {
+                    state,
+                    data: data.clone(),
+                    packed,
+                    near,
+                    glyphs,
+                    used: now,
+                    vertices,
+                },
+            );
+        }
+        let Some(entry) = signs.get_mut(&pos) else {
+            return;
+        };
+        entry.used = now;
+        out.extend(entry.vertices.iter().map(|v| Vertex {
+            pos: (Vec3::from_array(v.pos) + origin).to_array(),
+            ..*v
+        }));
+    }
     /// One block entity at `pos` drawn under `base` with the given packed light
     /// (the parity fixture's entry point).
     pub fn render_block(
@@ -932,6 +1076,30 @@ impl BlockEntityRenderer {
         let lights = diffuse_lights(scene.nether);
         self.render_one(scene, pos, kind, base, packed, lights, false, false, out);
     }
+    /// `TheEndGatewayBlockEntity.shouldRenderFace` for each face of the gateway
+    /// at `pos`: the faces its portal is drawn on.
+    pub fn gateway_faces(
+        &self,
+        world: &World,
+        state: BlockStateId,
+        pos: [i32; 3],
+    ) -> Vec<Direction> {
+        Direction::ALL
+            .into_iter()
+            .filter(|&d| {
+                let [dx, dy, dz] = d.normal();
+                let neighbor = world.block(pos[0] + dx, pos[1] + dy, pos[2] + dz);
+                self.visibility.as_ref().is_none_or(|v| {
+                    v.lock()
+                        .map(|mut v| {
+                            v.should_render_face(state, neighbor, d, true)
+                                .unwrap_or(true)
+                        })
+                        .unwrap_or(true)
+                })
+            })
+            .collect()
+    }
     /// Whether this block state has a block-entity renderer here.
     pub fn renders(&self, state: u32) -> bool {
         !matches!(self.kind(state), Kind::None)
@@ -1124,13 +1292,7 @@ impl BlockEntityRenderer {
                         m *= Mat4::from_translation(Vec3::new(0.0, 1.0 / 3.0, 0.046_666_667))
                             * Mat4::from_scale(s * 0.010_416_667);
                     }
-                    let near = DVec3::new(
-                        f64::from(pos[0]) + 0.5,
-                        f64::from(pos[1]) + 0.5,
-                        f64::from(pos[2]) + 0.5,
-                    )
-                    .distance_squared(scene.camera)
-                        < 256.0;
+                    let near = sign_text_near(pos, scene.camera);
                     let calls = sign_text_calls(scene, data, text, m, packed, near);
                     match scene.texts {
                         Some(sink) => sink.borrow_mut().extend(calls),
@@ -1139,11 +1301,25 @@ impl BlockEntityRenderer {
                 }
             }
             Kind::Chest {
+                block,
                 texture,
                 part,
                 y_rot,
                 ..
             } => {
+                // ChestRenderer.getChestMaterial: normal and trapped chests use the christmas
+                // sprites on 24-26 December. Copper and ender chests keep theirs.
+                let texture = if matches!(block.as_str(), "chest" | "trapped_chest")
+                    && extended_christmas()
+                {
+                    match part {
+                        ChestPart::Single => "entity/chest/christmas",
+                        ChestPart::Left => "entity/chest/christmas_left",
+                        ChestPart::Right => "entity/chest/christmas_right",
+                    }
+                } else {
+                    *texture
+                };
                 let model = match part {
                     ChestPart::Single => "chest",
                     ChestPart::Left => "double_chest_left",
@@ -1286,11 +1462,12 @@ impl BlockEntityRenderer {
                 };
                 // SkullBlockRenderer.getRenderType: the profile's skin when it
                 // resolves, `SKIN_BY_TYPE` (steve) otherwise.
-                let texture = if *kind == SkullType::Player {
-                    (scene.skull)(pos).unwrap_or(texture)
+                let skin = if *kind == SkullType::Player {
+                    (scene.skull)(pos)
                 } else {
-                    texture
+                    None
                 };
+                let texture = skin.as_deref().unwrap_or(texture);
                 let (Some(model), Some(paint)) =
                     (self.models.get(model), paint(texture, 0xFFFFFF, packed))
                 else {
@@ -1385,6 +1562,7 @@ impl BlockEntityRenderer {
                         m *= around(Mat4::from_rotation_y(turn * decay), pivot);
                     }
                 }
+                let first = out.len();
                 if let Some(paint) =
                     paint("entity/decorated_pot/decorated_pot_base", 0xFFFFFF, packed)
                 {
@@ -1402,6 +1580,11 @@ impl BlockEntityRenderer {
                         draw_part(part, side, m, &none, paint, out);
                     }
                 }
+                // `DecoratedPotRenderer` submits every part with `entitySolid`, which culls
+                // back faces: the flat `top` and `bottom` planes show one side each.
+                for vertex in &mut out[first..] {
+                    vertex.normal = CULL_BACK;
+                }
             }
             Kind::EndPortal => {
                 // TheEndPortalRenderer.TRANSFORMATION: y from 6/16 to 12/16; only the
@@ -1432,22 +1615,8 @@ impl BlockEntityRenderer {
                         out,
                     );
                 }
-                // AbstractEndPortalRenderer.extractRenderState: TheEndGatewayBlockEntity.shouldRenderFace.
-                let faces: Vec<Direction> = Direction::ALL
-                    .into_iter()
-                    .filter(|&d| {
-                        let [dx, dy, dz] = d.normal();
-                        let neighbor = scene.world.block(pos[0] + dx, pos[1] + dy, pos[2] + dz);
-                        self.visibility.as_ref().is_none_or(|v| {
-                            v.lock()
-                                .map(|mut v| {
-                                    v.should_render_face(BlockStateId(*state), neighbor, d, true)
-                                        .unwrap_or(true)
-                                })
-                                .unwrap_or(true)
-                        })
-                    })
-                    .collect();
+                // AbstractEndPortalRenderer.extractRenderState.
+                let faces = self.gateway_faces(scene.world, BlockStateId(*state), pos);
                 portal_cube(base, &faces, END_GATEWAY_LAYER, out);
             }
             Kind::Conduit => {
@@ -1714,6 +1883,8 @@ impl BeamPart {
                     layer: 6,
                     color,
                     light: self.wrap,
+
+                    glint_uv: [0.0, 0.0],
                 });
             }
         }
@@ -1784,6 +1955,7 @@ fn portal_cube(m: Mat4, faces: &[Direction], layer: u32, out: &mut Vec<Vertex>)
                 layer,
                 color: 0,
                 light: 0,
+                glint_uv: [0.0, 0.0],
             });
         }
     }
@@ -1900,6 +2072,7 @@ mod tests {
             banner: &|_| Vec::new(),
             skull: &|_| None,
             glyph: &|_| (None, 0.0),
+            glyphs: 0,
         };
         // Compare the cached world path with the original model renderer,
         // including atlas replacement, current light and animated fallback.
@@ -2100,6 +2273,191 @@ mod tests {
         assert_eq!(out[2].uv, [0.5, 0.5]);
     }
 
+    /// TextFeatureRenderer.renderText: an outlined call's text is drawn over
+    /// its outline (Font.DisplayMode.POLYGON_OFFSET), never level with it,
+    /// and plain text stays on the sign's plane.
+    #[test]
+    fn outlined_sign_text_sits_in_front_of_its_outline() {
+        let world = World::new(BlockStateId(0), 1);
+        let sprites = HashMap::new();
+        let glyph = |_: char| {
+            let rect = Rect {
+                u0: 0.0,
+                v0: 0.0,
+                u1: 0.0625,
+                v1: 0.0625,
+                w: 8,
+                h: 8,
+            };
+            (Some(rect), 6.0)
+        };
+        let scene = Scene {
+            camera: DVec3::ZERO,
+            orientation: Quat::IDENTITY,
+            anim: &|_| BlockAnim::default(),
+            texts: None,
+            partial: 0.0,
+            game_time: 0,
+            max_y: 320,
+            world: &world,
+            sprites: &sprites,
+            nether: false,
+            lid: &|_| 0.0,
+            sign: &|_| None,
+            banner: &|_| Vec::new(),
+            skull: &|_| None,
+            glyph: &glyph,
+            glyphs: 0,
+        };
+        let mut call = TextCall {
+            matrix: Mat4::IDENTITY,
+            x: 0.0,
+            y: 0.0,
+            text: "Hi".into(),
+            color: 0xFFFF_FF00,
+            outline: 0xFF33_3300,
+            light: 240 | 240 << 8,
+        };
+        let mut out = Vec::new();
+        draw_text(&scene, &call, &mut out);
+        // Eight outline copies, then the text, four corners a glyph.
+        assert_eq!(out.len(), 9 * 2 * 4);
+        let (outline, text) = out.split_at(8 * 2 * 4);
+        let front = outline.iter().map(|v| v.pos[2]).fold(f32::MIN, f32::max);
+        assert!(
+            text.iter().all(|v| v.pos[2] > front),
+            "text z {:?} not in front of the outline at {front}",
+            text.iter().map(|v| v.pos[2]).collect::<Vec<_>>()
+        );
+        call.outline = 0;
+        out.clear();
+        draw_text(&scene, &call, &mut out);
+        assert_eq!(out.len(), 2 * 4);
+        assert!(out.iter().all(|v| v.pos[2] == 0.0));
+    }
+
+    #[test]
+    fn cached_sign_text_matches_and_follows_changes() {
+        let renderer = BlockEntityRenderer {
+            models: HashMap::new(),
+            kinds: vec![
+                Kind::Sign {
+                    hanging: false,
+                    wall: false,
+                    angle: 180.0,
+                },
+                Kind::Sign {
+                    hanging: true,
+                    wall: true,
+                    angle: 90.0,
+                },
+            ],
+            closed_chests: Default::default(),
+            pot_patterns: HashMap::new(),
+            visibility: None,
+            sign_texts: Mutex::default(),
+        };
+        let world = World::new(BlockStateId(0), 1);
+        let sprites = HashMap::new();
+        let text = |line: &str, glowing| crate::signs::SignText {
+            lines: [line.into(), "two".into(), String::new(), "four".into()],
+            color: 3,
+            glowing,
+        };
+        let first_text = crate::signs::SignData {
+            front: text("one", false),
+            ..Default::default()
+        };
+        let changed = crate::signs::SignData {
+            front: text("changed", false),
+            ..Default::default()
+        };
+        let glowing = crate::signs::SignData {
+            back: text("glow", true),
+            ..changed.clone()
+        };
+        let wide = std::cell::Cell::new(6.0);
+        let glyph = |c: char| {
+            let u = f32::from(c as u8 % 16) / 16.0;
+            let rect = Rect {
+                u0: u,
+                v0: 0.0,
+                u1: u + 0.0625,
+                v1: 0.0625,
+                w: 8,
+                h: 8,
+            };
+            ((c != ' ').then_some(rect), wide.get())
+        };
+        let (first_sign, changed_sign, glowing_sign) = (
+            |_| Some(&first_text),
+            |_| Some(&changed),
+            |_| Some(&glowing),
+        );
+        let mut scene = Scene {
+            camera: DVec3::new(3.25, 70.5, -4.75),
+            orientation: Quat::IDENTITY,
+            anim: &|_| BlockAnim::default(),
+            texts: None,
+            partial: 0.0,
+            game_time: 0,
+            max_y: 320,
+            world: &world,
+            sprites: &sprites,
+            nether: false,
+            lid: &|_| 0.0,
+            sign: &first_sign,
+            banner: &|_| Vec::new(),
+            skull: &|_| None,
+            glyph: &glyph,
+            glyphs: 0,
+        };
+        let check = |scene: &Scene, pos: [i32; 3], state: u32| {
+            let mut cached = Vec::new();
+            renderer.render(scene, [(pos, state)].iter(), &mut cached);
+            let corner = DVec3::new(f64::from(pos[0]), f64::from(pos[1]), f64::from(pos[2]));
+            let mut original = Vec::new();
+            renderer.render_one(
+                scene,
+                pos,
+                renderer.kind(state),
+                Mat4::from_translation((corner - scene.camera).as_vec3()),
+                world.light(pos[0], pos[1], pos[2]),
+                diffuse_lights(false),
+                false,
+                true,
+                &mut original,
+            );
+            assert!(!cached.is_empty());
+            assert_eq!(cached.len(), original.len());
+            for (a, b) in cached.iter().zip(&original) {
+                assert!((Vec3::from_array(a.pos) - Vec3::from_array(b.pos)).length() < 1e-5);
+                assert_eq!((a.uv, a.color, a.light), (b.uv, b.color, b.light));
+            }
+            cached.len()
+        };
+        let (pos, other) = ([1, 70, 2], [-3, 64, 9]);
+        let first = check(&scene, pos, 0);
+        // The camera moves: the same text, moved.
+        scene.camera.x += 0.5;
+        check(&scene, pos, 0);
+        // New text, glowing text near and far, another state, other glyphs.
+        scene.sign = &changed_sign;
+        assert_ne!(check(&scene, pos, 0), first);
+        scene.sign = &glowing_sign;
+        check(&scene, pos, 0);
+        scene.camera.z -= 20.0;
+        check(&scene, pos, 0);
+        check(&scene, pos, 1);
+        check(&scene, other, 1);
+        wide.set(5.0);
+        scene.glyphs = 1;
+        check(&scene, pos, 1);
+        // Signs out of view for a while are dropped.
+        scene.game_time = 2 * SIGN_TEXT_KEEP;
+        check(&scene, pos, 0);
+        assert_eq!(renderer.sign_texts.lock().unwrap().signs.len(), 1);
+    }
     #[test]
     fn first_line_wraps_on_bytes_without_splitting_a_char() {
         let advance = |c: char| if c == ' ' { 4.0 } else { 6.0 };
@@ -2108,4 +2466,71 @@ mod tests {
         assert_eq!(first_line("\u{6771}", 3.0, &advance), "\u{6771}");
         assert_eq!(first_line("ab\ncd", 100.0, &advance), "ab");
     }
+    /// `DecoratedPotRenderer` submits every part with `RenderTypes.entitySolid`,
+    /// whose pipeline culls back faces. The pot's `top` and `bottom` are flat
+    /// boxes, so without that cull both sides of each plane are drawn and they
+    /// z-fight: the pot renders wrong.
+    #[test]
+    fn the_decorated_pot_culls_its_back_faces() {
+        let root = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .join("../../.local/horizon-client")
+            .join(horizon_core::VANILLA_VERSION);
+        if !root.join("entity-models.json").exists() {
+            return;
+        }
+        let assets = crate::assets::Assets::load(&root).unwrap();
+        let registry = assets.registry;
+        let renderer = BlockEntityRenderer::load(&root, registry).unwrap();
+        let state = registry.default_state("minecraft:decorated_pot").unwrap();
+        let sprites: HashMap<String, Rect> = [
+            "entity/decorated_pot/decorated_pot_base",
+            "entity/decorated_pot/decorated_pot_side",
+        ]
+        .into_iter()
+        .map(|name| {
+            (
+                name.to_owned(),
+                Rect {
+                    u0: 0.25,
+                    v0: 0.125,
+                    u1: 0.375,
+                    v1: 0.25,
+                    w: 16,
+                    h: 16,
+                },
+            )
+        })
+        .collect();
+        let world = World::new(BlockStateId(0), 1);
+        let scene = Scene {
+            camera: DVec3::ZERO,
+            orientation: Quat::IDENTITY,
+            anim: &|_| BlockAnim::default(),
+            texts: None,
+            partial: 0.5,
+            game_time: 0,
+            max_y: 320,
+            world: &world,
+            sprites: &sprites,
+            nether: false,
+            lid: &|_| 0.0,
+            sign: &|_| None,
+            banner: &|_| Vec::new(),
+            skull: &|_| None,
+            glyph: &|_| (None, 0.0),
+            glyphs: 0,
+        };
+        let mut verts = Vec::new();
+        renderer.render_block(&scene, [0; 3], state.0, Mat4::IDENTITY, 0xff, &mut verts);
+        // Vanilla submits 28 quads for a plain pot, and the cull keeps them all.
+        assert_eq!(
+            verts.len() / 4,
+            28,
+            "the pot submits all of vanilla's quads"
+        );
+        assert!(
+            verts.iter().all(|v| v.normal == CULL_BACK),
+            "entitySolid culls the pot's back faces"
+        );
+    }
 }

crates/horizon-client-render/src/breaking.rs

@@ -49,6 +49,8 @@ pub fn geometry(
                     color: 0xffff_ffff,
                     light: stage_light(stage),
                     normal: [0; 4],
+
+                    glint_uv: [0.0, 0.0],
                 });
             }
         }

