Merge branch 'pr/2570' into union/pt2-a

🤖 Agent: Ludovic's decision 10-29 (native mods on when one is installed, notice once). Diff reviewed; verify green; build matrix 40848959744 green on Windows, macOS and Linux.

.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

@@ -6,3 +6,4 @@
 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/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

@@ -1,11 +1,12 @@
 name: nightly build
 run-name: nightly build${{ inputs.request && format(' (request {0})', inputs.request) || '' }}
-# The opt-in Nightly channel (docs/release-flow.md "Nightly"; Ludovic, 2026-10-27). Once a night, and when a trusted
+# The Nightly, the only build Horizon ships since 2026-10-28 (docs/release-flow.md "Nightly"; Ludovic). When the batch
+# train decides (release.yml, with the commit as `base`), once a night, and when a trusted
 # reviewer asks (`/nightly 2640 2642`, nightly-command.yml), it builds main plus the pull requests the reviewers
-# picked, merged in order (tools/ci/nightly_set.py). With none picked, it builds the newest union branch on origin
-# (union/<agent>-<name>: main plus pull requests the contribution gate proved together), or main when no union is
-# newer. It publishes the result as the `nightly` pre-release. Launchers install it only for players who turn Nightly
-# on. The previous nightly stays a week as nightly-<date>.
+# picked, merged in order (tools/ci/nightly_set.py), or main alone with none picked. Main is its newest commit where
+# checks and parity-main passed (or the `base` input), as for a release, and no Nightly is published while a
+# release-blocker is open. It publishes the result as the `nightly` pre-release, which every launcher and
+# `horizon-server update` install. The previous nightly stays a week as nightly-<date>.
 #
 # Why the signing key never meets the pull requests' code:
 # - `pick` merges the picked heads onto main with `git merge-tree --write-tree`: git objects only, no working tree,
@@ -13,11 +14,11 @@ run-name: nightly build${{ inputs.request && format(' (request {0})', inputs.req
 #   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. The union's own .github/ is never read.
+#   `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 (or the union) with no secrets: its token reads contents only and
+# - `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
@@ -25,6 +26,9 @@ run-name: nightly build${{ inputs.request && format(' (request {0})', inputs.req
 #   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
@@ -53,6 +57,14 @@ on:
         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:
@@ -68,6 +80,7 @@ jobs:
       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 }}
@@ -76,6 +89,7 @@ jobs:
       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
@@ -92,6 +106,8 @@ jobs:
           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"
@@ -103,6 +119,18 @@ jobs:
           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
@@ -144,7 +172,7 @@ jobs:
           EPHEMERAL: ${{ needs.pick.outputs.dry_run == 'true' && 'yes' || '' }}
         run: |
           bash tools/ci/sign_release.sh nightly dist/horizon-linux-x86_64.tar.gz dist/horizon-windows-x64.zip \
-            dist/horizon-macos-arm64.zip dist/horizon-server-linux-x86_64.tar.gz
+            dist/horizon-macos-arm64.zip dist/horizon-server-linux-x86_64.tar.gz dist/horizon-source.tar.gz
       - uses: actions/upload-artifact@v4
         with:
           name: signature
@@ -164,6 +192,7 @@ jobs:
     timeout-minutes: 15
     permissions:
       contents: write
+      issues: read          # the open release-blocker issues (gate)
     steps:
       - uses: actions/checkout@v4
         with:
@@ -178,27 +207,39 @@ jobs:
         run: |
           key=(); [[ -n "$EPHEMERAL" ]] && key=(--key "$(cat dist/ephemeral.pub)")
           cargo run --locked --quiet -p horizon-release-sign -- verify --tag nightly --publishing "${key[@]}" dist
-      - name: The smoke test drew a world
-        # No release-blocker check: a nightly is how blockers get tested.
-        run: python3 tools/release_train.py gate --kind game --smoke dist/smoke-test.json
+      - 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: ${{ needs.pick.outputs.source_tag }}
         run: |
           set -euo pipefail
           python3 tools/ci/nightly.py rotate
           signature=(); [[ -f dist/SHA256SUMS.sig ]] && signature=(dist/SHA256SUMS.sig)
-          # A pre-release, never GitHub's latest: launchers on the release channel never see it.
+          # A pre-release, never GitHub's latest: the latest stays the last vX.Y.Z, which launchers and servers from
+          # before the Nightly-only switch keep (they don't read Nightlies).
           gh release create nightly --prerelease --latest=false --target "$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'
@@ -230,7 +271,7 @@ jobs:
           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 with Nightly on install it at their next start."
+            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

.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).
@@ -28,17 +21,19 @@ 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:
   # 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
@@ -54,9 +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
@@ -76,127 +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
 
-  build:
+  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'
-    # Every platform's archive, and macOS's smoke test (game-build.yml).
-    uses: ./.github/workflows/game-build.yml
-    with:
-      ref: ${{ needs.decide.outputs.head }}
-      version: ${{ needs.decide.outputs.version }}
-      trusted: true  # main: the release runner, the release cache, no shared sccache
-
-  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"

AGENTS.md

@@ -35,10 +35,12 @@ Game workspace (root `Cargo.toml`); `launcher/` and `crates/horizon-telemetry-se
 
 | Crate | Owns |
 |---|---|
-| `horizon-client` | The game: a lib (`src/lib.rs`, ~170 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` |
@@ -98,6 +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`
@@ -109,12 +114,13 @@ 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/`) |
@@ -130,7 +136,7 @@ python3 tools/agent_control_e2e.py         # horizon-ctl / MCP end to end
 | 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`, `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`; 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` |
+| 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`; `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)) |

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).
 

