geometry.rs: GbuffersInputs only in its tests; lockfiles: the pipeline crate takes naga

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Translated programs' types move to horizon-render-pipeline
2026-11-09 10:39:46 -10:00 · 2026-11-09 16:46:06 +01:00 · 2026-11-09 16:42:43 +01:00 · 2026-11-09 16:35:58 +01:00 · 2026-11-09 16:35:02 +01:00 · 2026-11-09 16:24:07 +01:00
723 changed files with 10711 additions and 27494 deletions
@@ -80,24 +80,21 @@ jobs:
          rustup toolchain install stable --profile minimal --component rustfmt --component clippy
          rustup default stable
          echo "WGPU_BACKEND=dx12" >> "$GITHUB_ENV"
-      # On a pull request, the next three checks compare with HEAD^1: the main that GitHub's merge commit puts the pull
-      # request on. pull_request.base.sha is main at the pull request's last push and falls behind, so main's own
-      # changes since then would count as the pull request's (#13874).
      # docs/layers.md: a crate depends only on its own layer or a lower one; today's exceptions only shrink.
      - name: Crates follow the layers
        env:
-          BASE: ${{ github.event_name == 'pull_request' && 'HEAD^1' || '' }}
-        run: python3 tools/check_layers.py ${BASE:+--base "$BASE"}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: python3 tools/check_layers.py ${BASE_SHA:+--base "$BASE_SHA"}
      # docs/layers.md#built-in-addresses: every built-in outside address in the Horizon layer's home; the rest only shrinks.
      - name: Built-in addresses stay in their home
        env:
-          BASE: ${{ github.event_name == 'pull_request' && 'HEAD^1' || '' }}
-        run: python3 tools/check_addresses.py ${BASE:+--base "$BASE"}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: python3 tools/check_addresses.py ${BASE_SHA:+--base "$BASE_SHA"}
      # docs/layers.md#file-size: a Rust file over 3000 lines may not grow (pull requests; main has no base to compare).
      - name: Big files don't grow
        env:
-          BASE: ${{ github.event_name == 'pull_request' && 'HEAD^1' || '' }}
-        run: python3 tools/check_file_size.py ${BASE:+--base "$BASE"}
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: python3 tools/check_file_size.py ${BASE_SHA:+--base "$BASE_SHA"}
      - name: Test offline research tooling
        run: python -m unittest discover -s tests -v
      - name: Install Rust toolchain and the ALSA and udev headers the client links against
@@ -220,17 +217,17 @@ jobs:
          $clang = Get-Command clang -ErrorAction Stop
          Write-Output "Using $($clang.Source)"
          & $clang.Source --version
-      - name: Build the game for native Windows ARM64 (the official game, as game-build.yml ships it)
-        run: cargo build --release --locked --target aarch64-pc-windows-msvc -p horizon-official --bin horizon-official -p horizon-client-lib --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
+      - name: Build the game for native Windows ARM64
+        run: cargo build --release --locked --target aarch64-pc-windows-msvc -p horizon-client -p horizon-client-lib --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
      - name: Check the game's PE machine
-        run: python tools/check_pe_arch.py arm64 target/aarch64-pc-windows-msvc/release/horizon-official.exe target/aarch64-pc-windows-msvc/release/horizon-ctl.exe target/aarch64-pc-windows-msvc/release/horizon-prepare.exe target/aarch64-pc-windows-msvc/release/horizon-server.exe
+        run: python tools/check_pe_arch.py arm64 target/aarch64-pc-windows-msvc/release/horizon-client.exe target/aarch64-pc-windows-msvc/release/horizon-ctl.exe target/aarch64-pc-windows-msvc/release/horizon-prepare.exe target/aarch64-pc-windows-msvc/release/horizon-server.exe
      - name: Check game DLL imports
-        run: python tools/check_imports.py target/aarch64-pc-windows-msvc/release/horizon-official.exe target/aarch64-pc-windows-msvc/release/horizon-ctl.exe target/aarch64-pc-windows-msvc/release/horizon-prepare.exe target/aarch64-pc-windows-msvc/release/horizon-server.exe
+        run: python tools/check_imports.py target/aarch64-pc-windows-msvc/release/horizon-client.exe target/aarch64-pc-windows-msvc/release/horizon-ctl.exe target/aarch64-pc-windows-msvc/release/horizon-prepare.exe target/aarch64-pc-windows-msvc/release/horizon-server.exe
      - name: Start every game executable
        shell: pwsh
        run: |
          $ErrorActionPreference = 'Stop'
-          $client = 'target/aarch64-pc-windows-msvc/release/horizon-official.exe'
+          $client = 'target/aarch64-pc-windows-msvc/release/horizon-client.exe'
          $output = & $client --help 2>&1
          if ($LASTEXITCODE -ne 0 -or ($output -join "`n") -notmatch '--resources') { throw 'horizon-client --help failed' }
          foreach ($binary in @('horizon-ctl.exe', 'horizon-prepare.exe', 'horizon-server.exe')) {
@@ -168,14 +168,9 @@ jobs:
      - name: ALSA and udev headers
        if: runner.os == 'Linux' && !matrix.musl
        run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libasound2-dev libudev-dev
-      - name: Build the official game, horizon-ctl, horizon-prepare and horizon-server
+      - name: Build the client, horizon-ctl, horizon-prepare and horizon-server
        if: ${{ !matrix.musl }}
-        run: cargo build --release --locked ${{ matrix.target && format('--target {0}', matrix.target) || '' }} -p horizon-official --bin horizon-official -p horizon-client-lib --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
-      - name: The official game is the game players get, under its name
-        # horizon-official: horizon-client's game with Horizon's own parts plugged in (docs/layers.md, "How a
-        # Horizon crate plugs in"). Everything below, the launcher and players know it as horizon-client.
-        if: ${{ !matrix.musl }}
-        run: cp -f "$BIN/horizon-official${{ matrix.exe }}" "$BIN/horizon-client${{ matrix.exe }}"
+        run: cargo build --release --locked ${{ matrix.target && format('--target {0}', matrix.target) || '' }} -p horizon-client -p horizon-client-lib --bin horizon-client --bin horizon-ctl -p horizon-prepare --bin horizon-prepare -p horizon-server --bin horizon-server
      - name: Every program the release folder takes was built
        if: ${{ !matrix.musl }}
        run: |
@@ -201,9 +201,6 @@ jobs:
      - name: Verify Windows executable architecture
        if: runner.os == 'Windows'
        run: python ../tools/check_pe_arch.py "${{ matrix.pe_arch }}" "$BIN/${{ matrix.binary }}"
-      - name: Unrelated DLLs cannot intercept launcher or setup startup
-        if: runner.os == 'Windows'
-        run: python ../tools/test_launcher_dll_search.py "$BIN/${{ matrix.binary }}"
      - name: The version is the release's
        run: |
          out=$("$BIN/${{ matrix.binary }}" --version)
@@ -181,7 +181,7 @@ jobs:
          musl=(); if [[ -f dist/horizon-linux-musl-x86_64.tar.gz ]]; then musl=(dist/horizon-linux-musl-x86_64.tar.gz)
          else echo "::warning::horizon-linux-musl-x86_64.tar.gz is missing: SHA256SUMS goes out without it"; fi
          bash tools/ci/sign_release.sh nightly dist/horizon-linux-x86_64.tar.gz dist/horizon-windows-x64.zip \
-            ${arm64[@]+"${arm64[@]}"} ${musl[@]+"${musl[@]}"} \
+            "${arm64[@]}" "${musl[@]}" \
            dist/horizon-macos-arm64.zip dist/horizon-macos-x64.zip dist/horizon-server-linux-x86_64.tar.gz \
            dist/horizon-source.tar.gz
      - uses: actions/upload-artifact@v7
@@ -267,9 +267,9 @@ jobs:
          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#Game files the launcher installs (Nightly): Linux (horizon-linux-x86_64.tar.gz)" \
-            ${musl[@]+"${musl[@]}"} \
+            "${musl[@]}" \
            "dist/horizon-windows-x64.zip#Game files the launcher installs (Nightly): Windows (horizon-windows-x64.zip)" \
-            ${arm64[@]+"${arm64[@]}"} \
+            "${arm64[@]}" \
            "dist/horizon-macos-arm64.zip#Game files the launcher installs (Nightly): macOS on Apple Silicon (horizon-macos-arm64.zip)" \
            "dist/horizon-macos-x64.zip#Game files the launcher installs (Nightly): macOS on Intel (horizon-macos-x64.zip)" \
            "dist/horizon-server-linux-x86_64.tar.gz#Nightly dedicated server for Linux (horizon-server-linux-x86_64.tar.gz)" \
@@ -44,8 +44,6 @@ Feature → files → harness for the most-changed areas: [docs/architecture.md]
 - **Machine translations stay unreviewed.** `tools/lang_review/` records only text a person who speaks the language
  wrote or checked; never `lang_coverage.py --mark-reviewed` machine text ([docs/translations.md](docs/translations.md)).
 - **Controllers reach what registers.** Draw controls with a registering helper (`ui::button`, `settings_shell::foot_button`); `graphics_style::button` and `screen_draw::button` only paint, and registering one part of a screen ends its crosshair, so register all of it.
- **Render passes keep HDR's light.** A pass that reads, filters or redraws the world's picture (upscaling,
-  anti-aliasing, sharpening, frame generation, post effects, captures) follows [docs/hdr-passes.md](docs/hdr-passes.md).

 ## Crates

@@ -81,7 +79,6 @@ Game workspace (root `Cargo.toml`); `launcher/` and `crates/horizon-telemetry-se
 | `horizon-telemetry`, `horizon-telemetry-server`, `horizon-bench` | Opt-in data collection, its ingest server, the benchmark report format |
 | `horizon-system` | The machine the game runs on (OS, CPU, memory, drive, power, GPU maker and memory), for the crash report, the renderer's GPU info and telemetry |
 | `horizon-platform` | The platform's public API: what the Horizon layer may use of the engine ([docs/layers.md](docs/layers.md)); re-exports `horizon-system` today |
-| `horizon-hooks`, `horizon-game`, `horizon-official`, `horizon-heartbeat` | The layer seam: the engine's hooks for crates above it, the game an executable starts, the official executable (shipped as `horizon-client`) that registers Horizon's in-game parts, the first of them ([docs/layers.md](docs/layers.md#how-a-horizon-crate-plugs-in)) |
 | `horizon-dualsense`, `horizon-threads`, `horizon-release-sign`, `horizon-bots`, `xtask` | DualSense output, thread priorities, signed release checksums, load-test bots, repo tasks |
 | `launcher/` | GPUI launcher: `main.rs` (UI), `backend.rs` (installs, updates), `cli.rs`, `mcp.rs`, `*_page.rs` |

@@ -13,14 +13,6 @@ else (videos, Discord and other community material) lives elsewhere.
 suggest something. A pull request for a roadmap item carries its `roadmap:<id>` label; ideas go to the suggestion
 queue (the hub, or `/suggest` on Discord) rather than to issues, which are for bugs.

-**Mod-related pull requests go to [arismoko/horizon](https://github.com/arismoko/horizon)**, the fork that carries the
-mod API and reviews and merges that work. That covers the mod API, native hooks and events for mods, native mods,
-content mods (`.hmod`), mixins, wasm mods, `cargo horizon-mod`, `horizon-mods`, mod builds and the registry, and
-their docs ([mods](docs/mods.md), [native mods](docs/native-mods.md)). Open the pull request there from your usual
-branch. Mod-related pull requests opened here are closed with a pointer to it. Engine extension points that Horizon's
-own crates register (the [layer split](docs/layers.md)), resource and shader pack formats, and gameplay fixes stay
-here.
-
 ## Build it

 - **Prerequisites:** Rust (stable), Python 3.10+, JDK 25, and on Linux the ALSA and udev headers
@@ -1418,7 +1418,6 @@ dependencies = [
 name = "horizon-chat-filter"
 version = "0.1.0"
 dependencies = [
- "horizon-server-files",
 "serde",
 "serde_json",
 "toml",
@@ -1451,7 +1450,6 @@ dependencies = [
 "horizon-dualsense",
 "horizon-friends",
 "horizon-hdr",
- "horizon-hooks",
 "horizon-items",
 "horizon-mod-api-gen",
 "horizon-mods",
@@ -1502,6 +1500,7 @@ version = "0.1.0"
 dependencies = [
 "arboard",
 "horizon-client-core",
+ "horizon-dualsense",
 "horizon-theme",
 "png",
 "winit",
@@ -1529,8 +1528,10 @@ dependencies = [
 "horizon-client-render",
 "horizon-command",
 "horizon-core",
+ "horizon-cosmetics",
+ "horizon-dualsense",
+ "horizon-friends",
 "horizon-hdr",
- "horizon-hooks",
 "horizon-items",
 "horizon-mcp",
 "horizon-mods",
@@ -1586,12 +1587,13 @@ dependencies = [
 "horizon-core",
 "horizon-cosmetics",
 "horizon-hdr",
- "horizon-hooks",
 "horizon-items",
+ "horizon-mod-api-gen",
 "horizon-narrator",
 "horizon-optifine",
 "horizon-polytone",
 "horizon-protocol",
+ "horizon-render-pipeline",
 "horizon-shader-api",
 "horizon-shaders",
 "horizon-system",
@@ -1667,7 +1669,6 @@ dependencies = [
 "getrandom 0.3.4",
 "hkdf",
 "horizon-addresses",
- "horizon-platform",
 "if-addrs",
 "serde",
 "serde_json",
@@ -1676,15 +1677,6 @@ dependencies = [
 "spake2",
 ]

-[[package]]
-name = "horizon-game"
-version = "0.1.0"
-dependencies = [
- "horizon-client",
- "horizon-mods",
- "horizon-threads",
-]
-
 [[package]]
 name = "horizon-hdr"
 version = "0.1.0"
@@ -1696,19 +1688,6 @@ dependencies = [
 "wgpu",
 ]

-[[package]]
-name = "horizon-heartbeat"
-version = "0.1.0"
-dependencies = [
- "horizon-platform",
- "horizon-telemetry",
- "log",
-]
-
-[[package]]
-name = "horizon-hooks"
-version = "0.1.0"
-
 [[package]]
 name = "horizon-items"
 version = "0.1.0"
@@ -1789,18 +1768,6 @@ dependencies = [
 "windows 0.62.2",
 ]

-[[package]]
-name = "horizon-official"
-version = "0.1.0"
-dependencies = [
- "horizon-friends",
- "horizon-game",
- "horizon-heartbeat",
- "horizon-platform",
- "log",
- "winresource",
-]
-
 [[package]]
 name = "horizon-optifine"
 version = "0.1.0"
@@ -1815,13 +1782,7 @@ dependencies = [
 name = "horizon-platform"
 version = "0.1.0"
 dependencies = [
- "horizon-core",
- "horizon-hooks",
- "horizon-prepare",
- "horizon-protocol",
- "horizon-server-files",
 "horizon-system",
- "horizon-world",
 ]

 [[package]]
@@ -1892,6 +1853,14 @@ dependencies = [
 "ring",
 ]

+[[package]]
+name = "horizon-render-pipeline"
+version = "0.1.0"
+dependencies = [
+ "bytemuck",
+ "naga",
+]
+
 [[package]]
 name = "horizon-server"
 version = "0.1.0"
@@ -1903,9 +1872,11 @@ dependencies = [
 "horizon-anticheat",
 "horizon-bench",
 "horizon-chat-filter",
+ "horizon-core",
 "horizon-mcp",
- "horizon-platform",
 "horizon-release-sign",
+ "horizon-server-files",
+ "horizon-world",
 "libc",
 "p12-keystore",
 "png",
@@ -1938,7 +1909,7 @@ dependencies = [
 name = "horizon-shader-api"
 version = "0.1.0"
 dependencies = [
- "bytemuck",
+ "horizon-render-pipeline",
 "naga",
 "png",
 "serde",
@@ -1954,6 +1925,7 @@ version = "0.1.0"
 dependencies = [
 "half",
 "horizon-core",
+ "horizon-render-pipeline",
 "naga",
 "png",
 "zip",
@@ -30,10 +30,6 @@ members = [
    "crates/horizon-telemetry",
    "crates/horizon-system",
    "crates/horizon-platform",
-    "crates/horizon-hooks",
-    "crates/horizon-game",
-    "crates/horizon-official",
-    "crates/horizon-heartbeat",
    "crates/horizon-bench",
    "crates/horizon-friends",
    "crates/horizon-relay",
@@ -43,6 +39,7 @@ members = [
    "crates/cargo-horizon-mod",
    "crates/horizon-port-pack",
    "crates/horizon-shaders",
+    "crates/horizon-render-pipeline",
    "crates/horizon-optifine",
    "crates/horizon-polytone",
    "crates/horizon-shader-api",
@@ -129,9 +129,8 @@ ports to WGSL of the optical flow and frame interpolation shaders of the
 [AMD FidelityFX SDK](https://github.com/GPUOpen-LibrariesAndSDKs/FidelityFX-SDK) 1.1.4
 (`sdk/include/FidelityFX/gpu/{opticalflow,frameinterpolation}`, at commit
 [c6efa6bf7f20](https://github.com/GPUOpen-LibrariesAndSDKs/FidelityFX-SDK/tree/c6efa6bf7f2027b3ec94f28578bb5965eabb9e55)),
-and `optical_flow.rs` and `interpolation.rs` follow the SDK's
-`sdk/src/components/{opticalflow/ffx_opticalflow.cpp,frameinterpolation/ffx_frameinterpolation.cpp}`
-(their passes, their order and their dispatch sizes). Copyright (C) 2024 Advanced Micro Devices,
+and `optical_flow.rs` follows the SDK's `sdk/src/components/opticalflow/ffx_opticalflow.cpp`
+(its passes, their order and their dispatch sizes). Copyright (C) 2024 Advanced Micro Devices,
 Inc., under the MIT license, whose text heads each file. AMD and FidelityFX are AMD's
 trademarks; Horizon is not affiliated with AMD.

@@ -90,7 +90,6 @@ impl Report {
 /// The kind a file's extension says.
 pub fn kind_of(path: &Path) -> Option<Kind> {
    match path.extension()?.to_str()? {
-        "hmod" if horizon_mods::index::native::holds(path) => Some(Kind::NativeMod),
        "hmod" => Some(Kind::Mod),
        "hnmod" => Some(Kind::NativeMod),
        "hpack" => Some(Kind::Modpack),
@@ -377,13 +377,6 @@ mod tests {
        zip.finish().unwrap();
        let report = check::check(&hnmod, check::kind_of(&hnmod).unwrap(), None, None).unwrap();
        assert!(report.text().contains("machine_mod"), "{}", report.text());
-        let combined = dir.join("machine_mod.hmod");
-        std::fs::copy(&hnmod, &combined).unwrap();
-        assert_eq!(
-            check::kind_of(&combined),
-            Some(horizon_mods::index::Kind::NativeMod)
-        );
-        assert!(check::check(&combined, check::kind_of(&combined).unwrap(), None, None).is_ok());
        // A pin that is not a commit is refused; with none, the folder builds on the
        // instance's Horizon.
        let bad = [
@@ -80,8 +80,8 @@ pub fn main(args: &[String]) -> Result<(), String> {
            };
            let author = flag(rest, "--author").ok_or(USAGE)?;
            let (base, _) = registry::load(Path::new(base)).map_err(lines)?;
-            let (head, revoked) = registry::load(Path::new(head)).map_err(lines)?;
-            let review = registry::review_with_revoked(&base, &head, &revoked, author);
+            let (head, _) = registry::load(Path::new(head)).map_err(lines)?;
+            let review = registry::review(&base, &head, author);
            if rest.iter().any(|a| a == "--json") {
                let json = serde_json::json!({"errors": review.errors, "notes": review.notes});
                println!("{json}");
@@ -26,23 +26,18 @@ pub struct AnimationMetadata {
 pub enum ClipMode {
    /// `day_time`: frame 0 at time 0, the last at the cycle's end, then again.
    DayTime { cycle: i64 },
-    /// `screen_time`: the ticks the open screen has been open, over the cycle, held on the last
-    /// frame once it has run (it doesn't loop, measured on the real mod).
-    ScreenTime { cycle: i64 },
    /// `weather`: frame 0 in clear weather, 1 in rain, 2 in a storm (the rain and thunder levels
    /// added up), at most the last.
    Weather,
    /// A Polytone expression: its value's fraction is how far through the animation it is.
    Expression(String),
-    /// `game_time`, `season`: not driven; the animation runs on ticks.
+    /// `game_time`, `screen_time`, `season`: not driven yet; the animation runs on ticks.
    Unsupported(String),
 }

 /// The values [`ClipMode`]s read this frame.
 pub struct ModeInputs<'a> {
    pub day_time: i64,
-    /// The ticks the open screen has been open (0 without one).
-    pub screen_time: i64,
    /// The rain level plus the thunder level, 0 to 2.
    pub weather: f32,
    /// An expression's value this frame, by its source.
@@ -121,8 +116,7 @@ impl AnimationMetadata {
                    match mode.as_str() {
                        "day_time" => ClipMode::DayTime { cycle },
                        "weather" => ClipMode::Weather,
-                        "screen_time" => ClipMode::ScreenTime { cycle },
-                        "game_time" | "season" => ClipMode::Unsupported(mode),
+                        "game_time" | "screen_time" | "season" => ClipMode::Unsupported(mode),
                        _ => ClipMode::Expression(mode),
                    }
                }),
@@ -245,9 +239,6 @@ impl AnimationClip {
    pub fn sample_mode(&self, inputs: &ModeInputs) -> Option<AnimationSample> {
        let fraction = match self.mode.as_ref()? {
            ClipMode::DayTime { cycle } => day_fraction(inputs.day_time, *cycle),
-            ClipMode::ScreenTime { cycle } => {
-                (inputs.screen_time.max(0) as f64 / *cycle as f64).min(1.0 - f64::EPSILON)
-            }
            ClipMode::Weather => {
                let last = self.sequence.len() - 1;
                let index = (inputs.weather.max(0.0) as usize).min(last);
@@ -297,7 +288,6 @@ mod mode_tests {
        let expression = move |_: &str| Some(value);
        clip.sample_mode(&ModeInputs {
            day_time,
-            screen_time: day_time,
            weather,
            expression: &expression,
        })
@@ -312,13 +302,6 @@ mod mode_tests {
            .map(|t| frame(&day, t, 0.0, 0.0))
            .into();
        assert_eq!(frames, [0, 1, 2, 3, 1]);
-        // 26.3-6.8.6, four frames over 200 ticks: 40 ticks open show the first, and from ten
-        // seconds on the last, even after 27 (it doesn't loop).
-        let screen = clip(r#"{"frametime": 1, "mode": "screen_time", "time_cycle_duration": 200}"#);
-        let frames: Vec<u32> = [0, 40, 200, 360, 540]
-            .map(|t| frame(&screen, t, 0.0, 0.0))
-            .into();
-        assert_eq!(frames, [0, 0, 3, 3, 3]);
        let value = clip(r#"{"frametime": 1, "mode": "0.6"}"#);
        assert_eq!(frame(&value, 0, 0.0, 0.6), 2);
        assert_eq!(frame(&value, 0, 0.0, 2.0), 0);
@@ -338,7 +321,6 @@ mod mode_tests {
            clip(r#"{"frametime": 1}"#)
                .sample_mode(&ModeInputs {
                    day_time: 0,
-                    screen_time: 0,
                    weather: 0.0,
                    expression: &|_| None
                })
@@ -348,7 +330,6 @@ mod mode_tests {
            clip(r#"{"frametime": 1, "mode": "season"}"#)
                .sample_mode(&ModeInputs {
                    day_time: 0,
-                    screen_time: 0,
                    weather: 0.0,
                    expression: &|_| None
                })
@@ -7,8 +7,6 @@ rust-version.workspace = true
 description = "The dedicated server's chat filter: its [chat_filter] settings, the slur list's matcher and the mutes, with no game state (docs/chat-filter.md)"

 [dependencies]
-# The moderation durations, shared with `/tempban`.
-horizon-server-files = { path = "../horizon-server-files" }
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"
 toml = "1.1"
@@ -10,9 +10,6 @@ use std::path::{Path, PathBuf};

 mod normalise;

-pub use horizon_server_files::duration::{
-    DurationUnit, duration_parts, duration_text, now_millis, parse_duration,
-};
 pub use normalise::{Run, Text};

 /// The list built into the game, used when `words_file` is empty.
@@ -477,6 +474,61 @@ pub fn append_log(path: &Path, line: &str) -> std::io::Result<()> {
    writeln!(f, "{line}")
 }

+/// `/tempmute`'s duration in milliseconds: a positive whole number and a unit, `s`, `m`, `h`, `d` or
+/// `w` (`10m`, `2h`, `1d`).
+pub fn parse_duration(text: &str) -> Option<i64> {
+    let unit = match text.chars().last()? {
+        's' => 1_000,
+        'm' => MINUTE,
+        'h' => 60 * MINUTE,
+        'd' => 24 * 60 * MINUTE,
+        'w' => 7 * 24 * 60 * MINUTE,
+        _ => return None,
+    };
+    let count: i64 = text[..text.len() - 1].parse().ok()?;
+    (count > 0).then(|| count.checked_mul(unit)).flatten()
+}
+
+/// The unit used when presenting a moderation duration to a player.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum DurationUnit {
+    Minute,
+    Hour,
+    Day,
+}
+
+/// A duration's rounded count and unit, shared by logs and translated replies.
+pub fn duration_parts(millis: i64) -> (i64, DurationUnit) {
+    let (unit, kind) = if millis <= 60 * MINUTE {
+        (MINUTE, DurationUnit::Minute)
+    } else if millis <= 48 * 60 * MINUTE {
+        (60 * MINUTE, DurationUnit::Hour)
+    } else {
+        (24 * 60 * MINUTE, DurationUnit::Day)
+    };
+    (
+        millis.div_euclid(unit) + i64::from(millis.rem_euclid(unit) > 0),
+        kind,
+    )
+}
+
+/// `millis` for logs, rounded up: minutes up to an hour, hours up to two days, then days.
+pub fn duration_text(millis: i64) -> String {
+    let (count, unit) = duration_parts(millis);
+    let unit = match unit {
+        DurationUnit::Minute => "minute",
+        DurationUnit::Hour => "hour",
+        DurationUnit::Day => "day",
+    };
+    format!("{count} {unit}{}", if count == 1 { "" } else { "s" })
+}
+
+pub fn now_millis() -> i64 {
+    std::time::SystemTime::now()
+        .duration_since(std::time::UNIX_EPOCH)
+        .map_or(0, |d| d.as_millis() as i64)
+}
+
 /// `YYYY-MM-DDTHH:MM:SSZ` for epoch milliseconds.
 pub fn utc(millis: i64) -> String {
    let secs = millis.div_euclid(1000);
@@ -13,9 +13,11 @@ winit = "0.30.13"
 horizon-theme = { path = "../horizon-theme" }
 png = "0.18"
 arboard = { version = "3.6.1", default-features = false, features = ["wayland-data-control"] }
+# The DualSense's trigger effects (the `controllers` feature).
+horizon-dualsense = { path = "../horizon-dualsense", optional = true }