crates/horizon-client-render/src/brewing.rs

@@ -2,247 +2,31 @@
 //! in vanilla, ported as tables), data-driven `minecraft:brewing` recipes from
 //! `data/minecraft/recipe/brewing`, potion colours and tooltips, and
 //! `BrewingStandBlockEntity.serverTick`.
+pub use crate::chunk::block_entity::BrewingStand;
 use crate::{
-    containers::Providers,
     items::{ItemStack, Items},
+    providers::Providers,
 };
 use serde_json::Value;
-use std::{collections::HashSet, fs, path::Path, sync::Arc};
+use std::{collections::HashSet, fs, path::Path};
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum Category {
-    Beneficial,
-    Harmful,
-    Neutral,
-}
-/// A `MobEffect`: id (without namespace), colour, category, instantaneous.
-#[derive(Clone, Copy, Debug)]
-pub struct EffectDef {
-    pub id: &'static str,
-    pub color: u32,
-    pub category: Category,
-    pub instant: bool,
-}
-const fn fx(id: &'static str, color: u32, category: Category) -> EffectDef {
-    EffectDef {
-        id,
-        color,
-        category,
-        instant: false,
-    }
-}
-use Category::{Beneficial as B, Harmful as H, Neutral as N};
-/// `MobEffects` in registration order.
-pub const EFFECTS: &[EffectDef] = &[
-    fx("speed", 3402751, B),
-    fx("slowness", 9154528, H),
-    fx("haste", 14270531, B),
-    fx("mining_fatigue", 4866583, H),
-    fx("strength", 16762624, B),
-    EffectDef {
-        id: "instant_health",
-        color: 16262179,
-        category: B,
-        instant: true,
-    },
-    EffectDef {
-        id: "instant_damage",
-        color: 11101546,
-        category: H,
-        instant: true,
-    },
-    fx("jump_boost", 16646020, B),
-    fx("nausea", 5578058, H),
-    fx("regeneration", 13458603, B),
-    fx("resistance", 9520880, B),
-    fx("fire_resistance", 16750848, B),
-    fx("water_breathing", 10017472, B),
-    fx("invisibility", 16185078, B),
-    fx("blindness", 2039587, H),
-    fx("night_vision", 12779366, B),
-    fx("hunger", 5797459, H),
-    fx("weakness", 4738376, H),
-    fx("poison", 8889187, H),
-    fx("wither", 7561558, H),
-    fx("health_boost", 16284963, B),
-    fx("absorption", 2445989, B),
-    EffectDef {
-        id: "saturation",
-        color: 16262179,
-        category: B,
-        instant: true,
-    },
-    fx("glowing", 9740385, N),
-    fx("levitation", 13565951, H),
-    fx("luck", 5882118, B),
-    fx("unluck", 12624973, H),
-    fx("slow_falling", 15978425, B),
-    fx("conduit_power", 1950417, B),
-    fx("dolphins_grace", 8954814, B),
-    fx("bad_omen", 745784, N),
-    fx("hero_of_the_village", 4521796, B),
-    fx("darkness", 2696993, H),
-    fx("trial_omen", 1484454, N),
-    fx("raid_omen", 14565464, N),
-    fx("wind_charged", 12438015, H),
-    fx("weaving", 7891290, H),
-    fx("oozing", 10092451, H),
-    fx("infested", 9214860, H),
-    fx("breath_of_the_nautilus", 65518, B),
-];
-pub fn effect(id: &str) -> Option<&'static EffectDef> {
-    let id = id.trim_start_matches("minecraft:");
-    EFFECTS.iter().find(|e| e.id == id)
-}
-/// A `Potion`: id, name suffix (`item.minecraft.potion.effect.<name>`) and
-/// effects as (effect, duration ticks, amplifier).
-#[derive(Clone, Copy, Debug)]
-pub struct PotionDef {
-    pub id: &'static str,
-    pub name: &'static str,
-    pub effects: &'static [(&'static str, i32, i32)],
-}
-const fn p(
-    id: &'static str,
-    name: &'static str,
-    effects: &'static [(&'static str, i32, i32)],
-) -> PotionDef {
-    PotionDef { id, name, effects }
-}
-/// `Potions` in registration order.
-pub const POTIONS: &[PotionDef] = &[
-    p("water", "water", &[]),
-    p("mundane", "mundane", &[]),
-    p("thick", "thick", &[]),
-    p("awkward", "awkward", &[]),
-    p("night_vision", "night_vision", &[("night_vision", 3600, 0)]),
-    p(
-        "long_night_vision",
-        "night_vision",
-        &[("night_vision", 9600, 0)],
-    ),
-    p("invisibility", "invisibility", &[("invisibility", 3600, 0)]),
-    p(
-        "long_invisibility",
-        "invisibility",
-        &[("invisibility", 9600, 0)],
-    ),
-    p("leaping", "leaping", &[("jump_boost", 3600, 0)]),
-    p("long_leaping", "leaping", &[("jump_boost", 9600, 0)]),
-    p("strong_leaping", "leaping", &[("jump_boost", 1800, 1)]),
-    p(
-        "fire_resistance",
-        "fire_resistance",
-        &[("fire_resistance", 3600, 0)],
-    ),
-    p(
-        "long_fire_resistance",
-        "fire_resistance",
-        &[("fire_resistance", 9600, 0)],
-    ),
-    p("swiftness", "swiftness", &[("speed", 3600, 0)]),
-    p("long_swiftness", "swiftness", &[("speed", 9600, 0)]),
-    p("strong_swiftness", "swiftness", &[("speed", 1800, 1)]),
-    p("slowness", "slowness", &[("slowness", 1800, 0)]),
-    p("long_slowness", "slowness", &[("slowness", 4800, 0)]),
-    p("strong_slowness", "slowness", &[("slowness", 400, 3)]),
-    p(
-        "turtle_master",
-        "turtle_master",
-        &[("slowness", 400, 3), ("resistance", 400, 2)],
-    ),
-    p(
-        "long_turtle_master",
-        "turtle_master",
-        &[("slowness", 800, 3), ("resistance", 800, 2)],
-    ),
-    p(
-        "strong_turtle_master",
-        "turtle_master",
-        &[("slowness", 400, 5), ("resistance", 400, 3)],
-    ),
-    p(
-        "water_breathing",
-        "water_breathing",
-        &[("water_breathing", 3600, 0)],
-    ),
-    p(
-        "long_water_breathing",
-        "water_breathing",
-        &[("water_breathing", 9600, 0)],
-    ),
-    p("healing", "healing", &[("instant_health", 1, 0)]),
-    p("strong_healing", "healing", &[("instant_health", 1, 1)]),
-    p("harming", "harming", &[("instant_damage", 1, 0)]),
-    p("strong_harming", "harming", &[("instant_damage", 1, 1)]),
-    p("poison", "poison", &[("poison", 900, 0)]),
-    p("long_poison", "poison", &[("poison", 1800, 0)]),
-    p("strong_poison", "poison", &[("poison", 432, 1)]),
-    p("regeneration", "regeneration", &[("regeneration", 900, 0)]),
-    p(
-        "long_regeneration",
-        "regeneration",
-        &[("regeneration", 1800, 0)],
-    ),
-    p(
-        "strong_regeneration",
-        "regeneration",
-        &[("regeneration", 450, 1)],
-    ),
-    p("strength", "strength", &[("strength", 3600, 0)]),
-    p("long_strength", "strength", &[("strength", 9600, 0)]),
-    p("strong_strength", "strength", &[("strength", 1800, 1)]),
-    p("weakness", "weakness", &[("weakness", 1800, 0)]),
-    p("long_weakness", "weakness", &[("weakness", 4800, 0)]),
-    p("luck", "luck", &[("luck", 6000, 0)]),
-    p("slow_falling", "slow_falling", &[("slow_falling", 1800, 0)]),
-    p(
-        "long_slow_falling",
-        "slow_falling",
-        &[("slow_falling", 4800, 0)],
-    ),
-    p("wind_charged", "wind_charged", &[("wind_charged", 3600, 0)]),
-    p("weaving", "weaving", &[("weaving", 3600, 0)]),
-    p("oozing", "oozing", &[("oozing", 3600, 0)]),
-    p("infested", "infested", &[("infested", 3600, 0)]),
-];
-pub fn potion(id: &str) -> Option<&'static PotionDef> {
-    let id = id.trim_start_matches("minecraft:");
-    POTIONS.iter().find(|p| p.id == id)
-}
-/// `PotionContents.BASE_POTION_COLOR` (ARGB -13083194) as RGB.
-pub const BASE_POTION_COLOR: u32 = 0x385DC6;
-/// `PotionContents.getColor`: amplifier-weighted mix of visible effect colours.
-pub fn potion_color(id: Option<&str>) -> u32 {
-    let Some(def) = id.and_then(potion) else {
-        return BASE_POTION_COLOR;
-    };
-    let (mut r, mut g, mut b, mut total) = (0u32, 0u32, 0u32, 0u32);
-    for (e, _, amp) in def.effects {
-        let Some(e) = effect(e) else { continue };
-        let w = *amp as u32 + 1;
-        r += w * (e.color >> 16 & 255);
-        g += w * (e.color >> 8 & 255);
-        b += w * (e.color & 255);
-        total += w;
-    }
-    match (
-        r.checked_div(total),
-        g.checked_div(total),
-        b.checked_div(total),
-    ) {
-        (Some(r), Some(g), Some(b)) => (r << 16) | (g << 8) | b,
-        _ => BASE_POTION_COLOR,
-    }
-}
-/// `MobEffectUtil.formatDuration` at 20 TPS: m:ss or h:mm:ss.
+pub use horizon_client_core::potions::{
+    BASE_POTION_COLOR, Category, EFFECTS, EffectDef, POTIONS, PotionDef, effect, namespaced,
+    potion, potion_color,
+};
+/// `MobEffectUtil.formatDuration` at 20 TPS.
 pub fn format_duration(ticks: i32) -> String {
-    let secs = ticks / 20;
+    format_tick_duration(ticks, 20.0)
+}
+/// `StringUtil.formatTickDuration`: mm:ss, or hh:mm:ss from an hour up, every
+/// field two digits.
+pub fn format_tick_duration(ticks: i32, tick_rate: f32) -> String {
+    let secs = (ticks as f32 / tick_rate).floor() as i32;
     let (h, m, s) = (secs / 3600, secs / 60 % 60, secs % 60);
     if h > 0 {
-        format!("{h}:{m:02}:{s:02}")
+        format!("{h:02}:{m:02}:{s:02}")
     } else {
-        format!("{m}:{s:02}")
+        format!("{m:02}:{s:02}")
     }
 }
 /// `item.minecraft.potion.effect.<name>` style translation key for a potion item.
@@ -412,18 +196,6 @@ impl Brewing {
     }
 }
 
-/// `BrewingStandBlockEntity` state. Slots: 0-2 bottles, 3 ingredient, 4 fuel.
-#[derive(Clone, Debug, Default)]
-pub struct BrewingStand {
-    pub items: [Option<ItemStack>; 5],
-    pub brew_time: i32,
-    pub total_brew_time: i32,
-    pub fuel: i32,
-    pub total_fuel: i32,
-    pub speed: f32,
-    pub ingredient: Option<Arc<str>>,
-    pub last_bottles: Option<[bool; 3]>,
-}
 /// What a brewing tick asks the world to do.
 #[derive(Clone, Debug, Default, PartialEq)]
 pub struct BrewTick {
@@ -550,10 +322,14 @@ mod tests {
             potion_name_key("minecraft:splash_potion", Some("minecraft:long_swiftness")),
             "item.minecraft.splash_potion.effect.swiftness"
         );
-        assert_eq!(format_duration(9600), "8:00");
-        assert_eq!(format_duration(450), "0:22");
+        assert_eq!(format_duration(9600), "08:00");
+        assert_eq!(format_duration(450), "00:22");
+        assert_eq!(format_duration(140), "00:07");
+        assert_eq!(format_duration(1800), "01:30");
+        assert_eq!(format_duration(72000), "01:00:00");
+        assert_eq!(format_tick_duration(9600, 40.0), "04:00");
         let t = tooltip(Some("minecraft:strong_poison"), 1.0, &|_| None);
-        assert_eq!(t[0].0, "poison II (0:21)");
+        assert_eq!(t[0].0, "poison II (00:21)");
         assert_eq!(POTIONS.len(), 46);
     }
 
@@ -610,4 +386,23 @@ mod tests {
         stand.tick(&brewing, &items, &providers);
         assert_eq!(stand.brew_time, 0);
     }
+
+    /// #3312: `PotionContents.getPotionDescription` names the effects with
+    /// translatable components, so a Russian game reads them from ru_ru.json
+    /// (the prepared one; skipped without it), as the tooltip's other lines.
+    #[test]
+    fn effect_lines_read_the_selected_language() {
+        let root = std::path::PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+            .join("../../.local/horizon-client")
+            .join(horizon_core::VANILLA_VERSION);
+        if !root.join("assets/minecraft/lang/ru_ru.json").exists() {
+            return;
+        }
+        let ru = crate::lang::Language::load(&[&root], "ru_ru");
+        let translate = |key: &str| ru.get(key).map(str::to_owned);
+        let lines = tooltip(Some("minecraft:turtle_master"), 0.125, &translate);
+        assert_eq!(lines.len(), 2);
+        assert!(lines[0].0.starts_with("Замедление IV ("), "{lines:?}");
+        assert!(lines[1].0.starts_with("Сопротивление III ("), "{lines:?}");
+    }
 }

crates/horizon-client-render/src/camera.rs

@@ -653,18 +653,57 @@ pub fn modify_fov_based_on_death_or_fluid(
     fov
 }
 
-/// `ClientAvatarState`: the walked distance and view bob of a player.
+/// `ClientAvatarState`: the walked distance, view bob and cloak of a player.
 #[derive(Clone, Copy, Debug, Default, PartialEq)]
 pub struct AvatarBob {
     pub walk_dist: f32,
     pub walk_dist_o: f32,
     pub bob: f32,
     pub bob_o: f32,
+    /// `xCloak`, `yCloak`, `zCloak`: a point trailing the player, which the cape leans from.
+    pub cloak: [f64; 3],
+    pub cloak_o: [f64; 3],
 }
 impl AvatarBob {
-    /// `ClientAvatarState.tick` (at the start of `AbstractClientPlayer.tick`).
-    pub fn tick(&mut self) {
+    /// `ClientAvatarState.tick` (at the start of `AbstractClientPlayer.tick`)
+    /// with the player's position then: `moveCloak` eases the cloak a quarter
+    /// of the way there, or puts it there from 10 blocks away.
+    pub fn tick(&mut self, position: [f64; 3]) {
         self.walk_dist_o = self.walk_dist;
+        self.cloak_o = self.cloak;
+        for i in 0..3 {
+            let d = position[i] - self.cloak[i];
+            if d > 10.0 || d < -10.0 {
+                self.cloak[i] = position[i];
+                self.cloak_o[i] = position[i];
+            } else {
+                self.cloak[i] += d * 0.25;
+            }
+        }
+    }
+    /// `AvatarRenderer.extractCapeState`: the cape's `capeFlap`, `capeLean`
+    /// and `capeLean2` (degrees) for the player at `position` (interpolated)
+    /// with its body turned `body_yaw` and its `fallFlyingScale`.
+    pub fn cape(
+        &self,
+        partial: f32,
+        position: [f64; 3],
+        body_yaw: f32,
+        fall_flying_scale: f32,
+    ) -> [f32; 3] {
+        let d: [f64; 3] = std::array::from_fn(|i| {
+            lerp_d(f64::from(partial), self.cloak_o[i], self.cloak[i]) - position[i]
+        });
+        let rad = f64::from(body_yaw * DEG_TO_RAD);
+        let (sin, cos) = (f64::from(trig::sin(rad)), f64::from(-trig::cos(rad)));
+        let mut flap = (d[1] as f32 * 10.0).clamp(-6.0, 32.0);
+        let lean = ((d[0] * sin + d[2] * cos) as f32 * 100.0 * (1.0 - fall_flying_scale))
+            .clamp(0.0, 150.0);
+        let lean2 = ((d[0] * cos - d[2] * sin) as f32 * 100.0).clamp(-20.0, 20.0);
+        let bob = self.interpolated_bob(partial);
+        let walk = lerp(partial, self.walk_dist_o, self.walk_dist);
+        flap += trig::sin(f64::from(walk * 6.0)) * 32.0 * bob;
+        [flap, lean, lean2]
     }
     /// `LocalPlayer.move`: `addWalkedDistance(Mth.length(dx, dz) * 0.6F)`
     /// with the float horizontal displacement.
@@ -772,8 +811,46 @@ pub fn bob_matrix(state: &BobState, damage_tilt_strength: f64, bob_view_option:
     pose
 }
 
+/// The spinning effect `GameRenderer.renderLevel` multiplies into the level's
+/// projection after the bob: a skew about a tilted axis, from a portal's or
+/// Nausea's intensity (already scaled by Distortion Effects) and the angle in
+/// degrees. The first-person hand keeps its own projection without it.
+pub fn spinning_effect_matrix(intensity: f32, angle_degrees: f32) -> glam::Mat4 {
+    if intensity <= 0.0 {
+        return glam::Mat4::IDENTITY;
+    }
+    let mut skew = 5.0 / (intensity * intensity + 5.0) - intensity * 0.04;
+    skew *= skew;
+    let axis = glam::Vec3::new(
+        0.0,
+        std::f32::consts::SQRT_2 / 2.0,
+        std::f32::consts::SQRT_2 / 2.0,
+    );
+    let angle = angle_degrees * DEG_TO_RAD;
+    glam::Mat4::from_axis_angle(axis, angle)
+        * glam::Mat4::from_scale(glam::Vec3::new(1.0 / skew, 1.0, 1.0))
+        * glam::Mat4::from_axis_angle(axis, -angle)
+}
+
 #[cfg(test)]
 mod tests {
+    /// `moveCloak` trails a quarter of the way, jumps from 10 blocks away; the
+    /// cape leans back as the player walks forward (south, body yaw 0).
+    #[test]
+    fn the_cloak_trails_the_player() {
+        let mut a = super::AvatarBob::default();
+        a.tick([0.0, 64.0, 0.0]);
+        assert_eq!((a.cloak, a.cloak_o), ([0.0, 64.0, 0.0], [0.0, 64.0, 0.0]));
+        a.tick([0.0, 64.0, 1.0]);
+        assert_eq!(a.cloak, [0.0, 64.0, 0.25]);
+        let [flap, lean, lean2] = a.cape(1.0, [0.0, 64.0, 1.0], 0.0, 0.0);
+        assert_eq!((flap, lean, lean2), (0.0, 75.0, 0.0));
+        // Falling lifts the flap, at most 32 degrees.
+        assert_eq!(a.cape(1.0, [0.0, 60.0, 0.25], 0.0, 0.0)[0], 32.0);
+        // Gliding takes the lean away.
+        assert_eq!(a.cape(1.0, [0.0, 64.0, 1.0], 0.0, 1.0)[1], 0.0);
+    }
+
     #[test]
     fn depth_far_covers_the_cloud_range() {
         // renderDistance 2 with the default Cloud Distance (128 chunks).

crates/horizon-client-render/src/chat.rs

@@ -16,6 +16,9 @@ use crate::{
 #[path = "chat_tests.rs"]
 mod tests;
 
+/// `CommandHistory.PERSISTED_COMMANDS_FILE_NAME` and its size cap.
+const COMMAND_HISTORY_FILE: &str = "command_history.txt";
+const MAX_PERSISTED_COMMAND_HISTORY: usize = 50;
 /// GuiMessageTag.systemSinglePlayer's indicator colour.
 pub const SYSTEM_INDICATOR: u32 = 0xD0D0D0;
 