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"
@@ -1370,16 +1376,16 @@ 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",
@@ -1398,6 +1404,7 @@ dependencies = [
  "log",
  "miniz_oxide 0.8.9",
  "naga",
+ "open",
  "png",
  "pollster",
  "rustix 1.1.5",
@@ -1405,7 +1412,6 @@ dependencies = [
  "serde_json",
  "sha1",
  "sha2",
- "symphonia",
  "unicode-bidi",
  "ureq",
  "wgpu",
@@ -1422,6 +1428,60 @@ dependencies = [
  "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",
+ "sha2",
+ "symphonia",
+ "unicode-bidi",
+ "ureq",
+ "wgpu",
+ "winit",
+ "zip",
+]
+
 [[package]]
 name = "horizon-command"
 version = "0.1.0"
@@ -1865,6 +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"
@@ -2679,6 +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"
@@ -3194,9 +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",
@@ -4374,14 +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

@@ -8,6 +8,8 @@ members = [
     "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",
@@ -60,8 +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

@@ -1,5 +1,5 @@
 <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">
@@ -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/horizon-rust/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** 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)); 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 on Linux and 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>
@@ -48,7 +48,7 @@ The [documentation](https://playhorizon.dev/docs/) covers each of these.
 - **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 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 mod system (Rust compiled to WebAssembly). Java mod jars do not run. See [Mods and data packs](https://playhorizon.dev/docs/mods).
+- **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:
 
@@ -93,7 +93,7 @@ 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.
@@ -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 |

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.
 
@@ -104,37 +104,49 @@ 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/horizon-rust/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/horizon-rust/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/horizon-rust/horizon/issues/1816)) and, for server mods, scripted server events ([#1837](https://github.com/horizon-rust/horizon/issues/1837)); the content template and the guides are merged ([#1859](https://github.com/horizon-rust/horizon/issues/1859), [#1810](https://github.com/horizon-rust/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>
 
@@ -244,6 +256,20 @@ Horizon's own way to make shader packs, with tools to write and test them. Every
 
 </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>
+
 ### Horizon extras
 
 #### Discord Rich Presence
@@ -268,6 +294,16 @@ A review of the whole tree: dead code and stubs removed ([#1432](https://github.
 
 </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>
+
 ## Next
 
 ### Performance
@@ -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>
 
@@ -468,16 +514,6 @@ Block entities and menus: ticking machines with slots, server menu logic and the
 
 </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').
-
-</details>
-
 ### Gameplay parity
 
 #### Pistons push players and mobs
@@ -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/horizon-rust/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>
 
@@ -708,6 +742,18 @@ Issue [#1270](https://github.com/horizon-rust/horizon/issues/1270) asks for Ely.
 
 </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>
+
 #### Online-mode checks for Play with Friends
 
 Friends who join through an invite code could prove who they are with their Microsoft account, as on online-mode servers.
@@ -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>
 
@@ -784,6 +842,16 @@ 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.
@@ -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>
 
@@ -862,6 +930,18 @@ Issue [#1709](https://github.com/horizon-rust/horizon/issues/1709): aarch64 buil
 
 </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>
+
 #### Android, iOS and the browser
 
 Versions of Horizon for Android, iOS and web browsers. Nothing official yet; contributors have started the first pieces.
@@ -968,6 +1048,7 @@ Armour and tools in End city chests should come enchanted, as in vanilla.
 
 ## Recently shipped
 
+- **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)

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),

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

@@ -494,7 +494,11 @@ pub fn canonical(tag: &Tag) -> Option<Tag> {
                     _ => string("minecraft:air"),
                 },
             );
-            f.put("facing", Tag::Int(int(tag.get("facing")).unwrap_or(0)));
+            // Direction.LEGACY_ID_CODEC: the 3D data value as a byte.
+            f.put(
+                "facing",
+                Tag::Byte(int(tag.get("facing")).unwrap_or(0) as i8),
+            );
             f.float("progress", 0.0);
             f.flag("extending", false);
             f.flag("source", false);
@@ -873,6 +877,23 @@ mod tests {
         );
     }
 