 [features]
-controllers = []
+controllers = ["dep:horizon-dualsense"]

 [lints]
 workspace = true
@@ -1523,8 +1523,9 @@ impl Rumble {
    }
 }

-/// What a trigger feels like, from what its action is doing (docs/controllers.md "Adaptive
-/// triggers"); the controller code turns it into a DualSense trigger effect.
+/// What a trigger feels like on a DualSense, from what its action is doing (docs/controllers.md
+/// "Adaptive triggers" for the choices). Only the pad's official modes: Nielk1's notes warn the
+/// others may leave the firmware.
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub enum TriggerFeel {
    Free,
@@ -1543,6 +1544,66 @@ pub enum TriggerFeel {
    /// Mining a block of this hardness: a buzz, stronger and slower on harder blocks.
    Texture(f32),
 }
+#[cfg(feature = "controllers")]
+impl TriggerFeel {
+    /// The effect, for a trigger that presses its action at `threshold` (0..1) of its travel.
+    pub fn effect(self, threshold: f32) -> horizon_dualsense::TriggerEffect {
+        use horizon_dualsense::trigger;
+        // The zone (of ten along the travel) where the action presses: a catch gives way there,
+        // so the click and the shot coincide.
+        let press = ((threshold.clamp(0.0, 1.0) * 10.0) as u8).clamp(3, 8);
+        match self {
+            TriggerFeel::Free => horizon_dualsense::TRIGGER_OFF,
+            // From the third zone, so the press itself stays light; at most 6 of 8, as the
+            // draw is held.
+            TriggerFeel::Draw(charge) => {
+                trigger::feedback(2, 1 + (5.0 * charge.clamp(0.0, 1.0)).round() as u8)
+            }
+            TriggerFeel::Click => trigger::weapon((press - 2).max(2), press, 8),
+            TriggerFeel::Boost => trigger::weapon((press - 2).max(2), press, 5),
+            TriggerFeel::Brace => trigger::feedback(2, 3),
+            TriggerFeel::Locked => trigger::feedback(1, 8),
+            TriggerFeel::Texture(hardness) if hardness > 0.0 => {
+                // Dirt 2, stone 3, deepslate 4, obsidian 5 of 8.
+                let amplitude = (1.0 + 1.6 * hardness.sqrt()).round().clamp(1.0, 5.0);
+                // Sand and dirt a fine 40 Hz grit; stone 30; wood, deepslate and ores 20;
+                // obsidian a 10 Hz chisel.
+                let hertz = match hardness {
+                    h if h < 1.0 => 40,
+                    h if h < 2.0 => 30,
+                    h if h < 5.0 => 20,
+                    _ => 10,
+                };
+                trigger::vibration(1, amplitude as u8, hertz)
+            }
+            TriggerFeel::Texture(_) => horizon_dualsense::TRIGGER_OFF,
+        }
+    }
+}
+#[cfg(feature = "controllers")]
+impl PadSettings {
+    /// The left and right triggers' effects: each feels the action bound to it, `key.use` or
+    /// `key.attack`.
+    pub fn trigger_effects(
+        &self,
+        using: TriggerFeel,
+        attacking: TriggerFeel,
+    ) -> [horizon_dualsense::TriggerEffect; 2] {
+        [Button::LeftTrigger, Button::RightTrigger].map(|trigger| {
+            let actions = self.actions_of(trigger);
+            let feel = if !self.adaptive_triggers {
+                TriggerFeel::Free
+            } else if actions.contains(&"key.use") {
+                using
+            } else if actions.contains(&"key.attack") {
+                attacking
+            } else {
+                TriggerFeel::Free
+            };
+            feel.effect(self.trigger_threshold)
+        })
+    }
+}
 /// What a DualSense's lightbar shows (`lightbar:`).
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum Lightbar {
@@ -2377,6 +2438,52 @@ bind_key.hotbar.2:north
        assert_eq!(w.observe(Some(1.0)), Some(1.0));
    }

+    #[cfg(feature = "controllers")]
+    #[test]
+    fn triggers_feel_their_action() {
+        use horizon_dualsense::{TRIGGER_OFF, trigger};
+        let mut s = PadSettings::default();
+        // Use is LT, attack RT by default.
+        let [left, right] = s.trigger_effects(TriggerFeel::Draw(1.0), TriggerFeel::Texture(1.5));
+        assert_eq!(left, trigger::feedback(2, 6));
+        assert_eq!(right, trigger::vibration(1, 3, 30));
+        assert_eq!(
+            s.trigger_effects(TriggerFeel::Draw(0.0), TriggerFeel::Free),
+            [trigger::feedback(2, 1), TRIGGER_OFF]
+        );
+        // The catch gives way in the zone where the default threshold (0.4) presses: weapon
+        // 0x25, zones 2 and 4, strength 8 (stored 7) or 5 (stored 4).
+        let catch = |strength| [0x25, 0x14, 0x00, strength, 0, 0, 0, 0, 0, 0, 0];
+        assert_eq!(TriggerFeel::Click.effect(0.4), catch(7));
+        assert_eq!(TriggerFeel::Boost.effect(0.4), catch(4));
+        // A deeper threshold moves it: zones 5 and 7.
+        assert_eq!(TriggerFeel::Click.effect(0.7)[1..3], [0xa0, 0x00]);
+        assert_eq!(TriggerFeel::Click.effect(0.1), trigger::weapon(2, 3, 8));
+        assert_eq!(TriggerFeel::Brace.effect(0.4), trigger::feedback(2, 3));
+        assert_eq!(TriggerFeel::Locked.effect(0.4), trigger::feedback(1, 8));
+        // Harder blocks buzz harder and slower; instant-break blocks don't.
+        assert_eq!(
+            TriggerFeel::Texture(0.5).effect(0.4),
+            trigger::vibration(1, 2, 40)
+        );
+        assert_eq!(
+            TriggerFeel::Texture(3.0).effect(0.4),
+            trigger::vibration(1, 4, 20)
+        );
+        assert_eq!(
+            TriggerFeel::Texture(50.0).effect(0.4),
+            trigger::vibration(1, 5, 10)
+        );
+        assert_eq!(TriggerFeel::Texture(0.0).effect(0.4), TRIGGER_OFF);
+        assert_eq!(TriggerFeel::Texture(-1.0).effect(0.4), TRIGGER_OFF);
+        s.adaptive_triggers = false;
+        assert_eq!(
+            s.trigger_effects(TriggerFeel::Click, TriggerFeel::Boost),
+            [TRIGGER_OFF; 2]
+        );
+        assert!(!PadSettings::parse(&s.serialize()).adaptive_triggers);
+    }
+
    #[test]
    fn lightbar_colours() {
        let full = Lightbar::Health.colour(1.0, "minecraft:overworld").unwrap();
@@ -670,39 +670,6 @@ pub fn with_horizon_icon(
    attributes
 }

-/// The screen a window is on: its size in physical pixels, its refresh rate where the OS gives
-/// it, and its scale. For `horizon-ctl status` and the performance statistics' `system.display`.
-#[derive(Clone, Copy, Debug, PartialEq)]
-pub struct Display {
-    pub width: u32,
-    pub height: u32,
-    pub refresh_hz: Option<u32>,
-    pub scale: f64,
-}
-
-/// The screen `window` is on, else the primary one, else the only one: right after the window
-/// is made, Wayland doesn't say yet which screen it is on.
-pub fn monitor(window: &winit::window::Window) -> Option<winit::monitor::MonitorHandle> {
-    let only = || {
-        let mut all = window.available_monitors();
-        all.next().filter(|_| all.next().is_none())
-    };
-    window
-        .current_monitor()
-        .or_else(|| window.primary_monitor())
-        .or_else(only)
-}
-
-/// [`monitor`]'s size, refresh rate and scale.
-pub fn display(window: &winit::window::Window) -> Option<Display> {
-    monitor(window).map(|m| Display {
-        width: m.size().width,
-        height: m.size().height,
-        refresh_hz: m.refresh_rate_millihertz().map(|r| r.div_ceil(1000)),
-        scale: m.scale_factor(),
-    })
-}
-
 #[cfg(test)]
 mod tests {
    use super::*;
@@ -18,10 +18,10 @@ horizon-client-core = { path = "../horizon-client-core" }
 horizon-client-input = { path = "../horizon-client-input" }
 horizon-client-render = { path = "../horizon-client-render" }
 horizon-command = { path = "../horizon-command" }
+# Emotes pose the player model (`Mob::emote`, `mobs::anim::setup`).
+horizon-cosmetics = { path = "../horizon-cosmetics" }
 horizon-items = { path = "../horizon-items" }
 horizon-core = { path = "../horizon-core" }
-# Extension points for the crates above the engine (docs/layers.md, "How a Horizon crate plugs in").
-horizon-hooks = { path = "../horizon-hooks" }
 # `horizon-ctl mcp`: the Model Context Protocol, shared with the launcher and the server.
 horizon-mcp = { path = "../horizon-mcp" }
 # The server thread ahead of the workers (MinecraftServer.spin's Thread.setPriority).
@@ -42,6 +42,8 @@ horizon-chat-filter = { path = "../horizon-chat-filter" }
 horizon-shaders = { path = "../horizon-shaders" }
 # Horizon's own shader packs: the format, the stages and the check (docs/shaders.md).
 horizon-shader-api = { path = "../horizon-shader-api" }
+# Play with Friends: invite codes and their tunnel; the `friends` feature.
+horizon-friends = { path = "../horizon-friends", optional = true }
 # The narrator (GameNarrator): text-to-speech of chat, system messages and screens.
 horizon-narrator = { path = "../horizon-narrator" }
 # Horizon mods: sandboxed WebAssembly components, off unless installed and turned on (docs/mods.md).
@@ -71,13 +73,16 @@ mio = { version = "1.2.4", features = ["os-poll", "net"] }
 # Shared chunk frames are found by one keyed 128-bit hash of their body (lan/conn.rs SharedFrames).
 xxhash-rust = { version = "0.8.19", features = ["xxh3"] }
 horizon-theme = { path = "../horizon-theme" }
-# Opt-in data collection: the game keeps, the launcher sends (docs/telemetry.md).
+# Opt-in data collection: the game keeps, the launcher sends (docs/telemetry.md); `live` is
+# the anonymous "I'm playing" ping the game sends itself (`heartbeat.rs`), the `heartbeat` feature.
 horizon-telemetry = { path = "../horizon-telemetry", default-features = false }
 horizon-bench = { path = "../horizon-bench" }
 crc32fast = "1"
 zip = { version = "9.1.3", default-features = false, features = ["deflate"] }
 # Controllers (evdev + libudev on Linux, IOKit on macOS, Windows.Gaming.Input); the `controllers` feature.
 gilrs = { version = "0.11", optional = true }
+# The DualSense's rumble, adaptive triggers and lights over HID (gilrs only reads it).
+horizon-dualsense = { path = "../horizon-dualsense", optional = true }
 # HTTPS to the Minecraft services (online-mode session join).
 ureq = { version = "2", default-features = false, features = ["tls"] }
 unicode-bidi = "0.3.18"
@@ -109,17 +114,18 @@ objc2-foundation = { version = "0.3", default-features = false, features = ["std
 wgpu = { version = "30.0.1", default-features = false, features = ["gles"] }

 [features]
-default = ["audio", "controllers", "horizon-extras"]
+default = ["audio", "controllers", "discord", "friends", "heartbeat"]
 # Sound output. Without it (and `controllers`) the program links neither libasound nor libudev on
 # Linux: the server build (`--no-default-features`, released as horizon-engine; docs/server.md).
 audio = ["horizon-client-render/audio"]
 # Controllers: gilrs, and the DualSense's own output. Without it only `horizon-ctl pad`'s virtual pad.
-controllers = ["dep:gilrs", "horizon-client-input/controllers"]
-# Horizon's own parts (docs/forking.md, docs/layers.md): the features below, and the official
-# server in the list (`official_servers`).
-horizon-extras = ["discord"]
+controllers = ["dep:gilrs", "dep:horizon-dualsense", "horizon-client-input/controllers"]
 # "Playing Horizon" on the player's Discord profile (`discord_presence`).
 discord = []
+# Play with Friends, joining side (`net.rs`): without it no invite code joins.
+friends = ["dep:horizon-friends"]
+# The anonymous "I'm playing" ping (`heartbeat.rs`, docs/telemetry.md).
+heartbeat = ["horizon-telemetry/live"]
 # Records the call sites of mob random draws (`mob_ai_probe` traces).
 rng-trace = ["horizon-core/rng-trace"]
 # Compatibility with earlier experiment commands: main already uses mimalloc.
@@ -7,8 +7,6 @@ rust-version.workspace = true
 description = "The client's world data, rendering and screens: chunks, meshing, light, streaming, the renderer, the HUD, menus and settings; no gameplay"

 [dependencies]
-# The settings stores of the crates above the engine (docs/layers.md, "Platform registries").
-horizon-hooks = { path = "../horizon-hooks" }
 horizon-cosmetics = { path = "../horizon-cosmetics" }
 # The GUI atlas's pixels, kept compressed once uploaded (hud.rs `pack_pixels`).
 lz4_flex = { version = "0.14", default-features = false, features = ["std", "safe-encode", "safe-decode", "checked-decode"] }
@@ -26,6 +24,7 @@ horizon-narrator = { path = "../horizon-narrator" }
 horizon-optifine = { path = "../horizon-optifine" }
 horizon-polytone = { path = "../horizon-polytone" }
 horizon-protocol = { path = "../horizon-protocol" }
+horizon-render-pipeline = { path = "../horizon-render-pipeline" }
 horizon-shader-api = { path = "../horizon-shader-api" }
 horizon-shaders = { path = "../horizon-shaders" }
 horizon-system = { path = "../horizon-system" }
@@ -77,6 +76,9 @@ audio = ["dep:cpal"]
 # Helpers horizon-client's tests build their fixtures with.
 test-support = []

+[build-dependencies]
+horizon-mod-api-gen = { path = "../horizon-mod-api-gen" }
+
 [lints]
 workspace = true

@@ -0,0 +1,7 @@
+fn main() {
+    let root =
+        std::path::PathBuf::from(std::env::var_os("CARGO_MANIFEST_DIR").unwrap()).join("../..");
+    let out_dir = std::path::PathBuf::from(std::env::var_os("OUT_DIR").unwrap());
+    horizon_mod_api_gen::generate(&root, &out_dir, horizon_mod_api_gen::Target::Render)
+        .expect("generating native render mod API");
+}
@@ -16,45 +16,6 @@ use crate::{
 #[path = "chat_tests.rs"]
 mod tests;

-/// `FilterMask.applyWithFormatting` over a player message's signed content, as
-/// the packet's mask `(type, bit set)`: as it is when passed through, none when
-/// fully filtered, and when partly filtered each masked UTF-16 unit becomes a
-/// `#` in `FILTERED_STYLE` (dark grey, hover "chat.filtered").
-pub fn filtered_message(
-    content: &str,
-    (kind, bits): &(i32, Vec<i64>),
-) -> Option<serde_json::Value> {
-    match kind {
-        1 => return None,
-        2 => {}
-        _ => return Some(serde_json::Value::from(content)),
-    }
-    let masked = |i: usize| {
-        bits.get(i / 64)
-            .is_some_and(|w| (*w as u64 >> (i % 64)) & 1 != 0)
-    };
-    let units: Vec<u16> = content.encode_utf16().collect();
-    let mut parts = Vec::new();
-    let mut start = 0;
-    while start < units.len() {
-        let filtered = masked(start);
-        let end = (start..units.len())
-            .find(|&i| masked(i) != filtered)
-            .unwrap_or(units.len());
-        parts.push(if filtered {
-            serde_json::json!({
-                "text": "#".repeat(end - start),
-                "color": "dark_gray",
-                "hover_event": {"action": "show_text", "value": {"translate": "chat.filtered"}},
-            })
-        } else {
-            serde_json::Value::from(String::from_utf16_lossy(&units[start..end]))
-        });
-        start = end;
-    }
-    Some(serde_json::json!({"text": "", "extra": parts}))
-}
-
 /// `CommandHistory.PERSISTED_COMMANDS_FILE_NAME` and its size cap.
 const COMMAND_HISTORY_FILE: &str = "command_history.txt";
 const MAX_PERSISTED_COMMAND_HISTORY: usize = 50;
@@ -1026,43 +1026,3 @@ fn a_compact_repeat_keeps_the_scrolled_view_still() {
    says(&mut chat, "new");
    assert_eq!(chat.scroll, 6);
 }
-
-/// `FilterMask.applyWithFormatting`: a pass-through mask keeps the message, a
-/// fully filtered one hides it, and a partial one turns each masked UTF-16 unit
-/// into a dark grey `#` whose hover reads `chat.filtered`.
-#[test]
-fn a_server_filter_mask_hides_or_masks_the_message() {
-    let text = |v: &serde_json::Value| crate::component::to_text(v, &mut |s| Text::literal(s));
-    let shown = |content: &str, mask: (i32, Vec<i64>)| {
-        filtered_message(content, &mask).map(|v| text(&v).plain())
-    };
-    assert_eq!(shown("hello", (0, vec![])), Some("hello".to_owned()));
-    assert_eq!(shown("hello", (1, vec![])), None);
-    assert_eq!(shown("hello", (2, vec![0b0110])), Some("h##lo".to_owned()));
-    assert_eq!(
-        shown("hello", (2, vec![0b1_0001])),
-        Some("#ell#".to_owned())
-    );
-    // An emoji is two UTF-16 units, so two bits and two `#`.
-    assert_eq!(
-        shown("a\u{1F600}b", (2, vec![0b0110])),
-        Some("a##b".to_owned())
-    );
-    // Bit 65 is in the second word.
-    let long = "x".repeat(70);
-    let mut expected = long.clone();
-    expected.replace_range(65..66, "#");
-    assert_eq!(shown(&long, (2, vec![0, 0b10])), Some(expected));
-    let masked = text(&filtered_message("hello", &(2, vec![0b0110])).unwrap());
-    let hash = masked.spans.iter().find(|s| s.text == "##").unwrap();
-    assert_eq!(hash.style.color, Some(text::DARK_GRAY));
-    let hover = hash.style.hover.as_ref().unwrap();
-    assert_eq!(hover.spans[0].text, "chat.filtered");
-    assert!(
-        masked
-            .spans
-            .iter()
-            .filter(|s| s.text != "##")
-            .all(|s| s.style.color.is_none())
-    );
-}
@@ -121,8 +121,8 @@ impl CommandBlock {
            condition_met: flag("conditionMet", false),
        }
    }
-    /// `CommandBlockEntity.saveAdditional`. The last output is the component
-    /// itself (`ComponentSerialization.CODEC`), styles and click events kept.
+    /// `CommandBlockEntity.saveAdditional`. The last output is written as a
+    /// plain string component.
    pub fn save(&self) -> Vec<(&'static str, Tag)> {
        let mut out = vec![
            ("Command", Tag::String(self.command.as_str().into())),
@@ -135,7 +135,7 @@ impl CommandBlock {
        if self.track_output
            && let Some(last) = &self.last_output
        {
-            out.push(("LastOutput", scoreboard::component_tag(&last.component())));
+            out.push(("LastOutput", Tag::String(last.plain().as_str().into())));
        }
        out.push((
            "UpdateLastExecution",
@@ -43,11 +43,6 @@ pub fn enter_native_mod(call: NativeModCall) -> NativeModGuard {
    }
 }

-/// The native mod call this thread is currently inside, if any.
-pub fn current_native_mod() -> Option<NativeModCall> {
-    IN_NATIVE_MOD.with(Cell::get)
-}
-
 /// Puts back the call that `enter_native_mod` found.
 #[must_use]
 pub struct NativeModGuard {
@@ -249,7 +244,7 @@ fn arch_label(build: &str, machine: &str) -> String {
 }

 /// `PRETTY_NAME` of /etc/os-release and the kernel, or the system's own version string.
-pub(crate) fn operating_system() -> String {
+fn operating_system() -> String {
    let arch = arch_label(std::env::consts::ARCH, machine_arch());
    let version = if cfg!(target_os = "linux") {
        let name = read("/etc/os-release").and_then(|t| {
@@ -1,34 +1,27 @@
-//! Custom sky layers: skyboxes a pack draws over the vanilla sky, in a format vanilla doesn't read
-//! (OptiFine's), which the platform's pack formats fill ([`crate::pack_hooks`]). The layers'
-//! textures are read once with the pack; each frame the game asks for the layers to draw, their
-//! brightness and rotation ([`SkyLayers::draws`]), and `gfx::custom_sky` draws them over the
-//! vanilla sky. A pack without layers keeps the vanilla sky.
+//! OptiFine custom skies (`horizon_optifine::sky`) as the game draws them: a pack's layers with
+//! their decoded textures, read once with the pack, and each frame's choice of layers, their
+//! brightness and rotation ([`CustomSky::draws`]), which `gfx::custom_sky` draws over the
+//! vanilla sky. A pack without `optifine/sky` gives an empty [`CustomSky`] and the sky stays
+//! vanilla.

 use std::path::Path;
-use std::sync::Arc;

-use glam::Mat4;
+use glam::{Mat4, Vec3};
+use horizon_optifine::sky::{Blend, Conditions, Skies, SkyLayer, Transition};

-/// A layer's texture, RGBA8: the skybox's six faces in a 3x2 grid, bottom, top and south in the
-/// top row, west, north and east below (`gfx::custom_sky`'s faces).
+/// A layer's texture, RGBA8.
 pub struct Image {
    pub width: u32,
    pub height: u32,
    pub rgba: Vec<u8>,
 }

-/// How a layer mixes with what is drawn below it.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum Blend {
-    Add,
-    Subtract,
-    Multiply,
-    Dodge,
-    Burn,
-    Screen,
-    Replace,
-    Overlay,
-    Alpha,
+/// The pack's layers, by world, with one texture per layer (`images[i]` for the `i`th layer
+/// over all worlds, in `worlds` order).
+#[derive(Default)]
+pub struct CustomSky {
+    worlds: Vec<(i32, Vec<SkyLayer>)>,
+    pub images: Vec<Image>,
 }

 /// One layer of a frame: which texture, with which blend, how bright and turned how.
@@ -41,44 +34,62 @@ pub struct Draw {
    pub rotation: Mat4,
 }

-/// The weather of a frame: thunder is a storm's rain, so it is only `Thunder`.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum Weather {
-    Clear,
-    Rain,
-    Thunder,
-}
-
-/// What a frame's layers may depend on.
-#[derive(Clone, Copy, Debug)]
-pub struct Conditions<'a> {
-    /// Ticks of the day, counting the days.
-    pub day_time: i64,
-    pub weather: Weather,
-    /// The biome at the camera, namespaced.
-    pub biome: &'a str,
-    /// The camera's block height.
-    pub y: i32,
-}
-
 /// The eased brightness of each layer, kept by the game between frames.
 #[derive(Default)]
 pub struct State {
-    /// The world the layers were last drawn for.
-    pub world: Option<i32>,
-    /// Each layer's eased visibility, 0 to 1.
-    pub eased: Vec<f32>,
+    world: Option<i32>,
+    eased: Vec<Transition>,
 }

-/// A pack's custom sky layers, by world (`0` the Overworld, `1` the End).
-pub trait SkyLayers: Send + Sync {
-    /// Every layer's texture: [`Draw::image`] indexes it.
-    fn images(&self) -> &[Image];
-    /// Whether `world` has layers.
-    fn has(&self, world: i32) -> bool;
-    /// This frame's layers of `world` into `out` (cleared first), in drawing order, eased by
-    /// `seconds` since the last frame. `sun_turns` is the sun's angle over 360° (`0` at noon).
-    fn draws(
+/// Textures past this many texels in all are left out (a skybox is a few megapixels at most).
+const TEXEL_BUDGET: u64 = 64 << 20;
+
+impl CustomSky {
+    /// The custom skies of the overlay at `root`. A layer whose texture does not decode is
+    /// dropped with a warning.
+    pub fn load(root: &Path) -> Self {
+        let skies = Skies::scan(root);
+        let mut out = Self::default();
+        let mut texels = 0u64;
+        for (world, sky) in skies.worlds {
+            let mut layers = Vec::new();
+            for layer in sky.layers {
+                match crate::hud::decode(&root.join(&layer.source)) {
+                    Ok((width, height, rgba))
+                        if texels + u64::from(width) * u64::from(height) <= TEXEL_BUDGET =>
+                    {
+                        texels += u64::from(width) * u64::from(height);
+                        out.images.push(Image {
+                            width,
+                            height,
+                            rgba,
+                        });
+                        layers.push(layer);
+                    }
+                    Ok(_) => log::warn!("{}: past the custom sky's texture budget", layer.source),
+                    Err(e) => log::warn!("{}: {e:#}", layer.source),
+                }
+            }
+            if !layers.is_empty() {
+                out.worlds.push((world, layers));
+            }
+        }
+        out
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.worlds.is_empty()
+    }
+
+    /// Whether `world` has layers (`0` the Overworld, `1` the End).
+    pub fn has(&self, world: i32) -> bool {
+        self.worlds.iter().any(|(w, _)| *w == world)
+    }
+
+    /// This frame's layers of `world` into `out` (cleared first), in drawing order: those whose
+    /// conditions hold, eased over their `transition` by `seconds` since the last frame, at the
+    /// brightness of their fade times. `sun_turns` is the sun's angle over 360° (`0` at noon).
+    pub fn draws(
        &self,
        world: i32,
        conditions: &Conditions,
@@ -86,30 +97,147 @@ pub trait SkyLayers: Send + Sync {
        seconds: f32,
        state: &mut State,
        out: &mut Vec<Draw>,
-    );
-}
-
-/// No layers: the vanilla sky.
-struct NoLayers;
-
-impl SkyLayers for NoLayers {
-    fn images(&self) -> &[Image] {
-        &[]
-    }
-
-    fn has(&self, _: i32) -> bool {
-        false
-    }
-
-    fn draws(&self, _: i32, _: &Conditions, _: f32, _: f32, s: &mut State, out: &mut Vec<Draw>) {
+    ) {
        out.clear();
-        s.world = None;
+        let mut first = 0;
+        let mut found = None;
+        for (w, layers) in &self.worlds {
+            if *w == world {
+                found = Some(layers);
+                break;
+            }
+            first += layers.len();
+        }
+        let Some(layers) = found else {
+            state.world = None;
+            return;
+        };
+        // A new world (or pack) starts each layer where its conditions put it: no fade in.
+        let snap = state.world != Some(world) || state.eased.len() != layers.len();
+        if snap {
+            state.world = Some(world);
+            state.eased.clear();
+            state.eased.resize(layers.len(), Transition::default());
+        }
+        for (i, (layer, eased)) in layers.iter().zip(&mut state.eased).enumerate() {
+            let target = if layer.shows(conditions) { 1.0 } else { 0.0 };
+            let shown = if snap {
+                eased.value = target;
+                target
+            } else {
+                eased.step(target, seconds, layer.transition)
+            };
+            let brightness = shown * layer.brightness(conditions.day_time);
+            if brightness <= 0.0 {
+                continue;
+            }
+            let turns = layer.turns(conditions.day_time, sun_turns);
+            let rotation = if turns == 0.0 {
+                Mat4::IDENTITY
+            } else {
+                Mat4::from_axis_angle(Vec3::from_array(layer.axis), turns * std::f32::consts::TAU)
+            };
+            out.push(Draw {
+                image: (first + i) as u16,
+                blend: layer.blend,
+                brightness,
+                rotation,
+            });
+        }
    }
 }