@@ -80,6 +83,10 @@ impl ChatAbilities {
             ChatSource::Client => true,
         }
     }
+    /// `ChatAbilities.hasAnyRestrictions`: the Chat option takes something.
+    pub fn any_restriction(&self) -> bool {
+        *self != Self::new(ChatVisibility::Full)
+    }
     /// Whether the chat screen may send `input` (`hasAllowedInput`).
     pub fn allows(&self, input: &str) -> bool {
         if input.starts_with('/') {
@@ -185,6 +192,10 @@ pub struct Chat {
     lines: Vec<Line>,
     /// Sent messages and commands (ChatComponent.recentChat).
     pub recent: Vec<String>,
+    /// `CommandHistory`: the last commands, kept in `command_history.txt`
+    /// in the game folder once `load_history` has set it.
+    commands: Vec<String>,
+    history_file: Option<std::path::PathBuf>,
     scroll: usize,
     new_since_scroll: bool,
     pub options: ChatOptions,
@@ -310,6 +321,17 @@ impl Chat {
         self.lines.clear();
         self.scroll = 0;
     }
+    /// `new CommandHistory(gameFolder)`: the commands kept from earlier runs
+    /// start the chat's history (`ChatComponent`'s constructor).
+    pub fn load_history(&mut self, game_folder: &std::path::Path) {
+        let file = game_folder.join(COMMAND_HISTORY_FILE);
+        if let Ok(text) = std::fs::read_to_string(&file) {
+            self.commands = text.lines().map(str::to_owned).collect();
+            self.recent.extend(self.commands.iter().cloned());
+        }
+        self.history_file = Some(file);
+    }
+    /// `ChatComponent.addRecentChat`: a command also goes to the saved history.
     pub fn add_recent(&mut self, message: &str) {
         if self.recent.last().map(String::as_str) != Some(message) {
             if self.recent.len() >= 100 {
@@ -317,6 +339,21 @@ impl Chat {
             }
             self.recent.push(message.to_owned());
         }
+        if message.starts_with('/') && self.commands.last().map(String::as_str) != Some(message) {
+            if self.commands.len() >= MAX_PERSISTED_COMMAND_HISTORY {
+                self.commands.remove(0);
+            }
+            self.commands.push(message.to_owned());
+            if let Some(file) = &self.history_file {
+                let mut text = self.commands.join("\n");
+                text.push('\n');
+                if let Err(e) = std::fs::write(file, text) {
+                    log::error!(
+                        "Failed to write {COMMAND_HISTORY_FILE}, command history will be missing: {e}"
+                    );
+                }
+            }
+        }
     }
     pub fn reset_scroll(&mut self) {
         self.scroll = 0;
@@ -438,10 +475,71 @@ impl Chat {
         out.push(GuiDraw::Pop);
         out
     }
-    /// Draws [`Chat::layout`] into the HUD batch.
+    /// Draws [`Chat::layout`] into the HUD batch, and with the chat screen
+    /// open the restricted prompt above the lines.
     pub fn draw(&self, batch: &mut HudBatch, atlas: &HudAtlas, ticks: u64, focused: bool) {
         let draws = self.layout(batch.height as i32, ticks, focused);
         hud_layout::paint(batch, atlas, &draws);
+        if focused && self.abilities.any_restriction() {
+            let prompt = self.restricted_prompt(&atlas.font, batch.height as i32);
+            hud_layout::paint(batch, atlas, &prompt);
+        }
+    }
+    /// `ChatComponent.extractRenderState` for `FOREGROUND_RESTRICTED`: a
+    /// background row and the red, underlined "Chat is restricted" line in
+    /// the row above the messages, clipped to the chat's width.
+    fn restricted_prompt(&self, font: &crate::font::Font, height: i32) -> Vec<GuiDraw> {
+        let o = &self.options;
+        let scale = o.scale as f32;
+        let max_width = hud_layout::ceil(o.width_px() as f32 / scale);
+        let chat_bottom = hud_layout::floor((height - 40) as f32 / scale);
+        let entry_height = o.line_height();
+        let bottom_to_text =
+            (8.0 * (o.line_spacing + 1.0) - 4.0 * o.line_spacing + 0.5).floor() as i32;
+        let shown = self
+            .lines
+            .len()
+            .saturating_sub(self.scroll)
+            .min(self.lines_per_page(true));
+        let top = chat_bottom - (shown as i32 + 1) * entry_height;
+        let mut prompt = Text::translate("chat_screen.restricted", &[]).with_style(&Style {
+            color: Some(text::RED),
+            underlined: Some(true),
+            ..Style::default()
+        });
+        // ComponentRenderUtils.clipText.
+        let mut width = 0.0;
+        let fits = prompt
+            .chars()
+            .take_while(|(c, style)| {
+                width += font.advance(*c, style);
+                width <= max_width as f32
+            })
+            .count();
+        if fits < prompt.chars().count() {
+            prompt = prompt.slice(0, fits);
+        }
+        vec![
+            GuiDraw::Push(vec![
+                PoseOp::Scale(scale, scale),
+                PoseOp::Translate(4.0, 0.0),
+            ]),
+            hud_layout::fill(
+                -2,
+                top,
+                max_width + 4 + 4,
+                top + entry_height,
+                hud_layout::as8(o.background_opacity as f32) << 24,
+            ),
+            GuiDraw::Text {
+                text: prompt,
+                x: 0,
+                y: top + entry_height - bottom_to_text - 1,
+                color: hud_layout::white(o.opacity as f32 * 0.9 + 0.1),
+                shadow: true,
+            },
+            GuiDraw::Pop,
+        ]
     }
     /// The click action under a GUI-space cursor while chat is focused.
     pub fn click_at(
@@ -458,26 +556,34 @@ impl Chat {
     pub fn hover_at(&self, font: &crate::font::Font, height: i32, x: f64, y: f64) -> Option<Text> {
         self.style_at(font, height, x, y)?.hover.map(|h| *h)
     }
-    /// ChatComponent.getClickedComponentStyleAt.
-    fn style_at(
-        &self,
-        font: &crate::font::Font,
-        height: i32,
-        x: f64,
-        y: f64,
-    ) -> Option<crate::text::Style> {
+    /// The wrapped line under a GUI-space cursor while chat is focused, and
+    /// the cursor's x within it (the text starts at 0).
+    fn line_at(&self, height: i32, x: f64, y: f64) -> Option<(&Line, f64)> {
         let scale = self.options.scale as f32;
-        let mut x = x / f64::from(scale) - 4.0;
+        let x = x / f64::from(scale) - 4.0;
         let bottom = hud_layout::floor((height - 40) as f32 / scale);
         let from_bottom = f64::from(bottom) - y / f64::from(scale);
-        if x < 0.0 || x >= f64::from(self.max_width()) || from_bottom <= 0.0 {
+        if x >= f64::from(self.max_width()) || from_bottom <= 0.0 {
             return None;
         }
         let row = (from_bottom / f64::from(self.options.line_height())).ceil() as usize - 1;
         if row >= self.lines_per_page(true) {
             return None;
         }
-        let line = self.lines.get(self.scroll + row)?;
+        Some((self.lines.get(self.scroll + row)?, x))
+    }
+    /// ChatComponent.getClickedComponentStyleAt.
+    pub fn style_at(
+        &self,
+        font: &crate::font::Font,
+        height: i32,
+        x: f64,
+        y: f64,
+    ) -> Option<crate::text::Style> {
+        let (line, mut x) = self.line_at(height, x, y)?;
+        if x < 0.0 {
+            return None;
+        }
         let content = line.content.resolve_legacy();
         for (c, style) in content.chars() {
             x -= f64::from(font.advance(c, style));
@@ -487,6 +593,13 @@ impl Chat {
         }
         None
     }
+    /// Whether the cursor is on a line's indicator bar while chat is focused
+    /// (`DrawingFocusedGraphicsAccess.handleTag`), whose tooltip is the
+    /// message tag's text.
+    pub fn indicator_at(&self, height: i32, x: f64, y: f64) -> bool {
+        self.line_at(height, x, y)
+            .is_some_and(|(line, x)| line.indicator.is_some() && (-4.0..-2.0).contains(&x))
+    }
     /// Plain text of the newest messages (for tests and the control socket).
     pub fn recent_lines(&self, n: usize) -> Vec<String> {
         self.messages

crates/horizon-client-render/src/chunk.rs

@@ -2,9 +2,12 @@
 //! threads can mesh and light immutable snapshots while the game thread edits
 //! (copy-on-write through `Arc::make_mut`).
 use horizon_core::paletted::{PalettedContainer, Strategy};
+use horizon_world::nbt::{Compound, Tag};
 use horizon_world::registry::BlockStateId;
 use std::sync::{Arc, OnceLock};
 
+pub mod block_entity;
+
 pub const MIN_Y: i32 = -64;
 pub const HEIGHT: i32 = 384;
 pub const SECTIONS: usize = (HEIGHT / 16) as usize;
@@ -148,14 +151,14 @@ pub struct Chunk {
     /// Newly generated (not loaded from a save): eligible for generation-time spawns.
     pub fresh: bool,
     /// Block entities read from a save, moved into the world on arrival.
-    pub block_entities: Vec<((i32, i32, i32), crate::containers::BlockEntity)>,
+    pub block_entities: Vec<((i32, i32, i32), block_entity::BlockEntity)>,
     /// `CustomName` of the container block entities (shown as the screen title).
     pub block_names: Vec<((i32, i32, i32), String)>,
     /// Generation postprocessing marks (ProtoChunk.postProcessing) as world
     /// positions, applied once by LevelChunk.postProcessGeneration.
     pub postprocess: Vec<[i32; 3]>,
     /// Saved data Horizon keeps but does not simulate (save.rs).
-    pub saved: Option<Arc<crate::save::ChunkExtras>>,
+    pub saved: Option<Arc<ChunkExtras>>,
     /// Entities read from a save (vanilla entity NBT), spawned on arrival.
     pub entities: Vec<horizon_world::nbt::Tag>,
     /// Structure starts reaching into this chunk (`structures.References`):
@@ -309,6 +312,76 @@ impl Chunk {
     }
 }
 
+/// A proto chunk saved before it became final. Decoration writes into a
+/// chunk's neighbours, and decorated chunks wait for theirs, so the chunks
+/// past the finished ones hold writes that generating them again would lose
+/// (whole structure pieces, trees, ores). Vanilla saves its proto chunks too.
+pub struct SavedProto {
+    /// Blocks, scheduled ticks (in `saved`) and post-processing marks.
+    pub column: Chunk,
+    /// Decorated itself (`features`), not only written to by its neighbours
+    /// (`terrain`).
+    pub decorated: bool,
+    /// Block entity data in placement order, with `x`, `y` and `z`.
+    pub block_entities: Vec<Tag>,
+    /// Entities placed by structures, with absolute `Pos`.
+    pub entities: Vec<Tag>,
+}
+
+/// A container's loot table and what Horizon rolled from it. Vanilla keeps
+/// `LootTable` and `LootTableSeed` until the container is first opened;
+/// Horizon rolls when it generates or loads the chunk, and saves the table
+/// again while the container still holds exactly the rolled items.
+#[derive(Clone, Debug, PartialEq)]
+pub struct RolledLoot {
+    pub pos: (i32, i32, i32),
+    pub table: String,
+    /// The saved `LootTableSeed`, written back unless 0 (trySaveLootTable).
+    pub seed: Option<i64>,
+    /// The rolled `Items`.
+    pub items: Tag,
+}
+impl RolledLoot {
+    /// Puts the loot table back in place of `Items` while they are still the
+    /// roll; false once the container holds anything else.
+    pub fn restore(&self, map: &mut Compound) -> bool {
+        if map.get(&"Items".into()) != Some(&self.items) {
+            return false;
+        }
+        map.remove(&"Items".into());
+        map.insert("LootTable".into(), Tag::String(self.table.as_str().into()));
+        if let Some(seed) = self.seed.filter(|s| *s != 0) {
+            map.insert("LootTableSeed".into(), Tag::Long(seed));
+        }
+        true
+    }
+}
+
+/// Save data loaded with a chunk that Horizon keeps but does not simulate.
+#[derive(Clone, Debug, Default)]
+pub struct ChunkExtras {
+    /// Chunk root keys written back as loaded (structures, PostProcessing,
+    /// InhabitedTime, blending data, ...).
+    pub root: Compound,
+    /// Block entities Horizon does not model.
+    pub block_entities: Vec<Tag>,
+    /// The NBT of the modelled block entities as loaded, to restore the fields and
+    /// detail Horizon does not model when it saves them (`block_entity_nbt::overlay`).
+    pub block_entity_sources: Vec<((i32, i32, i32), Tag)>,
+    /// Every saved block entity's position in the order of the save's list,
+    /// the order `SerializableChunkData` puts them in the chunk's maps.
+    pub block_entity_order: Vec<(i32, i32, i32)>,
+    /// Scheduled ticks (`block_ticks`/`fluid_ticks`): delays relative to the
+    /// save time. Registered with the level's tick scheduler on arrival and
+    /// replaced with the scheduler's pending ticks when saving.
+    pub block_ticks: Vec<horizon_core::ticks::SavedTick>,
+    pub fluid_ticks: Vec<horizon_core::ticks::SavedTick>,
+    /// Game time written as `LastUpdate`.
+    pub last_update: i64,
+    /// Containers still holding their loot table's roll.
+    pub rolled_loot: Vec<RolledLoot>,
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;