+    /// `PistonMovingBlockEntity.saveAdditional`: `facing` through
+    /// `Direction.LEGACY_ID_CODEC` (a byte), `progress` a float.
+    #[test]
+    fn moving_piston_fields_match_vanilla() {
+        let out = canon(
+            "{id:\"minecraft:piston\",x:1,y:2,z:3,blockState:{Name:\"minecraft:stone\"},\
+             facing:5,progress:0.5f,extending:1b,source:0b}",
+        );
+        assert_eq!(out.get("facing"), Some(&Tag::Byte(5)));
+        assert_eq!(out.get("progress"), Some(&f32_tag(0.5)));
+        assert_eq!(out.get("extending"), Some(&Tag::Byte(1)));
+        assert_eq!(out.get("source"), Some(&Tag::Byte(0)));
+        let fresh = canon("{id:\"minecraft:piston\",x:1,y:2,z:3}");
+        assert_eq!(fresh.get("facing"), Some(&Tag::Byte(0)));
+        assert_eq!(fresh.get("blockState"), Some(&string("minecraft:air")));
+    }
+
     #[test]
     fn loot_table_replaces_items_and_zero_seed_is_omitted() {
         let out = canon(

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

@@ -195,6 +195,11 @@ fn object_style(o: &serde_json::Map<String, Value>) -> Style {
             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,
         };
     }

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

@@ -16,3 +16,20 @@ pub fn parse_identifier(raw: &str) -> Option<String> {
     });
     (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/lang.rs

@@ -40,6 +40,10 @@ 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()]
@@ -68,6 +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()
@@ -190,7 +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(
@@ -284,4 +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/nbt_value.rs

@@ -22,3 +22,11 @@ pub fn number(tag: Option<&Tag>) -> Option<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/registries.rs

@@ -54,6 +54,9 @@ pub struct Registries {
     pub function_tags: Vec<String>,
     /// The block the source is looking at (relevant coordinates).
     pub target_block: Option<[i32; 3]>,
+    /// `ClientSuggestionProvider.getSelectedEntities`: the UUID of the
+    /// entity under the crosshair (`Entity.getStringUUID`), if any.
+    pub selected_entities: Vec<String>,
     /// 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>,

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

@@ -50,6 +50,9 @@ pub enum ClickEvent {
     /// `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),
@@ -557,6 +560,11 @@ fn style_json(style: &Style) -> Vec<(String, 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));

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

@@ -145,6 +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),
@@ -157,6 +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),
@@ -188,6 +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),

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,

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

@@ -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/biome.rs

@@ -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,
@@ -150,12 +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()

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

@@ -26,6 +26,7 @@
 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

@@ -97,6 +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)
@@ -587,6 +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(
@@ -747,6 +769,9 @@ pub struct Scene<'a> {
     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 {
@@ -758,7 +783,30 @@ 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"),
@@ -888,6 +936,7 @@ impl BlockEntityRenderer {
             closed_chests,
             pot_patterns: HashMap::new(),
             visibility: None,
+            sign_texts: Mutex::default(),
         }
     }
     fn kind(&self, state: u32) -> &Kind {
@@ -922,11 +971,81 @@ 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(
@@ -1158,13 +1277,7 @@ 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),
@@ -1173,11 +1286,25 @@ 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",
@@ -1930,6 +2057,7 @@ 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.
@@ -2130,6 +2258,128 @@ mod tests {
         assert_eq!(out[2].uv, [0.5, 0.5]);
     }
 
+    #[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 };
@@ -2190,6 +2440,7 @@ mod tests {
             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);

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

@@ -4,8 +4,8 @@
 //! `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};

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

@@ -772,6 +772,27 @@ 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 {
     #[test]

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

@@ -230,7 +230,7 @@ pub struct Info {
 /// `VibrationSelector`: the closest, then highest-frequency candidate of a tick.
 #[derive(Clone, Debug, Default, PartialEq)]
 pub struct Selector {
-    pub(crate) current: Option<(Info, i64)>,
+    pub current: Option<(Info, i64)>,
 }
 /// `VibrationSystem.Data`.
 #[derive(Clone, Debug, Default, PartialEq)]
@@ -278,7 +278,7 @@ pub struct SpawnData {
 /// 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(crate) enum Next {
+pub enum Next {
     Potential(usize),
     Own(SpawnData),
 }
@@ -288,7 +288,7 @@ pub struct Spawner {
     pub spawn_delay: i32,
     /// `SpawnPotentials`: data and weight.
     pub potentials: Vec<(SpawnData, i32)>,
-    pub(crate) next: Option<Next>,
+    pub next: Option<Next>,
     pub min_spawn_delay: i32,
     pub max_spawn_delay: i32,
     pub spawn_count: i32,
@@ -301,6 +301,24 @@ pub struct Spawner {
     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 {
@@ -314,6 +332,26 @@ pub struct TrialConfig {
     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)]
@@ -347,6 +385,28 @@ pub struct TrialSpawner {
     /// 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 {

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

@@ -2,8 +2,9 @@
 //! count comparators read, the output it keeps, and the powered, automatic
 //! and condition flags `CommandBlock.tick` runs on.
 pub use crate::chunk::block_entity::CommandBlock;
-use crate::{
-    save::{number, text},
+use horizon_client_core::{
+    nbt_value::{number, text},
+    scoreboard,
     text::Text,
 };
 use horizon_world::nbt::Tag;
@@ -108,7 +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)
@@ -164,7 +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

