Merge pull request #3506 from horizon-rust/fix/launcher-delete-instance

🤖 Agent: launcher-java-1 verified this head: PR checks green (verify, launcher), launcher build matrix green on Windows, macOS and Linux (dry run https://github.com/horizon-rust/horizon/actions/runs/40817273793), pr_ready --quick green with the new test deleted_instances_go_to_the_trash_and_are_forgotten; docs/launcher-commands.md regenerated.

.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/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

@@ -35,11 +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` |
@@ -99,6 +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`
@@ -110,7 +114,8 @@ 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 |

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"
@@ -1372,7 +1378,6 @@ dependencies = [
  "ab_glyph",
  "bytemuck",
  "chrono",
- "cpal",
  "flate2",
  "gilrs",
  "glam",
@@ -1380,6 +1385,7 @@ dependencies = [
  "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",
@@ -1434,6 +1440,48 @@ dependencies = [
  "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"
@@ -1877,6 +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"
@@ -2691,6 +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"

Cargo.toml

@@ -9,6 +9,7 @@ members = [
     "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",
@@ -61,8 +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" }
 

README.md

@@ -29,9 +29,9 @@ Horizon is Minecraft: Java Edition 26.3 rewritten in Rust: a native game that re
 
 ## 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 and updates the game, 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>
@@ -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.

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/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/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/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/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}"))?;
         }
@@ -217,6 +217,7 @@ 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();

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

@@ -597,6 +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(
@@ -757,6 +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 {
@@ -768,7 +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"),
@@ -898,6 +936,7 @@ impl BlockEntityRenderer {
             closed_chests,
             pot_patterns: HashMap::new(),
             visibility: None,
+            sign_texts: Mutex::default(),
         }
     }
     fn kind(&self, state: u32) -> &Kind {
@@ -932,11 +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(
@@ -1168,13 +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),
@@ -1954,6 +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.
@@ -2154,6 +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 };
@@ -2214,6 +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/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/containers.rs

@@ -5,11 +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 std::{collections::HashMap, sync::Arc};
+use crate::items::ItemStack;
+use std::collections::HashMap;
 
 impl FurnaceKind {
     pub fn recipe_type(self) -> &'static str {
@@ -380,167 +377,6 @@ impl BlockEntity {
     }
 }
 pub use crate::providers::Providers;
-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
-    }
-}
 
 /// `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/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

@@ -539,6 +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.
@@ -1966,7 +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,
@@ -1978,6 +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
@@ -2644,6 +2649,7 @@ impl Renderer {
             world_post,
             hdr: None,
             hdr_output,
+            hdr_marker: None,
             pack_post: None,
             native: None,
             pass_timing: pack_timing::PassTiming::logging(),
@@ -3202,9 +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();
@@ -5231,6 +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/graphics.rs

@@ -5,6 +5,9 @@
 use std::{fs, path::Path};
 
 pub const FILE: &str = "horizon-graphics.txt";
+/// Written beside it before HDR output is switched on and removed once the first HDR frame is
+/// presented. Found at the next start, it means HDR output took the game down, so HDR starts off.
+pub const HDR_MARKER: &str = "horizon-hdr-pending";
 
 /// Simple-level presets. `Custom` leaves every option as the player set it.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
@@ -310,9 +313,17 @@ fn bool_text(v: bool) -> &'static str {
 }
 impl Graphics {
     pub fn load(dir: &Path) -> Self {
-        fs::read_to_string(dir.join(FILE))
+        let mut g: Self = fs::read_to_string(dir.join(FILE))
             .map(|t| Self::parse(&t))
-            .unwrap_or_default()
+            .unwrap_or_default();
+        if fs::remove_file(dir.join(HDR_MARKER)).is_ok() && g.hdr {
+            g.hdr = false;
+            g.save(dir);
+            log::warn!(
+                "the last start ended before HDR output showed a frame; HDR is off now (graphics option hdr, in {FILE})"
+            );
+        }
+        g
     }
     pub fn parse(text: &str) -> Self {
         let mut g = Self::default();
@@ -588,6 +599,21 @@ mod tests {
         }
     }
 
+    #[test]
+    fn every_preset_keeps_the_animated_textures_on() {
+        // The Performance preset used to turn them off, which froze the fire,
+        // the water, the lava and the portals (#2064).
+        assert!(Graphics::default().animated_textures);
+        for preset in Preset::ALL {
+            let mut s = crate::settings::Settings::default();
+            apply_preset(preset, &mut s);
+            assert!(
+                s.horizon.animated_textures,
+                "{preset:?} turned the animated textures off"
+            );
+        }
+    }
+
     #[test]
     fn automatic_workers_leave_a_core_as_vanilla_does() {
         let g = Graphics::default();