crates/horizon-client-render/src/chunk/block_entity.rs

@@ -0,0 +1,469 @@
+//! Block entity data: what a chunk stores for its block entities (`BlockEntity`
+//! and its payloads). Plain data, as vanilla's block entities are world data;
+//! their behaviour lives with the features that use them (`containers`,
+//! `brewing`, `signs`, ...), which re-export these types under their old paths.
+use horizon_client_core::{text::Text, who::Who};
+use horizon_items::{banner_layer::BannerLayer, items::ItemStack};
+use horizon_world::{
+    level::sculk::SculkSpreader,
+    nbt::{Compound, Tag},
+};
+use std::{collections::HashMap, sync::Arc};
+
+/// An entity's UUID as its four ints (`UUIDUtil.CODEC`).
+pub type Uuid = [i32; 4];
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum FurnaceKind {
+    Furnace,
+    BlastFurnace,
+    Smoker,
+}
+#[derive(Clone, Debug)]
+pub struct Furnace {
+    pub kind: FurnaceKind,
+    /// input, fuel, result
+    pub items: [Option<ItemStack>; 3],
+    pub lit_remaining: i32,
+    pub lit_total: i32,
+    pub cooking_timer: i32,
+    pub cooking_total: i32,
+    pub speed: f32,
+    /// `AbstractFurnaceBlockEntity.recipesUsed`: how many of each recipe this furnace has
+    /// made since a player last took from its output. The experience is owed per recipe
+    /// rather than per item, and a save keeps it as the `RecipesUsed` compound.
+    pub recipes_used: HashMap<String, u32>,
+}
+#[derive(Clone, Debug)]
+pub enum BlockEntity {
+    Chest(Vec<Option<ItemStack>>),
+    Furnace(Furnace),
+    Brewing(Box<BrewingStand>),
+    /// Signs and hanging signs (`SignBlockEntity`).
+    Sign(SignData),
+    /// `JukeboxBlockEntity`: the record and its `JukeboxSongPlayer`.
+    Jukebox(Jukebox),
+    /// `BeaconBlockEntity`.
+    Beacon(Box<Beacon>),
+    /// `LecternBlockEntity`: the book and the open page.
+    Lectern(Lectern),
+    /// Sculk sensors, shriekers and catalysts (`crate::sculk`).
+    Sculk(Box<SculkEntity>),
+    /// `CreakingHeartBlockEntity`: its protector and the hurt emitter.
+    CreakingHeart(Box<CreakingHeart>),
+    /// `BannerBlockEntity`: the pattern layers.
+    Banner(Banner),
+    /// `CrafterBlockEntity`.
+    Crafter(Crafter),
+    /// `SpawnerBlockEntity` (`crate::mobs::spawner`).
+    Spawner(Box<Spawner>),
+    /// `TrialSpawnerBlockEntity` (`crate::mobs::trial_spawner`).
+    TrialSpawner(Box<TrialSpawner>),
+    /// `VaultBlockEntity` (`crate::vault`).
+    Vault(Box<Vault>),
+    /// `BeehiveBlockEntity` of beehives and bee nests (`crate::beehive`).
+    Beehive(Box<Beehive>),
+    /// `CommandBlockEntity` of the three command blocks (`crate::command_block`).
+    CommandBlock(Box<CommandBlock>),
+    /// `CampfireBlockEntity` of campfires and soul campfires.
+    Campfire(Box<Campfire>),
+    /// `SkullBlockEntity` of every skull and head block.
+    Skull(Skull),
+    /// `TheEndGatewayBlockEntity`: its age and configured destination.
+    EndGateway(EndGateway),
+    /// `DaylightDetectorBlockEntity`: no data, only the ticker
+    /// (`DaylightDetectorBlock.tickEntity`).
+    DaylightDetector,
+    /// `ChiseledBookShelfBlockEntity`: a `Container` of six one-book slots.
+    ChiseledBookshelf(Box<ChiseledBookshelf>),
+}
+/// `ChiseledBookShelfBlockEntity`: six slots and `lastInteractedSlot`.
+#[derive(Clone, Debug, PartialEq)]
+pub struct ChiseledBookshelf {
+    pub items: [Option<ItemStack>; 6],
+    pub last_slot: i32,
+}
+impl Default for ChiseledBookshelf {
+    fn default() -> Self {
+        Self {
+            items: Default::default(),
+            last_slot: -1,
+        }
+    }
+}
+/// `TheEndGatewayBlockEntity`.
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub struct EndGateway {
+    pub age: i64,
+    pub exit_portal: Option<[i32; 3]>,
+    pub exact_teleport: bool,
+}
+/// `CampfireBlockEntity`: four cooking slots, each with its
+/// `cookingProgress` and `cookingTime` (the recipe's).
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct Campfire {
+    pub items: [Option<ItemStack>; 4],
+    pub progress: [i32; 4],
+    pub total: [i32; 4],
+}
+/// `SkullBlockEntity`: the player profile the head shows (kept as loaded:
+/// a compound, or a string when it names a player only), the note block
+/// sound and `custom_name`.
+#[derive(Clone, Debug, Default)]
+pub struct Skull {
+    pub profile: Option<horizon_world::nbt::Tag>,
+    pub note_block_sound: Option<String>,
+    pub custom_name: Option<horizon_world::nbt::Tag>,
+    /// What `profile` draws, read from it once rather than every frame.
+    pub skin: Option<SkullSkin>,
+}
+/// `SkullBlockRenderer.getPlayerSkin` of a head's profile: its skin's URL
+/// with the `skins/<sha1>` sprite it downloads to, and the
+/// `DefaultPlayerSkin` drawn until that sprite is there (steve for a
+/// profile with no id).
+#[derive(Clone, Debug)]
+pub struct SkullSkin {
+    pub download: Option<(String, String)>,
+    /// `ResolvableProfile.nameOrId` when the profile is `Dynamic` (a name or
+    /// an id only): the key `skins::Resolver` resolves it by.
+    pub dynamic: Option<NameOrId>,
+    pub fallback: &'static str,
+}
+/// `Either<String, UUID>`: the key a `Dynamic` `ResolvableProfile` resolves
+/// by (`ResolvableProfile.nameOrId`).
+#[derive(Clone, Debug, PartialEq, Eq, Hash)]
+pub enum NameOrId {
+    Name(String),
+    Id(u128),
+}
+/// `CrafterBlockEntity`: nine slots that can be disabled, the powered flag
+/// and the ticks left in the crafting animation.
+#[derive(Clone, Debug, Default)]
+pub struct Crafter {
+    pub items: [Option<ItemStack>; 9],
+    pub disabled: [bool; 9],
+    pub triggered: bool,
+    pub crafting_ticks: i32,
+    /// The block state's `triggered` when last ticked (not saved): the block
+    /// entity flag follows it only when it changes (`CrafterBlock.neighborChanged`).
+    pub state_triggered: Option<bool>,
+}
+#[derive(Clone, Debug, Default)]
+pub struct Banner {
+    pub layers: Vec<BannerLayer>,
+    pub name: Option<String>,
+    /// Components not consumed by BannerBlockEntity's implicit fields.
+    pub components: horizon_world::nbt::Compound,
+}
+/// `CreakingHeartBlockEntity` (the logic is in `game/creaking.rs`).
+#[derive(Clone, Debug, Default)]
+pub struct CreakingHeart {
+    /// The protector: its entity id once resolved, and its UUID (the saved form).
+    pub creaking: Option<(Option<u32>, [i32; 4])>,
+    pub ticks_existed: i64,
+    pub ticker: i32,
+    /// Ticks left of the hurt effect (`emitter`) and where it heads.
+    pub emitter: i32,
+    pub emitter_target: Option<[f64; 3]>,
+    pub output_signal: i32,
+}
+#[derive(Clone, Debug, Default)]
+pub struct Lectern {
+    pub book: Option<ItemStack>,
+    pub page: i32,
+}
+#[derive(Clone, Debug, Default)]
+pub struct Beacon {
+    pub levels: i32,
+    /// Effect ids (`minecraft:speed`).
+    pub primary: Option<String>,
+    pub secondary: Option<String>,
+    /// Beam sections (RGB colour, height) and the ones being rebuilt.
+    pub sections: Vec<(u32, i32)>,
+    pub checking: Vec<(u32, i32)>,
+    pub last_check_y: i32,
+}
+#[derive(Clone, Debug, Default)]
+pub struct Jukebox {
+    pub record: Option<ItemStack>,
+    /// `ticks_since_song_started`, while a song plays.
+    pub ticks: i64,
+    pub playing: bool,
+}
+/// `BrewingStandBlockEntity` state. Slots: 0-2 bottles, 3 ingredient, 4 fuel.
+#[derive(Clone, Debug, Default)]
+pub struct BrewingStand {
+    pub items: [Option<ItemStack>; 5],
+    pub brew_time: i32,
+    pub total_brew_time: i32,
+    pub fuel: i32,
+    pub total_fuel: i32,
+    pub speed: f32,
+    pub ingredient: Option<Arc<str>>,
+    pub last_bottles: Option<[bool; 3]>,
+}
+/// One sign side (`SignText`).
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct SignText {
+    pub lines: [String; 4],
+    /// `DyeColor` id.
+    pub color: u8,
+    pub glowing: bool,
+}
+/// `SignBlockEntity` / `HangingSignBlockEntity` data.
+#[derive(Clone, Debug, Default, PartialEq, Eq)]
+pub struct SignData {
+    pub hanging: bool,
+    pub front: SignText,
+    pub back: SignText,
+    pub waxed: bool,
+}
+/// `VibrationInfo`.
+#[derive(Clone, Copy, Debug, PartialEq)]
+pub struct Info {
+    pub event: &'static str,
+    pub distance: f32,
+    pub pos: [f64; 3],
+    pub source: Option<Who>,
+    pub owner: Option<Who>,
+}
+/// `VibrationSelector`: the closest, then highest-frequency candidate of a tick.
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct Selector {
+    pub current: Option<(Info, i64)>,
+}
+/// `VibrationSystem.Data`.
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct Data {
+    pub current: Option<Info>,
+    pub travel: i32,
+    pub selector: Selector,
+}
+/// Which sculk block entity this is.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum SculkKind {
+    Sensor,
+    Calibrated,
+    Shrieker,
+    Catalyst,
+}
+/// `SculkSensorBlockEntity`, `CalibratedSculkSensorBlockEntity`,
+/// `SculkShriekerBlockEntity` and `SculkCatalystBlockEntity`.
+#[derive(Clone, Debug)]
+pub struct SculkEntity {
+    pub kind: SculkKind,
+    pub vibration: Data,
+    /// `last_vibration_frequency` (sensors).
+    pub last_frequency: i32,
+    /// `warning_level` (shriekers).
+    pub warning_level: i32,
+    /// The catalyst's charge cursors.
+    pub spreader: SculkSpreader,
+}
+/// `SpawnData.CustomSpawnRules`: the block and sky light the spawn block
+/// must have (inclusive ranges within 0..=15).
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub struct CustomSpawnRules {
+    pub block: (i32, i32),
+    pub sky: (i32, i32),
+}
+/// `SpawnData`: the entity to spawn, optional light rules and an equipment
+/// table (kept as loaded).
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct SpawnData {
+    pub entity: Compound,
+    pub custom_spawn_rules: Option<CustomSpawnRules>,
+    pub equipment: Option<Tag>,
+}
+/// Which `SpawnData` is next: one of the potentials (the same object in
+/// vanilla, so changing it changes the potential) or its own.
+#[derive(Clone, Debug, PartialEq)]
+pub enum Next {
+    Potential(usize),
+    Own(SpawnData),
+}
+/// `BaseSpawner`.
+#[derive(Clone, Debug, PartialEq)]
+pub struct Spawner {
+    pub spawn_delay: i32,
+    /// `SpawnPotentials`: data and weight.
+    pub potentials: Vec<(SpawnData, i32)>,
+    pub next: Option<Next>,
+    pub min_spawn_delay: i32,
+    pub max_spawn_delay: i32,
+    pub spawn_count: i32,
+    pub max_nearby_entities: i32,
+    pub required_player_range: i32,
+    pub spawn_range: i32,
+    /// The client copy's delay (`spawnDelay` on the client level), which
+    /// speeds the spin up as the next spawn nears.
+    pub client_delay: i32,
+    pub spin: f64,
+    pub o_spin: f64,
+}
+impl Default for Spawner {
+    fn default() -> Self {
+        Self {
+            spawn_delay: 20,
+            potentials: Vec::new(),
+            next: None,
+            min_spawn_delay: 200,
+            max_spawn_delay: 800,
+            spawn_count: 4,
+            max_nearby_entities: 6,
+            required_player_range: 16,
+            spawn_range: 4,
+            client_delay: 20,
+            spin: 0.0,
+            o_spin: 0.0,
+        }
+    }
+}
+/// `TrialSpawnerConfig`.
+#[derive(Clone, Debug, PartialEq)]
+pub struct TrialConfig {
+    pub spawn_range: i32,
+    pub total_mobs: f32,
+    pub simultaneous_mobs: f32,
+    pub total_mobs_added_per_player: f32,
+    pub simultaneous_mobs_added_per_player: f32,
+    pub ticks_between_spawn: i32,
+    pub spawn_potentials: Vec<(SpawnData, i32)>,
+    pub loot_tables_to_eject: Vec<(String, i32)>,
+    pub items_to_drop_when_ominous: String,
+}
+impl Default for TrialConfig {
+    /// `TrialSpawnerConfig.Builder`'s defaults.
+    fn default() -> Self {
+        Self {
+            spawn_range: 4,
+            total_mobs: 6.0,
+            simultaneous_mobs: 2.0,
+            total_mobs_added_per_player: 2.0,
+            simultaneous_mobs_added_per_player: 1.0,
+            ticks_between_spawn: 40,
+            spawn_potentials: Vec::new(),
+            loot_tables_to_eject: vec![
+                ("minecraft:spawners/trial_chamber/consumables".into(), 1),
+                ("minecraft:spawners/trial_chamber/key".into(), 1),
+            ],
+            items_to_drop_when_ominous:
+                "minecraft:spawners/trial_chamber/items_to_drop_when_ominous".into(),
+        }
+    }
+}
+/// A `Holder<TrialSpawnerConfig>` as saved: a registry id
+/// (`minecraft:trial_chamber/breeze/normal`) or an inline config.
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct ConfigSlot {
+    /// The value as loaded, written back as is; None for the default.
+    pub saved: Option<Tag>,
+    pub config: TrialConfig,
+}
+/// `TrialSpawner` with its `TrialSpawnerStateData`.
+#[derive(Clone, Debug, PartialEq)]
+pub struct TrialSpawner {
+    pub normal: ConfigSlot,
+    pub ominous: ConfigSlot,
+    pub target_cooldown_length: i32,
+    pub required_player_range: i32,
+    pub detected_players: Vec<Uuid>,
+    pub current_mobs: Vec<Uuid>,
+    pub cooldown_ends_at: i64,
+    pub next_mob_spawns_at: i64,
+    pub total_mobs_spawned: i32,
+    pub next_spawn_data: Option<SpawnData>,
+    pub ejecting_loot_table: Option<String>,
+    /// `isOminous`, set from the block on every server tick.
+    pub is_ominous: bool,
+    /// The server's display entity exists (`getOrCreateDisplayEntity`): it is
+    /// made once per loaded block entity and kept.
+    pub has_display: bool,
+    pub spin: f64,
+    pub o_spin: f64,
+    /// `getDispensingItems`, kept once rolled (not saved): the ominous items
+    /// and their weights (the rolled counts).
+    pub dispensing: Option<Vec<ItemStack>>,
+}
+impl Default for TrialSpawner {
+    fn default() -> Self {
+        Self {
+            normal: ConfigSlot::default(),
+            ominous: ConfigSlot::default(),
+            target_cooldown_length: 36000,
+            required_player_range: 14,
+            detected_players: Vec::new(),
+            current_mobs: Vec::new(),
+            cooldown_ends_at: 0,
+            next_mob_spawns_at: 0,
+            total_mobs_spawned: 0,
+            next_spawn_data: None,
+            ejecting_loot_table: None,
+            is_ominous: false,
+            has_display: false,
+            spin: 0.0,
+            o_spin: 0.0,
+            dispensing: None,
+        }
+    }
+}
+/// `VaultConfig`.
+#[derive(Clone, Debug, PartialEq)]
+pub struct VaultConfig {
+    pub loot_table: String,
+    pub activation_range: f64,
+    pub deactivation_range: f64,
+    /// None when the config has no key (`ItemStack.EMPTY`): the vault never opens.
+    pub key_item: Option<ItemStack>,
+    pub override_loot_table_to_display: Option<String>,
+}
+/// `VaultBlockEntity`: its config, server data and shared data.
+#[derive(Clone, Debug, PartialEq)]
+pub struct Vault {
+    pub config: VaultConfig,
+    /// `VaultServerData`, oldest rewarded player first.
+    pub rewarded_players: Vec<Uuid>,
+    pub state_updating_resumes_at: i64,
+    /// Popped from the end.
+    pub items_to_eject: Vec<ItemStack>,
+    pub total_ejections_needed: i32,
+    pub last_insert_fail_timestamp: i64,
+    /// `VaultSharedData`.
+    pub display_item: Option<ItemStack>,
+    pub connected_players: Vec<Uuid>,
+    pub connected_particles_range: f64,
+    /// The shared data changed since the last tick sent it.
+    pub shared_dirty: bool,
+    /// `VaultClientData`: the display item's spin and the previous tick's, in degrees.
+    pub spin: f32,
+    pub o_spin: f32,
+}
+/// `BeehiveBlockEntity`: the bees inside and the flower one of them knew.
+#[derive(Clone, Debug, Default, PartialEq)]
+pub struct Beehive {
+    pub bees: Vec<Occupant>,
+    pub flower: Option<[i32; 3]>,
+}
+/// `BeehiveBlockEntity.Occupant`: a bee's tag (with its `id`), its time in
+/// the hive and the time it stays at least.
+#[derive(Clone, Debug, PartialEq)]
+pub struct Occupant {
+    pub entity_data: Tag,
+    pub ticks_in_hive: i32,
+    pub min_ticks_in_hive: i32,
+}
+#[derive(Clone, Debug, PartialEq)]
+pub struct CommandBlock {
+    pub command: String,
+    pub success_count: i32,
+    /// `CustomName` as saved (a text component).
+    pub custom_name: Option<Tag>,
+    pub track_output: bool,
+    pub last_output: Option<Text>,
+    pub update_last_execution: bool,
+    /// The game time of the last run, -1 for none.
+    pub last_execution: i64,
+    pub powered: bool,
+    pub auto: bool,
+    pub condition_met: bool,
+}

crates/horizon-client-render/src/chunk_map.rs

@@ -76,14 +76,11 @@ impl<'a> IntoIterator for &'a ChunkMap {
     }
 }
 impl crate::light::LightWorld for ChunkMap {
-    fn state(&self, x: i32, y: i32, z: i32) -> Option<u32> {
-        self.columns.state(x, y, z)
+    fn section(&self, cx: i32, s: usize, cz: i32) -> Option<&Arc<crate::chunk::Section>> {
+        self.columns.section(cx, s, cz)
     }
-    fn light(&self, x: i32, y: i32, z: i32) -> Option<u8> {
-        self.columns.light(x, y, z)
-    }
-    fn set_light(&mut self, x: i32, y: i32, z: i32, packed: u8) {
-        self.columns.set_light(x, y, z, packed);
+    fn set_section_light(&mut self, cx: i32, s: usize, cz: i32, light: crate::chunk::Light) {
+        self.columns.set_section_light(cx, s, cz, light);
     }
 }
 
@@ -106,7 +103,13 @@ mod tests {
         for column in map.values_mut() {
             Arc::make_mut(column).light_loaded = true;
         }
-        crate::light::LightWorld::set_light(&mut map, 0, 0, 0, 0);
+        crate::light::LightWorld::set_section_light(
+            &mut map,
+            0,
+            0,
+            0,
+            crate::chunk::Light::Uniform(0),
+        );
         assert_eq!(inserted, map.membership_revision());
         map.remove(&(0, 0));
         map.insert((1, 0), chunk);

crates/horizon-client-render/src/clouds.rs

@@ -179,6 +179,8 @@ impl Mesh {
                         layer: 4,
                         color: u32::MAX,
                         light: shade,
+
+                        glint_uv: [0.0, 0.0],
                     });
                 }
             };

crates/horizon-client-render/src/collisions.rs

@@ -54,6 +54,27 @@ fn strider_liquid_shape() -> VoxelShape {
     VoxelShape::from_cube([1, 2, 1], &[true, false]).expect("a valid half-block column")
 }
 
+// Vanilla scopes this direction to Entity.move while a piston pushes it.
+thread_local! {
+    static PISTON_NOCLIP: std::cell::Cell<Option<horizon_core::geometry::Direction>> = const { std::cell::Cell::new(None) };
+}
+
+/// Suppress the moving part of pistons moving in this direction during a push.
+pub fn with_piston_noclip<T>(
+    direction: horizon_core::geometry::Direction,
+    f: impl FnOnce() -> T,
+) -> T {
+    struct Reset(Option<horizon_core::geometry::Direction>);
+    impl Drop for Reset {
+        fn drop(&mut self) {
+            PISTON_NOCLIP.with(|value| value.set(self.0));
+        }
+    }
+    let previous = PISTON_NOCLIP.with(|value| value.replace(Some(direction)));
+    let _reset = Reset(previous);
+    f()
+}
+
 pub struct SceneCollisions<'w, 'r> {
     pub world: &'w World,
     pub binding: &'w BlockCollisionRegistry<'r>,
@@ -140,8 +161,21 @@ impl<W: EntityMovementWorld<Error = io::Error>> EntityMovementWorld for EntityCo
         border.collision_shape().map(Some).map_err(io::Error::other)
     }
 }
-impl EntityCollisions<'_, SceneCollisions<'_, '_>> {
-    /// `SceneCollisions::resolve` that also stops at the entity boxes.
+impl<'a, W> EntityCollisions<'a, W>
+where
+    W: BlockCollisionWorld<Error = io::Error> + EntityMovementWorld<Error = io::Error>,
+{
+    /// `EntityCollisions` for a body the world border also stops: the border
+    /// and the body's own x and z (`WorldBorder.isInsideCloseToBorder`).
+    pub fn with_border(blocks: W, border: &'a BorderGeometry, at: [f64; 2]) -> Self {
+        Self {
+            blocks,
+            entities: &[],
+            border: Some((border, at)),
+        }
+    }
+    /// `SceneCollisions::resolve` that also stops at the entity boxes and,
+    /// with a border, at the world border's walls.
     pub fn resolve(
         &mut self,
         bounds: Aabb,
@@ -149,12 +183,11 @@ impl EntityCollisions<'_, SceneCollisions<'_, '_>> {
         max_step: f32,
         on_ground: bool,
     ) -> Result<Vec3> {
-        let context = self.blocks.context(bounds);
         Ok(resolve_world_movement(
             self,
             MovementRequest {
                 entity: EntityIdentity(0),
-                context,
+                context: CollisionContext::position(bounds.min_position().y),
                 bounds,
                 movement,
                 max_step,
@@ -324,7 +357,7 @@ impl DynamicSupportWorld for SceneCollisions<'_, '_> {
             return Ok(None);
         };
         pistons
-            .collision_shape(self, p, piston, None)
+            .collision_shape(self, p, piston, PISTON_NOCLIP.with(|value| value.get()))
             .map(Some)
             .map_err(io::Error::other)
     }
@@ -388,6 +421,42 @@ impl PowderSnowWorld for SceneCollisions<'_, '_> {
     }
 }
 