@@ -5,12 +5,8 @@ pub use crate::chunk::block_entity::{
     Banner, Beacon, BlockEntity, Campfire, ChiseledBookshelf, Crafter, CreakingHeart, EndGateway,
     Furnace, FurnaceKind, Jukebox, Lectern, Skull, SkullSkin,
 };
-use crate::{
-    crafting::Recipes,
-    items::{ItemStack, Items},
-};
-use serde_json::Value;
-use std::{collections::HashMap, fs, path::Path, sync::Arc};
+use crate::items::ItemStack;
+use std::collections::HashMap;
 
 impl FurnaceKind {
     pub fn recipe_type(self) -> &'static str {
@@ -380,283 +376,7 @@ impl BlockEntity {
         }
     }
 }
-/// Evaluator for `context_int_provider` / `context_float_provider` values.
-pub struct Providers {
-    ints: HashMap<String, Value>,
-    floats: HashMap<String, Value>,
-}
-fn load_dir(dir: &Path, prefix: &str, out: &mut HashMap<String, Value>) {
-    let Ok(entries) = fs::read_dir(dir) else {
-        return;
-    };
-    for e in entries.flatten() {
-        let p = e.path();
-        let name = p
-            .file_stem()
-            .and_then(|s| s.to_str())
-            .unwrap_or("")
-            .to_owned();
-        if p.is_dir() {
-            load_dir(&p, &format!("{prefix}{name}/"), out);
-        } else if let Ok(bytes) = fs::read(&p)
-            && let Ok(v) = serde_json::from_slice(&bytes)
-        {
-            out.insert(format!("minecraft:{prefix}{name}"), v);
-        }
-    }
-}
-impl Providers {
-    pub fn load(root: &Path) -> Self {
-        let mut ints = HashMap::new();
-        let mut floats = HashMap::new();
-        load_dir(
-            &root.join("data/minecraft/context_int_provider"),
-            "",
-            &mut ints,
-        );
-        load_dir(
-            &root.join("data/minecraft/context_float_provider"),
-            "",
-            &mut floats,
-        );
-        Self { ints, floats }
-    }
-    fn eval(v: &Value, fast: bool, table: &HashMap<String, Value>, depth: u32) -> f64 {
-        if depth > 16 {
-            return 0.0;
-        }
-        match v {
-            Value::Number(n) => n.as_f64().unwrap_or(0.0),
-            Value::String(name) => table
-                .get(name)
-                .map_or(0.0, |v| Self::eval(v, fast, table, depth + 1)),
-            Value::Object(o) => {
-                let f =
-                    |k: &str| Self::eval(o.get(k).unwrap_or(&Value::Null), fast, table, depth + 1);
-                match o.get("type").and_then(Value::as_str).unwrap_or("") {
-                    "minecraft:div" => {
-                        let r = f("right");
-                        if r == 0.0 {
-                            0.0
-                        } else {
-                            (f("left") / r).trunc()
-                        }
-                    }
-                    "minecraft:mul" => f("left") * f("right"),
-                    "minecraft:add" | "minecraft:sum" => f("left") + f("right"),
-                    "minecraft:sub" => f("left") - f("right"),
-                    "minecraft:constant" => f("value"),
-                    "minecraft:conditional" => {
-                        // The only condition in the pinned data: block/fast_cooking.
-                        let condition = o.get("condition").and_then(Value::as_str)
-                            == Some("minecraft:block/fast_cooking");
-                        if condition && fast {
-                            f("on_true")
-                        } else {
-                            f("on_false")
-                        }
-                    }
-                    _ => 0.0,
-                }
-            }
-            _ => 0.0,
-        }
-    }
-    /// A plain `context_int_provider` value or reference (no context conditions).
-    pub fn int_value(&self, v: &Value) -> i32 {
-        Self::eval(v, false, &self.ints, 0) as i32
-    }
-    /// A plain `context_float_provider` value or reference; `default` when absent.
-    pub fn float_value(&self, v: &Value, default: f32) -> f32 {
-        if v.is_null() {
-            default
-        } else {
-            Self::eval(v, false, &self.floats, 0) as f32
-        }
-    }
-    #[cfg(test)]
-    pub fn empty() -> Self {
-        Self {
-            ints: HashMap::new(),
-            floats: HashMap::new(),
-        }
-    }
-    pub fn burn_time(&self, items: &Items, stack: &ItemStack, fast: bool) -> i32 {
-        items
-            .get(&stack.item)
-            .and_then(|i| i.fuel.as_ref())
-            .map_or(0, |(time, _)| Self::eval(time, fast, &self.ints, 0) as i32)
-    }
-    pub fn speed(&self, items: &Items, stack: &ItemStack, fast: bool) -> f32 {
-        items
-            .get(&stack.item)
-            .and_then(|i| i.fuel.as_ref())
-            .map_or(1.0, |(_, speed)| {
-                Self::eval(speed, fast, &self.floats, 0) as f32
-            })
-    }
-}
-fn remainder(item: &str) -> Option<&'static str> {
-    match item {
-        "minecraft:lava_bucket" | "minecraft:water_bucket" | "minecraft:milk_bucket" => {
-            Some("minecraft:bucket")
-        }
-        _ => None,
-    }
-}
-impl Furnace {
-    /// `AbstractFurnaceBlockEntity.setItem` on the input slot: anything but
-    /// the same item with the same components restarts cooking, with the
-    /// total time of the new input's recipe (200 ticks without one).
-    pub fn set_input(&mut self, recipes: &Recipes, stack: Option<ItemStack>) {
-        let same = match (&self.items[0], &stack) {
-            (Some(old), Some(new)) => old.same_item_same_components(new),
-            _ => false,
-        };
-        self.items[0] = stack;
-        if !same {
-            self.cooking_total = self.items[0]
-                .as_ref()
-                .and_then(|input| recipes.cook(self.kind.recipe_type(), input))
-                .map_or(200, |recipe| total_time(recipe.time, self.speed));
-            self.cooking_timer = 0;
-        }
-    }
-    /// `recipesUsed`, each recipe with its `experience` (0 for one this data pack does
-    /// not have), in the order `getRecipesToAwardAndPopExperience` pays them.
-    pub fn recipe_experience(&self, recipes: &Recipes) -> Vec<(u32, f32)> {
-        self.recipes_used
-            .iter()
-            .map(|(id, count)| (*count, recipes.cooking_experience(id)))
-            .collect()
-    }