-/// The custom sky layers of the overlay at `root`, from the installed pack formats.
-pub fn load(root: &Path) -> Arc<dyn SkyLayers> {
-    crate::pack_hooks::formats()
-        .custom_sky(root)
-        .unwrap_or_else(|| Arc::new(NoLayers))
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use horizon_optifine::sky::Now;
+
+    fn pack(files: &[(&str, &str)]) -> (std::path::PathBuf, CustomSky) {
+        let root = std::env::temp_dir().join(format!(
+            "horizon-custom-sky-{}-{}",
+            std::process::id(),
+            files.len()
+        ));
+        let _ = std::fs::remove_dir_all(&root);
+        let dir = root.join("assets/minecraft/optifine/sky/world0");
+        std::fs::create_dir_all(&dir).unwrap();
+        let png = {
+            let mut bytes = Vec::new();
+            let mut encoder = png::Encoder::new(&mut bytes, 6, 4);
+            encoder.set_color(png::ColorType::Rgba);
+            encoder.set_depth(png::BitDepth::Eight);
+            let mut writer = encoder.write_header().unwrap();
+            writer
+                .write_image_data(&[255, 0, 0, 255].repeat(24))
+                .unwrap();
+            writer.finish().unwrap();
+            bytes
+        };
+        for (name, text) in files {
+            std::fs::write(dir.join(format!("{name}.properties")), text).unwrap();
+            std::fs::write(dir.join(format!("{name}.png")), &png).unwrap();
+        }
+        let sky = CustomSky::load(&root);
+        (root, sky)
+    }
+
+    fn noon(biome: &str) -> Conditions<'_> {
+        Conditions {
+            day_time: 6000,
+            weather: Now::Clear,
+            biome,
+            y: 64,
+        }
+    }
+
+    #[test]
+    fn layers_ease_in_at_a_biome_border_but_not_on_arrival() {
+        let (root, sky) = pack(&[
+            ("sky1", "biomes=desert\ntransition=2"),
+            ("sky2", "blend=alpha\nrotate=false"),
+        ]);
+        let _ = std::fs::remove_dir_all(root);
+        assert!(sky.has(0) && !sky.has(1));
+        assert_eq!(sky.images[0].width, 6);
+        let (mut state, mut out) = (State::default(), Vec::new());
+        sky.draws(
+            0,
+            &noon("minecraft:desert"),
+            0.0,
+            0.05,
+            &mut state,
+            &mut out,
+        );
+        assert_eq!(
+            out.iter().map(|d| d.brightness).collect::<Vec<_>>(),
+            [1.0, 1.0]
+        );
+        // Out of the desert: the first layer fades over its two seconds.
+        sky.draws(0, &noon("minecraft:plains"), 0.0, 0.5, &mut state, &mut out);
+        assert_eq!(out[0].brightness, 0.75);
+        assert_eq!(out[1].blend, Blend::Alpha);
+        sky.draws(0, &noon("minecraft:plains"), 0.0, 2.0, &mut state, &mut out);
+        assert_eq!(out.len(), 1, "a dark layer is not drawn");
+        assert_eq!(out[0].image, 1);
+        // Into the End, which has no layers, and back: no fade.
+        sky.draws(1, &noon("minecraft:desert"), 0.0, 0.0, &mut state, &mut out);
+        assert!(out.is_empty());
+        sky.draws(0, &noon("minecraft:desert"), 0.0, 0.0, &mut state, &mut out);
+        assert_eq!(out.len(), 2);
+    }
+
+    #[test]
+    fn a_layer_turns_west_like_the_sun() {
+        let (root, sky) = pack(&[("sky1", "")]);
+        let _ = std::fs::remove_dir_all(root);
+        let (mut state, mut out) = (State::default(), Vec::new());
+        // A quarter turn after noon (sunset): the skybox's zenith has gone down to the west.
+        let c = Conditions {
+            day_time: 12000,
+            ..noon("minecraft:plains")
+        };
+        sky.draws(0, &c, 0.25, 0.0, &mut state, &mut out);
+        let up = out[0].rotation.transform_vector3(Vec3::Y);
+        assert!((up - Vec3::NEG_X).length() < 1e-5, "{up}");
+    }
 }
@@ -305,9 +305,6 @@ pub(crate) struct Colormap {
    /// (`temperature`, `downfall`, `biome_id`) blend: Polytone 6.8.6's water by `biome_id`
    /// fades over a biome edge.
    pub(crate) biome_blend: bool,
-    /// Its axes read nothing that changes up a column of one biome (no `o.y`): a section of
-    /// one biome can sample it once per column.
-    pub(crate) column: bool,
    width: u32,
    height: u32,
    rgba: Vec<u8>,
@@ -326,18 +323,6 @@ enum Axis {
 }

 impl Axis {
-    /// Whether the axis reads only what stays the same up a column of one biome.
-    fn column(&self) -> bool {
-        use horizon_polytone::expr::Root;
-        let flat = |root: Root, name: &str| match root {
-            Root::Object => matches!(name, "x" | "z" | "biome" | "temperature" | "downfall"),
-            Root::Random => name == "noise",
-            _ => false,
-        };
-        match self {
-            Self::Expr(program) | Self::BiomeId(_, program) => program.reads_only(&flat),
-        }
-    }
    fn value(&self, host: &mut dyn horizon_polytone::expr::Host) -> Option<f64> {
        match self {
            Self::Expr(program) => Some(program.eval(host).ok()?.num()),
@@ -388,23 +373,6 @@ fn biome_id_mapper(pack_root: &Path, json: &Json) -> HashMap<String, f64> {
 }

 impl Colormap {
-    /// One colour wherever it samples (a `biome_colors` flat colour, RGB).
-    pub(crate) fn flat(rgb: u32) -> Self {
-        let zero = || Axis::Expr(horizon_polytone::expr::Program::compile("0").expect("a number"));
-        let [_, r, g, b] = rgb.to_be_bytes();
-        Self {
-            x: zero(),
-            y: zero(),
-            triangular: false,
-            rounds: true,
-            biome_blend: false,
-            column: true,
-            width: 1,
-            height: 1,
-            rgba: vec![r, g, b, 255],
-        }
-    }
-
    /// `assets/<namespace>/polytone/colormaps/<path>.png` and its optional `.json` (without
    /// one, the axes are the biome's temperature and downfall).
    pub(crate) fn load(pack_root: &Path, id: &str) -> Option<Self> {
@@ -456,11 +424,9 @@ impl Colormap {
            axis("x_axis", "o.temperature")?,
            axis("y_axis", "o.downfall")?,
        );
-        let column = [&x, &y].iter().all(|axis| axis.column());
        Some(Self {
            x,
            y,
-            column,
            biome_blend: json["biome_blend"].as_bool().unwrap_or(by_biome),
            triangular: json["triangular"].as_bool() == Some(true),
            rounds: json["rounds"].as_bool() != Some(false),
@@ -482,16 +482,13 @@ impl Extras {
        true
    }
    /// Written only once something differs from the defaults, so a vanilla
-    /// setup gains no file. The settings stores of this file follow these lines
-    /// (`horizon_hooks::settings`).
+    /// setup gains no file.
    pub fn save(&self, dir: &Path) {
        let path = dir.join(FILE);
-        let mut text = self.serialize();
-        let stores_default = horizon_hooks::settings::engine::append(FILE, &mut text);
-        if *self == Self::default() && stores_default && !path.exists() {
+        if *self == Self::default() && !path.exists() {
            return;
        }
-        let _ = fs::write(path, text);
+        let _ = fs::write(path, self.serialize());
    }
 }

@@ -1,6 +1,5 @@
 //! The Horizon Extras page, on the settings shell (`settings_shell`): which rows it has and what
-//! pressing them does. Each one's value and what it does stay in `extras::Item`; the sections crates
-//! add (`horizon_hooks::pages::Place::Extras`) keep theirs.
+//! pressing them does. Each one's value and what it does stay in `extras::Item`.
 use crate::{
    extras::{self, Item},
    lang,
@@ -8,7 +7,6 @@ use crate::{
    settings::Settings,
    settings_shell::{self as shell, Binding, Group, Output, Row, Screen, Sheet, Value},
 };
-use horizon_hooks::pages::{self as added, Act, Label};

 const TITLE: &str = "horizon.pages.extras";
 const ABOUT: &str = "horizon.pages.extras.tooltip";
@@ -33,121 +31,6 @@ pub(crate) enum ExtraRow {
    /// It isn't installed: where to get it. A note, not a button: Options > Mods already has the
    /// one way into the Mods page (`every_setting_and_page_is_reached_from_one_place`).
    ZoomInstall,
-    /// Row `.1` of the section registered page `.0` adds (`Place::Extras`).
-    Added(usize, usize),
-}
-
-#[cfg(test)]
-thread_local! {
-    /// A test's own pages, instead of the game's registered ones: each test runs on its thread.
-    static TEST_PAGES: std::cell::Cell<Option<&'static [&'static dyn added::Page]>> =
-        const { std::cell::Cell::new(None) };
-}
-
-/// The pages crates registered, all places.
-fn pages() -> &'static [&'static dyn added::Page] {
-    #[cfg(test)]
-    if let Some(pages) = TEST_PAGES.get() {
-        return pages;
-    }
-    added::engine::all()
-}
-
-/// The sections of this page, by their index among the registered pages.
-fn sections() -> impl Iterator<Item = (usize, &'static dyn added::Page)> {
-    let pages = pages().iter().copied().enumerate();
-    pages.filter(|(_, page)| page.place() == added::Place::Extras)
-}
-
-fn label_text(label: Label) -> String {
-    match label {
-        Label::Key(key) => lang::get(key),
-        Label::Value(text) => text,
-    }
-}
-
-/// The page's group named `name`, made at the end if it has none.
-fn group_named<'a>(
-    groups: &'a mut Vec<Group<ExtraRow>>,
-    name: &'static str,
-) -> &'a mut Group<ExtraRow> {
-    let at = groups.iter().position(|group| group.name == name);
-    let at = at.unwrap_or_else(|| {
-        groups.push(Group {
-            name,
-            rows: Vec::new(),
-        });
-        groups.len() - 1
-    });
-    &mut groups[at]
-}
-
-/// The sections' rows, in the groups their titles and headings name.
-fn add_sections(groups: &mut Vec<Group<ExtraRow>>) {
-    for (page, section) in sections() {
-        let mut rows = Vec::new();
-        section.rows(&mut rows);
-        let mut name = section.title();
-        for (r, row) in rows.into_iter().enumerate() {
-            let id = ExtraRow::Added(page, r);
-            let row = match row {
-                added::Row::Heading(key) => {
-                    name = key;
-                    continue;
-                }
-                added::Row::Note(text) => Row::new(id, text, Value::Note).live(false),
-                added::Row::Toggle { label, on } => {
-                    Row::new(id, lang::get(label), Value::Switch(on))
-                }
-                added::Row::Cycle { label, value } => {
-                    Row::new(id, lang::get(label), Value::Choice(label_text(value)))
-                }
-                added::Row::Slider { label, value, text } => {
-                    let position = value.clamp(0.0, 1.0);
-                    let text = label_text(text);
-                    let value = Value::Slider {
-                        position,
-                        steps: None,
-                        text,
-                    };
-                    Row::new(id, lang::get(label), value)
-                }
-                added::Row::Button { label } => Row::new(id, lang::get(label), Value::Press),
-                added::Row::Key { label, key } => {
-                    let key = crate::keybinds::display_name(&key).plain();
-                    Row::new(id, lang::get(label), Value::Read(key))
-                }
-                // A row kind newer than this engine.
-                _ => continue,
-            };
-            let row = match section.tooltip(r) {
-                Some(about) => row.about(label_text(about)),
-                None => row,
-            };
-            group_named(groups, name).rows.push(row);
-        }
-    }
-}
-
-/// Row `r` of registered page `page` was acted on: the options screen saves when it closes.
-fn act(page: usize, r: usize, act: Act) -> Vec<Output> {
-    let Some(section) = pages().get(page) else {
-        return Vec::new();
-    };
-    section.act(r, act);
-    vec![Output::Event(Event::Changed)]
-}
-
-/// Whether row `r` of registered page `page` steps (a switch or a cycle).
-fn steps(page: usize, r: usize) -> bool {
-    let mut rows = Vec::new();
-    if let Some(section) = pages().get(page) {
-        section.rows(&mut rows);
-    }
-    matches!(
-        rows.get(r),
-        Some(added::Row::Toggle { .. } | added::Row::Cycle { .. })
-    )
 }

 fn item_row(item: Item, s: &Settings) -> Row<ExtraRow> {
@@ -202,14 +85,9 @@ impl Screen for ExtrasScreen {
    fn note_lines(&self) -> usize {
        NOTE_LINES
    }
-    /// The rows read the extras, the mods, whether cosmetics are offered and the sections' rows.
+    /// The rows read the extras, the mods and whether cosmetics are offered.
    fn stamp(&self, s: &Settings) -> u64 {
-        let mut added = Vec::new();
-        for (_, section) in sections() {
-            section.rows(&mut added);
-        }
-        let cosmetics = horizon_cosmetics::enabled();
-        shell::stamp_of(&(&s.extras, &s.mods, cosmetics, added))
+        shell::stamp_of(&(&s.extras, &s.mods, horizon_cosmetics::enabled()))
    }
    fn sheets(&self, s: &Settings) -> Vec<Sheet<(), ExtraRow>> {
        let mut groups = vec![Group {
@@ -229,7 +107,6 @@ impl Screen for ExtrasScreen {
                }
            }
        }
-        add_sections(&mut groups);
        vec![Sheet::new((), lang::get(TITLE), lang::get(ABOUT), groups)]
    }
    fn press(&mut self, s: &mut Settings, row: ExtraRow, back: bool) -> Vec<Output> {
@@ -248,29 +125,16 @@ impl Screen for ExtrasScreen {
                Output::Event(Event::NativeSettings(i)),
            ],
            ExtraRow::ZoomInstall => Vec::new(),
-            ExtraRow::Added(page, r) => {
-                act(page, r, if back { Act::PressBack } else { Act::Press })
-            }
-        }
-    }
-    fn slide(&mut self, _s: &mut Settings, row: ExtraRow, position: f32) {
-        if let ExtraRow::Added(page, r) = row {
-            act(page, r, Act::Slide(position));
        }
    }
    /// With the wheel extra on, the wheel over an item changes it, without a click; the mod's rows
    /// let the list scroll.
    fn wheel_step(&mut self, s: &mut Settings, row: ExtraRow, back: bool) -> Option<Vec<Output>> {
-        match row {
-            ExtraRow::Item(item) => {
-                item.cycle(&mut s.extras, back);
-                Some(vec![Output::Event(Event::Changed)])
-            }
-            ExtraRow::Added(page, r) if steps(page, r) => {
-                Some(act(page, r, if back { Act::PressBack } else { Act::Press }))
-            }
-            _ => None,
-        }
+        let ExtraRow::Item(item) = row else {
+            return None;
+        };
+        item.cycle(&mut s.extras, back);
+        Some(vec![Output::Event(Event::Changed)])
    }
 }

@@ -428,148 +292,4 @@ mod tests {
        shell.key(&mut s, K::ArrowDown, None, false, size);
        assert_eq!(shell.focused_row(), Some(first));
    }
-
-    /// A section with a switch in the page's Multiplayer group, then a heading of its own with a
-    /// number that steps either way, a note and a volume.
-    struct Section {
-        on: std::sync::Mutex<bool>,
-        step: std::sync::Mutex<i32>,
-        volume: std::sync::Mutex<f32>,
-    }
-    impl added::Page for Section {
-        fn id(&self) -> &'static str {
-            "test.section"
-        }
-        fn title(&self) -> &'static str {
-            "horizon.extras.header.multiplayer"
-        }
-        fn place(&self) -> added::Place {
-            added::Place::Extras
-        }
-        fn rows(&self, rows: &mut Vec<added::Row>) {
-            rows.push(added::Row::Toggle {
-                label: "test.section.switch",
-                on: *self.on.lock().unwrap(),
-            });
-            rows.push(added::Row::Heading("test.section.heading"));
-            rows.push(added::Row::Cycle {
-                label: "test.section.step",
-                value: Label::Value(self.step.lock().unwrap().to_string()),
-            });
-            rows.push(added::Row::Note("a note".into()));
-            rows.push(added::Row::Slider {
-                label: "test.section.volume",
-                value: *self.volume.lock().unwrap(),
-                text: Label::Value(String::new()),
-            });
-        }
-        fn act(&self, row: usize, act: Act) {
-            match (row, act) {
-                (0, Act::Press | Act::PressBack) => {
-                    let mut on = self.on.lock().unwrap();
-                    *on = !*on;
-                }
-                (2, Act::Press) => *self.step.lock().unwrap() += 1,
-                (2, Act::PressBack) => *self.step.lock().unwrap() -= 1,
-                (4, Act::Slide(v)) => *self.volume.lock().unwrap() = v,
-                _ => {}
-            }
-        }
-    }
-
-    /// A page for Horizon Settings: never on Extras.
-    struct Elsewhere;
-    impl added::Page for Elsewhere {
-        fn id(&self) -> &'static str {
-            "test.elsewhere"
-        }
-        fn title(&self) -> &'static str {
-            "test.elsewhere"
-        }
-        fn place(&self) -> added::Place {
-            added::Place::HorizonSettings
-        }
-        fn rows(&self, rows: &mut Vec<added::Row>) {
-            rows.push(added::Row::Button {
-                label: "test.elsewhere.button",
-            });
-        }
-        fn act(&self, _: usize, _: Act) {}
-    }
-
-    fn with_section() -> &'static Section {
-        let section: &'static Section = Box::leak(Box::new(Section {
-            on: false.into(),
-            step: 0.into(),
-            volume: 0.5.into(),
-        }));
-        let pages: &'static [&'static dyn added::Page] = Box::leak(Box::new([
-            &Elsewhere as &dyn added::Page,
-            section as &dyn added::Page,
-        ]));
-        TEST_PAGES.set(Some(pages));
-        section
-    }
-
-    /// The section's first row joins the page's own Multiplayer group, after its rows; its heading
-    /// starts a group after the page's; a page for elsewhere adds nothing.
-    #[test]
-    fn a_section_joins_the_group_its_title_names_and_heads_its_own() {
-        with_section();
-        let s = Settings::default();
-        let sheets = ExtrasScreen.sheets(&s);
-        let groups = &sheets[0].groups;
-        let ids = |name: &str| -> Vec<ExtraRow> {
-            let group = groups.iter().find(|g| g.name == name).unwrap();
-            group.rows.iter().map(|r| r.id).collect()
-        };
-        let multiplayer = ids("horizon.extras.header.multiplayer");
-        assert_eq!(multiplayer.last(), Some(&ExtraRow::Added(1, 0)));
-        assert_eq!(groups.last().unwrap().name, "test.section.heading");
-        let own = [
-            ExtraRow::Added(1, 2),
-            ExtraRow::Added(1, 3),
-            ExtraRow::Added(1, 4),
-        ];
-        assert_eq!(ids("test.section.heading"), own);
-        let all = rows_of(&s);
-        assert!(!all.iter().any(|r| matches!(r.id, ExtraRow::Added(0, _))));
-    }
-
-    /// A click flips the switch, a Shift click steps the number back, the wheel steps it, and the
-    /// note takes no click; the rows show what the section holds after each.
-    #[test]
-    fn a_sections_rows_act_on_it() {
-        let section = with_section();
-        let mut s = Settings::default();
-        let mut shell = Shell::<ExtrasScreen>::default();
-        let switch = ExtraRow::Added(1, 0);
-        let at = shell.point_at(&s, SIZE, switch);
-        assert!(
-            !shell
-                .click(&mut s, at, SIZE, false, false, false)
-                .is_empty()
-        );
-        assert!(*section.on.lock().unwrap());
-        let value = |s: &Settings, id| rows_of(s).into_iter().find(|r| r.id == id).unwrap().value;
-        assert_eq!(value(&s, switch), Value::Switch(true));
-        let step = ExtraRow::Added(1, 2);
-        let mut screen = ExtrasScreen;
-        screen.press(&mut s, step, true);
-        assert_eq!(value(&s, step), Value::Choice("-1".into()));
-        assert!(screen.wheel_step(&mut s, step, false).is_some());
-        assert_eq!(*section.step.lock().unwrap(), 0);
-        assert_eq!(
-            screen.wheel_step(&mut s, ExtraRow::Added(1, 3), false),
-            None
-        );
-        let note = shell.point_at(&s, SIZE, ExtraRow::Added(1, 3));
-        assert!(
-            shell
-                .click(&mut s, note, SIZE, false, false, false)
-                .is_empty()
-        );
-        screen.slide(&mut s, ExtraRow::Added(1, 4), 0.25);
-        assert_eq!(*section.volume.lock().unwrap(), 0.25);
-    }
 }
@@ -179,7 +179,7 @@ fn packed_wanted() -> bool {
    std::env::var("HORIZON_PACKED_QUADS").as_deref() != Ok("0")
 }