+/// A collision world without blocks: no chunk is resident, so only the
+/// world border stops a body.
+pub struct EmptyCollisions;
+
+impl BlockCollisionWorld for EmptyCollisions {
+    type Error = io::Error;
+    type Chunk = ChunkPos;
+    fn collision_chunk(&mut self, _: ChunkPos) -> io::Result<Option<ChunkPos>> {
+        Ok(None)
+    }
+    fn collision_block(&mut self, _: ChunkPos, _: BlockPos) -> io::Result<CollisionBlock> {
+        Err(io::Error::other("no chunk is resident"))
+    }
+    fn is_suffocating(&mut self, _: ChunkPos, _: CollisionBlock, _: BlockPos) -> io::Result<bool> {
+        Ok(false)
+    }
+    fn context_shape(
+        &mut self,
+        _: CollisionBlock,
+        _: BlockPos,
+        _: &CollisionContext<'_>,
+    ) -> io::Result<VoxelShape> {
+        Ok(VoxelShape::empty())
+    }
+}
+
+impl EntityMovementWorld for EmptyCollisions {
+    type Error = io::Error;
+    fn entity_collisions(&mut self, _: EntityIdentity, _: Aabb) -> io::Result<Vec<VoxelShape>> {
+        Ok(Vec::new())
+    }
+    fn movement_border(&mut self, _: EntityIdentity, _: Aabb) -> io::Result<Option<VoxelShape>> {
+        Ok(None)
+    }
+}
+
 /// Collision queries over any block lookup (test worlds without chunks):
 /// every chunk is present, nothing is suffocating, no entities collide.
 pub struct LookupCollisions<'w, 'r> {
@@ -475,3 +544,70 @@ impl PowderSnowWorld for LookupCollisions<'_, '_> {
         Ok(false)
     }
 }
+
+#[cfg(test)]
+mod piston_noclip_tests {
+    use super::*;
+    use horizon_core::geometry::Direction;
+
+    #[test]
+    fn piston_noclip_is_scoped_and_restored_after_unwind() {
+        assert_eq!(PISTON_NOCLIP.with(|value| value.get()), None);
+        with_piston_noclip(Direction::East, || {
+            assert_eq!(
+                PISTON_NOCLIP.with(|value| value.get()),
+                Some(Direction::East)
+            );
+            let _ =
+                std::panic::catch_unwind(|| with_piston_noclip(Direction::West, || panic!("test")));
+            assert_eq!(
+                PISTON_NOCLIP.with(|value| value.get()),
+                Some(Direction::East)
+            );
+        });
+        assert_eq!(PISTON_NOCLIP.with(|value| value.get()), None);
+    }
+}
+
+#[cfg(test)]
+mod border_movement_tests {
+    use super::*;
+
+    /// A border 10 wide around the origin: its wall's inner face is at x = 5.
+    fn border() -> BorderGeometry {
+        BorderGeometry::new([0.0, 0.0], 10.0, 29_999_984).expect("a border")
+    }
+
+    /// `WorldBorder.isInsideCloseToBorder` and `WorldBorder.getCollisionShape`:
+    /// a body inside close to the border collides with the border's walls.
+    #[test]
+    fn a_body_next_to_the_border_stops_at_its_wall() {
+        // A body 0.6 wide, 0.4 blocks short of the wall, moved east into it.
+        let bounds = Aabb::new(Vec3::new(4.0, 0.0, 0.0), Vec3::new(4.6, 1.8, 0.6));
+        let border = border();
+        let mut collisions = EntityCollisions::with_border(EmptyCollisions, &border, [4.3, 0.3]);
+        let moved = collisions
+            .resolve(bounds, Vec3::new(0.51, 0.0, 0.0), 0.0, false)
+            .expect("the movement resolves");
+        // The wall stops the body 0.4 blocks short of the whole move.
+        assert!(
+            (moved.x - 0.4).abs() < 1.0e-9,
+            "the body was not stopped by the border: {moved:?}"
+        );
+    }
+
+    /// Away from the border, the same body moves the whole way.
+    #[test]
+    fn a_body_away_from_the_border_moves_whole() {
+        let bounds = Aabb::new(Vec3::new(0.0, 0.0, 0.0), Vec3::new(0.6, 1.8, 0.6));
+        let border = border();
+        let mut collisions = EntityCollisions::with_border(EmptyCollisions, &border, [0.3, 0.3]);
+        let moved = collisions
+            .resolve(bounds, Vec3::new(0.51, 0.0, 0.0), 0.0, false)
+            .expect("the movement resolves");
+        assert!(
+            (moved.x - 0.51).abs() < 1.0e-9,
+            "the body did not move the whole way: {moved:?}"
+        );
+    }
+}

crates/horizon-client-render/src/command_block.rs

@@ -1,8 +1,10 @@
 //! `CommandBlockEntity` with its `BaseCommandBlock`: the command, the success
 //! count comparators read, the output it keeps, and the powered, automatic
 //! and condition flags `CommandBlock.tick` runs on.
-use crate::{
-    save::{number, text},
+pub use crate::chunk::block_entity::CommandBlock;
+use horizon_client_core::{
+    nbt_value::{number, text},
+    scoreboard,
     text::Text,
 };
 use horizon_world::nbt::Tag;
@@ -35,6 +37,23 @@ impl Mode {
             Self::Redstone => "minecraft:command_block",
         }
     }
+    /// `Enum.ordinal`, which `ServerboundSetCommandBlockPacket` writes.
+    pub fn ordinal(self) -> i32 {
+        match self {
+            Self::Sequence => 0,
+            Self::Auto => 1,
+            Self::Redstone => 2,
+        }
+    }
+    /// The mode of a packet's ordinal; `handleSetCommandBlock` treats any
+    /// other value as a plain command block (its `default` branch).
+    pub fn from_ordinal(ordinal: i32) -> Self {
+        match ordinal {
+            0 => Self::Sequence,
+            1 => Self::Auto,
+            _ => Self::Redstone,
+        }
+    }
     /// `CycleButton`: the next value, wrapping round.
     pub fn next(self) -> Self {
         match self {
@@ -59,22 +78,6 @@ pub fn automatic_block(name: &str) -> bool {
     name == "minecraft:chain_command_block"
 }
 
-#[derive(Clone, Debug, PartialEq)]
-pub struct CommandBlock {
-    pub command: String,
-    pub success_count: i32,
-    /// `CustomName` as saved (a text component).
-    pub custom_name: Option<Tag>,
-    pub track_output: bool,
-    pub last_output: Option<Text>,
-    pub update_last_execution: bool,
-    /// The game time of the last run, -1 for none.
-    pub last_execution: i64,
-    pub powered: bool,
-    pub auto: bool,
-    pub condition_met: bool,
-}
-
 impl Default for CommandBlock {
     fn default() -> Self {
         Self {
@@ -106,7 +109,7 @@ impl CommandBlock {
             last_output: track_output
                 .then(|| tag.get("LastOutput"))
                 .flatten()
-                .map(|t| crate::scoreboard::comp_text(&crate::scoreboard::tag_to_json(t))),
+                .map(|t| scoreboard::comp_text(&scoreboard::tag_to_json(t))),
             update_last_execution,
             last_execution: if update_last_execution {
                 number(tag.get("LastExecution")).unwrap_or(-1)
@@ -162,7 +165,7 @@ impl CommandBlock {
     pub fn name(&self) -> Text {
         self.custom_name.as_ref().map_or_else(
             || Text::literal("@"),
-            |t| crate::scoreboard::comp_text(&crate::scoreboard::tag_to_json(t)),
+            |t| scoreboard::comp_text(&scoreboard::tag_to_json(t)),
         )
     }
 }

crates/horizon-client-render/src/containers.rs

@@ -0,0 +1,543 @@
+//! Container block entities: chests/barrels (27 slots) and the three furnace
+//! kinds, ticking as `AbstractFurnaceBlockEntity.serverTick` with fuel times
+//! from the data-driven `context_int_provider`/`context_float_provider` files.
+pub use crate::chunk::block_entity::{
+    Banner, Beacon, BlockEntity, Campfire, ChiseledBookshelf, Crafter, CreakingHeart, EndGateway,
+    Furnace, FurnaceKind, Jukebox, Lectern, Skull, SkullSkin,
+};
+use crate::items::ItemStack;
+use std::collections::HashMap;
+
+impl FurnaceKind {
+    pub fn recipe_type(self) -> &'static str {
+        match self {
+            Self::Furnace => "minecraft:smelting",
+            Self::BlastFurnace => "minecraft:blasting",
+            Self::Smoker => "minecraft:smoking",
+        }
+    }
+    pub fn fast(self) -> bool {
+        self != Self::Furnace
+    }
+    pub fn from_block(name: &str) -> Option<Self> {
+        match name {
+            "minecraft:furnace" => Some(Self::Furnace),
+            "minecraft:blast_furnace" => Some(Self::BlastFurnace),
+            "minecraft:smoker" => Some(Self::Smoker),
+            _ => None,
+        }
+    }
+}
+/// The key `recipes_used` keeps a recipe under: its full id, as vanilla's `ResourceKey<Recipe>`
+/// writes it in `RecipesUsed`. Horizon's own recipe ids are file names without the namespace, so
+/// keeping both forms would write a key twice, and vanilla refuses such a furnace
+/// ("Duplicate entry for key").
+pub fn recipe_used_key(id: &str) -> String {
+    if id.contains(':') {
+        id.to_owned()
+    } else {
+        format!("minecraft:{id}")
+    }
+}
+/// A hopper's slots: the only plain container with five.
+pub const HOPPER_SLOTS: usize = 5;
+
+/// `getDefaultName` of the `BaseContainerBlockEntity` that `block` holds: the
+/// translation key of its menu's title when it has no custom name. Copper
+/// chests hold a `ChestBlockEntity`, shulker boxes of every colour a
+/// `ShulkerBoxBlockEntity`.
+pub fn default_name_key(block: &str) -> Option<&'static str> {
+    Some(match block {
+        "minecraft:chest" | "minecraft:trapped_chest" => "container.chest",
+        n if n.ends_with("copper_chest") => "container.chest",
+        "minecraft:barrel" => "container.barrel",
+        n if n.ends_with("shulker_box") => "container.shulkerBox",
+        "minecraft:dispenser" => "container.dispenser",
+        "minecraft:dropper" => "container.dropper",
+        "minecraft:hopper" => "container.hopper",
+        "minecraft:furnace" => "container.furnace",
+        "minecraft:smoker" => "container.smoker",
+        "minecraft:blast_furnace" => "container.blast_furnace",
+        "minecraft:brewing_stand" => "container.brewing",
+        "minecraft:crafter" => "container.crafter",
+        _ => return None,
+    })
+}
+
+/// `BaseContainerBlockEntity.getDisplayName` (`getName`), the title of the
+/// `ClientboundOpenScreenPacket` that opens it: the block entity's custom
+/// name (`CustomName`, a literal), else its default name.
+pub fn display_name(custom: Option<&str>, default_key: &str) -> horizon_world::nbt::Tag {
+    match custom {
+        Some(name) => horizon_protocol::text::literal(name),
+        None => horizon_protocol::text::translatable(default_key, &[]),
+    }
+}
+
+/// `ChestBlock.MENU_PROVIDER_COMBINER`'s `getDisplayName` for a double chest:
+/// the first half's custom name (the right half, `DoubleBlockCombiner`'s
+/// `FIRST`), else the second's, else `container.chestDouble`.
+pub fn double_chest_name(first: Option<&str>, second: Option<&str>) -> horizon_world::nbt::Tag {
+    display_name(first.or(second), "container.chestDouble")
+}
+
+impl Campfire {
+    /// `placeFood`'s slot: the first empty one, given the item's
+    /// `campfire_cooking` time; it takes one item of `held`.
+    pub fn place_food(&mut self, held: &mut ItemStack, cooking_time: i32) -> bool {
+        let Some(slot) = self.items.iter().position(Option::is_none) else {
+            return false;
+        };
+        self.total[slot] = cooking_time;
+        self.progress[slot] = 0;
+        self.items[slot] = Some(ItemStack {
+            count: 1,
+            ..held.clone()
+        });
+        held.count = held.count.saturating_sub(1);
+        true
+    }
+    /// `cookTick` (lit): each item's progress rises by one; the slots whose
+    /// progress reached their cooking time give up their item (the caller
+    /// drops its result).
+    pub fn cook_tick(&mut self) -> Vec<(usize, ItemStack)> {
+        let mut done = Vec::new();
+        for i in 0..4 {
+            if self.items[i].is_none() {
+                continue;
+            }
+            self.progress[i] += 1;
+            if self.progress[i] >= self.total[i]
+                && let Some(item) = self.items[i].take()
+            {
+                done.push((i, item));
+            }
+        }
+        done
+    }
+    /// `cooldownTick` (unlit): the progress falls by two, no lower than 0.
+    /// Whether anything changed (`setChanged`).
+    pub fn cooldown_tick(&mut self) -> bool {
+        let mut changed = false;
+        for i in 0..4 {
+            if self.progress[i] > 0 {
+                changed = true;
+                self.progress[i] = (self.progress[i] - 2).clamp(0, self.total[i]);
+            }
+        }
+        changed
+    }
+}
+impl Skull {
+    pub fn new(
+        profile: Option<horizon_world::nbt::Tag>,
+        note_block_sound: Option<String>,
+        custom_name: Option<horizon_world::nbt::Tag>,
+    ) -> Self {
+        let skin = profile.as_ref().map(SkullSkin::of);
+        Self {
+            profile,
+            note_block_sound,
+            custom_name,
+            skin,
+        }
+    }
+}
+impl SkullSkin {
+    pub fn of(profile: &horizon_world::nbt::Tag) -> Self {
+        let download = crate::skins::profile_skin_url_nbt(profile).and_then(|url| {
+            let location = crate::skins::skin_location(&crate::skins::texture_hash(&url)?);
+            Some((url, location))
+        });
+        // A `Dynamic` profile (a name or id only) resolves through the
+        // services when the skull is drawn.
+        let dynamic = crate::skins::dynamic_nbt(profile);
+        // DefaultPlayerSkin.get(id), or getDefaultSkin (slim steve) without an id.
+        let fallback = crate::skins::profile_uuid_nbt(profile)
+            .or_else(|| {
+                crate::skins::nbt_text(profile.get("name"))
+                    .map(|name| horizon_protocol::crypto::offline_uuid(&name))
+            })
+            .map_or("entity/player/slim/steve", crate::tab_list::default_skin);
+        Self {
+            download,
+            dynamic,
+            fallback,
+        }
+    }
+}
+/// The skull and head blocks (`SkullBlock`, `WallSkullBlock`): every
+/// `*_skull` and `*_head` but the piston's head.
+fn is_skull(name: &str) -> bool {
+    name.ends_with("_skull") || (name.ends_with("_head") && name != "minecraft:piston_head")
+}
+impl Crafter {
+    /// `slotCanBeDisabled`: only empty slots.
+    pub fn slot_can_be_disabled(&self, slot: usize) -> bool {
+        slot < 9 && self.items[slot].is_none()
+    }
+    /// `setSlotState`.
+    pub fn set_slot_state(&mut self, slot: usize, enabled: bool) {
+        if self.slot_can_be_disabled(slot) {
+            self.disabled[slot] = !enabled;
+        }
+    }
+    /// `getRedstoneSignal`: filled or disabled slots.
+    pub fn redstone_signal(&self) -> i32 {
+        (0..9)
+            .filter(|&i| self.items[i].is_some() || self.disabled[i])
+            .count() as i32
+    }
+    /// `canPlaceItem`: a hopper fills the smallest stacks first.
+    pub fn can_place(&self, slot: usize, _stack: &ItemStack, max_stack: u32) -> bool {
+        if slot >= 9 || self.disabled[slot] {
+            return false;
+        }
+        let Some(current) = &self.items[slot] else {
+            return true;
+        };
+        if current.count >= max_stack {
+            return false;
+        }
+        !(slot + 1..9).any(|i| {
+            !self.disabled[i]
+                && match &self.items[i] {
+                    None => true,
+                    Some(other) => {
+                        other.count < current.count && other.same_item_same_components(current)
+                    }
+                }
+        })
+    }
+}
+impl BlockEntity {
+    pub fn for_block(name: &str) -> Option<Self> {
+        if let Some(hanging) = crate::signs::sign_kind(name) {
+            return Some(Self::Sign(crate::signs::SignData {
+                hanging,
+                ..Default::default()
+            }));
+        }
+        if let Some(kind) = FurnaceKind::from_block(name) {
+            return Some(Self::Furnace(Furnace {
+                kind,
+                items: [None, None, None],
+                lit_remaining: 0,
+                lit_total: 0,
+                cooking_timer: 0,
+                cooking_total: 0,
+                speed: 1.0,
+                recipes_used: HashMap::new(),
+            }));
+        }
+        if name == "minecraft:creaking_heart" {
+            return Some(Self::CreakingHeart(Box::default()));
+        }
+        if name == "minecraft:spawner" {
+            return Some(Self::Spawner(Box::default()));
+        }
+        if name == "minecraft:trial_spawner" {
+            return Some(Self::TrialSpawner(Box::default()));
+        }
+        if name == "minecraft:vault" {
+            return Some(Self::Vault(Box::default()));
+        }
+        if name == "minecraft:beehive" || name == "minecraft:bee_nest" {
+            return Some(Self::Beehive(Box::default()));
+        }
+        if name == "minecraft:lectern" {
+            return Some(Self::Lectern(Lectern::default()));
+        }
+        if crate::command_block::Mode::of_block(name).is_some() {
+            // CommandBlock.newBlockEntity: setAutomatic(this.automatic).
+            return Some(Self::CommandBlock(Box::new(
+                crate::command_block::CommandBlock {
+                    auto: crate::command_block::automatic_block(name),
+                    ..Default::default()
+                },
+            )));
+        }
+        if let Some(sculk) = crate::sculk::SculkEntity::for_block(name) {
+            return Some(Self::Sculk(Box::new(sculk)));
+        }
+        if name == "minecraft:crafter" {
+            // CrafterBlock.newBlockEntity copies the placed state's flag: the
+            // first tick sees it as a change from untriggered.
+            return Some(Self::Crafter(Crafter {
+                state_triggered: Some(false),
+                ..Crafter::default()
+            }));
+        }
+        if name.ends_with("_banner") {
+            return Some(Self::Banner(Banner::default()));
+        }
+        if is_skull(name) {
+            return Some(Self::Skull(Skull::default()));
+        }
+        if name == "minecraft:end_gateway" {
+            return Some(Self::EndGateway(EndGateway::default()));
+        }
+        if name == "minecraft:daylight_detector" {
+            return Some(Self::DaylightDetector);
+        }
+        if name == "minecraft:beacon" {
+            return Some(Self::Beacon(Box::new(Beacon {
+                last_check_y: i32::MIN / 2,
+                ..Default::default()
+            })));
+        }
+        if name == "minecraft:brewing_stand" {
+            return Some(Self::Brewing(Box::new(crate::brewing::BrewingStand::new())));
+        }
+        if name == "minecraft:campfire" || name == "minecraft:soul_campfire" {
+            return Some(Self::Campfire(Box::default()));
+        }
+        if name == "minecraft:chiseled_bookshelf" {
+            return Some(Self::ChiseledBookshelf(Box::default()));
+        }
+        let size = match name {
+            "minecraft:chest" | "minecraft:trapped_chest" | "minecraft:barrel" => 27,
+            n if n.ends_with("copper_chest") => 27,
+            "minecraft:hopper" => HOPPER_SLOTS,
+            "minecraft:dispenser" | "minecraft:dropper" => 9,
+            n if n.ends_with("shulker_box") => 27,
+            _ => return None,
+        };
+        Some(Self::Chest(vec![None; size]))
+    }
+    pub fn id(&self) -> &'static str {
+        match self {
+            Self::Chest(items) => match items.len() {
+                HOPPER_SLOTS => "minecraft:hopper",
+                9 => "minecraft:dispenser",
+                _ => "minecraft:chest",
+            },
+            Self::Furnace(f) => match f.kind {
+                FurnaceKind::Furnace => "minecraft:furnace",
+                FurnaceKind::BlastFurnace => "minecraft:blast_furnace",
+                FurnaceKind::Smoker => "minecraft:smoker",
+            },
+            Self::Brewing(_) => "minecraft:brewing_stand",
+            Self::Sign(s) => s.id(),
+            Self::Jukebox(_) => "minecraft:jukebox",
+            Self::Beacon(_) => "minecraft:beacon",
+            Self::Lectern(_) => "minecraft:lectern",
+            Self::Sculk(s) => s.id(),
+            Self::Banner(_) => "minecraft:banner",
+            Self::Crafter(_) => "minecraft:crafter",
+            Self::CreakingHeart(_) => "minecraft:creaking_heart",
+            Self::Spawner(_) => "minecraft:mob_spawner",
+            Self::TrialSpawner(_) => "minecraft:trial_spawner",
+            Self::Vault(_) => "minecraft:vault",
+            Self::Beehive(_) => "minecraft:beehive",
+            Self::CommandBlock(_) => "minecraft:command_block",
+            Self::Skull(_) => "minecraft:skull",
+            Self::EndGateway(_) => "minecraft:end_gateway",
+            Self::DaylightDetector => "minecraft:daylight_detector",
+            Self::Campfire(_) => "minecraft:campfire",
+            Self::ChiseledBookshelf(_) => "minecraft:chiseled_bookshelf",
+        }
+    }
+    pub fn contents(&self) -> Vec<ItemStack> {
+        match self {
+            Self::Chest(items) => items.iter().flatten().cloned().collect(),
+            Self::Furnace(f) => f.items.iter().flatten().cloned().collect(),
+            Self::Brewing(b) => b.items.iter().flatten().cloned().collect(),
+            Self::Sign(_) => Vec::new(),
+            Self::Jukebox(j) => j.record.iter().cloned().collect(),
+            Self::Beacon(_)
+            | Self::CreakingHeart(_)
+            | Self::Spawner(_)
+            | Self::TrialSpawner(_)
+            | Self::Vault(_)
+            | Self::Beehive(_)
+            | Self::CommandBlock(_)
+            | Self::EndGateway(_)
+            | Self::Skull(_)
+            | Self::DaylightDetector => Vec::new(),
+            Self::Lectern(l) => l.book.iter().cloned().collect(),
+            Self::Sculk(_) => Vec::new(),
+            Self::Banner(_) => Vec::new(),
+            Self::Crafter(c) => c.items.iter().flatten().cloned().collect(),
+            Self::Campfire(c) => c.items.iter().flatten().cloned().collect(),
+            Self::ChiseledBookshelf(b) => b.items.iter().flatten().cloned().collect(),
+        }
+    }
+    pub fn slots(&self) -> &[Option<ItemStack>] {
+        match self {
+            Self::Chest(items) => items,
+            Self::Furnace(f) => &f.items,
+            Self::Brewing(b) => &b.items,
+            Self::Sign(_)
+            | Self::Jukebox(_)
+            | Self::Beacon(_)
+            | Self::Lectern(_)
+            | Self::Sculk(_)
+            | Self::Banner(_)
+            | Self::EndGateway(_)
+            | Self::Skull(_)
+            | Self::DaylightDetector => &[],
+            Self::Crafter(c) => &c.items,
+            Self::ChiseledBookshelf(b) => &b.items,
+            Self::CreakingHeart(_)
+            | Self::Spawner(_)
+            | Self::TrialSpawner(_)
+            | Self::Vault(_)
+            | Self::Beehive(_)
+            | Self::CommandBlock(_)
+            // Not a Container (only Clearable): hoppers don't reach in.
+            | Self::Campfire(_) => &[],
+        }
+    }
+    pub fn slots_mut(&mut self) -> &mut [Option<ItemStack>] {
+        match self {
+            Self::Chest(items) => items,
+            Self::Furnace(f) => &mut f.items,
+            Self::Brewing(b) => &mut b.items,
+            Self::Sign(_)
+            | Self::Jukebox(_)
+            | Self::Beacon(_)
+            | Self::Lectern(_)
+            | Self::Sculk(_)
+            | Self::Banner(_)
+            | Self::EndGateway(_)
+            | Self::Skull(_)
+            | Self::DaylightDetector => &mut [],
+            Self::Crafter(c) => &mut c.items,
+            Self::ChiseledBookshelf(b) => &mut b.items,
+            Self::CreakingHeart(_)
+            | Self::Spawner(_)
+            | Self::TrialSpawner(_)
+            | Self::Vault(_)
+            | Self::Beehive(_)
+            | Self::CommandBlock(_)
+            | Self::Campfire(_) => &mut [],
+        }
+    }
+}
+pub use crate::providers::Providers;
+
+/// A `ChestBlock`, which `ChestBlock.combine` can join into a double chest:
+/// chests, trapped chests and copper chests in every weathering state, waxed
+/// or not (`CopperChestBlock` extends `ChestBlock`). Ender chests are
+/// `EnderChestBlock`s and always single.
+pub fn is_chest_block(name: &str) -> bool {
+    matches!(name, "minecraft:chest" | "minecraft:trapped_chest") || name.ends_with("copper_chest")
+}
+
+/// A chest block's name with its `type` and `facing` properties.
+#[derive(Clone, Copy, Debug)]
+pub struct ChestHalf<'a> {
+    pub block: &'a str,
+    pub kind: &'a str,
+    pub facing: &'a str,
+}
+
+impl ChestHalf<'_> {
+    /// `ChestBlock.getConnectedDirection` as an (x, z) step to the other
+    /// half: clockwise from the facing for a left half, counter-clockwise for
+    /// a right one. None for a single chest.
+    pub fn connected_step(&self) -> Option<(i32, i32)> {
+        let step = |facing: &str| match facing {
+            "north" => Some((0, -1)),
+            "south" => Some((0, 1)),
+            "west" => Some((-1, 0)),
+            "east" => Some((1, 0)),
+            _ => None,
+        };
+        let (x, z) = step(self.facing)?;
+        // Turning clockwise seen from above takes (x, z) to (-z, x).
+        match self.kind {
+            "left" => Some((-z, x)),
+            "right" => Some((z, -x)),
+            _ => None,
+        }
+    }
+
+    /// `DoubleBlockCombiner.combineWithNeigbour` as `ChestBlock.combine` calls
+    /// it: `other`, the block in this half's connected direction, is its other
+    /// half when it is the same block, a half of the other side and faces the
+    /// same way. Copper chests in different weathering states never join
+    /// (`CopperChestBlock` keeps both halves in one state instead).
+    pub fn pairs_with(&self, other: &ChestHalf) -> bool {
+        is_chest_block(self.block)
+            && self.kind != "single"
+            && other.block == self.block
+            && other.kind != "single"
+            && other.kind != self.kind
+            && other.facing == self.facing
+    }
+}
+
+/// `AbstractFurnaceBlockEntity.createExperience`: `count * experience`, floored, and one
+/// more with the chance of what is left over (a level random draw only when there is some).
+pub fn create_experience(
+    count: u32,
+    experience: f32,
+    random: &mut impl horizon_core::random::RandomSource,
+) -> u32 {
+    let total = count as f32 * experience;
+    let whole = total.floor();
+    let fraction = total - whole;
+    let mut xp = whole.max(0.0) as u32;
+    if fraction != 0.0 && random.next_float() < fraction {
+        xp += 1;
+    }
+    xp
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use horizon_core::random::{LegacyRandom, RandomSource};
+
+    #[test]
+    fn campfire_slots_take_food_cook_it_and_cool_down() {
+        let mut c = Campfire::default();
+        let mut beef = ItemStack::new("minecraft:beef", 2);
+        // placeFood: the first free slot, one item, its recipe's time.
+        assert!(c.place_food(&mut beef, 600));
+        assert_eq!(beef.count, 1);
+        assert_eq!(c.items[0].as_ref().map(|s| s.count), Some(1));
+        assert_eq!((c.progress[0], c.total[0]), (0, 600));
+        let mut fish = ItemStack::new("minecraft:cod", 1);
+        assert!(c.place_food(&mut fish, 3));
+        assert_eq!(c.items[1].as_ref().map(|s| &*s.item), Some("minecraft:cod"));
+        // cookTick: the cod is done on its third tick, the beef keeps cooking.
+        assert!(c.cook_tick().is_empty());
+        assert!(c.cook_tick().is_empty());
+        let done = c.cook_tick();
+        assert_eq!(done.len(), 1);
+        assert_eq!((done[0].0, &*done[0].1.item), (1, "minecraft:cod"));
+        assert!(c.items[1].is_none());
+        assert_eq!(c.progress[0], 3);
+        // cooldownTick: two a tick, never below zero.
+        assert!(c.cooldown_tick());
+        assert_eq!(c.progress[0], 1);
+        assert!(c.cooldown_tick());
+        assert_eq!(c.progress[0], 0);
+        // Full: four slots, no fifth.
+        for _ in 0..3 {
+            let mut more = ItemStack::new("minecraft:potato", 1);
+            assert!(c.place_food(&mut more, 600));
+        }
+        let mut fifth = ItemStack::new("minecraft:potato", 1);
+        assert!(!c.place_food(&mut fifth, 600));
+        assert_eq!(fifth.count, 1);
+    }
+
+    /// A whole amount pays itself without a draw; a fraction is a chance of one more.
+    #[test]
+    fn create_experience_rounds_the_fraction_by_chance() {
+        let mut random = LegacyRandom::new(7);
+        let mut untouched = LegacyRandom::new(7);
+        assert_eq!(create_experience(4, 0.5, &mut random), 2);
+        assert_eq!(create_experience(3, 0.0, &mut random), 0);
+        assert_eq!(random.next_long(), untouched.next_long());
+        let paid: u32 = (0..1000)
+            .map(|_| create_experience(1, 0.35, &mut random))
+            .sum();
+        assert!((250..450).contains(&paid), "{paid}");
+        assert!((0..100).all(|_| (1..=2).contains(&create_experience(1, 1.7, &mut random))));
+    }
+}