-    /// A menu click wrote its slots into `items`, and `before` was the input
-    /// slot until then: the menu called `setItem` on it only if it changed
-    /// (`Slot.setByPlayer`; partial takes and merges keep the stack).
-    pub fn input_clicked(&mut self, recipes: &Recipes, before: Option<ItemStack>) {
-        if self.items[0] != before {
-            let after = std::mem::replace(&mut self.items[0], before);
-            self.set_input(recipes, after);
-        }
-    }
-    /// One server tick. Returns `Some(lit)` when the LIT block state must change.
-    pub fn tick(
-        &mut self,
-        recipes: &Recipes,
-        items: &Items,
-        providers: &Providers,
-    ) -> Option<bool> {
-        let was_lit = self.lit_remaining > 0;
-        let mut lit = false;
-        if self.lit_remaining > 0 {
-            self.lit_remaining -= 1;
-            lit = self.lit_remaining > 0;
-        }
-        let fast = self.kind.fast();
-        let has_ingredient = self.items[0].is_some();
-        let has_fuel = self.items[1].is_some();
-        if lit || has_fuel && has_ingredient {
-            if let Some(ingredient) = self.items[0].clone() {
-                if let Some(recipe) = recipes.cook(self.kind.recipe_type(), &ingredient) {
-                    if self.cooking_timer == 0 {
-                        self.cooking_total = total_time(recipe.time, self.speed);
-                    }
-                    let max = items.get(&recipe.result.item).map_or(64, |i| i.max_stack);
-                    let can_burn = match &self.items[2] {
-                        None => true,
-                        Some(out) => {
-                            out.item == recipe.result.item && out.count + recipe.result.count <= max
-                        }
-                    };
-                    if can_burn {
-                        if !lit {
-                            let fuel = self.items[1].clone();
-                            let time = fuel
-                                .as_ref()
-                                .map_or(0, |f| providers.burn_time(items, f, fast));
-                            let speed = fuel
-                                .as_ref()
-                                .map_or(1.0, |f| providers.speed(items, f, fast));
-                            self.lit_remaining = time;
-                            self.lit_total = time;
-                            self.speed = speed;
-                            if self.cooking_total > 0 && self.cooking_timer < self.cooking_total {
-                                let ratio = self.cooking_timer as f32 / self.cooking_total as f32;
-                                self.cooking_total = total_time(recipe.time, self.speed);
-                                self.cooking_timer =
-                                    (ratio * self.cooking_total as f32).ceil() as i32;
-                            }
-                            if time > 0 {
-                                if let Some(f) = self.items[1].as_mut() {
-                                    let item = f.item.clone();
-                                    f.count -= 1;
-                                    if f.count == 0 {
-                                        self.items[1] = remainder(&item).map(|r| ItemStack {
-                                            item: Arc::from(r),
-                                            count: 1,
-                                            damage: 0,
-                                            extra: None,
-                                        });
-                                    }
-                                }
-                                lit = true;
-                            }
-                        }
-                        if lit {
-                            self.cooking_timer += 1;
-                            if self.cooking_timer >= self.cooking_total {
-                                self.cooking_timer = 0;
-                                self.cooking_total = total_time(recipe.time, self.speed);
-                                match &mut self.items[2] {
-                                    Some(out) => out.count += recipe.result.count,
-                                    None => self.items[2] = Some(recipe.result.clone()),
-                                }
-                                *self
-                                    .recipes_used
-                                    .entry(recipe_used_key(&recipe.id))
-                                    .or_insert(0) += 1;
-                                // AbstractFurnaceBlockEntity.burn: drying a wet sponge fills
-                                // the bucket in the fuel slot.
-                                if self.items[0]
-                                    .as_ref()
-                                    .is_some_and(|i| &*i.item == "minecraft:wet_sponge")
-                                    && self.items[1]
-                                        .as_ref()
-                                        .is_some_and(|f| &*f.item == "minecraft:bucket")
-                                {
-                                    self.items[1] =
-                                        Some(ItemStack::new("minecraft:water_bucket", 1));
-                                }
-                                if let Some(i) = self.items[0].as_mut() {
-                                    i.count -= 1;
-                                    if i.count == 0 {
-                                        self.items[0] = None;
-                                    }
-                                }
-                            }
-                        } else {
-                            self.cooking_timer = 0;
-                        }
-                    } else {
-                        self.cooking_timer = 0;
-                    }
-                }
-            } else {
-                self.cooking_timer = 0;
-            }
-        } else if self.cooking_timer > 0 {
-            self.cooking_timer = (self.cooking_timer - 2).clamp(0, self.cooking_total);
-        }
-        (was_lit != lit).then_some(lit)
-    }
-}
-fn total_time(time: u32, speed: f32) -> i32 {
-    if speed > 0.0 {
-        (time as f32 / speed).ceil() as i32
-    } else {
-        time as i32
-    }
-}
+pub use crate::providers::Providers;
 