-pub(crate) mod animate;
+mod animate;
 mod arena;
 pub mod capture;
 pub mod compositor;
@@ -194,7 +194,6 @@ mod frame_gen;
 mod gpu_culling;
 mod hdr;
 mod hdr_icc;
-mod hdr_start;
 mod hdr_stats;
 pub(crate) mod hud_coverage;
 pub use hdr::{Calibration as HdrCalibration, Output as HdrOutput};
@@ -216,7 +215,6 @@ mod occlusion;
 mod oit;
 mod oit_features;
 pub(crate) mod output;
-mod output_apply;
 mod pack_atlas;
 mod pack_center_depth;
 pub mod pack_draw;
@@ -1329,7 +1327,7 @@ pub struct Renderer {
    celestial_buffer: wgpu::Buffer,
    end_sky: end_sky::EndSky,
    stars: stars::Stars,
-    /// Custom sky layers (`crate::custom_sky`), and the frame's from the game.
+    /// OptiFine custom sky layers (`crate::custom_sky`), and the frame's from the game.
    custom_sky: custom_sky::CustomSky,
    custom_sky_draws: Vec<crate::custom_sky::Draw>,
    /// The glowing entities' outline (`LevelRenderer.entityOutlineTarget`).
@@ -1528,10 +1526,6 @@ pub struct Renderer {
    emission_stats: hdr_stats::EmissionStats,
    /// What this renderer's destination offers and its device draws.
    output_caps: output::OutputCapabilities,
-    /// An output that failed to apply, not tried again until something it needs changes.
-    output_rejected: Option<output_apply::Rejected>,
-    /// Since when Auto keeps HDR on through the display's loss of its report.
-    auto_off_since: Option<std::time::Instant>,
    /// The output applied (`update_output`), with the frame every pipeline that draws it
    /// targets: the swapchain's 8-bit format, or `Rgba16Unorm` when the renderer was made with
    /// HDR output on and Smooth Gradients and the device draws and blends into it, or
@@ -1544,8 +1538,6 @@ pub struct Renderer {
    /// The marker file of an HDR output that has not presented a frame yet
    /// (`graphics::HDR_MARKER`).
    hdr_marker: Option<std::path::PathBuf>,
-    /// The window's graphics driver (`hdr_start`); `None` offscreen.
-    hdr_driver: Option<String>,
    /// The HDR Lighting setting, kept for the HDR output made when HDR turns on.
    hdr_lighting_setting: bool,
    /// The shader pack's post-processing, and the dimension (legacy id) it was loaded for.
@@ -2993,13 +2985,11 @@ impl Renderer {
            adapter.get_downlevel_capabilities().flags,
            adapter.get_texture_format_features(hud_coverage::FORMAT),
        );
-        let hdr_driver = surface.is_some().then(|| output::window_driver(&info));
        let output_caps = output::OutputCapabilities {
            hdr: hdr_output,
            wide_frame: wide_ok,
            float_frame: float_ok,
            hud_layer: coverage_ok,
-            held: output::held(settings, hdr_driver.as_deref()),
        };
        let frame = output::resolve_frame(settings, request, output_caps, display, config.format);
        let (frame_format, hud_coverage, overlay_format) =
@@ -4249,13 +4239,16 @@ impl Renderer {
            CRUMBLING_BLEND,
            false,
        );
-        // RenderPipelines.ENTITY_SHADOW: translucent, back-face culled, depth test without writes.
-        // The quads lie exactly on the block tops like vanilla's, facing +Y so looking up from
-        // below culls them, but terrain and shadows are separate draw paths, so their fp32 depth
-        // interpolations disagree by a few dozen ulps of the fragment depth and the shadow's rim
-        // z-fights with the block top (speckle that re-rolls as the camera drifts a subpixel). A
-        // constant bias of 128 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.
+        // RenderPipelines.ENTITY_SHADOW: translucent, back-face culled, depth
+        // test without writes. The quads lie exactly on the block tops like
+        // vanilla's, facing +Y so looking up from below culls them, but
+        // terrain and shadows are separate draw paths, so their fp32 depth
+        // interpolations disagree by a few dozen ulps of the fragment depth
+        // and the shadow's rim z-fights with the block top (speckle that
+        // re-rolls as the camera drifts a subpixel). A constant bias of 128
+        // 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_with(
            "Entity shadows",
            Some(wgpu::Face::Back),
@@ -5353,13 +5346,10 @@ impl Renderer {
            hdr_lighting_setting: true,
            emission_stats,
            output_caps,
-            output_rejected: None,
-            auto_off_since: None,
            // Nothing is presented as HDR yet: `update_output` applies the settings.
            output: output::resolve_output(settings, output_caps, display, frame, false),
            frame_kept_logged: false,
            hdr_marker: None,
-            hdr_driver,
            pack_post: None,
            pack_loading: None,
            native: None,
@@ -5517,18 +5507,18 @@ impl Renderer {
            ))
        });
    }
-    /// The pack's custom sky layer textures (`crate::custom_sky::load`).
-    pub fn set_custom_sky(&mut self, pack: &dyn crate::custom_sky::SkyLayers) {
+    /// The pack's OptiFine custom sky layer textures (`crate::custom_sky::CustomSky::load`).
+    pub fn set_custom_sky(&mut self, pack: &crate::custom_sky::CustomSky) {
        self.custom_sky.set_pack(&self.device, &self.queue, pack);
    }
-    /// The custom sky layers the next frame draws (`SkyLayers::draws`): the game refills it each
+    /// The custom sky layers the next frame draws (`CustomSky::draws`): the game refills it each
    /// frame, empty when the world's sky has none.
    pub fn custom_sky_draws(&mut self) -> &mut Vec<crate::custom_sky::Draw> {
        &mut self.custom_sky_draws
    }
    /// The resource packs' `core/rendertype_lines` (`HudAtlas::lines_shader`) for the block
    /// outline, or the built-in one.
-    pub fn set_lines_shader(&mut self, program: Option<&crate::core_shader::CoreProgram>) {
+    pub fn set_lines_shader(&mut self, program: Option<&horizon_shaders::CoreProgram>) {
        let format = self.output.frame.format;
        self.core_lines =
            program.and_then(|program| core_lines::CoreLines::new(&self.device, format, program));
@@ -5537,8 +5527,8 @@ impl Renderer {
    /// `stars_shader`), or the built-in sky and stars.
    pub fn set_sky_shaders(
        &mut self,
-        disc: Option<&crate::core_shader::CoreProgram>,
-        stars: Option<&crate::core_shader::CoreProgram>,
+        disc: Option<&horizon_shaders::CoreProgram>,
+        stars: Option<&horizon_shaders::CoreProgram>,
    ) {
        self.core_sky = core_sky::CoreSky::new(&self.device, self.output.frame.format, disc, stars);
    }
@@ -5641,7 +5631,6 @@ impl Renderer {
        }
        self.surface_unconfigured = configured.is_err();
        self.surface = Some(Arc::new(surface));
-        self.surface_recreated();
        Ok(())
    }
    /// The world's depth, which occlusion culling's test and post effects may read.
@@ -7094,6 +7083,18 @@ impl Renderer {
            horizon_hdr::set_metadata(&self.device, surface, hdr.declared_peak(), hdr.black);
        }
    }
+    /// The swapchain's configuration: `config` (what every pipeline draws in), or
+    /// HDR10 or scRGB while HDR output is on.
+    fn surface_config(&self) -> wgpu::SurfaceConfiguration {
+        let mut config = self.config.clone();
+        if let Some(hdr) = &self.hdr {
+            config.format = hdr.output.format();
+            config.view_formats = vec![hdr.output.format()];
+            config.color_space = hdr.output.color_space();
+            config.usage = wgpu::TextureUsages::RENDER_ATTACHMENT;
+        }
+        config
+    }
    /// This renderer's output as applied, with what its destination offers and reports.
    pub fn output(&self) -> &output::EffectiveOutput {
        &self.output
@@ -7148,11 +7149,106 @@ impl Renderer {
        output::resolve_frame(
            settings,
            request,
-            self.caps_for(settings),
-            output_apply::graced(self.auto_off_since, self.reading, &self.output),
+            self.output_caps,
+            self.reading,
            self.config.format,
        )
    }
+    /// Follows the selected mode even when Auto currently wants SDR. Off never asks
+    /// the system about the display; selecting On or Auto starts a fresh watch.
+    fn watch_hdr(&mut self, mode: crate::graphics::HdrMode) {
+        if mode == crate::graphics::HdrMode::Off {
+            self.display = None;
+            self.display_fresh = false;
+            self.reading.stop_watching();
+        } else if self.display.is_none() {
+            let (watch, now) =
+                DisplayWatch::new(&self.window, self.surface.as_deref(), &self.adapter);
+            self.display = Some(watch);
+            self.refresh_hdr_offer();
+            self.reading = now;
+            self.display_fresh = true;
+        }
+    }
+    /// What the window's surface offers now: Vulkan's offered formats can change with desktop
+    /// HDR or the window's output.
+    fn refresh_hdr_offer(&mut self) {
+        if let Some(surface) = &self.surface {
+            self.output_caps.hdr = hdr::output(&surface.get_capabilities(&self.adapter));
+        }
+    }
+    /// HDR output (Horizon setting) as `settings` ask for it on this renderer's frame
+    /// (`output::resolve_output`): HDR10 or scRGB at paper white, the world's highlights
+    /// expanded up to the peak. Off where the surface can't present it. Offscreen
+    /// (`hdr::offscreen_output`) the frame is drawn the same and its HDR screenshot taken,
+    /// but nothing is presented, and Auto takes its defaults: no display reports.
+    pub fn update_output(
+        &mut self,
+        settings: &crate::graphics::Graphics,
+        marker: &std::path::Path,
+    ) {
+        self.watch_hdr(settings.hdr);
+        let next = output::resolve_output(
+            settings,
+            self.output_caps,
+            self.reading,
+            self.output.frame,
+            self.surface.is_some() || self.offscreen.is_some(),
+        );
+        let [paper_white, peak, black] = next.nits;
+        if next.encoding.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 next.encoding.is_some() {
+                if self.surface.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 frame = self.output.frame;
+            self.hdr = next.encoding.map(|output| {
+                hdr::Hdr::new(
+                    &self.device,
+                    &self.queue,
+                    frame.format,
+                    output,
+                    frame.hud_layer,
+                )
+            });
+            if let Some(hdr) = &mut self.hdr {
+                hdr.look = self.hdr_lighting_setting;
+            }
+            self.configure_surface();
+            match next.encoding {
+                Some(output) => log::info!(
+                    "Horizon renderer: HDR on: {} ({:?}), {paper_white}/{peak} nits",
+                    output.name(),
+                    output.format()
+                ),
+                None => log::info!("Horizon renderer: HDR off"),
+            }
+            self.measure_emission();
+        }
+        if let Some(hdr) = &mut self.hdr {
+            hdr.ui = next.ui_brightness;
+        }
+        if let Some(hdr) = &mut self.hdr
+            && (hdr.paper_white, hdr.peak, hdr.black) != (paper_white, peak, black)
+        {
+            hdr.paper_white = paper_white;
+            hdr.peak = peak;
+            hdr.black = black;
+            self.send_hdr_metadata();
+        }
+        // An output of another encoding than the one presented doesn't replace it yet, only
+        // Off does: the snapshot says what is presented.
+        self.output = output::EffectiveOutput {
+            encoding: self.hdr.as_ref().map(|hdr| hdr.output),
+            ..next
+        };
+    }
    /// Measures which pixels of each block sprite may shine (`hdr_stats`), at the current
    /// masks. Only with HDR output on: without it the frame's alpha is never read.
    pub fn measure_emission(&mut self) {
@@ -7162,6 +7258,24 @@ impl Renderer {
                .measure(&self.device, &self.queue, &views, hdr.masks);
        }
    }
+    /// Whether what the system reports for the display changed (another output, the
+    /// player recalibrating the desktop): the settings' Auto values follow it then, so
+    /// apply them again.
+    pub fn display_changed(&mut self) -> bool {
+        flush_display_log();
+        if std::mem::take(&mut self.display_fresh) {
+            return true;
+        }
+        let Some(watch) = self.display.as_mut() else {
+            return false;
+        };
+        let Some(now) = watch.changed(self.reading, self.surface.as_deref(), &self.adapter) else {
+            return false;
+        };
+        self.refresh_hdr_offer();
+        self.reading = now;
+        true
+    }
    /// The share of real frames frame generation shows a made frame before (1 while it
    /// keeps up), `None` while it isn't running.
    /// The posed models' store size (`SkinFrame::base`), with entity skinning.
@@ -7547,7 +7661,7 @@ impl Renderer {
    ) -> std::result::Result<Vec<String>, String> {
        let linear = pack
            .as_ref()
-            .is_some_and(|p| p.0.manifest.api == horizon_shader_api::Api::V0_2);
+            .is_some_and(|p| p.0.manifest.api == horizon_render_pipeline::Api::V0_2);
        if (linear || self.output.frame.format == LINEAR_FRAME)
            && linear != (self.output.frame.format == LINEAR_FRAME)
            && !std::mem::replace(&mut self.frame_kept_logged, true)
@@ -7600,7 +7714,7 @@ impl Renderer {
                inputs.declarations.push_str(
                    "layout(set = 5, binding = 0) readonly buffer HzIndices { uint hz_indices[]; };\n",
                );
-                horizon_shaders::GeometryInputs {
+                horizon_render_pipeline::GeometryInputs {
                    inputs,
                    pull: pack_atlas::PULL.to_owned(),
                    index: "hz_indices[@]".to_owned(),
@@ -7623,7 +7737,7 @@ impl Renderer {
        }
    }

-    fn pack_terrain_inputs(&mut self) -> Option<horizon_shaders::GbuffersInputs> {
+    fn pack_terrain_inputs(&mut self) -> Option<horizon_render_pipeline::GbuffersInputs> {
        // Flat draws whenever the device has them (`render` keeps them on with a pack).
        let flat = self.flat.is_some() && self.flat_on;
        // Flat draws read each sprite's place from a table: the atlas is stitched as the game's.
@@ -8349,12 +8463,8 @@ impl Renderer {
            t.begin(&self.device, &self.queue);
        }
        if self.animated_textures {
-            self.hud.animate(
-                &mut self.uploads,
-                &mut encoder,
-                frame.ticks,
-                &self.animations,
-            );
+            self.hud
+                .animate_sprites(&mut self.uploads, &mut encoder, frame.ticks);
        }
        self.update_lightmap(
            &mut encoder,
@@ -9292,11 +9402,13 @@ impl Renderer {
        }
        // Near water and distant water share one back-to-front draw order.
        if self.translucent_draws.len() > section_translucent {
-            // Distant water goes after the near chunks', and replaced tiles' after all: each is a
-            // hair behind the one before, so depth leaves it only where that one has none. Back to
-            // front together, a far tile's water under a near chunk's (one fading in, or brought
-            // into view by a longer render distance) blended twice and looked opaque. The cost: far
-            // water just behind near water shows no surface of its own there.
+            // Distant water goes after the near chunks', and replaced tiles'
+            // after all: each is a hair behind the one before, so depth leaves
+            // it only where that one has none. Back to front together, a far
+            // tile's water under a near chunk's (one fading in, or brought
+            // into view by a longer render distance) blended twice and looked
+            // opaque. The cost: far water just behind near water shows no
+            // surface of its own there.
            let tier = |instance: usize| match instance.checked_sub(visible.len()) {
                None => 0,
                Some(tile) if visible_lods[tile].old => 2,
@@ -10298,7 +10410,7 @@ impl Renderer {
                self.own_timing.as_mut(),
            );
            pass.set_bind_group(0, &self.group, &[]);
-            pass.set_bind_group(horizon_shader_api::stages::GROUP, &shadow.group, &[]);
+            pass.set_bind_group(horizon_render_pipeline::stages::GROUP, &shadow.group, &[]);
            if flat_frame
                && let Some(flat) = &self.flat
                && let Some(pipeline) = &shadow.flat
@@ -10331,7 +10443,7 @@ impl Renderer {
                self.own_timing.as_mut(),
            );
            pass.set_bind_group(0, &self.group, &[]);
-            pass.set_bind_group(horizon_shader_api::stages::GROUP, &shadow.group, &[]);
+            pass.set_bind_group(horizon_render_pipeline::stages::GROUP, &shadow.group, &[]);
            if flat_frame
                && let Some(flat) = &self.flat
                && let Some(pipeline) = &shadow.flat_translucent
@@ -10363,7 +10475,7 @@ impl Renderer {
                    .begin_entities(&mut encoder, "Native shader pack entity shadow");
                pass.set_pipeline(&shadow.entity);
                pass.set_bind_group(0, &self.entity_group, &[]);
-                pass.set_bind_group(horizon_shader_api::stages::GROUP, &shadow.group, &[]);
+                pass.set_bind_group(horizon_render_pipeline::stages::GROUP, &shadow.group, &[]);
                pass.set_vertex_buffer(0, self.entity_buffer.slice(..));
                pass.set_index_buffer(self.indices.slice(..), wgpu::IndexFormat::Uint32);
                pass.draw_indexed(0..entity_quads * 6, 0, 0..1);
@@ -10584,7 +10696,7 @@ impl Renderer {
        let gpu_occluding = gpu_frame && self.gpu_culling.as_ref().is_some_and(|g| g.occluding());
        let pack_frame = |pass: &mut wgpu::RenderPass<'_>| {
            if let Some((_, group)) = material {
-                pass.set_bind_group(horizon_shader_api::stages::GROUP, group, &[]);
+                pass.set_bind_group(horizon_render_pipeline::stages::GROUP, group, &[]);
            }
        };
        // A pack's solid terrain that calls `set_surface` also writes the surface target, in
@@ -11972,7 +12084,7 @@ impl Renderer {
            && self
                .native
                .as_ref()
-                .is_none_or(|n| n.frame.api == horizon_shader_api::Api::V0_1);
+                .is_none_or(|n| n.frame.api == horizon_render_pipeline::Api::V0_1);
        match (&self.hdr, &surface_frame) {
            (Some(hdr), Some(f)) => hdr.present(
                &self.queue,
@@ -15287,10 +15399,6 @@ struct DisplayWatch {
 }

 impl DisplayReading {
-    /// What wgpu reads from the OS for `surface`'s display; nothing without one.
-    fn read(surface: Option<&wgpu::Surface>, adapter: &wgpu::Adapter) -> Self {
-        surface.map_or_else(Self::default, |s| Self::os(&s.display_hdr_info(adapter)))
-    }
    fn os(info: &wgpu::DisplayHdrInfo) -> Self {
        #[cfg(target_os = "macos")]
        let hdr = macos_hdr(info);
@@ -15331,7 +15439,9 @@ impl DisplayWatch {
            return (watch, wayland_reading(now));
        }
        let _ = window;
-        let now = DisplayReading::read(surface, adapter);
+        let now = surface.map_or_else(DisplayReading::default, |surface| {
+            DisplayReading::os(&surface.display_hdr_info(adapter))
+        });
        log_os_reported(now.luminance);
        let watch = Self {
            #[cfg(target_os = "linux")]
@@ -15340,28 +15450,30 @@ impl DisplayWatch {
        };
        (watch, now)
    }
-    /// What the system reports at each poll that is due at `time` (`read`; on Wayland, at each
-    /// event), whether or not it is `last` again: the surface's capabilities are read with it.
-    fn poll(
+    /// What the system reports, if that changed from `last`.
+    fn changed(
        &mut self,
        last: DisplayReading,
-        time: std::time::Instant,
-        read: impl FnOnce() -> DisplayReading,
+        surface: Option<&wgpu::Surface>,
+        adapter: &wgpu::Adapter,
    ) -> Option<DisplayReading> {
        #[cfg(target_os = "linux")]
        if let Some(wayland) = &mut self.wayland {
            return wayland.changed().map(wayland_reading);
        }
        let next = self.polled.as_mut()?;
+        let time = std::time::Instant::now();
        if time < *next {
            return None;
        }
        *next = time + DISPLAY_POLL;
-        let now = read();
-        if now != last {
+        let now = surface.map_or_else(DisplayReading::default, |surface| {
+            DisplayReading::os(&surface.display_hdr_info(adapter))
+        });
+        (now != last).then(|| {
            log_os_reported(now.luminance);
-        }
-        Some(now)
+            now
+        })
    }
 }

@@ -15718,11 +15830,11 @@ mod shadow_caster_tests {
    #[test]
    fn the_shadow_pass_draws_terrain_outside_the_pack_s_planes() {
        let kept = |near: Option<f32>, far: Option<f32>, y: f64, min: [f32; 3], depth: bool| {
-            let shadow = horizon_shaders::Shadow {
+            let shadow = horizon_render_pipeline::Shadow {
                distance: 128.0,
                near,
                far,
-                ..horizon_shaders::Shadow::default()
+                ..horizon_render_pipeline::Shadow::default()
            };
            let camera = DVec3::new(13.5, y + 1.62, -13.5);
            let view = pack_post::ShadowView {
@@ -64,7 +64,7 @@ enum Writer {
    },
 }

-pub(crate) struct SpriteAnimator {
+pub(super) struct SpriteAnimator {
    sprites: Vec<Sprite>,
    groups: Vec<Group>,
    writer: Writer,
@@ -86,9 +86,6 @@ struct AnimationModes {
    day_time: i64,
    weather: f32,
    values: std::collections::HashMap<String, f64>,
-    /// The open screen (an identity the game picks) and the ticks it has been open.
-    screen: Option<u64>,
-    screen_time: i64,
 }

 impl AnimationModes {
@@ -119,15 +116,8 @@ impl super::Renderer {
        day_time: i64,
        [rain, thunder]: [f32; 2],
        frame: Option<&crate::environment::Frame>,
-        screen: Option<u64>,
    ) {
        let modes = &mut self.animations.modes;
-        // `screen_time`: a tick more while the same screen stays open, from 0 on a new one.
-        modes.screen_time = match (screen, modes.screen) {
-            (Some(open), Some(was)) if open == was => modes.screen_time + 1,
-            _ => 0,
-        };
-        modes.screen = screen;
        modes.day_time = day_time;
        modes.weather = rain + thunder;
        modes.values.clear();
@@ -143,16 +133,6 @@ impl super::Renderer {
 }

 impl SpriteAnimator {
-    /// What the modes read this frame, for the GUI atlas's sprites (their expressions aren't
-    /// compiled: those run on ticks).
-    pub(crate) fn mode_inputs(&self) -> horizon_assets::animation::ModeInputs<'static> {
-        horizon_assets::animation::ModeInputs {
-            day_time: self.modes.day_time,
-            screen_time: self.modes.screen_time,
-            weather: self.modes.weather,
-            expression: &|_| None,
-        }
-    }
    /// `textures` are the sprite arrays, `split` layers each, `size` pixels
    /// wide; `animations` hold their frames at that size. `compute`: whether
    /// the device says it runs compute shaders writing storage textures.
@@ -381,7 +361,6 @@ impl SpriteAnimator {
        let expression = |source: &str| values.get(source).copied();
        let inputs = horizon_assets::animation::ModeInputs {
            day_time: self.modes.day_time,
-            screen_time: self.modes.screen_time,
            weather: self.modes.weather,
            expression: &expression,
        };
@@ -2,8 +2,8 @@
 //! and `secondaryBlockOutline` under a high contrast one): an outline its fragment shader colours
 //! or animates. Without one the outline draws natively (`vs_line` in terrain.wgsl).

-use crate::core_shader::{CoreProgram, Glue};
 use glam::Mat4;
+use horizon_shaders::{CoreProgram, Glue};

 /// The outline's edges (`pack_lines::layout`: start, end, ARGB colour and width per instance) as
 /// vanilla's lines: four vertices an edge, the start twice and the end twice, the side
@@ -425,7 +425,7 @@ mod tests {
            eprintln!("no GPU: skipping");
            return;
        };
-        let program = crate::core_shader::translate_core(LINES_VSH, RGB_FSH, &[], &include, &GLUE)
+        let program = horizon_shaders::translate_core(LINES_VSH, RGB_FSH, &[], &include, &GLUE)
            .expect("the shaders translate");
        assert_pack_coloured(&draw_edge(&device, &queue, &program));
    }
@@ -441,7 +441,7 @@ mod tests {
            include(id)
                .map(|text| text.replace("vec3 ModelOffset;", "vec3 ModelOffset;\n    vec4 More;"))
        };
-        let program = crate::core_shader::translate_core(LINES_VSH, RGB_FSH, &[], &bigger, &GLUE)
+        let program = horizon_shaders::translate_core(LINES_VSH, RGB_FSH, &[], &bigger, &GLUE)
            .expect("the shaders translate");
        assert!(CoreLines::new(&device, wgpu::TextureFormat::Rgba8Unorm, &program).is_none());
    }
@@ -470,11 +470,11 @@ mod tests {
            let (namespace, path) = id.split_once(':')?;
            std::fs::read_to_string(root.join(format!("assets/{namespace}/{path}"))).ok()
        };
-        let program = crate::core_shader::translate_core(&vertex, RGB_FSH, &[], &include, &GLUE)
+        let program = horizon_shaders::translate_core(&vertex, RGB_FSH, &[], &include, &GLUE)
            .expect("vanilla's vertex shader translates");
        // A pack that replaces only the vertex shader runs vanilla's fragment shader.
        let fragment = include("minecraft:shaders/core/rendertype_lines.fsh").unwrap();
-        let vanilla = crate::core_shader::translate_core(&vertex, &fragment, &[], &include, &GLUE)
+        let vanilla = horizon_shaders::translate_core(&vertex, &fragment, &[], &include, &GLUE)
            .expect("vanilla's fragment shader translates");
        let Some((device, queue)) = device() else {
            eprintln!("no GPU: skipping the draw");
@@ -3,8 +3,8 @@
 //! to the horizon or tints the night sky expects. Without one the sky draws natively (`fs_sky` in
 //! terrain.wgsl, stars.rs).

-use crate::core_shader::{CoreProgram, Glue};
 use glam::Mat4;
+use horizon_shaders::{CoreProgram, Glue};
 use wgpu::util::DeviceExt;

 /// `DefaultVertexFormat.POSITION`: the disc's and the stars' vertices.
@@ -325,7 +325,7 @@ mod tests {
        let fragment = "#version 330\n#include <minecraft:dynamictransforms.glsl>\n\
            layout(location = 0) out vec4 fragColor;\n\
            void main() {\n    fragColor = ColorModulator;\n}\n";
-        let program = crate::core_shader::translate_core(&vertex, fragment, &[], &include, &GLUE)
+        let program = horizon_shaders::translate_core(&vertex, fragment, &[], &include, &GLUE)
            .expect("the sky shaders translate");
        let instance = crate::gfx::test_gpu::instance();
        let Some((device, queue)) =
@@ -1,11 +1,12 @@
-//! Custom sky layers (`crate::custom_sky`) on the GPU: one texture per layer, kept with the renderer (its pack),
+//! OptiFine custom sky layers on the GPU: one texture per layer, kept with the renderer (its pack),
 //! a static skybox mesh of the 3x2 grid's six faces, and one pipeline per blend mode. A frame
 //! uploads one small uniform per drawn layer ([`crate::custom_sky::Draw`]) and draws 36 vertices
 //! each, after the vanilla sky's disc and sunrise and before the sun, moon and stars.
 use glam::Mat4;
+use horizon_optifine::sky::{Blend, Face};
 use wgpu::util::DeviceExt;

-use crate::custom_sky::{Blend, Draw, SkyLayers};
+use crate::custom_sky::{CustomSky as Pack, Draw};

 /// The blend modes in the shader's `mode` order (custom_sky.wgsl).
 const MODES: [Blend; 9] = [
@@ -84,76 +85,6 @@ fn blend(mode: Blend) -> wgpu::BlendComponent {
    }
 }

-/// A face of the skybox, as the 3x2 grid of its texture holds them: `Bottom`, `Top`, `South` in
-/// the top row, `West`, `North`, `East` below.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-enum Face {
-    Bottom,
-    Top,
-    South,
-    West,
-    North,
-    East,
-}
-
-impl Face {
-    const ALL: [Self; 6] = [
-        Self::Bottom,
-        Self::Top,
-        Self::South,
-        Self::West,
-        Self::North,
-        Self::East,
-    ];
-
-    /// The face's cell of the texture, `[u0, v0, u1, v1]` in 0..1.
-    fn cell(self) -> [f32; 4] {
-        let (col, row) = match self {
-            Self::Bottom => (0, 0),
-            Self::Top => (1, 0),
-            Self::South => (2, 0),
-            Self::West => (0, 1),
-            Self::North => (1, 1),
-            Self::East => (2, 1),
-        };
-        let (u, v) = (col as f32 / 3.0, row as f32 / 2.0);
-        [u, v, u + 1.0 / 3.0, v + 0.5]
-    }
-
-    /// The face's corners (on the unit cube around the camera; x east, y up, z south) in the
-    /// order of its cell's `(u0, v0)`, `(u1, v0)`, `(u1, v1)`, `(u0, v1)`. The side faces are
-    /// seen from inside with up at the top of their cell; the top face has north at the bottom of
-    /// its cell, the bottom face north at the top (the template's `N` marks).
-    fn corners(self) -> [[f32; 3]; 4] {
-        match self {
-            // Seen looking north: west on the left.
-            Self::North => [
-                [-1., 1., -1.],
-                [1., 1., -1.],
-                [1., -1., -1.],
-                [-1., -1., -1.],
-            ],
-            Self::South => [[1., 1., 1.], [-1., 1., 1.], [-1., -1., 1.], [1., -1., 1.]],
-            Self::East => [[1., 1., -1.], [1., 1., 1.], [1., -1., 1.], [1., -1., -1.]],
-            Self::West => [
-                [-1., 1., 1.],
-                [-1., 1., -1.],
-                [-1., -1., -1.],
-                [-1., -1., 1.],
-            ],
-            // Looking up with north toward the cell's bottom edge: east on the right.
-            Self::Top => [[-1., 1., 1.], [1., 1., 1.], [1., 1., -1.], [-1., 1., -1.]],
-            // Looking down with north toward the cell's top edge: east on the right.
-            Self::Bottom => [
-                [-1., -1., -1.],
-                [1., -1., -1.],
-                [1., -1., 1.],
-                [-1., -1., 1.],
-            ],
-        }
-    }
-}
-
 /// The skybox's 36 vertices: two triangles per face, each corner with its cell's UV.
 fn mesh() -> Vec<Vertex> {
    let mut out = Vec::with_capacity(36);
@@ -325,15 +256,10 @@ impl CustomSky {
    }

    /// The pack's layer textures, replacing any before.
-    pub(super) fn set_pack(
-        &mut self,
-        device: &wgpu::Device,
-        queue: &wgpu::Queue,
-        pack: &dyn SkyLayers,
-    ) {
+    pub(super) fn set_pack(&mut self, device: &wgpu::Device, queue: &wgpu::Queue, pack: &Pack) {
        let limit = device.limits().max_texture_dimension_2d;
        self.groups = pack
-            .images()
+            .images
            .iter()
            .map(|image| {
                // Too large for this GPU: a 1x1 transparent texel, so the layer draws nothing.
@@ -487,38 +413,6 @@ impl CustomSky {
 mod tests {
    use super::*;