crates/horizon-client-render/src/crash.rs

@@ -105,9 +105,13 @@ impl Report {
     }
 }
 
-/// The release this binary is (`v0.2.3`); for a release from before 0.2, its tag and the client's
-/// crate version; for a build from source, that version alone.
+/// The release this binary is (`v0.2.3`); a nightly's label (`Nightly 2026-10-28 · 0c02067`); for a
+/// release from before 0.2, its tag and the client's crate version; for a build from source, that
+/// version alone.
 pub fn version() -> String {
+    if let Some(label) = horizon_core::release::nightly_label() {
+        return label;
+    }
     let version = env!("CARGO_PKG_VERSION");
     match (horizon_core::release::RELEASE, release_tag()) {
         (Some(_), Some(tag)) => tag,
@@ -117,8 +121,12 @@ pub fn version() -> String {
 }
 
 /// The release this binary came with: the version release.yml built in (docs/versioning.md), else
-/// the folder the launcher installed it in, named after the tag (releases from before 0.2).
+/// the folder the launcher installed it in, named after the tag (releases from before 0.2). A
+/// nightly is its version as the launcher installs it (`nightly-2026-10-28-0c02067`).
 pub fn release_tag() -> Option<String> {
+    if let Some(nightly) = horizon_core::release::nightly_version() {
+        return Some(nightly);
+    }
     if let Some(version) = horizon_core::release::RELEASE {
         return Some(format!("v{version}"));
     }
@@ -318,16 +326,18 @@ fn panic_message(info: &std::panic::PanicHookInfo) -> String {
 /// frames go. Paths inside the workspace lose the build machine's prefix.
 pub fn stack_lines(backtrace: &str, from_panic: bool) -> String {
     // The workspace as it was on the machine that built this binary (it need not exist here).
-    let manifest = env!("CARGO_MANIFEST_DIR");
+    // A report names workspace files the same way on every host, whatever
+    // separator the build machine used.
+    let manifest = env!("CARGO_MANIFEST_DIR").replace('\\', "/");
     let root = manifest
-        .strip_suffix("crates/horizon-client")
-        .unwrap_or(manifest);
+        .strip_suffix("crates/horizon-client-render")
+        .unwrap_or(&manifest);
     let mut frames: Vec<(String, Option<String>)> = Vec::new();
     for line in backtrace.lines() {
         let line = line.trim();
         if let Some(at) = line.strip_prefix("at ") {
             if let Some(frame) = frames.last_mut() {
-                frame.1 = Some(short_path(at, root).to_owned());
+                frame.1 = Some(short_path(&at.replace('\\', "/"), root).to_owned());
             }
         } else if let Some((n, name)) = line.split_once(": ")
             && n.chars().all(|c| c.is_ascii_digit())
@@ -525,6 +535,11 @@ mod tests {
     #[test]
     fn a_release_reports_its_built_in_version() {
         // release.yml builds with HORIZON_VERSION (docs/versioning.md): `v0.2.3`, wherever it is installed.
+        if let Some(label) = horizon_core::release::nightly_label() {
+            assert_eq!(super::version(), label);
+            assert_eq!(release_tag(), horizon_core::release::nightly_version());
+            return;
+        }
         match horizon_core::release::RELEASE {
             Some(version) => {
                 assert_eq!(release_tag(), Some(format!("v{version}")));
@@ -590,7 +605,7 @@ mod tests {
         );
         assert_eq!(
             stack_lines(&bt, true),
-            "horizon_client::crash::debug_crash_tick (crates/horizon-client/src/crash.rs:359:9)\nwinit::dispatch (winit-0.30.13/src/event_loop.rs:642:56)\nmain\n"
+            "horizon_client::crash::debug_crash_tick (crates/horizon-client-render/src/crash.rs:359:9)\nwinit::dispatch (winit-0.30.13/src/event_loop.rs:642:56)\nmain\n"
         );
     }
 

crates/horizon-client-render/src/effects.rs

@@ -2,7 +2,7 @@
 //! add/update with hidden effects, per-tick application of the periodic
 //! effects (regeneration, poison, wither, hunger, saturation, instant
 //! effects), and the derived flags the movement and damage code read.
-use crate::brewing;
+use horizon_client_core::potions;
 
 #[derive(Clone, Debug, PartialEq)]
 pub struct EffectInstance {
@@ -29,6 +29,10 @@ impl EffectInstance {
     fn infinite(&self) -> bool {
         self.duration == -1
     }
+    /// `MobEffectInstance.endsWithin`.
+    pub fn ends_within(&self, ticks: i32) -> bool {
+        !self.infinite() && self.duration <= ticks
+    }
     fn shorter_than(&self, other: &Self) -> bool {
         !self.infinite() && (self.duration < other.duration || other.infinite())
     }
@@ -129,15 +133,16 @@ fn periodic(id: &str, tick: i32, amp: i32) -> Option<EffectAction> {
         _ => None,
     }
 }
-/// `InstantenousMobEffect.applyInstantenousEffect` (potions apply these directly).
+/// `HealOrHarmMobEffect.applyInstantaneousEffect` (potions apply these directly;
+/// the amount rounds to the nearest whole point).
 pub fn instant(id: &str, amp: i32, scale: f64) -> Option<EffectAction> {
     match id {
         "instant_health" => Some(EffectAction::Heal(
-            (scale * f64::from(4 << amp.min(30))) as i32 as f32,
+            (scale * f64::from(4 << amp.min(30)) + 0.5) as i32 as f32,
         )),
         "instant_damage" => Some(EffectAction::Hurt(
             "minecraft:magic",
-            (scale * f64::from(6 << amp.min(30))) as i32 as f32,
+            (scale * f64::from(6 << amp.min(30)) + 0.5) as i32 as f32,
         )),
         "saturation" => Some(EffectAction::Eat(amp + 1, 1.0)),
         _ => None,
@@ -179,13 +184,14 @@ impl PlayerEffects {
         self.list.clear();
     }
     /// The effects of a saved player (`Player.active_effects`: id,
-    /// duration, amplifier, ambient, visible).
+    /// duration, amplifier, ambient, particles visible).
     pub fn from_saved(saved: &[(String, i32, i32, bool, bool)]) -> Self {
         let mut effects = Self::default();
-        for (id, duration, amplifier, ambient, _) in saved {
-            if let Some(def) = brewing::effect(id) {
+        for (id, duration, amplifier, ambient, particles) in saved {
+            if let Some(def) = potions::effect(id) {
                 let mut e = EffectInstance::new(def.id, *duration, *amplifier);
                 e.ambient = *ambient;
+                e.visible = *particles;
                 effects.add(e);
             }
         }
@@ -213,8 +219,9 @@ impl PlayerEffects {
     }
     /// `LivingEntity.tickEffects` (server part) with the omens' effect ticks:
     /// `omen` answers `BadOmenMobEffect` (every tick) and `RaidOmenMobEffect`
-    /// (on its last tick). Returns the actions to apply, in order, and
-    /// whether Raid Omen was newly added.
+    /// (on its last tick); `absorption_empty` is `AbsorptionMobEffect`'s
+    /// answer: the effect ends once the absorption is used up. Returns the
+    /// actions to apply, in order, and whether Raid Omen was newly added.
     ///
     /// Bad Omen turning into a new Raid Omen adds an entry to the map being
     /// iterated: vanilla's iterator then throws a
@@ -224,6 +231,7 @@ impl PlayerEffects {
     pub fn tick_with(
         &mut self,
         omen: &mut dyn FnMut(&EffectInstance) -> OmenTick,
+        absorption_empty: bool,
     ) -> (Vec<EffectAction>, bool) {
         self.tick_count = self.tick_count.wrapping_add(1);
         let mut actions = Vec::new();
@@ -246,6 +254,7 @@ impl PlayerEffects {
             let answer = match e.id {
                 "bad_omen" => omen(e),
                 "raid_omen" if t == 1 => omen(e),
+                "absorption" if absorption_empty => OmenTick::Remove,
                 _ => OmenTick::Continue,
             };
             match answer {
@@ -302,10 +311,10 @@ impl PlayerEffects {
     ) -> (Vec<EffectInstance>, Vec<EffectAction>) {
         let mut lasting = Vec::new();
         let mut now = Vec::new();
-        if let Some(def) = potion.and_then(brewing::potion) {
+        if let Some(def) = potion.and_then(potions::potion) {
             for (id, duration, amp) in def.effects {
-                let id = brewing::effect(id).map_or("speed", |e| e.id);
-                if brewing::effect(id).is_some_and(|e| e.instant) {
+                let id = potions::effect(id).map_or("speed", |e| e.id);
+                if potions::effect(id).is_some_and(|e| e.instant) {
                     now.extend(instant(id, *amp, 1.0));
                 } else {
                     // withScaledDuration: max(floor(d * scale), 1).
@@ -465,13 +474,13 @@ mod tests {
         };
         // The first tick adds Raid Omen and stops there (the iterator's
         // ConcurrentModificationException): Bad Omen and Speed stay as they were.
-        let (_, added) = fx.tick_with(&mut convert);
+        let (_, added) = fx.tick_with(&mut convert, false);
         assert!(added);
         assert_eq!(fx.get("bad_omen").unwrap().duration, 100);
         assert_eq!(fx.get("speed").unwrap().duration, 50);
         assert_eq!(fx.get("raid_omen").unwrap().duration, 600);
         // The second refreshes Raid Omen and drops Bad Omen.
-        let (_, added) = fx.tick_with(&mut convert);
+        let (_, added) = fx.tick_with(&mut convert, false);
         assert!(!added);
         assert!(fx.get("bad_omen").is_none());
         assert_eq!(fx.get("speed").unwrap().duration, 49);
@@ -486,9 +495,9 @@ mod tests {
             seen.push(e.duration);
             OmenTick::Remove
         };
-        fx.tick_with(&mut watch);
+        fx.tick_with(&mut watch, false);
         assert!(fx.get("raid_omen").is_some());
-        fx.tick_with(&mut watch);
+        fx.tick_with(&mut watch, false);
         assert!(fx.get("raid_omen").is_none());
         assert_eq!(seen, vec![1]);
     }