 /// `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).

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

@@ -326,16 +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())
@@ -603,7 +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

@@ -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())
     }

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

@@ -263,6 +263,16 @@ fn crumbling_uv(uv: vec2<f32>, packed_origin: vec2<f32>, sprite_size: vec2<f32>,
 
 // 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);

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

@@ -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 {

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

@@ -105,12 +105,9 @@ const COMPLETE_COLUMN: u32 = (1 << (crate::chunk::HEIGHT / 16)) - 1;
 /// its fixed-point UVs (`terrain.wgsl`'s `terrain_uv`).
 /// The world pass again after occlusion culling's test: it loads both
 /// targets (phase 2 draws over phase 1, reading the test's results).
-/// LevelRenderer: no sky inside lava or powder snow (sky fog ends within 2 blocks).
+/// `LevelRenderer.addSkyPass`: fluids and camera effects block the sky pass.
 fn sky_open(frame: &Frame) -> bool {
-    match frame.fog {
-        Some(f) => f.sky_end > 2.0,
-        None => !frame.underwater,
-    }
+    !frame.sky_blocked
 }
 
 /// The Overworld-style sky (disc, sunset, stars, void) draws this frame.
@@ -222,6 +219,9 @@ pub struct Frame<'a> {
     /// The `GameRenderer.bobHurt`/`bobView` pose multiplied into the
     /// projection (`crate::camera::bob_matrix`).
     pub bob: Mat4,
+    /// The spinning effect multiplied into the level's projection only
+    /// (`crate::camera::spinning_effect_matrix`), not the hand's.
+    pub spin: Mat4,
     pub sky: Sky,
     /// Render distance in blocks (fog end).
     pub distance: f32,
@@ -235,6 +235,8 @@ pub struct Frame<'a> {
     pub cave_culling: bool,
     /// Title screen: only the dedicated panorama cube map and the HUD.
     pub title: bool,
+    /// Lava, powder snow, blindness or darkness blocks the sky pass.
+    pub sky_blocked: bool,
     /// Dimensions without a skybox (the Nether) clear to the fog colour.
     pub skybox: bool,
     /// The End: clear to black and draw the resident sky box behind the world.
@@ -537,6 +539,9 @@ pub struct Renderer {
     hdr: Option<hdr::Hdr>,
     /// The HDR output the window's surface can present.
     hdr_output: Option<hdr::Output>,
+    /// The marker file of an HDR output that has not presented a frame yet
+    /// (`graphics::HDR_MARKER`).
+    hdr_marker: Option<std::path::PathBuf>,
     /// The shader pack's post-processing, and the dimension (legacy id) it was loaded for.
     pack_post: Option<(i32, Option<pack_post::PackPost>)>,
     /// The post passes of one of Horizon's own shader packs; never beside `pack_post`'s.
@@ -1964,7 +1969,7 @@ impl Renderer {
         // ulps covers that spread at any resolution while staying far below
         // the 0.001 a model's feet sit higher, so shadows never bleed onto
         // the feet.
-        let shadow_blob_pipeline = entity_pipeline(
+        let shadow_blob_pipeline = entity_pipeline_with(
             "Entity shadows",
             None,
             false,
@@ -1976,6 +1981,8 @@ impl Renderer {
             },
             alpha_blend,
             false,
+            "fs_entity_shadow",
+            wgpu::ColorWrites::ALL,
         );
         // RenderPipelines.ITEM_TRANSLUCENT: blended, depth tested. Drawn before
         // translucent terrain, it cannot write depth: the water behind a
@@ -2642,6 +2649,7 @@ impl Renderer {
             world_post,
             hdr: None,
             hdr_output,
+            hdr_marker: None,
             pack_post: None,
             native: None,
             pass_timing: pack_timing::PassTiming::logging(),
@@ -3200,9 +3208,17 @@ impl Renderer {
     }
     /// HDR output (Horizon setting): HDR10 or scRGB at `paper_white` nits, the world's
     /// highlights expanded up to `peak` nits. Off where the surface can't present it.
-    pub fn set_hdr(&mut self, on: bool, paper_white: f32, peak: f32) {
+    pub fn set_hdr(&mut self, on: bool, paper_white: f32, peak: f32, marker: &std::path::Path) {
         let output = self.hdr_output.filter(|_| on && self.surface.is_some());
         if output.is_some() != self.hdr.is_some() {
+            // If the game dies before HDR output shows a frame, the marker is still there at
+            // the next start, which then comes up with HDR off.
+            if output.is_some() {
+                let _ = std::fs::write(marker, "HDR output was being switched on\n");
+                self.hdr_marker = Some(marker.to_owned());
+            } else if let Some(marker) = self.hdr_marker.take() {
+                let _ = std::fs::remove_file(marker);
+            }
             let format = self.config.format.remove_srgb_suffix();
             self.hdr = output.map(|output| hdr::Hdr::new(&self.device, format, output));
             self.configure_surface();
@@ -3418,7 +3434,7 @@ impl Renderer {
             frame.fov_degrees,
             frame.yaw,
             frame.pitch,
-            frame.bob,
+            frame.bob * frame.spin,
             frame.depth_far,
         )
     }
@@ -4508,7 +4524,7 @@ impl Renderer {
             cull.bind_depth(&self.device, world_depth);
         }
         let cull = self.cull.as_ref().filter(|_| culling && solid_draws > 0);
-        let clear = if frame.title || (frame.end_sky && !frame.underwater) {
+        let clear = if frame.title || (frame.end_sky && !frame.underwater && sky_open(frame)) {
             wgpu::Color::BLACK
         } else {
             wgpu::Color {
@@ -5229,6 +5245,12 @@ impl Renderer {
                 startup_step(format_args!("presenting the first frame"));
             }
             self.queue.present(surface_frame);
+            if self.hdr.is_some()
+                && let Some(marker) = self.hdr_marker.take()
+            {
+                let _ = std::fs::remove_file(marker);
+                log::info!("Horizon renderer: HDR output presented its first frame");
+            }
             if reconfigure && let Some(surface) = &self.surface {
                 Self::configure(
                     &self.device,