-    #[test]
-    fn the_grid_holds_each_face_once_and_faces_point_out() {
-        let mut cells: Vec<_> = Face::ALL
-            .iter()
-            .map(|f| f.cell().map(|x| (x * 6.0) as i32))
-            .collect();
-        cells.dedup();
-        assert_eq!(cells.len(), 6);
-        assert_eq!(Face::East.cell(), [2.0 / 3.0, 0.5, 1.0, 1.0]);
-        for face in Face::ALL {
-            let c = face.corners();
-            let sub = |a: [f32; 3], b: [f32; 3]| [a[0] - b[0], a[1] - b[1], a[2] - b[2]];
-            let (a, b) = (sub(c[1], c[0]), sub(c[3], c[0]));
-            let n = [
-                a[1] * b[2] - a[2] * b[1],
-                a[2] * b[0] - a[0] * b[2],
-                a[0] * b[1] - a[1] * b[0],
-            ];
-            let centre: [f32; 3] =
-                std::array::from_fn(|i| c.iter().map(|p| p[i]).sum::<f32>() / 4.0);
-            // Seen from inside, u runs right and v down, so u x v points away from the camera.
-            let dot: f32 = (0..3).map(|i| n[i] * centre[i]).sum();
-            assert!(dot > 0.0, "{face:?} is mirrored");
-        }
-        // The top cell's bottom edge (v1) is north: its corners 2 and 3 have z = -1.
-        assert_eq!(Face::Top.corners()[2][2], -1.0);
-        assert_eq!(Face::Top.corners()[3][2], -1.0);
-        // The bottom cell's top edge (v0) is north.
-        assert_eq!(Face::Bottom.corners()[0][2], -1.0);
-        assert_eq!(Face::Bottom.corners()[1][2], -1.0);
-    }
-
    /// What a blend leaves a sky texel of `dst` with when the shader outputs `src`
    /// (custom_sky.wgsl) for a layer texel `t` at brightness `b`, per channel.
    fn mix(mode: Blend, dst: f32, t: f32, a: f32, b: f32) -> f32 {
@@ -6,7 +6,7 @@ struct Layer {
    // Projection * view (camera-relative) * the layer's rotation.
    clip_from_sky: mat4x4<f32>,
    brightness: f32,
-    // crate::custom_sky::Blend, in gfx/custom_sky.rs's MODES order.
+    // horizon_optifine::sky::Blend, in gfx/custom_sky.rs's MODES order.
    mode: u32,
    pad: vec2<u32>,
    hdr_settings: vec4<f32>,
@@ -1,25 +1,3 @@
-// This file is part of the FidelityFX SDK.
-//
-// Copyright (C) 2024 Advanced Micro Devices, Inc.
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files(the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and /or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions :
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
 //! FSR 3.1's frame interpolation (AMD FidelityFX SDK 1.1.4, `ffx_frameinterpolation*`,
 //! MIT), ported to WGSL (`interpolation.wgsl`): the frame halfway between the previous
 //! real frame and this one, from the camera's motion vectors, the optical flow
@@ -185,7 +185,7 @@ pub struct Hdr {
    /// The display's black level, in nits: shadows are lifted onto it (`hdr.wgsl`).
    pub black: f32,
    pub tiers: [Tier; 4],
-    /// The HUD and menus' brightness, as a share of paper white: above 1 brighter than it.
+    /// The HUD and menus' brightness, as a share of paper white (0.25..=1).
    pub ui: f32,
    /// Which pixels of a light source shine (`Masks`).
    pub masks: Masks,
@@ -419,26 +419,6 @@ impl Hdr {
        }
    }

-    /// The same HDR output presenting `output` instead (`output_apply`): the same frame and
-    /// HUD layer, and the player's tuning as it is (HDR Lighting, the world's lighting, the UI
-    /// brightness, the masks and tiers, the debug view, calibration and the luminance). Its
-    /// targets are made again on the next frame.
-    pub fn retargeted(&self, device: &wgpu::Device, queue: &wgpu::Queue, output: Output) -> Self {
-        Self {
-            debug: self.debug,
-            paper_white: self.paper_white,
-            peak: self.peak,
-            black: self.black,
-            tiers: self.tiers,
-            ui: self.ui,
-            masks: self.masks,
-            lighting: self.lighting,
-            look: self.look,
-            calibration: self.calibration,
-            ..Self::new(device, queue, self.format, output, self.layered.is_some())
-        }
-    }
-
    /// The frame every pass draws into this frame, sized like the window.
    pub fn frame(&mut self, device: &wgpu::Device, size: [u32; 2]) -> wgpu::Texture {
        if self.targets.as_ref().is_none_or(|t| t.size != size) {
@@ -956,7 +936,7 @@ impl Hdr {
            f32::from(u8::from(pq)),
        ]);
        params[5] = self.black.clamp(0.0, paper);
-        params[6] = self.ui;
+        params[6] = self.ui.clamp(0.25, 1.0);
        params[7] = if self.lighting {
            scene_gain(self.peak, self.paper_white)
        } else {
@@ -1561,93 +1541,6 @@ struct ReferenceParams { peak: f32, scene: f32, world: f32, debug: f32, share: v
        assert!(r == 1.0 && near(g, 0.5) && near(b, 0.2), "{r} {g} {b}");
    }

-    /// HDR output switched from HDR10 to scRGB and back (`output_apply`): the player's tuning
-    /// stays, each swapchain gets the same light in its own encoding, and the HDR10 capture
-    /// and the HDR10 picture after the switch back are the ones before it.
-    #[test]
-    fn a_switched_encoding_keeps_the_tuning_and_shows_the_same_light() {
-        let Some((device, queue)) = gpu() else {
-            eprintln!("HDR encoding switch GPU skipped: no adapter");
-            return;
-        };
-        let mut hdr = Hdr::with_debug(&device, &queue, F::Rgba16Float, Output::Pq, true, None);
-        (hdr.paper_white, hdr.peak, hdr.black) = (250.0, 800.0, 0.0);
-        (hdr.ui, hdr.look, hdr.lighting) = (0.5, false, false);
-        hdr.masks.parts = 0.4;
-        hdr.tiers[1].share = 0.7;
-        hdr.debug = true;
-        hdr.calibration = Some(super::Calibration {
-            step: 2,
-            nits: 700.0,
-            band: 0.6,
-        });
-        let tuning = |h: &Hdr| {
-            (
-                [h.paper_white, h.peak, h.black, h.ui],
-                (h.look, h.lighting, h.debug, h.layered.is_some(), h.format),
-                (h.masks, h.tiers, h.calibration),
-            )
-        };
-        let switched = hdr.retargeted(&device, &queue, Output::ScRgb);
-        assert_eq!(switched.output, Output::ScRgb);
-        assert_eq!(tuning(&switched), tuning(&hdr));
-        hdr.calibration = None;
-        hdr.debug = false;
-        // The swapchain's first texel (`capture`: the HDR10 screenshot's) for light 2 times
-        // paper white, grey, as the layered frame stores it.
-        let shot = |hdr: &mut Hdr, capture: bool| {
-            let frame = hdr.frame(&device, [1, 1]);
-            let mut encoder = device.create_command_encoder(&Default::default());
-            let g = 2f64.powf(1.0 / 2.2);
-            fill(&mut encoder, &frame, [g, g, g, 1.0]);
-            hdr.begin(&queue, true);
-            hdr.keep_world(&mut encoder, None);
-            super::super::hud_coverage::clear(&mut encoder, &hdr.coverage_view().unwrap());
-            let target = if capture {
-                hdr.capture(&device, &queue, &mut encoder, true).unwrap()
-            } else {
-                device.create_texture(&wgpu::TextureDescriptor {
-                    label: None,
-                    size: frame.size(),
-                    mip_level_count: 1,
-                    sample_count: 1,
-                    dimension: wgpu::TextureDimension::D2,
-                    format: hdr.output.format(),
-                    usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_SRC,
-                    view_formats: &[],
-                })
-            };
-            if !capture {
-                hdr.present(&queue, &mut encoder, &target, true, None);
-            }
-            texel(&device, &queue, encoder, &target)
-        };
-        // BT.2100's PQ EOTF: a 10-bit code's nits.
-        let pq_nits = |code: f32| {
-            let (m1, m2) = (2610.0 / 16384.0, 2523.0 / 4096.0 * 128.0);
-            let (c1, c2, c3) = (3424.0 / 4096.0, 2413.0 / 128.0, 2392.0 / 128.0);
-            let p = (code / 1023.0f32).powf(1.0 / m2);
-            ((p - c1).max(0.0) / (c2 - c3 * p)).powf(1.0 / m1) * 10000.0
-        };
-        let pq = shot(&mut hdr, false);
-        let pq_capture = shot(&mut hdr, true);
-        let mut scrgb = hdr.retargeted(&device, &queue, Output::ScRgb);
-        let linear = shot(&mut scrgb, false);
-        assert_eq!(shot(&mut scrgb, true), pq_capture);
-        // Two times paper white in both: 500 nits, as HDR10's code and as scRGB's 80-nit units.
-        let near = |got: f32| (got - 500.0).abs() <= 0.015 * 500.0;
-        assert!(
-            near(pq_nits(pq[0])) && pq[..3].iter().all(|&c| c == pq[0]),
-            "{pq:?}"
-        );
-        assert!(near(linear[0] * 80.0), "{linear:?}");
-        let mut back = scrgb.retargeted(&device, &queue, Output::Pq);
-        assert_eq!(
-            (shot(&mut back, false), shot(&mut back, true)),
-            (pq, pq_capture)
-        );
-    }
-
    /// ITU-R BT.2390's black level lift on grey light, in HDR10 and in scRGB, against values
    /// worked out apart from the shader, in f64 from SMPTE ST 2084: E3 = E2 + b (1 - E2)^4 on
    /// the PQ signal, for a source from 0 to the peak and b the black level's share of it.
@@ -1906,11 +1799,9 @@ struct ReferenceParams { peak: f32, scene: f32, world: f32, debug: f32, share: v
            // Covered: the HUD as drawn, at UI Brightness.
            (2.0, 0.3, 1.0, 1.0, 0.3),
            (2.0, 0.3, 1.0, 0.5, 0.3 * 0.5f32.powf(1.0 / 2.2)),
-            // UI Brightness above paper white: brighter than drawn.
-            (2.0, 0.3, 1.0, 2.0, 0.3 * 2f32.powf(1.0 / 2.2)),
            // Added over the world (the text highlight), which it doesn't hide.
            (0.6, 0.8, 0.0, 1.0, 0.8),
-            // At or below white, at paper white: the HUD's picture as drawn.
+            // At or below white, at 100%: the HUD's picture as drawn.
            (0.7, 0.45, 0.5, 1.0, 0.45),
        ] {
            hdr.ui = ui;
@@ -1930,50 +1821,6 @@ struct ReferenceParams { peak: f32, scene: f32, world: f32, debug: f32, share: v
        }
    }

-    /// On the frame without the HUD's layer, the HUD at UI Brightness reaches its nits, and
-    /// above the peak stops there, as on the layered frame.
-    #[test]
-    fn the_hud_at_ui_brightness_stops_at_the_peak() {
-        let Some((device, queue)) = gpu() else {
-            return;
-        };
-        let mut hdr = Hdr::with_debug(&device, &queue, F::Rgba8Unorm, Output::ScRgb, false, None);
-        (hdr.paper_white, hdr.peak) = (200.0, 300.0);
-        let target = device.create_texture(&wgpu::TextureDescriptor {
-            label: None,
-            size: wgpu::Extent3d {
-                width: 1,
-                height: 1,
-                depth_or_array_layers: 1,
-            },
-            mip_level_count: 1,
-            sample_count: 1,
-            dimension: wgpu::TextureDimension::D2,
-            format: Output::ScRgb.format(),
-            usage: wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::COPY_SRC,
-            view_formats: &[],
-        });
-        // UI Brightness (a share of paper white) and the white HUD's nits.
-        for (ui, want) in [(0.5, 100.0), (1.25, 250.0), (2.0, 300.0)] {
-            hdr.ui = ui;
-            let frame = hdr.frame(&device, [1, 1]);
-            let mut encoder = device.create_command_encoder(&Default::default());
-            fill(&mut encoder, &frame, [0.2, 0.2, 0.2, 1.0]);
-            hdr.keep_world(&mut encoder, None);
-            // Opaque white HUD over the world: alpha 1 is full coverage.
-            fill(&mut encoder, &frame, [1.0; 4]);
-            hdr.begin(&queue, true);
-            hdr.present(&queue, &mut encoder, &target, true, None);
-            let got = texel(&device, &queue, encoder, &target);
-            for c in &got[..3] {
-                assert!(
-                    (c * 80.0 - want).abs() < 0.5,
-                    "UI {ui}: {got:?}, not {want} nits"
-                );
-            }
-        }
-    }
-
    #[test]
    fn the_menu_blur_keeps_the_light_it_blurs() {
        let Some((device, queue)) = gpu() else {
@@ -1,65 +0,0 @@
-//! A window's HDR output start and what a failed one leaves (`graphics::HDR_MARKER`). Turning
-//! HDR output on writes a marker naming the window's graphics driver (`output::window_driver`);
-//! the first frame presented, turning HDR output off and a clean exit remove it. A start that
-//! finds it holds HDR output back on that driver (`output::held`) until a mode is chosen on the
-//! HDR page or the driver changes. Offscreen renderers have no driver: they never write the
-//! marker or hold HDR output back.
-use super::{Renderer, output};
-
-impl Renderer {
-    /// What this renderer's destination offers for `settings`: HDR output held back on a window
-    /// whose graphics driver a start failed on (`output::held`).
-    pub(super) fn caps_for(
-        &self,
-        settings: &crate::graphics::Graphics,
-    ) -> output::OutputCapabilities {
-        output::OutputCapabilities {
-            held: output::held(settings, self.hdr_driver.as_deref()),
-            ..self.output_caps
-        }
-    }
-
-    /// Takes the hold `settings` put on this window's driver into the capabilities, and says it
-    /// once per start.
-    pub(super) fn hold_hdr_back(&mut self, settings: &crate::graphics::Graphics) {
-        self.output_caps = self.caps_for(settings);
-        if self.output_caps.held
-            && let Some(driver) = &self.hdr_driver
-        {
-            static LOGGED: std::sync::Once = std::sync::Once::new();
-            LOGGED.call_once(|| {
-                log::warn!(
-                    "Horizon renderer: HDR output is held back: the last start with this graphics driver ({driver}) ended before HDR output showed a frame. Choose an HDR mode on the HDR page to try again (or remove hdrFailedStart from {})",
-                    crate::graphics::FILE
-                )
-            });
-        }
-    }
-
-    /// Writes the marker at `marker` as a window's HDR output turns on (`on`), and removes this
-    /// renderer's marker as it turns off.
-    pub(super) fn mark_hdr_start(&mut self, on: bool, marker: &std::path::Path) {
-        if !on {
-            self.drop_hdr_marker();
-        } else if self.surface.is_some()
-            && let Some(driver) = &self.hdr_driver
-        {
-            let _ = std::fs::write(marker, crate::graphics::hdr_marker_text(driver));
-            self.hdr_marker = Some(marker.to_owned());
-        }
-    }
-
-    /// The graphics driver this window's HDR output starts on (`output::window_driver`);
-    /// `None` offscreen.
-    pub fn hdr_driver(&self) -> Option<&str> {
-        self.hdr_driver.as_deref()
-    }
-
-    /// Removes this renderer's marker of an HDR output that hasn't presented a frame yet, for a
-    /// clean exit: only a crash may leave it.
-    pub fn drop_hdr_marker(&mut self) {
-        if let Some(marker) = self.hdr_marker.take() {
-            let _ = std::fs::remove_file(marker);
-        }
-    }
-}
@@ -8,7 +8,8 @@
 //! colour. They read the terrain's group 0, the flat draws' group 1 where those run, and the
 //! pack's frame at group 3.

-use horizon_shader_api::{check::CheckedStage, stages::GROUP};
+use horizon_render_pipeline::stages::GROUP;
+use horizon_shader_api::check::CheckedStage;

 use super::native_post::{NativeFrame, present_constants};
 use super::wgsl_prefix::{TERRAIN, prefixed, section};
@@ -369,7 +370,7 @@ fn shader_source(
    tags: &[(u32, u32)],
    materials: &[(u32, u32)],
    (vertex, displaced): (bool, bool),
-    api: horizon_shader_api::Api,
+    api: horizon_render_pipeline::Api,
 ) -> String {
    format!(
        "{source}\n// Horizon's terrain (terrain.wgsl)\n{}{}{}{}{}{ENTRIES}{}{}",
@@ -398,7 +399,7 @@ fn module(
    materials: &[(u32, u32)],
    vertex: bool,
    displaced: bool,
-    api: horizon_shader_api::Api,
+    api: horizon_render_pipeline::Api,
 ) -> Result<naga::Module, String> {
    let text = shader_source(&stage.source, tags, materials, (vertex, displaced), api);
    naga::front::wgsl::parse_str(&text)
@@ -417,7 +418,7 @@ impl NativeMaterial {
        vertex: bool,
        displaced: Option<&DisplacedShape<'_>>,
    ) -> Result<Self, String> {
-        let writes_surface = horizon_shader_api::stages::calls_set_surface(&stage.source);
+        let writes_surface = horizon_render_pipeline::stages::calls_set_surface(&stage.source);
        let module = module(
            stage,
            shape.sprite_tags,
@@ -586,7 +587,7 @@ impl NativeMaterial {
 }

 #[cfg(test)]
-pub(super) fn coverage_test_shader(api: horizon_shader_api::Api) -> String {
+pub(super) fn coverage_test_shader(api: horizon_render_pipeline::Api) -> String {
    use horizon_shader_api::{MANIFEST, Pack, StageKind, check};
    let manifest = format!(
        "schema = 1\nid = \"coverage\"\nname = \"Coverage\"\nversion = \"1\"\napi = \"{api}\"\n[material]\nfile = \"material.wgsl\"\n[displacement]\n"
@@ -829,7 +830,7 @@ mod tests {
                .into();
            let report = check(&Pack::from_files(files).unwrap()).unwrap();
            let source = report.stages[0].source.clone()
-                + horizon_shader_api::stages::PBR_STUB
+                + horizon_render_pipeline::stages::PBR_STUB
                + super::super::native_post::line_helpers(api)
                + entry;
            let module = device.create_shader_module(wgpu::ShaderModuleDescriptor {
@@ -1,7 +1,8 @@
 //! One of Horizon's own shader packs while it runs (docs/shaders.md): the frame its stages
 //! read, its sky, material and post stages, and the timer of their passes.

-use horizon_shader_api::{Report, StageKind};
+use horizon_render_pipeline::StageKind;
+use horizon_shader_api::Report;

 use super::displace::Displacement;
 use super::native_material::{DisplacedShape, NativeMaterial, TerrainShape};
@@ -253,7 +254,7 @@ impl NativePack {
            .transpose()?;
        // A 0.2 pack always has one: its decode and tonemap run without a chain too.
        let tonemap = others.iter().find(|s| s.kind == StageKind::Tonemap);
-        let post = (!post.is_empty() || api == horizon_shader_api::Api::V0_2)
+        let post = (!post.is_empty() || api == horizon_render_pipeline::Api::V0_2)
            .then(|| {
                let manifest = &report.manifest;
                NativePost::new(device, post, manifest, constants, format, &frame, tonemap)
@@ -7,9 +7,9 @@
 //! (`NativeFrame`).

 use glam::{Mat4, Vec3};
-use horizon_shader_api::{
-    Api, Frame as FrameInputs, StageKind, check::CheckedStage, stages::GROUP,
-};
+use horizon_render_pipeline::stages::{GROUP, POST_TARGET_BINDING};
+use horizon_render_pipeline::{Api, Frame as FrameInputs, StageKind};
+use horizon_shader_api::check::CheckedStage;

 use super::Frame;

@@ -338,7 +338,7 @@ pub struct NativeFrame {
    reflection_sampler: wgpu::Sampler,
    /// The shadow map the stages read, and the camera that draws it when the pack asks for one.
    pub shadow_map: super::native_shadow::ShadowMap,
-    shadow_camera: Option<horizon_shaders::Shadow>,
+    shadow_camera: Option<horizon_render_pipeline::Shadow>,
    /// Whether the pack's material reads `reflection` (`NativePack::new`): else no mirror
    /// is drawn and `has_reflection` stays 0.
    pub reflects: bool,
@@ -1014,10 +1014,9 @@ impl NativePost {
            texture_entry(11, wgpu::TextureSampleType::Uint),
        ];
        entries.extend(pack_texture_entries(frame.textures.len()));
-        entries
-            .extend((0..targets.len() as u32).map(|j| {
-                texture_entry(horizon_shader_api::stages::POST_TARGET_BINDING + j, float)
-            }));
+        entries.extend(
+            (0..targets.len() as u32).map(|j| texture_entry(POST_TARGET_BINDING + j, float)),
+        );
        let layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
            label: Some("Native shader pack post"),
            entries: &entries,
@@ -1346,7 +1345,7 @@ impl NativePost {
                        view
                    };
                    wgpu::BindGroupEntry {
-                        binding: horizon_shader_api::stages::POST_TARGET_BINDING + j as u32,
+                        binding: POST_TARGET_BINDING + j as u32,
                        resource: wgpu::BindingResource::TextureView(view),
                    }
                }));
@@ -1497,7 +1496,7 @@ pub fn frame_inputs(
    size: [u32; 2],
    seconds: f32,
    index: u32,
-    shadow: Option<&horizon_shaders::Shadow>,
+    shadow: Option<&horizon_render_pipeline::Shadow>,
 ) -> FrameInputs {
    let aspect = size[0] as f32 / size[1].max(1) as f32;
    let view = crate::camera::view_matrix(frame.yaw, frame.pitch);
@@ -1655,7 +1654,7 @@ pub fn pack_textures(

 /// Layout entries of `count` pack textures and their samplers.
 pub(super) fn pack_texture_entries(count: usize) -> Vec<wgpu::BindGroupLayoutEntry> {
-    use horizon_shader_api::stages::{TEXTURE_BINDING, TEXTURE_SAMPLER_BINDING};
+    use horizon_render_pipeline::stages::{TEXTURE_BINDING, TEXTURE_SAMPLER_BINDING};
    (0..count as u32)
        .flat_map(|i| {
            [
@@ -1684,7 +1683,7 @@ pub(super) fn pack_texture_entries(count: usize) -> Vec<wgpu::BindGroupLayoutEnt
 pub(super) fn pack_texture_group_entries(
    textures: &[(wgpu::TextureView, wgpu::Sampler)],
 ) -> Vec<wgpu::BindGroupEntry<'_>> {
-    use horizon_shader_api::stages::{TEXTURE_BINDING, TEXTURE_SAMPLER_BINDING};
+    use horizon_render_pipeline::stages::{TEXTURE_BINDING, TEXTURE_SAMPLER_BINDING};
    textures
        .iter()
        .enumerate()
@@ -2677,8 +2676,7 @@ file = \"b.wgsl\"

    /// On the layered HDR frame a 0.2 pack's light is tone mapped once: by Horizon's curve,
    /// the one HDR without a pack uses, when the pack has no `[tonemap]`, else by the pack's
-    /// alone, held to the headroom. In SDR Horizon's is a clip at white. An HDR output switched
-    /// to scRGB and back to HDR10 (`Hdr::retargeted`) maps it once all the same.
+    /// alone, held to the headroom. In SDR Horizon's is a clip at white.
    #[test]
    fn a_0_2_pack_is_tone_mapped_once_by_its_own_curve_or_horizons() {
        let Some((device, queue)) = device() else {
@@ -2688,9 +2686,8 @@ file = \"b.wgsl\"
        let light = 8.0f32;
        let (paper, peak) = (203.0, 1000.0);
        let headroom = peak / paper;
-        // The picture shown for that light, in linear light: (a pack's [tonemap], HDR, the
-        // output switched).
-        let shown = |pack_curve: bool, hdr: bool, switched: bool| {
+        // The picture shown for that light, in linear light: (a pack's [tonemap], HDR).
+        let shown = |pack_curve: bool, hdr: bool| {
            let (stage, file, source) = if pack_curve {
                (
                    "[tonemap]",
@@ -2748,11 +2745,6 @@ file = \"b.wgsl\"
                true,
            );
            (display.paper_white, display.peak) = (paper, peak);
-            if switched {
-                use super::super::hdr::Output::{Pq, ScRgb};
-                display = display.retargeted(&device, &queue, ScRgb);
-                display = display.retargeted(&device, &queue, Pq);
-            }
            let screen = display.frame(&device, [4, 4]);
            let usage =
                wgpu::TextureUsages::RENDER_ATTACHMENT | wgpu::TextureUsages::TEXTURE_BINDING;
@@ -2820,16 +2812,14 @@ file = \"b.wgsl\"
        // Horizon's curve once: BT.2390's EETF at 203 and 1000 nits puts light 8 at 4.82
        // (worked out apart from the shader, as in the HDR tone curve's own test). Clipped at
        // the headroom first, or mapped twice, it would land lower.
-        for switched in [false, true] {
-            let horizon = shown(false, true, switched);
-            assert!(near(horizon, 4.82043), "{switched}: {horizon}");
-            // The pack's identity curve alone: the light held to the headroom, not eased again.
-            let pack = shown(true, true, switched);
-            assert!(near(pack, headroom), "{switched}: {pack}");
-        }
+        let horizon = shown(false, true);
+        assert!(near(horizon, 4.82043), "{horizon}");
+        // The pack's identity curve alone: the light held to the headroom, not eased again.
+        let pack = shown(true, true);
+        assert!(near(pack, headroom), "{pack}");
        // SDR: a clip at white, the pack's or Horizon's.
        for pack_curve in [false, true] {
-            let sdr = shown(pack_curve, false, false);
+            let sdr = shown(pack_curve, false);
            assert!(near(sdr, 1.0), "{pack_curve}: {sdr}");
        }
    }
@@ -11,9 +11,9 @@ use std::sync::{
    atomic::{AtomicBool, Ordering},
 };

-/// The hooks' trait and dispatch, made from `native-hooks.json` by `cargo run -p xtask -- mod-api`;
-/// the game's build checks that the file is current.
-mod generated;
+mod generated {
+    include!(concat!(env!("OUT_DIR"), "/native_render_generated.rs"));
+}
 pub use generated::{
    HandDrawnEvent, RenderHooks, RenderNeedsEvent, WorldDrawnEvent, WorldWarpEvent,
 };
@@ -1,71 +0,0 @@
-// @generated by cargo run -p xtask -- mod-api; do not edit.
-use super::*;
-pub trait RenderHooks: Send + Sync {
-    /// The world is drawn (see [`WorldDrawn`]). Not called on the title screen's panorama.
-    fn world_drawn(&self, event: &mut WorldDrawnEvent<'_, '_>) {
-        let _ = event;
-    }
-    /// Asked as a frame is built and drawn: set what your mod needs.
-    ///
-    /// Every mod gets `event.needs` in order and may add, change or remove needs.
-    fn render_needs(&self, event: &mut RenderNeedsEvent<'_>) {
-        let _ = event;
-    }
-    /// The first-person hand is drawn (see [`HandDrawn`]), on every frame [`native_world_drawn`]
-    /// runs, with no hand too. API 364.
-    fn hand_drawn(&self, event: &mut HandDrawnEvent<'_, '_>) {
-        let _ = event;
-    }
-    /// Asked once a frame, before the world is drawn (not on the title screen's panorama): set
-    /// [`WorldWarp`] to have the frame drawn through your warp. Mods are asked in order and one warp
-    /// draws: the last one set. Keep it cheap: compare and reuse your `Arc<str>`.
-    ///
-    /// Every mod gets `event.warp` in order and may add, change or remove warp.
-    fn world_warp(&self, event: &mut WorldWarpEvent<'_>) {
-        let _ = event;
-    }
-}
-/// What [`RenderHooks::world_drawn`] is told. Fields may be added: the struct is `#[non_exhaustive]`.
-#[non_exhaustive]
-pub struct WorldDrawnEvent<'a, 'b> {
-    pub world: &'a mut WorldDrawn<'b>,
-}
-pub fn dispatch_world_drawn(mods: &[&dyn RenderHooks], world: &mut WorldDrawn<'_>) {
-    let mut event = WorldDrawnEvent { world };
-    for mod_hook in mods {
-        mod_hook.world_drawn(&mut event);
-    }
-}
-/// What [`RenderHooks::render_needs`] is told. Fields may be added: the struct is `#[non_exhaustive]`.
-#[non_exhaustive]
-pub struct RenderNeedsEvent<'a> {
-    pub needs: &'a mut RenderNeeds,
-}
-pub fn dispatch_render_needs(mods: &[&dyn RenderHooks], needs: &mut RenderNeeds) {
-    let mut event = RenderNeedsEvent { needs };
-    for mod_hook in mods {
-        mod_hook.render_needs(&mut event);
-    }
-}
-/// What [`RenderHooks::hand_drawn`] is told. Fields may be added: the struct is `#[non_exhaustive]`.
-#[non_exhaustive]
-pub struct HandDrawnEvent<'a, 'b> {
-    pub hand: &'a mut HandDrawn<'b>,
-}
-pub fn dispatch_hand_drawn(mods: &[&dyn RenderHooks], hand: &mut HandDrawn<'_>) {
-    let mut event = HandDrawnEvent { hand };
-    for mod_hook in mods {
-        mod_hook.hand_drawn(&mut event);
-    }
-}
-/// What [`RenderHooks::world_warp`] is told. Fields may be added: the struct is `#[non_exhaustive]`.
-#[non_exhaustive]
-pub struct WorldWarpEvent<'a> {
-    pub warp: &'a mut WorldWarp,
-}
-pub fn dispatch_world_warp(mods: &[&dyn RenderHooks], warp: &mut WorldWarp) {
-    let mut event = WorldWarpEvent { warp };
-    for mod_hook in mods {
-        mod_hook.world_warp(&mut event);
-    }
-}
@@ -6,8 +6,9 @@
 //! draw lists (`ShadowView`) serve both; the map's texels are distorted toward the camera as the
 //! prelude's `shadow_position` undoes.