crates/horizon-client-render/src/entity.wgsl

@@ -14,19 +14,27 @@ struct Globals {
     // Atlas rects (u0, v0, width, height) of end_sky.png and end_portal.png.
     end_portal_sprites: array<vec4<f32>, 2>,
     // x: vanilla's GameTime ((game time % 24000 + partial tick) / 24000)
-    // y: Nether cardinal lighting, z: how many dynamic_lights are set.
+    // y: Nether cardinal lighting, z: how many dynamic_lights are set,
+    // w: the glint scroll clock (`Glint::scroll_ticks`).
     time: vec4<f32>,
     crumbling_sprite: vec4<f32>,
     // Selection outline parameters (read by terrain.wgsl).
     outline_params: vec4<f32>,
     // Horizon Extras' dynamic lights: camera-relative position and level (dynamic_light.rs).
     dynamic_lights: array<vec4<f32>, 16>,
+    sunrise_fan: array<vec4<f32>, 32>,
 }
 @group(0) @binding(0) var<uniform> globals: Globals;
 @group(0) @binding(1) var atlas: texture_2d<f32>;
 @group(0) @binding(2) var atlas_sampler: sampler;
 @group(0) @binding(3) var lightmap: texture_2d<f32>;
 @group(0) @binding(4) var lightmap_sampler: sampler;
+// enchanted_glint_item on its own repeating texture (vanilla's GlintSampler).
+@group(0) @binding(5) var glint_tex: texture_2d<f32>;
+@group(0) @binding(6) var glint_sampler: sampler;
+// The armour layers' GlintSampler: vanilla samples enchanted_glint_armor with
+// the same repeating, linearly filtered sampler as the item glint.
+@group(0) @binding(7) var glint_armor_tex: texture_2d<f32>;
 struct Out {
     @builtin(position) clip: vec4<f32>,
     @location(0) uv: vec2<f32>,
@@ -44,6 +52,11 @@ struct Out {
     // entity.vsh's lightMapColor, multiplied in after the overlay.
     @location(9) light_color: vec4<f32>,
     @location(10) @interpolate(flat) weather_rect: vec4<f32>,
+    // The `GLINT_TEXTURING` sample for overlay 7 (item foil), or the model UV
+    // `ARMOR_ENTITY_GLINT_TEXTURING` scrolls for overlay 13 (armour).
+    @location(11) glint_uv: vec2<f32>,
+    // 1 drops the quad's back-facing pixels (Vertex::normal w = 1), like a culling render type.
+    @location(12) @interpolate(flat) cull: u32,
 }
 // Shipped light.glsl; normals are already transformed and RGBA8_SNORM packed.
 fn entity_light(normal: vec3<f32>, nether: bool) -> f32 {
@@ -92,7 +105,10 @@ fn entity_vertex(position: vec3<f32>, uv: vec2<f32>,
     // minecraft_mix_light: the vertex colour times the cardinal light only.
     var c = color;
     var back = c;
-    if normal.w != 0.0 {
+    // Normal w: 0 keeps the baked colour, +-127 shades by the normal, and a small positive 1
+    // keeps the baked colour but culls back faces (entitySolid models such as the decorated pot).
+    out.cull = select(0u, 1u, normal.w > 0.0 && normal.w < 0.5);
+    if abs(normal.w) >= 0.5 {
         c = vec4(c.rgb * entity_light(normal.xyz, globals.time.y != 0.0), c.a);
         back = select(c, vec4(back.rgb * entity_light(-normal.xyz, globals.time.y != 0.0), back.a), normal.w < 0.0);
     }
@@ -103,18 +119,23 @@ fn entity_vertex(position: vec3<f32>, uv: vec2<f32>,
     out.spherical = select(length(position), 0.0, overlay >= 2u && overlay <= 4u);
     out.cylindrical = select(max(length(position.xz), abs(position.y)), 0.0, overlay >= 2u && overlay <= 4u);
     out.overlay = overlay;
+    out.glint_uv = vec2(0.0);
     if overlay == 4u { out.spherical = length(position); }
     return out;
 }
 @vertex fn vs_entity(@location(0) position: vec3<f32>, @location(1) uv: vec2<f32>,
-    @location(2) overlay: u32, @location(3) color: vec4<f32>, @location(4) light: vec4<u32>, @location(5) normal: vec4<f32>) -> Out {
-    return entity_vertex(position, uv, overlay, color, light, normal);
+    @location(2) overlay: u32, @location(3) color: vec4<f32>, @location(4) light: vec4<u32>,
+    @location(5) normal: vec4<f32>, @location(6) glint_uv: vec2<f32>) -> Out {
+    var out = entity_vertex(position, uv, overlay, color, light, normal);
+    out.glint_uv = glint_uv;
+    return out;
 }
 // Retained bolt-local geometry, translated using the same f64 camera
 // subtraction as the former CPU path before adding each local f32 position.
+// The bolt offset is instance attribute 7: 6 is the entity vertex's glint UV.
 @vertex fn vs_lightning(@location(0) position: vec3<f32>, @location(1) uv: vec2<f32>,
     @location(2) overlay: u32, @location(3) color: vec4<f32>, @location(4) light: vec4<u32>, @location(5) normal: vec4<f32>,
-    @location(6) offset: vec3<f32>) -> Out {
+    @location(7) offset: vec3<f32>) -> Out {
     return entity_vertex(offset + position, uv, overlay, color, light, normal);
 }
 struct CloudInfo {
@@ -166,6 +187,27 @@ fn linear_fog(d: f32, start: f32, end: f32) -> f32 {
     if d >= end { return 1.0; }
     return (d - start) / (end - start);
 }
+// TextureTransform.setupGlintTexturing(0.16), ARMOR_ENTITY_GLINT_TEXTURING.
+// globals.time.w is (Util.getMillis() * glintSpeed * 8) modulo 330000, the
+// common period of both offsets.
+fn armor_glint_uv(model: vec2<f32>) -> vec2<f32> {
+    let ticks = globals.time.w;
+    let offset0 = (ticks % 110000.0) / 110000.0;
+    let offset1 = (ticks % 30000.0) / 30000.0;
+    let angle = 0.17453292;
+    let c = cos(angle);
+    let s = sin(angle);
+    let scaled = model * 0.16;
+    return vec2(scaled.x * c - scaled.y * s - offset0,
+                scaled.x * s + scaled.y * c + offset1);
+}
+// RenderPipelines.GLINT: the source colour is scaled by itself, so `GlintAlpha`
+// is squared along with the sample.
+fn glint_over(color: vec4<f32>, glint: vec4<f32>) -> vec4<f32> {
+    let alpha = globals.fog_ends.w;
+    let g = alpha * glint;
+    return vec4(color.rgb + g.rgb * g.rgb, max(color.a, alpha));
+}
 // CRUMBLING_UV_BEGIN
 fn crumbling_uv(uv: vec2<f32>, packed_origin: vec2<f32>, sprite_size: vec2<f32>, dimensions: vec2<u32>) -> vec2<f32> {
     let size = vec2<f32>(dimensions);
@@ -198,30 +240,75 @@ fn crumbling_uv(uv: vec2<f32>, packed_origin: vec2<f32>, sprite_size: vec2<f32>,
         // clouds.fsh: alpha fades out towards the cloud fog end.
         return vec4(color.rgb, color.a * (1.0 - linear_fog(in.spherical, 0.0, globals.fog_ends.y)));
     }
-    if color.a < 0.1 { discard; }
+    if color.a < 0.1 || (in.cull != 0u && !front) { discard; }
     // entity.fsh calculateFinalColor: the overlay (hurt red, TNT white) over the
     // lit texture, then the lightmap, then the glint and fog.
     color = vec4(mix(in.overlay_color.rgb, color.rgb, in.overlay_color.a), color.a);
     color *= in.light_color;
-    if in.overlay == 7u || in.overlay == 8u {
-        // Enchantment glint (overlay 7, 8 with the hurt tint): the purple
-        // enchanted_glint sheen drifting diagonally over the item's shape.
-        let px = in.uv * vec2<f32>(textureDimensions(atlas));
-        let t = globals.misc.y * 0.05;
-        let band = sin((px.x + px.y) * 0.9 - t * 6.0) * 0.5 + 0.5;
-        let band2 = sin((px.x - px.y) * 0.6 + t * 4.0) * 0.5 + 0.5;
-        let shimmer = pow(band * 0.6 + band2 * 0.4, 2.0);
-        let glint = vec3(0.50, 0.25, 0.80) * (0.25 + 0.75 * shimmer);
-        color = vec4(min(color.rgb + glint * 0.6, vec3(1.0)), color.a);
+    if in.overlay == 7u || in.overlay == 8u || in.overlay == 33u {
+        // 33: a translucent item with the glint.
+        // Enchantment glint: item.fsh's GLINT path, sampled from
+        // enchanted_glint_item at the `GLINT_TEXTURING` UV.
+        color = glint_over(color, textureSample(glint_tex, glint_sampler, in.glint_uv));
+    } else if in.overlay == 13u {
+        // Enchanted armour: enchanted_glint_armor at the scrolling model UV.
+        color = glint_over(
+            color,
+            textureSample(glint_armor_tex, glint_sampler, armor_glint_uv(in.glint_uv)),
+        );
     }
     let f = max(linear_fog(in.spherical, globals.fog.x, globals.fog.y),
                 linear_fog(in.cylindrical, globals.fog.z, globals.fog.w));
     return vec4(mix(color.rgb, globals.fog_color.rgb, f * globals.fog_color.a), color.a);
 }
 
+// rendertype_outline.fsh: the vertex colour (the team colour; outline vertices carry no
+// normal, so no cardinal light) wherever the texture is not fully clear.
+// rendertype_entity_shadow.fsh: the shadow texture times the vertex colour,
+// then fog, with no alpha cutout, so a faint shadow in dim light still draws.
+@fragment fn fs_entity_shadow(in: Out) -> @location(0) vec4<f32> {
+    var color = textureSample(atlas, atlas_sampler, in.uv) * in.color;
+    color *= in.light_color;
+    let f = max(linear_fog(in.spherical, globals.fog.x, globals.fog.y),
+                linear_fog(in.cylindrical, globals.fog.z, globals.fog.w));
+    return vec4(mix(color.rgb, globals.fog_color.rgb, f * globals.fog_color.a), color.a);
+}
+
+@fragment fn fs_outline(in: Out) -> @location(0) vec4<f32> {
+    if textureSample(atlas, atlas_sampler, in.uv).a == 0.0 { discard; }
+    return vec4(in.color.rgb, 1.0);
+}
+
+fn celestial_color(in: Out) -> vec4<f32> {
+    return textureSample(atlas, atlas_sampler, in.uv) * in.color * in.light_color;
+}
 @fragment fn fs_celestial(in: Out) -> @location(0) vec4<f32> {
-    let color = textureSample(atlas, atlas_sampler, in.uv) * in.color * in.light_color;
-    return color;
+    return celestial_color(in);
+}
+
+// The sky's celestial pass (sun, moon, the End sky): fs_celestial's light,
+// premultiplied for an additive (one, one) blend, and as alpha how much of it
+// the texel adds, which the blend takes off the frame's alpha. HDR output
+// (hdr.wgsl) lifts only where that left it low: the sun's and moon's discs, not
+// the dark rest of their quads or the dim End sky.
+@fragment fn fs_sky_celestial(in: Out) -> @location(0) vec4<f32> {
+    let color = celestial_color(in);
+    let added = color.rgb * color.a;
+    return vec4(added, smoothstep(0.1, 0.3, max(added.r, max(added.g, added.b))));
+}
+
+// RenderPipelines.ENERGY_SWIRL (entity.fsh with EMISSIVE and NO_OVERLAY): the sprite, scrolled by
+// the UV and repeated within itself, times the layer colour 0xFF808080, unlit; the pipeline adds
+// it to the frame. The light bytes carry the sprite's origin and the colour bytes its size, both
+// as breaking::stage_light packs them.
+@fragment fn fs_energy_swirl(in: Out) -> @location(0) vec4<f32> {
+    let bytes = round(in.color * 255.0);
+    let size = vec2(bytes.x + bytes.y * 256.0, bytes.z + bytes.w * 256.0) / 65535.0;
+    let color = textureSample(atlas, atlas_sampler, crumbling_uv(in.uv, in.wrap, size, textureDimensions(atlas)));
+    if color.a < 0.1 { discard; }
+    let f = max(linear_fog(in.spherical, globals.fog.x, globals.fog.y),
+                linear_fog(in.cylindrical, globals.fog.z, globals.fog.w));
+    return vec4(mix(color.rgb * (128.0 / 255.0), globals.fog_color.rgb, f * globals.fog_color.a), color.a);
 }
 
 // RenderPipelines.WATER_MASK: depth only (the pipeline masks the colour off).

crates/horizon-client-render/src/fog.rs

@@ -203,6 +203,13 @@ pub struct FogInputs<'a> {
     /// `BossHealthOverlay.shouldCreateWorldFog`: a boss bar with
     /// `createWorldFog` is shown (the Ender Dragon's).
     pub boss_world_fog: bool,
+    /// The camera entity is a spectator (`LavaFogEnvironment`).
+    pub spectator: bool,
+    /// The camera entity has Fire Resistance (`LavaFogEnvironment`).
+    pub fire_resistance: bool,
+    /// `GameRenderer.nightVisionScale` while Night Vision is on without
+    /// Darkness, else 0 (`FogRenderer.computeFogColor`'s brightenFactor).
+    pub night_vision: f32,
 }
 
 /// `FogRenderer.setupFog` + `computeFogColor`.
@@ -272,7 +279,11 @@ pub fn setup_fog(tables: &FogTables, state: &FogState, input: &FogInputs) -> Fog
         color[1] += (color[1] * 0.6 - color[1]) * t;
         color[2] += (color[2] * 0.6 - color[2]) * t;
     }
-    let brighten = if eye_in_water { water_vision } else { 0.0 };
+    let brighten = if eye_in_water {
+        water_vision
+    } else {
+        input.night_vision
+    };
     if color.iter().all(|&c| c != 0.0) {
         let scale = 1.0 / color[0].max(color[1]).max(color[2]);
         color = color.map(|c| c + (c * scale - c) * brighten);
@@ -288,10 +299,16 @@ pub fn setup_fog(tables: &FogTables, state: &FogState, input: &FogInputs) -> Fog
     };
     match input.fog_type {
         FogType::Lava => {
-            fog.environmental_start = 0.25;
-            fog.environmental_end = 1.0;
-            fog.sky_end = 1.0;
-            fog.cloud_end = 1.0;
+            // LavaFogEnvironment.setupFog.
+            (fog.environmental_start, fog.environmental_end) = if input.spectator {
+                (-8.0, rd * 0.5)
+            } else if input.fire_resistance {
+                (0.0, 5.0)
+            } else {
+                (0.25, 1.0)
+            };
+            fog.sky_end = fog.environmental_end;
+            fog.cloud_end = fog.environmental_end;
         }
         FogType::PowderSnow => {
             fog.environmental_start = 0.0;
@@ -362,6 +379,22 @@ pub fn setup_fog(tables: &FogTables, state: &FogState, input: &FogInputs) -> Fog
     }
     fog
 }
+/// Horizon's Fog option turned off (`horizon-graphics.txt` `fog:false`):
+/// no distance fog, in any dimension: the dimension's and biome's own fog
+/// (`visual/fog_start_distance`, `fog_end_distance`: the Nether's ends at 96
+/// blocks) and the render-distance fog. The fog of the fluid or powder snow
+/// the camera is in, blindness, darkness and a boss's world fog keep their
+/// limits. Vanilla has no such option.
+pub fn clear_distance_fog(fog: &mut FogData, input: &FogInputs) {
+    if input.fog_type == FogType::Atmospheric
+        && input.darkness.is_none()
+        && !input.boss_world_fog
+        && input.blindness.is_none()
+    {
+        (fog.render_distance_start, fog.render_distance_end) = (1e9, 2e9);
+        (fog.environmental_start, fog.environmental_end) = (1e9, 2e9);
+    }
+}
 /// `AtmosphericFogEnvironment.updateRainFogState`.
 pub fn update_rain_fog(
     state: &mut FogState,
@@ -405,6 +438,9 @@ mod tests {
             darkness: None,
             darken_world: 0.0,
             boss_world_fog: false,
+            spectator: false,
+            fire_resistance: false,
+            night_vision: 0.0,
         }
     }
     #[test]
@@ -432,6 +468,56 @@ mod tests {
         assert_eq!(water.environmental_start, -8.0);
     }
     #[test]
+    fn fog_off_clears_the_nether_fog_too() {
+        // The Nether's visual/fog_start_distance and fog_end_distance (10, 96)
+        // end before the render distance; the Fog option still clears them.
+        let nether = Sky {
+            fog_start: 10.0,
+            fog_end: 96.0,
+            ..Sky::default()
+        };
+        let tables = FogTables {
+            water_fog_end: vec![1.0],
+        };
+        let mut input = inputs(&nether);
+        input.skybox = false;
+        let mut fog = setup_fog(&tables, &FogState::default(), &input);
+        assert_eq!(fog.environmental_end, 96.0);
+        clear_distance_fog(&mut fog, &input);
+        assert!(fog.environmental_start >= 1e9 && fog.render_distance_start >= 1e9);
+    }
+    #[test]
+    fn fog_off_keeps_fluid_and_effect_fog() {
+        let sky = Sky {
+            fog_start: 10.0,
+            fog_end: 96.0,
+            ..Sky::default()
+        };
+        let tables = FogTables {
+            water_fog_end: vec![1.0],
+        };
+        let kept = |input: &FogInputs| {
+            let mut fog = setup_fog(&tables, &FogState::default(), input);
+            let before = fog;
+            clear_distance_fog(&mut fog, input);
+            fog == before
+        };
+        for fog_type in [FogType::Lava, FogType::PowderSnow, FogType::Water] {
+            let mut input = inputs(&sky);
+            input.fog_type = fog_type;
+            assert!(kept(&input), "{fog_type:?}");
+        }
+        let mut input = inputs(&sky);
+        input.blindness = Some((100, false));
+        assert!(kept(&input));
+        let mut input = inputs(&sky);
+        input.darkness = Some(0.5);
+        assert!(kept(&input));
+        let mut input = inputs(&sky);
+        input.boss_world_fog = true;
+        assert!(kept(&input));
+    }
+    #[test]
     fn boss_darkening_dims_fog_color() {
         // FogRenderer.computeFogColor: lerp toward 70/60/60% of each channel.
         let sky = Sky {