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

@@ -25,12 +25,26 @@ pub const TRANSLUCENT_ITEM_OVERLAY: u32 = 32;
 /// A translucent item with an enchantment glint.
 pub const TRANSLUCENT_GLINT_ITEM_OVERLAY: u32 = 33;
 
+/// The material of a quad by its overlay (`MATERIALS` order).
+fn material(layer: u32) -> usize {
+    match layer {
+        11 => 1,
+        12 => 2,
+        WATER_MASK_OVERLAY => 3,
+        ENERGY_SWIRL_OVERLAY => 4,
+        SHADOW_OVERLAY => 5,
+        TRANSLUCENT_PARTICLE_OVERLAY => 6,
+        TRANSLUCENT_ITEM_OVERLAY | TRANSLUCENT_GLINT_ITEM_OVERLAY => 7,
+        _ => 0,
+    }
+}
+
 #[derive(Default)]
 pub(super) struct EntityBatch {
-    // Quad indices avoid copying vertices twice while grouping materials.
-    // Keep initialized high-water storage; local counts delimit active entries.
-    // Each bucket can hold all quads, removing per-quad Vec growth checks.
-    buckets: [Vec<usize>; MATERIALS],
+    // Runs of consecutive quads of one material (first quad, quad count): a
+    // model's quads share one, so whole runs are copied at once. Cleared each
+    // frame, keeping their storage.
+    runs: [Vec<(usize, usize)>; MATERIALS],
     pub(super) combined: Vec<Vertex>,
 }
 