-use horizon_shader_api::{Api, Frame as FrameInputs, manifest::Shadow as Settings, stages::GROUP};
-use horizon_shaders::Shadow;
+use horizon_render_pipeline::Shadow;
+use horizon_render_pipeline::{Api, Frame as FrameInputs, stages::GROUP};
+use horizon_shader_api::manifest::Shadow as Settings;

 use super::native_material::TerrainShape;
 use super::wgsl_prefix::{TERRAIN, prefixed, section};
@@ -387,7 +388,7 @@ fn entity_source() -> String {
    format!(
        "{}@group({GROUP}) @binding(0) var<uniform> frame: Frame;\n{}{ENTITY_ENTRIES}",
        FrameInputs::WGSL.wgsl(),
-        horizon_shader_api::stages::SHADOW_HELPERS,
+        horizon_render_pipeline::stages::SHADOW_HELPERS,
    )
 }

@@ -486,7 +487,7 @@ fn shader_source(
        (Some(material), _) => (
            format!(
                "{material}{}{table}{}{}{GRID_ENTRIES}",
-                horizon_shader_api::stages::PBR_STUB,
+                horizon_render_pipeline::stages::PBR_STUB,
                super::displace::RELIEF,
                super::displace::GRID,
            ),
@@ -504,7 +505,7 @@ fn shader_source(
            format!(
                "{}@group({GROUP}) @binding(0) var<uniform> frame: Frame;\n{}{UNTAKEN}",
                FrameInputs::WGSL.wgsl(),
-                horizon_shader_api::stages::SHADOW_HELPERS,
+                horizon_render_pipeline::stages::SHADOW_HELPERS,
            ),
            super::native_material::DISPLACE_VANILLA,
        ),
@@ -6,7 +6,8 @@
 //! names). It reads the renderer's globals (group 0) and the pack's frame (group 3), and
 //! draws where vanilla's sky draws; the sun, moon, stars and the dark disc are drawn over it.

-use horizon_shader_api::{check::CheckedStage, stages::GROUP};
+use horizon_render_pipeline::stages::GROUP;
+use horizon_shader_api::check::CheckedStage;

 use super::native_post::{NativeFrame, present_constants};
 use super::wgsl_prefix::{TERRAIN, prefixed, section};
@@ -40,7 +41,7 @@ fn vanilla_sky() -> String {
 }

 /// The sky shader for the pack's sky stage `source`.
-fn shader_source(source: &str, api: horizon_shader_api::Api) -> String {
+fn shader_source(source: &str, api: horizon_render_pipeline::Api) -> String {
    format!(
        "{source}\n// Horizon's sky (terrain.wgsl)\n{}{}{PACK_ENTRY}",
        vanilla_sky(),
@@ -198,7 +199,7 @@ mod tests {
        // A pack may use the renderer's names for its own things.
        let own = "override gain: f32;\nconst PI: f32 = 3.0;\nfn view_ray() -> f32 { return PI; }\n\
            fn sky(input: SkyInput) -> vec4<f32> { return input.color * gain * view_ray(); }\n";
-        let text = shader_source(&stage(own).source, horizon_shader_api::Api::V0_1);
+        let text = shader_source(&stage(own).source, horizon_render_pipeline::Api::V0_1);
        let module = naga::front::wgsl::parse_str(&text).unwrap_or_else(|e| {
            panic!("{}", e.emit_to_string(&text));
        });
@@ -261,7 +262,7 @@ mod tests {
            Vec::new(),
            Default::default(),
            None,
-            horizon_shader_api::Api::V0_1,
+            horizon_render_pipeline::Api::V0_1,
        );
        queue.write_buffer(
            &frame.buffer,
@@ -18,43 +18,6 @@ pub(crate) struct OutputCapabilities {
    pub float_frame: bool,
    /// The device keeps the HUD on a layer of its own (`hud_coverage::supported`).
    pub hud_layer: bool,
-    /// HDR output is held back: the last start on this window's graphics driver ended before
-    /// HDR output showed a frame ([`held`]). The mode stays; the output is SDR.
-    pub held: bool,
-}
-
-/// Whether HDR output is held back on a renderer whose window's graphics driver is `driver`
-/// (`None` offscreen, which never holds it back: only a window writes the marker).
-pub(crate) fn held(settings: &Graphics, driver: Option<&str>) -> bool {
-    driver.is_some_and(|driver| settings.hdr_held(driver))
-}
-
-/// The graphics driver this window's HDR output starts on ([`driver_fingerprint`]), with the
-/// system's version as crash reports name it (`crash::operating_system`), read once a run.
-pub(crate) fn window_driver(info: &wgpu::AdapterInfo) -> String {
-    static OS: std::sync::OnceLock<String> = std::sync::OnceLock::new();
-    driver_fingerprint(info, OS.get_or_init(crate::crash::operating_system))
-}
-
-/// The graphics driver a window's HDR output starts on, in one line: the backend, the
-/// adapter's vendor and device IDs and its name, the driver's name and its version, and the
-/// system's version `os`. Another GPU, a driver update or a system update reads differently:
-/// Metal names no driver, so on macOS the driver updates with the system.
-pub fn driver_fingerprint(info: &wgpu::AdapterInfo, os: &str) -> String {
-    let adapter = format!(
-        "{:?} {:04x}:{:04x} {}",
-        info.backend, info.vendor, info.device, info.name
-    );
-    [adapter.as_str(), &info.driver, &info.driver_info, os]
-        .map(|field| {
-            field
-                .chars()
-                .map(|c| if c.is_control() { ' ' } else { c })
-                .collect::<String>()
-                .trim()
-                .to_owned()
-        })
-        .join("; ")
 }

 /// What the system last reported for a renderer's display: its luminance, and whether it
@@ -134,15 +97,13 @@ pub struct EffectiveOutput {
    pub(crate) reported: Option<Reported>,
    /// The device draws the 16-bit frame (Smooth Gradients).
    pub(crate) wide_frame_supported: bool,
-    /// HDR output is held back on this window's graphics driver (`OutputCapabilities::held`).
-    pub(crate) held: bool,
    /// The HDR output presented; `None` is SDR.
    pub(crate) encoding: Option<Output>,
    pub(crate) frame: FrameConfiguration,
    /// Paper white, peak and black level in nits, as HDR output's last pass and its
    /// metadata take them, while it is on.
    pub(crate) nits: [f32; 3],
-    /// The HUD and menus' brightness, as a share of paper white: their nits over its.
+    /// The HUD and menus' brightness, as a share of paper white.
    pub(crate) ui_brightness: f32,
 }
 impl Default for EffectiveOutput {
@@ -157,7 +118,6 @@ impl EffectiveOutput {
        system_hdr: None,
        reported: None,
        wide_frame_supported: false,
-        held: false,
        encoding: None,
        frame: FrameConfiguration {
            format: wgpu::TextureFormat::Bgra8Unorm,
@@ -176,10 +136,9 @@ impl EffectiveOutput {
        self.encoding.is_some()
    }
    /// Whether `mode` asks for HDR here: On always, Auto where the destination offers it and
-    /// the display reports HDR, neither while HDR output is held back. The output still needs
-    /// an offer and a frame that can take it.
+    /// the display reports HDR. The output still needs an offer and a frame that can take it.
    pub fn requests_hdr(&self, mode: HdrMode) -> bool {
-        !self.held && requests_hdr(mode, self.offered.is_some(), self.system_hdr)
+        requests_hdr(mode, self.offered.is_some(), self.system_hdr)
    }
    /// What a 0.2 pack's `Frame` describes: the HDR display on the layered frame, whose
    /// picture is light; SDR otherwise, where the frame holds SDR's picture, the one HDR
@@ -210,10 +169,6 @@ fn requests_hdr(mode: HdrMode, offered: bool, system: Option<bool>) -> bool {
        HdrMode::Auto => offered && system == Some(true),
    }
 }
-/// Whether `settings` ask for HDR on a destination of `caps` whose display reports `reading`.
-fn wanted(settings: &Graphics, caps: OutputCapabilities, reading: DisplayReading) -> bool {
-    !caps.held && requests_hdr(settings.hdr, caps.hdr.is_some(), reading.hdr)
-}

 /// The frame a renderer made now draws in, for `settings`, the pack's `request`, what the
 /// destination and device can do (`caps`) and what the display reports.
@@ -224,7 +179,7 @@ pub(crate) fn resolve_frame(
    reading: DisplayReading,
    swapchain: wgpu::TextureFormat,
 ) -> FrameConfiguration {
-    let wanted = wanted(settings, caps, reading);
+    let wanted = requests_hdr(settings.hdr, caps.hdr.is_some(), reading.hdr);
    let (format, hud_layer) = super::frame_configuration(
        wanted && settings.hdr_smooth_gradients,
        (
@@ -255,13 +210,12 @@ pub(crate) fn resolve_output(
    frame: FrameConfiguration,
    presents: bool,
 ) -> EffectiveOutput {
-    let wanted = wanted(settings, caps, reading);
+    let wanted = requests_hdr(settings.hdr, caps.hdr.is_some(), reading.hdr);
    EffectiveOutput {
        offered: caps.hdr,
        system_hdr: reading.hdr,
        reported: reading.luminance,
        wide_frame_supported: caps.wide_frame,
-        held: caps.held,
        encoding: caps
            .hdr
            .filter(|_| wanted && presents && frame.overlay_format == frame.format),
@@ -271,8 +225,7 @@ pub(crate) fn resolve_output(
            settings.peak_nits(reading.luminance) as f32,
            settings.black_level_nits(),
        ],
-        ui_brightness: settings.ui_nits(reading.luminance) as f32
-            / settings.paper_white_nits(reading.luminance) as f32,
+        ui_brightness: settings.hdr_ui_brightness as f32 / 100.0,
    }
 }

@@ -294,7 +247,6 @@ pub(crate) mod tests {
                wide_frame: true,
                float_frame: true,
                hud_layer: true,
-                held: false,
            },
            DisplayReading {
                luminance: Some(Reported {
@@ -426,118 +378,6 @@ pub(crate) mod tests {
        assert_eq!(settings.hdr, HdrMode::On);
    }

-    /// A window on the driver a start failed on stays SDR, on an SDR frame, whatever the
-    /// mode, and the mode stays as chosen; another driver tries HDR again, and an offscreen
-    /// renderer (no driver) never holds HDR back.
-    #[test]
-    fn a_failed_start_holds_hdr_back_on_its_driver_only() {
-        let failed = "Vulkan 10de:2684 GPU; driver; 1.0";
-        for mode in [HdrMode::On, HdrMode::Auto] {
-            let settings = Graphics {
-                hdr: mode,
-                hdr_failed_start: Some(failed.into()),
-                ..Graphics::default()
-            };
-            let request = FrameRequest {
-                linear_pack: false,
-                hdr_float: true,
-            };
-            let on = |driver: Option<&str>| {
-                let (mut caps, reading) = window(Some(Output::Pq), Some(true));
-                caps.held = held(&settings, driver);
-                snapshot(&settings, request, caps, reading)
-            };
-            let out = on(Some(failed));
-            assert_eq!(out.encoding, None, "{mode:?}");
-            assert_eq!(out.frame.format, Bgra8Unorm, "{mode:?}");
-            assert!(!out.frame.hud_layer && out.held && !out.requests_hdr(mode));
-            // Still offered: the page lets the player pick a mode to try again.
-            assert!(out.hdr_offered());
-            assert_eq!(settings.hdr, mode);
-            for driver in [Some("Vulkan 10de:2684 GPU; driver; 1.1"), None] {
-                let out = on(driver);
-                assert_eq!(out.encoding, Some(Output::Pq), "{mode:?} {driver:?}");
-                assert_eq!(out.frame.format, LINEAR_FRAME, "{mode:?} {driver:?}");
-                assert!(!out.held && out.requests_hdr(mode));
-            }
-        }
-        // A marker that named no driver holds on whichever window comes first.
-        let legacy = Graphics {
-            hdr: HdrMode::On,
-            hdr_failed_start: Some(String::new()),
-            ..Graphics::default()
-        };
-        assert!(held(&legacy, Some(failed)));
-        assert!(!held(&legacy, None));
-    }
-
-    /// The fingerprint tells another GPU, backend, driver version or system version apart, in
-    /// one line.
-    #[test]
-    fn the_driver_fingerprint_is_one_line_that_changes_with_the_driver() {
-        let os = "windows (x86_64) version Windows 11 (26200.7019)";
-        let info = wgpu::AdapterInfo {
-            name: "NVIDIA GeForce RTX 4090".into(),
-            vendor: 0x10de,
-            device: 0x2684,
-            device_type: wgpu::DeviceType::DiscreteGpu,
-            device_pci_bus_id: "0000:01:00.0".into(),
-            driver: "NVIDIA".into(),
-            driver_info: "581.57\n".into(),
-            backend: wgpu::Backend::Vulkan,
-            subgroup_min_size: 32,
-            subgroup_max_size: 32,
-            transient_saves_memory: None,
-            limit_bucket: None,
-        };
-        let fingerprint = driver_fingerprint(&info, os);
-        assert_eq!(
-            fingerprint,
-            "Vulkan 10de:2684 NVIDIA GeForce RTX 4090; NVIDIA; 581.57; \
-             windows (x86_64) version Windows 11 (26200.7019)"
-        );
-        assert_ne!(
-            driver_fingerprint(&info, "windows (x86_64) version Windows 11 (26200.7171)"),
-            fingerprint
-        );
-        // Metal names no driver: a macOS update is what changes it.
-        let metal = wgpu::AdapterInfo {
-            name: "Apple M3".into(),
-            vendor: 0,
-            device: 0,
-            driver: String::new(),
-            driver_info: String::new(),
-            backend: wgpu::Backend::Metal,
-            ..info.clone()
-        };
-        let sonoma = driver_fingerprint(&metal, "macos (aarch64) version macOS 14.6");
-        assert_eq!(
-            sonoma,
-            "Metal 0000:0000 Apple M3; ; ; macos (aarch64) version macOS 14.6"
-        );
-        assert_ne!(
-            driver_fingerprint(&metal, "macos (aarch64) version macOS 15.1"),
-            sonoma
-        );
-        let other = [
-            wgpu::AdapterInfo {
-                driver_info: "582.02".into(),
-                ..info.clone()
-            },
-            wgpu::AdapterInfo {
-                backend: wgpu::Backend::Dx12,
-                ..info.clone()
-            },
-            wgpu::AdapterInfo {
-                device: 0x2704,
-                ..info.clone()
-            },
-        ];
-        for other in other {
-            assert_ne!(driver_fingerprint(&other, os), fingerprint, "{other:?}");
-        }
-    }
-
    /// Auto's paper white and peak are this display's report; the player's own values win.
    #[test]
    fn auto_levels_follow_this_renderers_report() {
@@ -567,39 +407,6 @@ pub(crate) mod tests {
        );
    }