crates/horizon-client-render/src/font.rs

@@ -8,7 +8,7 @@
 //! offsets), styled drawing and StringSplitter-style line wrapping.
 use crate::{
     hud::Rect,
-    text::{Style, Text},
+    text::{Span, Style, Text, legacy_format},
     zip::Zip,
 };
 use ab_glyph::{Font as _, ScaleFont as _};
@@ -130,6 +130,8 @@ pub struct Font {
     atlas: (u32, u32),
     region: (u32, u32),
     cache: RefCell<Cache>,
+    /// Set anew for each font and each `reset_cache` (see `epoch`).
+    generation: std::cell::Cell<u64>,
     /// "Force Unicode Font": the `uniform` filter option.
     pub uniform: bool,
     /// "Japanese Glyph Variants": the `jp` filter option.
@@ -559,6 +561,11 @@ impl Region {
         Some((ax, ay))
     }
 }
+/// A value no font has had yet (`Font::epoch`).
+fn next_generation() -> u64 {
+    static NEXT: std::sync::atomic::AtomicU64 = std::sync::atomic::AtomicU64::new(0);
+    NEXT.fetch_add(1, std::sync::atomic::Ordering::Relaxed)
+}
 impl Font {
     /// Build from the atlas holding the bitmap font sheets (`sprites`, of
     /// `atlas` size) with `region` the reserved rows.
@@ -603,6 +610,7 @@ impl Font {
                         .map_or(0, |d| d.as_nanos() as i64),
                 ),
             }),
+            generation: std::cell::Cell::new(next_generation()),
             uniform: false,
             japanese: false,
         };
@@ -661,6 +669,13 @@ impl Font {
         }
         cache.region.cursor = (0, 0);
         cache.region.row = 0;
+        self.generation.set(next_generation());
+    }
+    /// Changes whenever a glyph may come out different: another font, a
+    /// cache reset (glyphs move in the atlas) or other font options. Text laid
+    /// out under one epoch can be kept until it changes.
+    pub fn epoch(&self) -> u64 {
+        self.generation.get() << 2 | u64::from(self.uniform) << 1 | u64::from(self.japanese)
     }
     /// The glyph for a character in the default font (FontSet.getGlyph).
     pub fn glyph(&self, c: char) -> Glyph {
@@ -889,12 +904,17 @@ impl Font {
         if s.contains('§') {
             return self.width_text(&Text::legacy(s));
         }
-        s.chars().map(|c| self.glyph(c).advance).sum::<f32>().ceil()
+        crate::bidi::visual_str(s)
+            .chars()
+            .map(|c| self.glyph(c).advance)
+            .sum::<f32>()
+            .ceil()
     }
     /// Font.width of a component: `§` codes in the spans are formatting,
-    /// not glyphs.
+    /// not glyphs. Right-to-left text is measured as it is drawn, shaped.
     pub fn width_text(&self, t: &Text) -> f32 {
-        t.resolved()
+        let t = t.resolved();
+        crate::bidi::visual(&t)
             .chars()
             .map(|(c, s)| self.advance(c, s))
             .sum::<f32>()
@@ -946,6 +966,83 @@ impl Font {
         }
         out
     }
+    /// `Font.split`: `StringSplitter.splitLines(text, width, Style.EMPTY)` over
+    /// the text's parts with their `§` codes in. A code styles what follows
+    /// (`§r` back to no style while measuring), and the part a line breaks in
+    /// goes on in the style at the break. Lines keep their codes for drawing.
+    pub fn split_formatted(&self, t: &Text, max_width: f32) -> Vec<Text> {
+        let max_width = max_width.max(1.0);
+        let mut parts: Vec<(Vec<char>, Style)> = t
+            .spans
+            .iter()
+            .filter(|s| !s.text.is_empty())
+            .map(|s| (s.text.chars().collect(), s.style.clone()))
+            .collect();
+        let mut flat: Vec<char> = parts.iter().flat_map(|p| p.0.iter().copied()).collect();
+        let mut out = Vec::new();
+        let mut force_new_line = false;
+        // One LineBreakFinder per line, over the parts left.
+        while let Some((at, split_style)) = self.line_break(&parts, max_width) {
+            let tail = flat[at];
+            let new_line = tail == '\n';
+            let skip = usize::from(new_line || tail == ' ');
+            force_new_line = new_line;
+            out.push(split_at(&mut parts, at, skip, &split_style));
+            flat.drain(..at + skip);
+        }
+        if !parts.is_empty() {
+            let mut rest = Text::default();
+            rest.spans = parts
+                .into_iter()
+                .map(|(text, style)| Span {
+                    text: text.into_iter().collect(),
+                    style,
+                })
+                .collect();
+            out.push(rest);
+        } else if force_new_line {
+            out.push(Text::empty());
+        }
+        out
+    }
+    /// `StringSplitter.LineBreakFinder` fed by `StringDecomposer.iterateFormatted`:
+    /// where the parts break (a character index) and the style there.
+    fn line_break(&self, parts: &[(Vec<char>, Style)], max_width: f32) -> Option<(usize, Style)> {
+        let (mut width, mut had_visible, mut last_space) = (0.0f32, false, None);
+        let mut offset = 0;
+        for (contents, part_style) in parts {
+            let mut style = part_style.clone();
+            let mut i = 0;
+            while i < contents.len() {
+                let c = contents[i];
+                if c == '§' {
+                    // A `§` that ends its part ends only that part.
+                    let Some(&code) = contents.get(i + 1) else {
+                        break;
+                    };
+                    style = legacy_format(&style, code, &Style::default());
+                    i += 2;
+                    continue;
+                }
+                let at = offset + i;
+                if c == '\n' {
+                    return Some((at, style));
+                }
+                if c == ' ' {
+                    last_space = Some((at, style.clone()));
+                }
+                let advance = self.advance(c, &style);
+                width += advance;
+                if had_visible && width > max_width {
+                    return Some(last_space.unwrap_or((at, style)));
+                }
+                had_visible |= advance != 0.0;
+                i += 1;
+            }
+            offset += contents.len();
+        }
+        None
+    }
     /// `ComponentRenderUtils.wrapComponents`: the split lines, wrapped ones
     /// indented by an unstyled space; one empty line for empty text.
     pub fn wrap_components(&self, t: &Text, max_width: i32) -> Vec<Text> {
@@ -1039,6 +1136,47 @@ impl Font {
     }
 }
 
+/// `StringSplitter.FlatComponents.splitAt`: the parts before `at` as a line,
+/// `skip` characters dropped, and the part it ends in restyled as `style`.
+fn split_at(parts: &mut Vec<(Vec<char>, Style)>, at: usize, skip: usize, style: &Style) -> Text {
+    let mut line = Text::default();
+    let mut push = |text: &[char], style: &Style| {
+        line.spans.push(Span {
+            text: text.iter().collect(),
+            style: style.clone(),
+        })
+    };
+    // Each part done is removed, so the one at hand is always the first.
+    let (mut position, mut in_skip) = (at, false);
+    while let Some((text, part_style)) = parts.first() {
+        let size = text.len();
+        if !in_skip {
+            if position > size {
+                push(text, part_style);
+                parts.remove(0);
+                position -= size;
+                continue;
+            }
+            if position > 0 {
+                push(&text[..position], part_style);
+            }
+            position += skip;
+            in_skip = true;
+        }
+        if position <= size {
+            if position == size {
+                parts.remove(0);
+            } else {
+                parts[0] = (text[position..].to_vec(), style.clone());
+            }
+            break;
+        }
+        parts.remove(0);
+        position -= size;
+    }
+    line
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -1201,6 +1339,37 @@ mod tests {
         assert!(!font.take_patches().is_empty());
     }
 
+    /// StringDecomposer.iterateFormatted: a `§` that ends a part stops that
+    /// part only; the next part is still measured and can break.
+    #[test]
+    fn a_section_sign_ending_a_part_still_breaks_the_next() {
+        let sheet = png(16, 8, |x, _| x < 2);
+        let default = br#"{"providers":[{"type":"space","advances":{" ":4}},{"type":"bitmap","file":"minecraft:font/a.png","ascent":7,"chars":["ab"]}]}"#;
+        let root = root(
+            "section-sign",
+            &[
+                ("assets/minecraft/font/default.json", default),
+                ("assets/minecraft/textures/font/a.png", &sheet),
+            ],
+        );
+        let font = load(&root);
+        let _ = std::fs::remove_dir_all(&root);
+        let mut text = Text::default();
+        text.spans = ["a§", "a a"]
+            .map(|part| Span {
+                text: part.into(),
+                style: Style::default(),
+            })
+            .into();
+        // 3 + 3 + 4 + 3 is past 12: the line breaks at the space.
+        let lines: Vec<String> = font
+            .split_formatted(&text, 12.0)
+            .iter()
+            .map(Text::plain)
+            .collect();
+        assert_eq!(lines, ["a§a", "a"]);
+    }
+
     /// A renderer rebuilt over the same font (the loading screen's handoff)
     /// makes its atlas texture from the textures alone, so the glyphs it had
     /// rasterized into the previous texture must be placed into the new one.

crates/horizon-client-render/src/gfx/animate.rs

@@ -103,10 +103,11 @@ impl SpriteAnimator {
         let mut counts: Vec<usize> = Vec::new();
         let mut sprites = Vec::with_capacity(animations.len());
         for animation in animations {
-            let chains: Vec<_> = (0..animation.frame_count())
-                .map(|frame| source_chain(animation.pixels(frame), size, settings, animation.layer))
+            let pixels: Vec<_> = (0..animation.frame_count())
+                .map(|frame| animation.pixels(frame))
                 .collect();
-            let bytes: u64 = chains.iter().map(|(chain, _)| chain.len() as u64).sum();
+            let (chains, edge) = source_chains(&pixels, size, settings, animation.layer);
+            let bytes: u64 = chains.iter().map(|chain| chain.len() as u64).sum();
             if bytes > limit {
                 log::warn!(
                     "Horizon: layer {}'s animation ({bytes} bytes) does not fit in a storage buffer; it stays still",
@@ -124,7 +125,7 @@ impl SpriteAnimator {
             let data = &mut frames[buffer];
             let offsets = chains
                 .iter()
-                .map(|(chain, _)| {
+                .map(|chain| {
                     let offset = (data.len() / 4) as u32;
                     data.extend_from_slice(chain);
                     offset
@@ -142,7 +143,7 @@ impl SpriteAnimator {
                 shown: None,
                 layer: animation.layer % split,
                 frames: offsets,
-                edge: chains[0].1,
+                edge,
                 group,
             });
         }
@@ -424,15 +425,63 @@ fn mix_level(frames: &[u8], [_, current, next, millis, edge]: [u32; 5], width: u
 /// array's size from its own size's chain, its first level repeated into the
 /// larger levels: that chain, which the shader repeats. Any other sprite: its
 /// chain at the array's size.
+#[cfg(test)]
 fn source_chain(pixels: &[u8], size: u32, settings: &[Settings], layer: u32) -> (Vec<u8>, u32) {
-    let native = settings.get(layer as usize).map_or(0, |s| s.native_size);
-    let edge = if native.is_power_of_two() && native < size {
-        native
+    let (mut chains, edge) = source_chains(&[pixels], size, settings, layer);
+    (chains.swap_remove(0), edge)
+}
+
+/// Every frame's chain, laid out as one frame's `source_chain`, but mipmapped as
+/// vanilla's `SpriteContents.increaseMipLevel` does: over the whole animation
+/// sheet (the frames stacked), so `solidify` and the alpha-to-coverage scale
+/// of each level are the sheet's, not each frame's. A frame alone has a
+/// single texel square at its 2x2 level, and its coverage scale could round
+/// a whole far frame transparent (kelp blinking out at distance).
+fn source_chains(
+    frames: &[&[u8]],
+    size: u32,
+    settings: &[Settings],
+    layer: u32,
+) -> (Vec<Vec<u8>>, u32) {
+    let s = settings.get(layer as usize).copied().unwrap_or_default();
+    let edge = if s.native_size.is_power_of_two() && s.native_size < size {
+        s.native_size
     } else {
         size
     };
-    let frame = crate::sprites::resample(pixels, size, edge);
-    (super::mip_chain(&frame, edge, settings, layer, 1).0, edge)
+    let mut sheet = crate::mipmap::Image {
+        width: edge,
+        height: edge * frames.len() as u32,
+        pixels: Vec::with_capacity((edge * edge) as usize * frames.len()),
+    };
+    for frame in frames {
+        let frame = crate::sprites::resample(frame, size, edge);
+        sheet.pixels.extend_from_slice(frame.as_chunks::<4>().0);
+    }
+    let has_transparent = s.has_transparent || sheet.pixels.iter().any(|p| p[3] == 0);
+    let levels = crate::mipmap::generate(
+        sheet,
+        edge.trailing_zeros(),
+        Settings {
+            has_transparent,
+            ..s
+        },
+    );
+    let chains = (0..frames.len())
+        .map(|frame| {
+            let mut chain = Vec::new();
+            for level in &levels {
+                let texels = (level.width * level.width) as usize;
+                chain.extend(
+                    level.pixels[frame * texels..(frame + 1) * texels]
+                        .iter()
+                        .flatten(),
+                );
+            }
+            chain
+        })
+        .collect();
+    (chains, edge)
 }
 
 #[cfg(test)]
@@ -572,6 +621,63 @@ mod tests {
         }
     }
 
+    #[test]
+    fn kelp_frames_share_the_sheet_mips() {
+        let root = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
+            .join("../../.local/horizon-client")
+            .join(horizon_core::VANILLA_VERSION);
+        if !root
+            .join("assets/minecraft/textures/block/kelp.png")
+            .exists()
+        {
+            return;
+        }
+        let mut sprites = crate::sprites::Sprites::default();
+        for name in ["kelp", "kelp_plant", "seagrass", "tall_seagrass_top"] {
+            sprites
+                .insert(&root, &format!("minecraft:block/{name}"))
+                .unwrap();
+        }
+        sprites.finish();
+        // A level drawn nowhere: no texel passes the cutout's alpha test.
+        let blank = |chain: &[u8], edge: u32| {
+            let mut start = 0;
+            let mut level = edge;
+            let mut blank = Vec::new();
+            while level > 0 {
+                let bytes = (level * level * 4) as usize;
+                let texels = &chain[start..start + bytes];
+                blank.push(texels.as_chunks::<4>().0.iter().all(|p| p[3] < 128));
+                start += bytes;
+                level >>= 1;
+            }
+            blank
+        };
+        let mut blinked = 0;
+        for animation in &sprites.animations {
+            let size = sprites.size;
+            let pixels: Vec<_> = (0..animation.frame_count())
+                .map(|f| animation.pixels(f))
+                .collect();
+            let (chains, edge) = source_chains(&pixels, size, &sprites.mips, animation.layer);
+            for (frame, chain) in chains.iter().enumerate() {
+                // The 1x1 level has no texel square to measure coverage on
+                // (vanilla leaves it unscaled); every larger level shows.
+                let levels = blank(chain, edge);
+                assert!(
+                    !levels[..levels.len() - 1].contains(&true),
+                    "layer {} frame {frame}: {levels:?}",
+                    animation.layer
+                );
+                let (alone, _) = source_chain(pixels[frame], size, &sprites.mips, animation.layer);
+                let alone = blank(&alone, edge);
+                blinked += usize::from(alone[..alone.len() - 1].contains(&true));
+            }
+        }
+        // Mipmapped frame by frame, some kelp frames vanished at the 2x2 level.
+        assert!(blinked > 0);
+    }
+
     #[test]
     fn rounding_matches_f32_mix_but_for_exact_halves() {
         // The CPU blend this replaced: f32 mix, then rounded. They differ
@@ -730,8 +836,11 @@ mod tests {
             queue.submit([encoder.finish()]);
             for animation in &animations {
                 let blend = animation.blend(tick);
-                let chain = |f| source_chain(animation.pixels(f), size, &mips, animation.layer);
-                let ((current, edge), (next, _)) = (chain(blend.frame), chain(blend.next));
+                let pixels: Vec<_> = (0..animation.frame_count())
+                    .map(|f| animation.pixels(f))
+                    .collect();
+                let (chains, edge) = source_chains(&pixels, size, &mips, animation.layer);
+                let (current, next) = (&chains[blend.frame], &chains[blend.next]);
                 let layers = read_back(
                     &device,
                     &queue,
@@ -739,7 +848,7 @@ mod tests {
                 );
                 assert_eq!(
                     layers[(animation.layer % split) as usize],
-                    reference(&current, &next, blend.millis, edge, size),
+                    reference(current, next, blend.millis, edge, size),
                     "layer {} at tick {tick}",
                     animation.layer
                 );