@@ -43,50 +57,29 @@ impl EntityBatch {
         see_through: &[Vertex],
     ) -> [u32; MATERIALS] {
         let quads = entities.as_chunks::<4>().0;
-        for bucket in &mut self.buckets {
-            if bucket.len() < quads.len() {
-                bucket.resize(quads.len(), 0);
-            }
+        for runs in &mut self.runs {
+            runs.clear();
         }
         let mut counts = [0usize; MATERIALS];
-        for (index, quad) in quads.iter().enumerate() {
-            let material = match quad[0].layer {
-                11 => 1,
-                12 => 2,
-                WATER_MASK_OVERLAY => 3,
-                ENERGY_SWIRL_OVERLAY => 4,
-                SHADOW_OVERLAY => 5,
-                TRANSLUCENT_PARTICLE_OVERLAY => 6,
-                TRANSLUCENT_ITEM_OVERLAY | TRANSLUCENT_GLINT_ITEM_OVERLAY => 7,
-                _ => 0,
-            };
-            self.buckets[material][counts[material]] = index;
-            counts[material] += 1;
+        let mut start = 0;
+        while start < quads.len() {
+            let kind = material(quads[start][0].layer);
+            let end = quads[start + 1..]
+                .iter()
+                .position(|quad| material(quad[0].layer) != kind)
+                .map_or(quads.len(), |n| start + 1 + n);
+            self.runs[kind].push((start, end - start));
+            counts[kind] += end - start;
+            start = end;
         }
         let entity_vertices = quads.len() * 4;
-        self.combined.reserve(
-            (entity_vertices + additive.len() + hand.len() + see_through.len())
-                .saturating_sub(self.combined.len()),
-        );
+        self.combined.clear();
         self.combined
-            .resize(entity_vertices, bytemuck::Zeroable::zeroed());
-        if counts.contains(&quads.len()) {
-            // Uniform materials are already ordered; copy the whole batch.
-            self.combined.copy_from_slice(&entities[..entity_vertices]);
-        } else {
-            let mut offset = 0;
-            for (bucket, &count) in self.buckets.iter().zip(&counts) {
-                let bucket = &bucket[..count];
-                let end = offset + count * 4;
-                for (output, &index) in self.combined[offset..end]
-                    .as_chunks_mut::<4>()
-                    .0
-                    .iter_mut()
-                    .zip(bucket)
-                {
-                    *output = quads[index];
-                }
-                offset = end;
+            .reserve(entity_vertices + additive.len() + hand.len() + see_through.len());
+        for runs in &self.runs {
+            for &(first, count) in runs {
+                self.combined
+                    .extend_from_slice(&entities[first * 4..(first + count) * 4]);
             }
         }
         self.combined.extend_from_slice(additive);
@@ -174,12 +167,12 @@ mod tests {
         let hand = geometry(2, false);
         // Warm every bucket and the combined buffer to their maximum sizes.
         equivalent(&mut batch, &entities, &additive, &hand);
-        let capacities = batch.buckets.each_ref().map(|b| b.capacity());
+        let capacities = batch.runs.each_ref().map(|b| b.capacity());
         let capacity = batch.combined.capacity();
         let pointer = batch.combined.as_ptr();
         for length in [0, 1, 3, 4, 511, entities.len(), 17, 0, entities.len()] {
             equivalent(&mut batch, &entities[..length], &additive[..5], &hand[..3]);
-            assert_eq!(batch.buckets.each_ref().map(|b| b.capacity()), capacities);
+            assert_eq!(batch.runs.each_ref().map(|b| b.capacity()), capacities);
             assert_eq!(batch.combined.capacity(), capacity);
             assert_eq!(batch.combined.as_ptr(), pointer);
         }
@@ -188,11 +181,11 @@ mod tests {
         // Grow again, then confirm empty/small frames retain the new storage.
         let larger = geometry(8192, true);
         equivalent(&mut batch, &larger, &additive, &hand);
-        let capacities = batch.buckets.each_ref().map(|b| b.capacity());
+        let capacities = batch.runs.each_ref().map(|b| b.capacity());
         let capacity = batch.combined.capacity();
         for entities in [&larger[..7], &larger[..], &[]] {
             equivalent(&mut batch, entities, &[], &[]);
-            assert_eq!(batch.buckets.each_ref().map(|b| b.capacity()), capacities);
+            assert_eq!(batch.runs.each_ref().map(|b| b.capacity()), capacities);
             assert_eq!(batch.combined.capacity(), capacity);
         }
     }
@@ -255,9 +248,9 @@ mod tests {
                 before[7] as f64 / after[7] as f64,
                 batch.combined.capacity() * std::mem::size_of::<Vertex>()
                     + batch
-                        .buckets
+                        .runs
                         .iter()
-                        .map(|b| b.capacity() * std::mem::size_of::<usize>())
+                        .map(|b| b.capacity() * std::mem::size_of::<(usize, usize)>())
                         .sum::<usize>()
             );
         }

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

@@ -361,8 +361,9 @@ impl NativePost {
 pub fn frame_inputs(frame: &Frame, size: [u32; 2], seconds: f32, index: u32) -> FrameInputs {
     let aspect = size[0] as f32 / size[1].max(1) as f32;
     let view = crate::camera::view_matrix(frame.yaw, frame.pitch);
-    let projection =
-        super::world_projection(frame.fov_degrees, aspect, frame.depth_far) * frame.bob;
+    let projection = super::world_projection(frame.fov_degrees, aspect, frame.depth_far)
+        * frame.bob
+        * frame.spin;
     // A celestial body's direction at `angle` degrees (SkyRenderer: Y -90°, then X by the
     // angle, of straight up): overhead at 0, rising in the east (+x).
     let body = |angle: f32| {

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

@@ -287,7 +287,8 @@ impl FrameUniforms {
             aspect,
             0.05,
             frame.depth_far,
-        ) * frame.bob;
+        ) * frame.bob
+            * frame.spin;
         let camera = frame.camera.as_vec3();
         let (previous_camera, previous_view, previous_projection) =
             self.previous