-    /// UI Brightness reaches HDR output as its nits over paper white's: 1 on Auto, whatever
-    /// paper white is; a value set by hand holds its nits, Paper White on Auto or set by hand.
-    #[test]
-    fn ui_brightness_is_its_nits_over_paper_whites() {
-        let (caps, reading) = window(Some(Output::Pq), Some(true));
-        let share = |paper_white, ui_nits, reading| {
-            let settings = Graphics {
-                hdr: HdrMode::On,
-                hdr_paper_white: paper_white,
-                hdr_ui_nits: ui_nits,
-                ..Graphics::default()
-            };
-            let frame = resolve_frame(
-                &settings,
-                FrameRequest::default(),
-                caps,
-                reading,
-                Bgra8Unorm,
-            );
-            resolve_output(&settings, caps, reading, frame, true).ui_brightness
-        };
-        // Auto: the report's 400 nits, 203 without one, or the player's 250.
-        let unreported = DisplayReading::default();
-        for (paper_white, reading) in [(0, reading), (0, unreported), (250, reading)] {
-            assert_eq!(share(paper_white, 0, reading), 1.0);
-        }
-        assert_eq!(share(0, 100, reading), 0.25);
-        assert_eq!(share(0, 480, reading), 1.2);
-        assert_eq!(share(0, 406, unreported), 2.0);
-        assert_eq!(share(250, 100, reading), 0.4);
-        assert_eq!(share(250, 480, reading), 1.92);
-    }
-
    /// Two renderers' states, a window's and an offscreen one's, made and changed in turn:
    /// neither's offer or report shows in the other's snapshot, and the offscreen one
    /// stopping its watch (HDR Off) leaves the window's report alone.
@@ -1,942 +0,0 @@
-//! Applying the output a renderer resolves (`output::resolve_output`). Each observation of the
-//! settings, the destination's capabilities and the display resolves one candidate. One that
-//! changes only values (the luminance, the UI brightness, what the display reports) updates
-//! them in place. Another encoding or frame is built and the swapchain configured for it before
-//! the snapshot says so. One that fails is never published as active, and is not tried again
-//! until the request, the capabilities or the surface change. Auto keeps HDR on through a
-//! moment's loss of the display's report ([`auto_grace`]).
-use super::{DisplayReading, DisplayWatch, Renderer, hdr, output};
-use crate::graphics::HdrMode;
-use output::{EffectiveOutput, OutputCapabilities};
-use std::time::{Duration, Instant};
-
-/// What an output's resources are made for: the encoding presented and the frame.
-type Key = (Option<hdr::Output>, output::FrameConfiguration);
-fn key(output: &EffectiveOutput) -> Key {
-    (output.encoding, output.frame)
-}
-
-/// An output whose resources or swapchain configuration failed, with the capabilities it
-/// failed on.
-#[derive(Clone, Copy, Debug, PartialEq)]
-pub(super) struct Rejected {
-    key: Key,
-    caps: OutputCapabilities,
-}
-
-/// What applying an output changes in a renderer.
-trait Present {
-    /// Builds what `output` presents and configures the swapchain for it, then swaps the new
-    /// resources in. On an error the resources stay as they were, and the swapchain may be
-    /// configured for neither output.
-    fn present(&mut self, output: &EffectiveOutput) -> std::result::Result<(), String>;
-    /// Presents SDR whatever happens: a swapchain that doesn't configure now is configured
-    /// again before the next frame (`surface_unconfigured`).
-    fn present_sdr(&mut self);
-}
-
-/// The snapshot to publish for `candidate` after `applied`, on `caps`. The same resources
-/// take the candidate's values as they are. Other ones are presented first and published only
-/// once that worked. On a failure the output applied stays where it presents again, else
-/// SDR, and the failed one is kept in `rejected` until the candidate's resources or the
-/// capabilities change.
-fn commit(
-    target: &mut impl Present,
-    applied: &EffectiveOutput,
-    candidate: EffectiveOutput,
-    caps: OutputCapabilities,
-    rejected: &mut Option<Rejected>,
-) -> EffectiveOutput {
-    let wanted = key(&candidate);
-    if rejected.is_some_and(|r| r.key != wanted || r.caps != caps) {
-        *rejected = None;
-    }
-    if wanted == key(applied) {
-        return candidate;
-    }
-    let kept = EffectiveOutput {
-        encoding: applied.encoding,
-        ..candidate
-    };
-    if rejected.is_some() {
-        return kept;
-    }
-    let Err(e) = target.present(&candidate) else {
-        return candidate;
-    };
-    log::warn!(
-        "Horizon renderer: {} could not be presented ({e}); keeping {}",
-        name(candidate.encoding),
-        name(applied.encoding)
-    );
-    *rejected = Some(Rejected { key: wanted, caps });
-    if target.present(&kept).is_ok() {
-        return kept;
-    }
-    log::warn!(
-        "Horizon renderer: {} no longer presents; SDR",
-        name(kept.encoding)
-    );
-    target.present_sdr();
-    EffectiveOutput {
-        encoding: None,
-        ..candidate
-    }
-}
-
-fn name(encoding: Option<hdr::Output>) -> &'static str {
-    encoding.map_or("SDR", hdr::Output::name)
-}
-
-/// The swapchain's configuration for `encoding`: `config` (what every pipeline draws in), or
-/// HDR10 or scRGB.
-pub(super) fn surface_config(
-    config: &wgpu::SurfaceConfiguration,
-    encoding: Option<hdr::Output>,
-) -> wgpu::SurfaceConfiguration {
-    let mut config = config.clone();
-    if let Some(output) = encoding {
-        config.format = output.format();
-        config.view_formats = vec![output.format()];
-        config.color_space = output.color_space();
-        config.usage = wgpu::TextureUsages::RENDER_ATTACHMENT;
-    }
-    config
-}
-
-/// How long Auto keeps HDR on once the display stops reporting it. A fixed window that
-/// coalesces the report's churn as a display wakes or the window moves to another one; not a
-/// measured sleep/wake time.
-const AUTO_OFF_DELAY: Duration = Duration::from_millis(500);
-
-/// The display's report `update_output` resolves Auto with at `now`. While Auto presents HDR
-/// and the surface still offers that encoding, a report that turns false or unknown starts
-/// the timer `since`, once, and HDR stays on at the values last applied until it has held
-/// for [`AUTO_OFF_DELAY`]; a positive report before then clears it. Off and On, a changed
-/// offer, and entering HDR take `raw` at once.
-fn auto_grace(
-    now: Instant,
-    mode: HdrMode,
-    offered: Option<hdr::Output>,
-    raw: DisplayReading,
-    applied: &EffectiveOutput,
-    since: &mut Option<Instant>,
-) -> DisplayReading {
-    let lost = mode == HdrMode::Auto
-        && applied.encoding.is_some()
-        && offered == applied.encoding
-        && raw.hdr != Some(true);
-    if !lost {
-        if since.take().is_some() && raw.hdr == Some(true) {
-            log::info!("Horizon renderer: the display reports HDR again; HDR stays on");
-        }
-    } else if since.is_none() {
-        log::info!(
-            "Horizon renderer: the display stopped reporting HDR; Auto keeps it on for {} ms",
-            AUTO_OFF_DELAY.as_millis()
-        );
-        *since = Some(now);
-    } else if grace_over(*since, now) {
-        *since = None;
-    }
-    graced(*since, raw, applied)
-}
-
-fn grace_over(since: Option<Instant>, now: Instant) -> bool {
-    since.is_some_and(|since| now.saturating_duration_since(since) >= AUTO_OFF_DELAY)
-}
-
-/// What the display reports as the output takes it: during Auto's grace (`since`), HDR at the
-/// luminance `applied` was resolved with; `raw` otherwise.
-pub(super) fn graced(
-    since: Option<Instant>,
-    raw: DisplayReading,
-    applied: &EffectiveOutput,
-) -> DisplayReading {
-    match since {
-        Some(_) => DisplayReading {
-            luminance: applied.reported,
-            hdr: Some(true),
-        },
-        None => raw,
-    }
-}
-
-/// Whether the output resolves again at `now`: a due poll (`read`, with the surface's
-/// `offer`; on Wayland, an event) changed `reading` or `caps`, or Auto's grace `since` is
-/// over. Its end reads the display once more first, however long until the next poll, unless
-/// a read since the deadline did (the last read is a `DISPLAY_POLL` before the next).
-fn poll_display(
-    watch: Option<&mut DisplayWatch>,
-    reading: &mut DisplayReading,
-    caps: &mut OutputCapabilities,
-    since: Option<Instant>,
-    now: Instant,
-    read: impl FnOnce() -> DisplayReading,
-    offer: impl FnOnce() -> Option<Option<hdr::Output>>,
-) -> bool {
-    let over = grace_over(since, now);
-    let Some(watch) = watch else {
-        return over;
-    };
-    if let (Some(since), Some(next)) = (since.filter(|_| over), &mut watch.polled)
-        && *next < since + AUTO_OFF_DELAY + super::DISPLAY_POLL
-    {
-        *next = now;
-    }
-    let Some(read) = watch.poll(*reading, now, read) else {
-        return over;
-    };
-    observe(reading, caps, read, offer()) || over
-}
-
-/// What `surface` offers now (`None` offscreen): Vulkan's offered formats can change with
-/// desktop HDR or the window's output, and a display can offer the other encoding.
-fn offer(surface: Option<&wgpu::Surface>, adapter: &wgpu::Adapter) -> Option<Option<hdr::Output>> {
-    Some(hdr::output(&surface?.get_capabilities(adapter)))
-}
-
-/// Takes what a due poll read into `reading` and `caps`: the display's report `now`, and what
-/// the surface offers (`offer`, `None` without a surface). Whether either changed, the offer
-/// alone included.
-fn observe(
-    reading: &mut DisplayReading,
-    caps: &mut OutputCapabilities,
-    now: DisplayReading,
-    offer: Option<Option<hdr::Output>>,
-) -> bool {
-    let before = (*reading, caps.hdr);
-    *reading = now;
-    if let Some(offer) = offer {
-        caps.hdr = offer;
-    }
-    before != (*reading, caps.hdr)
-}
-
-/// A renderer applying an output, with the marker its HDR output's start writes.
-struct Applying<'a> {
-    renderer: &'a mut Renderer,
-    marker: &'a std::path::Path,
-}
-
-impl Present for Applying<'_> {
-    fn present(&mut self, output: &EffectiveOutput) -> std::result::Result<(), String> {
-        let r = &mut *self.renderer;
-        let current = r.hdr.as_ref().map(|hdr| hdr.output);
-        let switching = output.encoding.is_some_and(|e| current != Some(e));
-        // If the game dies before HDR output shows a frame, its pipelines' build included, the
-        // marker is still there at the next start, which then holds HDR output back on this
-        // driver.
-        if output.encoding.is_none() || switching {
-            r.mark_hdr_start(output.encoding.is_some(), self.marker);
-        }
-        let built = match output.encoding {
-            Some(encoding) if switching => Some(r.build_hdr(encoding, output)?),
-            _ => None,
-        };
-        if let Some(surface) = &r.surface {
-            r.frame_gen.stop();
-            // The submit thread may still present to the old swapchain.
-            r.queue.wait();
-            let hdr = built.as_ref().or(r.hdr.as_ref());
-            Renderer::configure(
-                &r.device,
-                surface,
-                &surface_config(&r.config, output.encoding),
-                hdr.filter(|_| output.encoding.is_some()),
-                &r.device_lost,
-            )?;
-            r.surface_unconfigured = false;
-        }
-        if output.encoding.is_none() {
-            r.hdr = None;
-        } else if built.is_some() {
-            r.hdr = built;
-        }
-        Ok(())
-    }
-
-    fn present_sdr(&mut self) {
-        let r = &mut *self.renderer;
-        r.hdr = None;
-        r.mark_hdr_start(false, self.marker);
-        if let Some(surface) = &r.surface {
-            r.frame_gen.stop();
-            r.queue.wait();
-            r.surface_unconfigured =
-                Renderer::configure(&r.device, surface, &r.config, None, &r.device_lost).is_err();
-        }
-    }
-}
-
-impl Renderer {
-    /// HDR output presenting `encoding` for `output`, made apart from the one presented: from
-    /// it where there is one, keeping the player's tuning (`Hdr::retargeted`). An error is
-    /// the device's, caught here rather than left for the next frame.
-    fn build_hdr(
-        &self,
-        encoding: hdr::Output,
-        output: &EffectiveOutput,
-    ) -> std::result::Result<hdr::Hdr, String> {
-        let validation = self.device.push_error_scope(wgpu::ErrorFilter::Validation);
-        let memory = self.device.push_error_scope(wgpu::ErrorFilter::OutOfMemory);
-        let mut hdr = match &self.hdr {
-            Some(hdr) => hdr.retargeted(&self.device, &self.queue, encoding),
-            None => {
-                let mut hdr = hdr::Hdr::new(
-                    &self.device,
-                    &self.queue,
-                    output.frame.format,
-                    encoding,
-                    output.frame.hud_layer,
-                );
-                hdr.look = self.hdr_lighting_setting;
-                hdr
-            }
-        };
-        let memory = pollster::block_on(memory.pop());
-        if let Some(e) = memory.or(pollster::block_on(validation.pop())) {
-            return Err(e.to_string());
-        }
-        // The metadata the swapchain's configuration sends.
-        [hdr.paper_white, hdr.peak, hdr.black] = output.nits;
-        hdr.ui = output.ui_brightness;
-        Ok(hdr)
-    }
-
-    /// HDR output (Horizon setting) as `settings` ask for it on this renderer's frame
-    /// (`output::resolve_output`): HDR10 or scRGB at paper white, the world's highlights
-    /// expanded up to the peak. Off where the surface can't present it. Offscreen
-    /// (`hdr::offscreen_output`) the frame is drawn the same and its HDR screenshot taken,
-    /// but nothing is presented, and Auto takes its defaults: no display reports.
-    pub fn update_output(
-        &mut self,
-        settings: &crate::graphics::Graphics,
-        marker: &std::path::Path,
-    ) {
-        let now = Instant::now();
-        self.watch_hdr(settings.hdr);
-        // Auto's grace ends on a fresh read, also where a settings change comes before the
-        // frame's `display_changed`.
-        if grace_over(self.auto_off_since, now) {
-            self.read_display(now);
-        }
-        self.hold_hdr_back(settings);
-        let reading = auto_grace(
-            now,
-            settings.hdr,
-            self.output_caps.hdr,
-            self.reading,
-            &self.output,
-            &mut self.auto_off_since,
-        );
-        let candidate = output::resolve_output(
-            settings,
-            self.output_caps,
-            reading,
-            self.output.frame,
-            self.surface.is_some() || self.offscreen.is_some(),
-        );
-        let (applied, caps) = (self.output, self.output_caps);
-        let mut rejected = self.output_rejected.take();
-        let renderer = &mut Applying {
-            renderer: self,
-            marker,
-        };
-        let next = commit(renderer, &applied, candidate, caps, &mut rejected);
-        self.output_rejected = rejected;
-        let [paper_white, peak, black] = next.nits;
-        if next.encoding != applied.encoding {
-            match next.encoding {
-                Some(output) => log::info!(
-                    "Horizon renderer: HDR on: {} ({:?}), {paper_white}/{peak} nits",
-                    output.name(),
-                    output.format()
-                ),
-                None => log::info!("Horizon renderer: HDR off"),
-            }
-            self.measure_emission();
-        }
-        if let Some(hdr) = &mut self.hdr {
-            hdr.ui = next.ui_brightness;
-            if (hdr.paper_white, hdr.peak, hdr.black) != (paper_white, peak, black) {
-                (hdr.paper_white, hdr.peak, hdr.black) = (paper_white, peak, black);
-                self.send_hdr_metadata();
-            }
-        }
-        self.output = next;
-    }
-
-    /// Follows the selected mode even when Auto currently wants SDR. Off never asks
-    /// the system about the display; selecting On or Auto starts a fresh watch.
-    fn watch_hdr(&mut self, mode: crate::graphics::HdrMode) {
-        if mode == crate::graphics::HdrMode::Off {
-            self.display = None;
-            self.display_fresh = false;
-            self.reading.stop_watching();
-        } else if self.display.is_none() {
-            let (watch, now) =
-                DisplayWatch::new(&self.window, self.surface.as_deref(), &self.adapter);
-            self.display = Some(watch);
-            let offer = offer(self.surface.as_deref(), &self.adapter);
-            self.output_caps.hdr = offer.unwrap_or(self.output_caps.hdr);
-            self.reading = now;
-            self.display_fresh = true;
-        }
-    }
-
-    /// The swapchain's configuration: `config` (what every pipeline draws in), or
-    /// HDR10 or scRGB while HDR output is on.
-    pub(super) fn surface_config(&self) -> wgpu::SurfaceConfiguration {
-        surface_config(&self.config, self.hdr.as_ref().map(|hdr| hdr.output))
-    }
-
-    /// After a new window surface: what it offers, and an output that failed on the old one
-    /// may be tried again. The settings apply again.
-    pub(super) fn surface_recreated(&mut self) {
-        let offer = offer(self.surface.as_deref(), &self.adapter);
-        self.output_caps.hdr = offer.unwrap_or(self.output_caps.hdr);
-        self.display_fresh = true;
-        self.output_rejected = None;
-    }
-
-    /// Whether what the system reports for the display, or what the surface offers, changed
-    /// (another output, the player recalibrating the desktop, desktop HDR offering the other
-    /// encoding): the settings' Auto values and the output follow it then, so apply them
-    /// again. Each due poll reads the surface's capabilities as well, even when the display
-    /// reports the same. So does the end of Auto's grace (`auto_grace`), with or without a
-    /// poll or an event then.
-    pub fn display_changed(&mut self) -> bool {
-        super::flush_display_log();
-        if std::mem::take(&mut self.display_fresh) {
-            return true;
-        }
-        self.read_display(Instant::now())
-    }
-
-    /// The display read where a poll is due or Auto's grace is over (`poll_display`).
-    fn read_display(&mut self, now: Instant) -> bool {
-        let (surface, adapter) = (self.surface.as_deref(), &self.adapter);
-        poll_display(
-            self.display.as_mut(),
-            &mut self.reading,
-            &mut self.output_caps,
-            self.auto_off_since,
-            now,
-            || DisplayReading::read(surface, adapter),
-            || offer(surface, adapter),
-        )
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::graphics::{Graphics, HdrMode, Reported};
-    use hdr::Output::{Pq, ScRgb};
-    use output::FrameRequest;
-    use output::tests::{snapshot, window};
-
-    /// A swapchain that records what it was asked to present, and fails `fails`.
-    #[derive(Default)]
-    struct Swapchain {
-        fails: Vec<Option<hdr::Output>>,
-        /// Each encoding presented, with the luminance its metadata sends.
-        asked: Vec<(Option<hdr::Output>, [f32; 3])>,
-        sdr: usize,
-    }
-    impl Present for Swapchain {
-        fn present(&mut self, output: &EffectiveOutput) -> std::result::Result<(), String> {
-            self.asked.push((output.encoding, output.nits));
-            if self.fails.contains(&output.encoding) {
-                return Err("unsupported".into());
-            }
-            Ok(())
-        }
-        fn present_sdr(&mut self) {
-            self.sdr += 1;
-        }
-    }
-
-    const NO_PACK: FrameRequest = FrameRequest {
-        linear_pack: false,
-        hdr_float: true,
-    };
-    fn on() -> Graphics {
-        Graphics {
-            hdr: HdrMode::On,
-            ..Graphics::default()
-        }
-    }
-    /// The candidate on a renderer whose frame is `applied`'s.
-    fn candidate(
-        settings: &Graphics,
-        caps: OutputCapabilities,
-        reading: DisplayReading,
-        applied: &EffectiveOutput,
-    ) -> EffectiveOutput {
-        output::resolve_output(settings, caps, reading, applied.frame, true)
-    }
-
-    /// HDR stays on while the display offers scRGB instead of HDR10 and then HDR10 again:
-    /// the swapchain, its metadata and the snapshot follow each, with no Off between.
-    #[test]
-    fn the_output_follows_pq_to_scrgb_and_back_while_hdr_stays_on() {
-        let settings = on();
-        let (mut caps, reading) = window(Some(Pq), Some(true));
-        let mut applied = snapshot(&settings, NO_PACK, caps, reading);
-        assert_eq!(applied.encoding, Some(Pq));
-        let (mut swapchain, mut rejected) = (Swapchain::default(), None);
-        for encoding in [ScRgb, Pq] {
-            caps.hdr = Some(encoding);
-            let next = candidate(&settings, caps, reading, &applied);
-            applied = commit(&mut swapchain, &applied, next, caps, &mut rejected);
-            assert_eq!(
-                (applied.encoding, applied.offered),
-                (Some(encoding), Some(encoding))
-            );
-            assert_eq!(
-                applied.frame,
-                snapshot(&settings, NO_PACK, caps, reading).frame
-            );
-        }
-        let metadata = [400.0, 1000.0, 0.0];
-        assert_eq!(
-            swapchain.asked,
-            [(Some(ScRgb), metadata), (Some(Pq), metadata)]
-        );
-        assert_eq!((rejected, swapchain.sdr), (None, 0));
-    }
-
-    /// The display reports the same luminance and HDR, but the surface now offers scRGB: the
-    /// next due poll reads it, and the output follows with the same nits and report.
-    #[test]
-    fn a_change_of_offer_alone_is_seen_at_the_next_poll() {
-        let settings = on();
-        let (mut caps, mut reading) = window(Some(Pq), Some(true));
-        let applied = snapshot(&settings, NO_PACK, caps, reading);
-        let start = std::time::Instant::now();
-        let mut watch = DisplayWatch {
-            #[cfg(target_os = "linux")]
-            wayland: None,
-            polled: Some(start + super::super::DISPLAY_POLL),
-        };
-        let same = reading;
-        assert_eq!(watch.poll(reading, start, || unreachable!()), None);
-        let due = start + super::super::DISPLAY_POLL;
-        assert_eq!(watch.poll(reading, due, || same), Some(same));
-        assert_eq!(watch.polled, Some(due + super::super::DISPLAY_POLL));
-        assert!(observe(&mut reading, &mut caps, same, Some(Some(ScRgb))));
-        // Nothing changed at the next poll, and offscreen nothing is offered to read.
-        assert!(!observe(&mut reading, &mut caps, same, Some(Some(ScRgb))));
-        assert!(!observe(&mut reading, &mut caps, same, None));
-        let next = candidate(&settings, caps, reading, &applied);
-        let published = commit(&mut Swapchain::default(), &applied, next, caps, &mut None);
-        assert_eq!(published.encoding, Some(ScRgb));
-        assert_eq!(
-            (published.nits, published.reported, published.system_hdr),
-            (applied.nits, applied.reported, applied.system_hdr)
-        );
-    }
-
-    /// The display's luminance or the UI brightness change on the same output: the values
-    /// follow, and nothing is built or configured again.
-    #[test]
-    fn new_nits_on_the_same_output_build_nothing() {
-        let mut settings = on();
-        let (caps, mut reading) = window(Some(Pq), Some(true));
-        let applied = snapshot(&settings, NO_PACK, caps, reading);
-        reading.luminance = Some(Reported {
-            paper_white: 250,
-            peak: 600,
-        });
-        // 150 nits under the reported paper white of 250: 0.6 of it.
-        settings.hdr_ui_nits = 150;
-        let mut swapchain = Swapchain::default();
-        let next = candidate(&settings, caps, reading, &applied);
-        let published = commit(&mut swapchain, &applied, next, caps, &mut None);
-        assert_eq!(published, next);
-        assert_eq!(published.nits, [250.0, 600.0, 0.0]);
-        assert_eq!(published.ui_brightness, 0.6);
-        assert!(swapchain.asked.is_empty());
-    }
-
-    /// An encoding that fails is never the snapshot's: the output applied stays where it
-    /// presents again, else SDR. It is not tried again each frame, nor for new nits, only
-    /// once the request or the capabilities change.
-    #[test]
-    fn an_output_that_fails_is_never_active_nor_tried_every_frame() {
-        let settings = on();
-        let (mut caps, mut reading) = window(Some(Pq), Some(true));
-        let pq = snapshot(&settings, NO_PACK, caps, reading);
-        caps.hdr = Some(ScRgb);
-        let mut swapchain = Swapchain {
-            fails: vec![Some(ScRgb)],
-            ..Default::default()
-        };
-        let mut rejected = None;
-        let next = candidate(&settings, caps, reading, &pq);
-        let published = commit(&mut swapchain, &pq, next, caps, &mut rejected);
-        assert_eq!(published.encoding, Some(Pq));
-        assert_eq!(swapchain.asked.len(), 2, "scRGB, then HDR10 again");
-        // Frames after, and a new luminance: no new attempt.
-        for paper_white in [400, 400, 300] {
-            reading.luminance = Some(Reported {
-                paper_white,
-                peak: 1000,
-            });
-            let next = candidate(&settings, caps, reading, &published);
-            let again = commit(&mut swapchain, &published, next, caps, &mut rejected);
-            assert_eq!(again.encoding, Some(Pq));
-            assert_eq!(again.nits[0], paper_white as f32);
-        }
-        assert_eq!(swapchain.asked.len(), 2);
-        // Another request (HDR Off, then On) tries it again.
-        let off = Graphics::default();
-        let sdr = commit(
-            &mut swapchain,
-            &published,
-            candidate(&off, caps, reading, &published),
-            caps,
-            &mut rejected,
-        );
-        assert_eq!((sdr.encoding, rejected), (None, None));
-        let next = candidate(&settings, caps, reading, &sdr);
-        assert_eq!(
-            commit(&mut swapchain, &sdr, next, caps, &mut rejected).encoding,
-            None
-        );
-        assert_eq!(
-            swapchain.asked.iter().map(|a| a.0).collect::<Vec<_>>(),
-            [Some(ScRgb), Some(Pq), None, Some(ScRgb), None]
-        );
-        // So does another capability (the hold lifted here stands for any).
-        caps.held = true;
-        let held = candidate(&settings, caps, reading, &sdr);
-        assert_eq!(held.encoding, None);
-        commit(&mut swapchain, &sdr, held, caps, &mut rejected);
-        caps.held = false;
-        let asked = swapchain.asked.len();
-        let next = candidate(&settings, caps, reading, &sdr);
-        commit(&mut swapchain, &sdr, next, caps, &mut rejected);
-        assert_eq!(swapchain.asked.len(), asked + 2);
-        // The output applied failing too: SDR, never the failed one.
-        let mut broken = Swapchain {
-            fails: vec![Some(ScRgb), Some(Pq)],
-            ..Default::default()
-        };
-        let next = candidate(&settings, caps, reading, &pq);
-        let published = commit(&mut broken, &pq, next, caps, &mut None);
-        assert_eq!((published.encoding, broken.sdr), (None, 1));
-        assert_eq!(settings.hdr, HdrMode::On, "the mode stays");
-        // A new surface forgets the failure (`surface_recreated`): the same request on the
-        // same capabilities is tried again.
-        let mut swapchain = Swapchain {
-            fails: vec![Some(ScRgb)],
-            ..Default::default()
-        };
-        let mut rejected = None;
-        let next = candidate(&settings, caps, reading, &pq);
-        for _ in 0..2 {
-            commit(&mut swapchain, &pq, next, caps, &mut rejected);
-        }
-        assert_eq!(swapchain.asked.len(), 2);
-        rejected = None;
-        commit(&mut swapchain, &pq, next, caps, &mut rejected);
-        assert_eq!(swapchain.asked.len(), 4);
-    }
-
-    /// A window in Auto presenting HDR10 at 400/1000 nits on the layered frame, followed on
-    /// fake time as the game follows a renderer each frame: `display_changed`, then
-    /// `update_output` where it says so.
-    struct Auto {
-        settings: Graphics,
-        start: Instant,
-        watch: DisplayWatch,
-        reading: DisplayReading,
-        caps: OutputCapabilities,
-        applied: EffectiveOutput,
-        since: Option<Instant>,
-        swapchain: Swapchain,
-        /// What the system reports when it is read, and when (ms) it was.
-        report: DisplayReading,
-        reads: Vec<u64>,
-    }
-    impl Auto {
-        /// `polled`: the system is read every `DISPLAY_POLL` from 0, else it sends events
-        /// (`event`), as on Wayland.
-        fn new(polled: bool) -> Self {
-            let settings = Graphics {
-                hdr: HdrMode::Auto,
-                ..Graphics::default()
-            };
-            let (caps, reading) = window(Some(Pq), Some(true));
-            let applied = snapshot(&settings, NO_PACK, caps, reading);
-            assert!(applied.encoding == Some(Pq) && applied.frame.hud_layer);
-            let start = Instant::now();
-            Self {
-                settings,
-                start,
-                watch: DisplayWatch {
-                    #[cfg(target_os = "linux")]
-                    wayland: None,
-                    polled: polled.then_some(start),
-                },
-                reading,
-                caps,
-                applied,
-                since: None,
-                swapchain: Swapchain::default(),
-                report: reading,
-                reads: Vec::new(),
-            }
-        }
-        /// A frame at `ms`.
-        fn frame(&mut self, ms: u64) {
-            if self.read_display(ms) {
-                self.update(ms);
-            }
-        }
-        /// `Renderer::read_display` at `ms`.
-        fn read_display(&mut self, ms: u64) -> bool {
-            let now = self.start + Duration::from_millis(ms);
-            let (report, offer, reads) = (self.report, Some(self.caps.hdr), &mut self.reads);
-            let read = || {
-                reads.push(ms);
-                report
-            };
-            let (reading, caps) = (&mut self.reading, &mut self.caps);
-            poll_display(
-                Some(&mut self.watch),
-                reading,
-                caps,
-                self.since,
-                now,
-                read,
-                || offer,
-            )
-        }
-        /// Frames from `from` to `to` ms, every 10 ms.
-        fn frames(&mut self, from: u64, to: u64) {
-            for ms in (from..=to).step_by(10) {
-                self.frame(ms);
-            }
-        }
-        /// What the system reports from `ms` on: HDR `hdr`, with no luminance unless it is
-        /// HDR, at 300/800 nits then.
-        fn reports(&mut self, hdr: Option<bool>, offer: Option<hdr::Output>) {
-            self.report = DisplayReading {
-                luminance: (hdr == Some(true)).then_some(Reported {
-                    paper_white: 300,
-                    peak: 800,
-                }),
-                hdr,
-            };
-            self.caps.hdr = offer;
-        }
-        /// The system's event at `ms`, with what it now `reports`.
-        fn event(&mut self, ms: u64, hdr: Option<bool>, offer: Option<hdr::Output>) {
-            self.reports(hdr, offer);
-            self.reading = self.report;
-            self.update(ms);
-        }
-        /// `update_output` at `ms`, in its order.
-        fn update(&mut self, ms: u64) {
-            let now = self.start + Duration::from_millis(ms);
-            if grace_over(self.since, now) {
-                self.read_display(ms);
-            }
-            let applied = &self.applied;
-            let reading = auto_grace(
-                now,
-                self.settings.hdr,
-                self.caps.hdr,
-                self.reading,
-                applied,
-                &mut self.since,
-            );
-            let next = candidate(&self.settings, self.caps, reading, applied);
-            self.applied = commit(&mut self.swapchain, applied, next, self.caps, &mut None);
-            // While HDR stays on, the frame the game asks for (`Renderer::requested_frame`) is
-            // this one: no new renderer.
-            let reading = graced(self.since, self.reading, &self.applied);
-            let frame = output::resolve_frame(
-                &self.settings,
-                NO_PACK,
-                self.caps,
-                reading,
-                wgpu::TextureFormat::Bgra8UnormSrgb,
-            );
-            assert_eq!(
-                frame == self.applied.frame,
-                self.applied.hdr_on(),
-                "{ms} ms"
-            );
-        }
-        fn presented(&self) -> Vec<Option<hdr::Output>> {
-            self.swapchain.asked.iter().map(|a| a.0).collect()
-        }
-    }
-
-    /// The display's report flickers off and back, false or unknown: HDR stays on, nothing
-    /// is presented again, and the shader `Frame`, what the settings show as active and the
-    /// nits stay as they were applied, even while the report says nothing of them.
-    #[test]
-    fn a_report_that_flickers_off_and_back_swaps_nothing() {
-        for lost in [Some(false), None] {
-            let mut auto = Auto::new(false);
-            let before = auto.applied;
-            auto.event(0, Some(true), Some(Pq));
-            auto.frames(0, 90);
-            let fresh = auto.applied;
-            assert_eq!(fresh.nits, [300.0, 800.0, 0.0], "a positive report applies");
-            auto.event(100, lost, Some(Pq));
-            auto.frames(100, 390);
-            assert_eq!(auto.applied, fresh, "{lost:?}");
-            assert!(auto.applied.requests_hdr(HdrMode::Auto) && auto.applied.display().hdr);
-            auto.event(400, Some(true), Some(Pq));
-            auto.frames(400, 1500);
-            assert_eq!((auto.applied, auto.since), (fresh, None), "{lost:?}");
-            assert!(auto.presented().is_empty(), "{lost:?}");
-            assert_eq!(auto.applied.frame, before.frame);
-        }
-    }
-
-    /// A loss held through 600 ms turns HDR off once, at 500 ms, and on an event-driven
-    /// display with no event then. The same loss reported again doesn't restart the timer.
-    #[test]
-    fn a_loss_held_turns_hdr_off_once_at_the_deadline() {
-        for lost in [Some(false), None] {
-            let mut auto = Auto::new(false);
-            auto.event(0, lost, Some(Pq));
-            auto.frames(0, 190);
-            auto.event(200, lost, Some(Pq));
-            auto.frames(200, 490);
-            assert_eq!(auto.applied.encoding, Some(Pq), "{lost:?}");
-            auto.frame(500);
-            assert_eq!(auto.applied.encoding, None, "{lost:?}");
-            auto.frames(500, 3000);
-            assert_eq!(auto.presented(), [None], "{lost:?}");
-            assert_eq!(auto.since, None);
-        }
-    }
-
-    /// Where the system is polled, a false read by the poll that starts the timer is read
-    /// again at the deadline, not two seconds after, before it counts: the display came back
-    /// meanwhile, so HDR stays; where it didn't, HDR turns off then. The two-second cadence
-    /// stays otherwise.
-    #[test]
-    fn a_polled_false_is_read_again_at_the_deadline() {
-        for back in [true, false] {
-            let mut auto = Auto::new(true);
-            auto.frames(0, 1990);
-            auto.reports(Some(false), Some(Pq));
-            auto.frame(2000);
-            assert_eq!(
-                (auto.applied.encoding, auto.since.is_some()),
-                (Some(Pq), true)
-            );
-            if back {
-                auto.reports(Some(true), Some(Pq));
-            }
-            auto.frames(2010, 2490);
-            assert_eq!(auto.applied.encoding, Some(Pq), "never before the deadline");
-            auto.frames(2500, 4990);
-            assert_eq!(auto.reads, [0, 2000, 2500, 4500], "back {back}");
-            let after = if back { vec![] } else { vec![None] };
-            assert_eq!(auto.presented(), after, "back {back}");
-        }
-    }
-
-    /// A settings change at the deadline, before the frame's poll (a slider, F11), reads the
-    /// display before the grace ends, and the frame after reads it no more: the display came
-    /// back meanwhile, so HDR stays; where it didn't, HDR turns off then, once.
-    #[test]
-    fn a_settings_change_at_the_deadline_reads_the_display_first() {
-        for back in [true, false] {
-            let mut auto = Auto::new(true);
-            auto.frames(0, 1990);
-            auto.reports(Some(false), Some(Pq));
-            auto.frame(2000);
-            if back {
-                auto.reports(Some(true), Some(Pq));
-            }
-            auto.frames(2010, 2490);
-            auto.update(2500);
-            assert_eq!(auto.applied.hdr_on(), back, "back {back}");
-            auto.frames(2500, 4990);
-            assert_eq!(auto.reads, [0, 2000, 2500, 4500], "back {back}");
-            let after = if back { vec![] } else { vec![None] };
-            assert_eq!(auto.presented(), after, "back {back}");
-        }
-    }
-
-    /// A positive report clears the timer: a later loss has its own 500 ms.
-    #[test]
-    fn a_positive_report_clears_the_timer() {
-        let mut auto = Auto::new(false);
-        auto.event(100, Some(false), Some(Pq));
-        auto.event(300, Some(true), Some(Pq));
-        auto.event(700, Some(false), Some(Pq));
-        auto.frames(700, 1190);
-        assert_eq!(auto.applied.encoding, Some(Pq));
-        auto.frame(1200);
-        assert_eq!(auto.presented(), [None]);
-    }
-
-    /// Off acts at once, and On or Off clear the timer: Auto again starts it anew.
-    #[test]
-    fn off_and_on_take_no_grace() {
-        let mut auto = Auto::new(false);
-        auto.event(100, Some(false), Some(Pq));
-        auto.settings.hdr = HdrMode::Off;
-        auto.update(200);
-        assert_eq!((auto.presented(), auto.since), (vec![None], None));
-        let mut auto = Auto::new(false);
-        auto.event(100, Some(false), Some(Pq));
-        auto.settings.hdr = HdrMode::On;
-        auto.update(200);
-        assert_eq!((auto.applied.encoding, auto.since), (Some(Pq), None));
-        auto.settings.hdr = HdrMode::Auto;
-        auto.update(300);
-        auto.frames(300, 790);
-        assert_eq!(auto.applied.encoding, Some(Pq));
-        auto.frame(800);
-        assert_eq!(auto.presented(), [None]);
-    }
-
-    /// The surface no longer offering the encoding presented ends the grace at once: SDR
-    /// without a report, the other encoding with one.
-    #[test]
-    fn an_encoding_no_longer_offered_is_not_kept() {
-        for offer in [None, Some(ScRgb)] {
-            let mut auto = Auto::new(false);
-            auto.event(100, Some(false), Some(Pq));
-            auto.event(200, Some(false), offer);
-            assert_eq!((auto.presented(), auto.since), (vec![None], None));
-            let mut auto = Auto::new(false);
-            auto.event(100, None, offer);
-            assert_eq!(auto.presented(), [None], "{offer:?}");
-        }
-        let mut auto = Auto::new(false);
-        auto.event(100, Some(false), Some(Pq));
-        auto.event(200, Some(true), Some(ScRgb));
-        assert_eq!(auto.presented(), [Some(ScRgb)]);
-    }
-
-    /// Two windows' timers run apart.
-    #[test]
-    fn two_renderers_keep_their_own_timer() {
-        let (mut a, mut b) = (Auto::new(false), Auto::new(false));
-        b.start = a.start;
-        a.event(100, Some(false), Some(Pq));
-        b.event(300, Some(false), Some(Pq));
-        a.event(400, Some(true), Some(Pq));
-        for ms in (300..=900).step_by(10) {
-            a.frame(ms);
-            b.frame(ms);
-            assert_eq!(b.applied.hdr_on(), ms < 800, "{ms} ms");
-        }
-        assert_eq!((a.presented(), b.presented()), (vec![], vec![None]));
-    }
-}
@@ -597,9 +597,9 @@ const FACE: &str = "    uint hz_q = (uint(gl_VertexIndex) & ~3u) * 6u;\n    \
 /// quad lands whole in one part. The colour's alpha can't decide it, as with `separateAo` it
 /// holds each vertex's own ambient occlusion.
 pub fn terrain_parts(
-    terrain: &horizon_shaders::GbuffersInputs,
+    terrain: &horizon_render_pipeline::GbuffersInputs,
    lava: &[u16],
-) -> [horizon_shaders::GbuffersInputs; 2] {
+) -> [horizon_render_pipeline::GbuffersInputs; 2] {
    let opaque = crate::mesher::OPAQUE_LAYER;
    let lava: String = lava
        .iter()
@@ -619,7 +619,7 @@ pub fn terrain_parts(
 impl PackAtlas {
    /// The vertex inputs of a gbuffers program drawing terrain (`TerrainVertex`, terrain.wgsl's
    /// `vs_terrain` or, for `flat` draws, `vs_terrain_flat`), in atlas coordinates.
-    pub fn terrain_inputs(&self, flat: bool) -> horizon_shaders::GbuffersInputs {
+    pub fn terrain_inputs(&self, flat: bool) -> horizon_render_pipeline::GbuffersInputs {
        let mut declarations = String::from(
            "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in uvec2 hz_v_uv;\n\
             layout(location = 2) in uint hz_v_layer;\nlayout(location = 3) in vec4 hz_v_color;\n\
@@ -753,7 +753,7 @@ impl PackAtlas {
            ("vaColor", "hz_Color"),
            ("vaNormal", "hz_Normal"),
        ];
-        horizon_shaders::GbuffersInputs {
+        horizon_render_pipeline::GbuffersInputs {
            declarations,
            body,
            attributes: attributes
@@ -2,7 +2,7 @@
 //! translator's `DRAW_UNIFORMS`): one slot per render stage of a uniform buffer, picked with a
 //! dynamic offset at each draw.

-use horizon_shaders::{RENDER_STAGES, render_stage};
+use horizon_render_pipeline::{RENDER_STAGES, render_stage};

 /// Where a run of `Frame::entities` begins, and what it is (slice 7): the run lasts until the
 /// next span. Recorded only while a shader pack draws entities, so Horizon's own frames carry
@@ -6,7 +6,7 @@

 use std::ops::Range;

-use horizon_shaders::render_stage;
+use horizon_render_pipeline::render_stage;

 use super::Vertex;
 use super::pack_draw::EntitySpan;
@@ -31,7 +31,7 @@ pub fn buffers() -> [Option<wgpu::VertexBufferLayout<'static>>; 1] {
 /// position, the shared atlas's UV, colour, light (block, sky in 16ths) and the world-oriented
 /// normal. The quad's corners, read from the same vertices at set 1, give the face normal where
 /// the vertex has none (custom geometry) and `at_tangent` along the texture's u, as for terrain.
-pub fn inputs() -> horizon_shaders::GbuffersInputs {
+pub fn inputs() -> horizon_render_pipeline::GbuffersInputs {
    let words = std::mem::size_of::<Vertex>() / 4;
    let mut declarations = "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in vec2 hz_v_uv;\n\
         layout(location = 2) in uint hz_v_overlay;\nlayout(location = 3) in vec4 hz_v_color;\n\
@@ -112,7 +112,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
        // bright.
        ("horizonTier", "float((hz_v_overlay >> 16u) & 255u)"),
    ];
-    horizon_shaders::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations,
        body,
        attributes: attributes
@@ -121,7 +121,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
            .collect(),
        after: String::new(),
        // Cutout, as vanilla's entity types mostly are (OQ-23): the loader's test at 0.1.
-        alpha_test: Some(horizon_shaders::AlphaTest {
+        alpha_test: Some(horizon_render_pipeline::AlphaTest {
            op: ">",
            reference: 0.1,
        }),
@@ -138,7 +138,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
 /// inputs of [`inputs`], each vertex read from set 1 (`hz_entity_vertices`), as `Vertex` lays
 /// it out. The draw's corners walk its quads two triangles each, as `quad_indices` does: corner
 /// `c` of a draw from vertex `first` (a whole quad) is drawn as vertex `first / 4 * 6 + c`.
-pub fn geometry_inputs() -> horizon_shaders::GeometryInputs {
+pub fn geometry_inputs() -> horizon_render_pipeline::GeometryInputs {
    let words = std::mem::size_of::<Vertex>() / 4;
    let pull = format!(
        "        uint hz_pw = hz_vertex_index * {words}u;\n        \
@@ -150,7 +150,7 @@ pub fn geometry_inputs() -> horizon_shaders::GeometryInputs {
         hz_v_light = uvec4(hz_pl & 255u, (hz_pl >> 8u) & 255u, (hz_pl >> 16u) & 255u, hz_pl >> 24u);\n        \
         hz_v_normal = unpackSnorm4x8(hz_entity_vertices[hz_pw + 8u]);\n"
    );
-    horizon_shaders::GeometryInputs {
+    horizon_render_pipeline::GeometryInputs {
        inputs: inputs(),
        pull,
        // Quad `c / 6`, corner 0, 1, 2, 0, 2, 3 of it.
@@ -163,7 +163,7 @@ pub fn geometry_inputs() -> horizon_shaders::GeometryInputs {
 /// What `gbuffers_clouds` reads from the clouds' mesh (entity vertices, `vs_cloud`): the
 /// position moved by the clouds' offset, the colour of the face's shade from their palette,
 /// full light, the face's normal. Set 1 holds the clouds' uniform (`clouds::Uniform`).
-pub fn cloud_inputs() -> horizon_shaders::GbuffersInputs {
+pub fn cloud_inputs() -> horizon_render_pipeline::GbuffersInputs {
    let declarations = "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in vec2 hz_v_uv;\n\
         layout(location = 2) in uint hz_v_overlay;\nlayout(location = 3) in vec4 hz_v_color;\n\
         layout(location = 4) in uvec4 hz_v_light;\nlayout(location = 5) in vec4 hz_v_normal;\n\
@@ -183,7 +183,7 @@ pub fn cloud_inputs() -> horizon_shaders::GbuffersInputs {
        ("vaColor", "hz_Color"),
        ("vaNormal", "hz_Normal"),
    ];
-    horizon_shaders::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations,
        body,
        attributes: attributes
@@ -17,7 +17,7 @@ const UNIFORM: u64 = 2 * 64;
 const SLOT: u64 = 32;

 /// What `gbuffers_hand` reads: the entity inputs, and the hand's projection from set 1.
-pub fn inputs() -> horizon_shaders::GbuffersInputs {
+pub fn inputs() -> horizon_render_pipeline::GbuffersInputs {
    let mut inputs = super::pack_entities::inputs();
    // No last frame's hand to measure from: the hand's `at_velocity` reads zero (and its set 1
    // has no previous vertices).
@@ -270,7 +270,7 @@ fn translucent_quad(quad: &[Vertex]) -> bool {
 /// outside block entities, and `currentRenderedItemId`.
 fn draw_slot(id: i32, translucent: bool) -> [u8; SLOT as usize] {
    let mut bytes = [0u8; SLOT as usize];
-    let stage = horizon_shaders::render_stage(if translucent {
+    let stage = horizon_render_pipeline::render_stage(if translucent {
        "HAND_TRANSLUCENT"
    } else {
        "HAND_SOLID"
@@ -4,7 +4,8 @@

 use std::collections::BTreeMap;

-use horizon_shaders::{BufferObject, CustomImage, Format, Kind};
+use horizon_render_pipeline::{Format, Kind};
+use horizon_shaders::{BufferObject, CustomImage};

 pub(super) struct PackImage {
    pub(super) def: CustomImage,
@@ -8,7 +8,7 @@
 /// width in pixels. The strip's corners 0 and 1 are at the start, 2 and 3 at the end (six
 /// vertices per edge: pack pipelines draw triangle lists); the
 /// width is applied in screen space after the pack's transform.
-pub fn inputs() -> horizon_shaders::GbuffersInputs {
+pub fn inputs() -> horizon_render_pipeline::GbuffersInputs {
    let declarations =
        "layout(location = 0) in vec3 hz_l_start;\nlayout(location = 1) in vec3 hz_l_end;\n\
         layout(location = 2) in vec4 hz_l_argb;\nlayout(location = 3) in float hz_l_width;\n\
@@ -41,7 +41,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
         if ((hz_l_c & 1) != 0) hz_l_o = -hz_l_o;\n        \
         gl_Position.xy += hz_l_o * gl_Position.w;\n    }\n"
        .to_owned();
-    horizon_shaders::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations,
        body,
        attributes: attributes
@@ -18,7 +18,8 @@
 use std::collections::HashMap;

 use glam::{DMat4, DVec3};
-use horizon_shaders::{BUFFERS, Format, Group, Kind, Post, SHADOW_COLORS};
+use horizon_render_pipeline::{BUFFERS, Format, Kind, SHADOW_COLORS};
+use horizon_shaders::{Group, Post};
 use smallvec::SmallVec;

 use super::pack_draw::DrawUniforms;
@@ -54,10 +55,6 @@ mod sky_disc_blend_tests;
 #[cfg(test)]
 mod undrawn_terrain_tests;

-mod image_formats;
-use image_formats::{image_format, storage_formats_of};
-#[cfg(test)]
-mod full_outputs_tests;
 #[cfg(test)]
 mod shadow_faces_tests;

@@ -128,7 +125,7 @@ enum Source {
    ShadowDepth(usize, bool),
    /// `shadowcolor0/1` read outside the shadow programs (in them they are `Color`).
    ShadowColor(usize),
-    /// The boats' water patches' depth (`horizon_shaders::WATER_MASK`), for translucent terrain.
+    /// The boats' water patches' depth (`horizon_render_pipeline::WATER_MASK`), for translucent terrain.
    WaterMask,
 }

@@ -886,13 +883,13 @@ fn fits(ty: &str, sample_type: wgpu::TextureSampleType) -> bool {
 /// `hz_depth_linear` for a program: 1 for each of shadowtex0, shadowtex1, `shadow` and
 /// `watershadow` whose depth filters (`linear`, bit n: shadowtex n). `shadow` is shadowtex1 in a
 /// program that also declares `watershadow` (6.3).
-fn depth_linear(interface: &horizon_shaders::Interface, linear: u8) -> [f32; 4] {
+fn depth_linear(interface: &horizon_render_pipeline::Interface, linear: u8) -> [f32; 4] {
    let watershadow = interface.samplers.iter().any(|s| s.name == "watershadow");
    [0, 1, usize::from(watershadow), 0].map(|n| f32::from(linear >> n & 1))
 }

 fn source(name: &str, shadow_space: bool, shadow_pass: bool, watershadow: bool) -> Source {
-    let shadow_color = horizon_shaders::shadow_color(name);
+    let shadow_color = horizon_render_pipeline::shadow_color(name);
    let shadow_depth = match name {
        "shadowtex0" | "watershadow" | "shadowtex0HW" => Some(0),
        "shadowtex1" | "shadowtex1HW" => Some(1),
@@ -911,7 +908,7 @@ fn source(name: &str, shadow_space: bool, shadow_pass: bool, watershadow: bool)
            };
        }
    }
-    if shadow_space && horizon_shaders::buffer_index(name).is_some() {
+    if shadow_space && horizon_render_pipeline::buffer_index(name).is_some() {
        // colortex buffers are not this pass's.
        return Source::Dummy;
    }
@@ -924,8 +921,8 @@ fn source(name: &str, shadow_space: bool, shadow_pass: bool, watershadow: bool)
        "lightmap" => Source::Lightmap,
        "normals" => Source::Normals,
        "specular" => Source::Specular,
-        horizon_shaders::WATER_MASK => Source::WaterMask,
-        n => horizon_shaders::buffer_index(n).map_or(Source::Dummy, Source::Color),
+        horizon_render_pipeline::WATER_MASK => Source::WaterMask,
+        n => horizon_render_pipeline::buffer_index(n).map_or(Source::Dummy, Source::Color),
    }
 }

@@ -1506,7 +1503,7 @@ fn owned_buffers(
 #[allow(clippy::too_many_arguments, clippy::type_complexity)]
 fn bindings(
    features: wgpu::Features,
-    interface: &horizon_shaders::Interface,
+    interface: &horizon_render_pipeline::Interface,
    name: &str,
    group: Group,
    buffers: &[u32],
@@ -1577,12 +1574,12 @@ fn bindings(
            // pack of ours (#9064) bound it over `gaux2` and `noisetex` but not over names of its
            // own, where a raw texture was bound; this rule is a fit to those cases.
            let unbound = t.png
-                && t.stage != horizon_shaders::EVERY_STAGE
+                && t.stage != horizon_render_pipeline::textures::EVERY_STAGE
                && source(&s.name, false, true, false) == Source::Dummy;
            !unbound
                && (t.stage != pack_textures::stage(group)
                    || released.0 != t.stage
-                    || horizon_shaders::buffer_index(&t.name)
+                    || horizon_render_pipeline::buffer_index(&t.name)
                        .is_none_or(|b| released.1 & 1 << b == 0))
        });
        let image = pack
@@ -1829,6 +1826,98 @@ fn bindings(
    Some((entries, samplers, slots, reads, shadow_reads, images))
 }

+/// Makes each storage image of `module` in group 0 declare the format its layout entry binds:
+/// a `layout(r11f_g11f_b10f)` image whose texture is the `RGBA16F` stand-in (`bindings`).
+fn storage_formats_of(module: &mut naga::Module, entries: &[wgpu::BindGroupLayoutEntry]) {
+    let globals: Vec<_> = module.global_variables.iter().map(|(h, _)| h).collect();
+    for handle in globals {
+        let var = &module.global_variables[handle];
+        let Some(naga::ResourceBinding { group: 0, binding }) = var.binding else {
+            continue;
+        };
+        let naga::TypeInner::Image {
+            dim,
+            arrayed,
+            class: naga::ImageClass::Storage { format, access },
+        } = module.types[var.ty].inner
+        else {
+            continue;
+        };
+        let bound = entries.iter().find_map(|e| match e.ty {
+            wgpu::BindingType::StorageTexture { format, .. } if e.binding == binding => {
+                Some(format)
+            }
+            _ => None,
+        });
+        if format == naga::StorageFormat::Rg11b10Ufloat
+            && bound == Some(wgpu::TextureFormat::Rgba16Float)
+        {
+            let ty = module.types.insert(
+                naga::Type {
+                    name: module.types[var.ty].name.clone(),
+                    inner: naga::TypeInner::Image {
+                        dim,
+                        arrayed,
+                        class: naga::ImageClass::Storage {
+                            format: naga::StorageFormat::Rgba16Float,
+                            access,
+                        },
+                    },
+                },
+                naga::Span::UNDEFINED,
+            );
+            module.global_variables[handle].ty = ty;
+        }
+    }
+}
+
+/// The wgpu format of an image's format qualifier.
+fn image_format(qualifier: &str) -> Option<wgpu::TextureFormat> {
+    use wgpu::TextureFormat as T;
+    Some(match qualifier {
+        "rgba32f" => T::Rgba32Float,
+        "rgba16f" => T::Rgba16Float,
+        "rg32f" => T::Rg32Float,
+        "rg16f" => T::Rg16Float,
+        "r11f_g11f_b10f" => T::Rg11b10Ufloat,
+        "r32f" => T::R32Float,
+        "r16f" => T::R16Float,
+        "rgba16" => T::Rgba16Unorm,
+        "rgb10_a2" => T::Rgb10a2Unorm,
+        "rgba8" => T::Rgba8Unorm,
+        "rg16" => T::Rg16Unorm,
+        "rg8" => T::Rg8Unorm,
+        "r16" => T::R16Unorm,
+        "r8" => T::R8Unorm,
+        "rgba16_snorm" => T::Rgba16Snorm,
+        "rgba8_snorm" => T::Rgba8Snorm,
+        "rg16_snorm" => T::Rg16Snorm,
+        "rg8_snorm" => T::Rg8Snorm,
+        "r16_snorm" => T::R16Snorm,
+        "r8_snorm" => T::R8Snorm,
+        "rgba32i" => T::Rgba32Sint,
+        "rgba16i" => T::Rgba16Sint,
+        "rgba8i" => T::Rgba8Sint,
+        "rg32i" => T::Rg32Sint,
+        "rg16i" => T::Rg16Sint,
+        "rg8i" => T::Rg8Sint,
+        "r32i" => T::R32Sint,
+        "r16i" => T::R16Sint,
+        "r8i" => T::R8Sint,
+        "rgba32ui" => T::Rgba32Uint,
+        "rgba16ui" => T::Rgba16Uint,
+        "rgb10_a2ui" => T::Rgb10a2Uint,
+        "rgba8ui" => T::Rgba8Uint,
+        "rg32ui" => T::Rg32Uint,
+        "rg16ui" => T::Rg16Uint,
+        "rg8ui" => T::Rg8Uint,
+        "r32ui" => T::R32Uint,
+        "r16ui" => T::R16Uint,
+        "r8ui" => T::R8Uint,
+        _ => return None,
+    })
+}
+
 /// The value slot of the pack's custom uniform `name` for a program declaring it as GLSL type
 /// `ty`: after the frame's uniforms, in the order of `custom` (each with the type
 /// `shaders.properties` gives it). A `float`, `int`, `vec2`, `vec3` or `vec4` custom uniform
@@ -2194,7 +2283,7 @@ fn build_compute(
    device: &wgpu::Device,
    name: String,
    group: Group,
-    c: horizon_shaders::ComputeProgram,
+    c: horizon_render_pipeline::ComputeProgram,
    formats: &[wgpu::TextureFormat; BUFFERS],
    shadow: Option<&[wgpu::TextureFormat; SHADOW_COLORS]>,
    notes: &mut Vec<String>,
@@ -2432,7 +2521,7 @@ impl PackPost {
        let shadow_config = post.config.shadow.clone();
        let noise_size = post.config.noise_resolution.unwrap_or(256);
        let half_lives = post.config.half_lives;
-        for (name, ticks) in horizon_shaders::HALF_LIVES.iter().zip(half_lives) {
+        for (name, ticks) in horizon_render_pipeline::HALF_LIVES.iter().zip(half_lives) {
            if let Some(t) = ticks {
                notes.push(format!("`{name}` is {t} ticks"));
            }
@@ -2716,21 +2805,10 @@ impl PackPost {
            .shadow
            .zip(shadow_geometry.as_ref())
            .and_then(|(p, g)| build(p, Some(g)));
-        // A GPU that refuses translucent terrain's program with the boats' water patches gets it
-        // without them (`Post::shadow_water_plain`), rather than no translucent shadows at all.
-        let mut plain = post.shadow_water_plain;
        let shadow_water = post
            .shadow_water
            .zip(shadow_geometry.as_ref())
            .and_then(|(p, g)| build(p, Some(g)));
-        let unpatched = shadow_water.is_none().then(|| plain.take()).flatten();
-        let unpatched_name = unpatched.as_ref().map(|p| p.name.clone());
-        let shadow_water = shadow_water.or_else(|| {
-            unpatched
-                .zip(shadow_geometry.as_ref())
-                .and_then(|(p, g)| build(p, Some(g)))
-        });
-        let water_unpatched = unpatched_name.filter(|_| shadow_water.is_some());
        let (hides_sky, hides_celestial) = (post.sky.is_some(), post.sky_textured.is_some());
        let sky = (post.sky.is_some() || post.sky_textured.is_some()).then(|| {
            let geometry = PackSky::new(device);
@@ -3287,17 +3365,6 @@ impl PackPost {
        let white = [255u8; 4];
        let black = [0u8; 4];
        let flat_normal = [128u8, 128, 255, 255];
-        // Said as what it is, not as a program skipped.
-        if let Some(name) = water_unpatched {
-            let skipped = format!("{name}: skipped: ");
-            if let Some(n) = notes.iter_mut().rev().find(|n| n.starts_with(&skipped)) {
-                *n = format!(
-                    "{name}: translucent terrain without the boats' water patches, as the GPU \
-                     refused it with them ({})",
-                    &n[skipped.len()..]
-                );
-            }
-        }
        let jobs = (pack.jobs.as_ref())
            .map(std::cell::RefCell::take)
            .unwrap_or_default();
@@ -5998,7 +6065,7 @@ mod tests {
            texture("composite", "tr", false),
            texture("composite", "gaux2", true),
            texture("composite", "noisetex", true),
-            texture(horizon_shaders::EVERY_STAGE, "cp", true),
+            texture(horizon_render_pipeline::textures::EVERY_STAGE, "cp", true),
        ];
        let names = ["tp", "tr", "gaux2", "noisetex", "cp"];
        let interface = horizon_shaders::Interface {
@@ -1,109 +0,0 @@
-//! A shadow program writing as many vertex outputs as the GPU takes leaves no room for the boats'
-//! water patches (`GbuffersInputs::water_patches`, one output more): translucent terrain gets
-//! the program without them, not no shadow program. The programs here are original.
-use super::destination_tests::Fixture;
-use super::*;
-use std::io::{Cursor, Write};
-
-fn pack(outputs: u32) -> Post {
-    let mut zip = zip::ZipWriter::new(Cursor::new(Vec::new()));
-    let mut add = |name: &str, source: &str| {
-        zip.start_file(
-            format!("shaders/{name}"),
-            zip::write::SimpleFileOptions::default(),
-        )
-        .unwrap();
-        zip.write_all(source.as_bytes()).unwrap();
-    };
-    let declared: String = (0..outputs)
-        .map(|i| format!("varying vec4 v{i};\n"))
-        .collect();
-    let written: String = (0..outputs).map(|i| format!("v{i}=vec4({i}.0);")).collect();
-    let read: String = (0..outputs).map(|i| format!("+v{i}")).collect();
-    add(
-        "shadow.vsh",
-        &format!(
-            "#version 120\n{declared}void main() {{ gl_Position=vec4(gl_Vertex.xy,0.5,1.0); {written} }}\n"
-        ),
-    );
-    add(
-        "shadow.fsh",
-        &format!("#version 120\n{declared}void main() {{ gl_FragData[0]=vec4(0.0){read}; }}\n"),
-    );
-    add(
-        "final.vsh",
-        "#version 120\nvarying vec2 uv;\nvoid main() { uv=gl_MultiTexCoord0.xy; gl_Position=ftransform(); }\n",
-    );
-    add(
-        "final.fsh",
-        "#version 120\nconst int shadowMapResolution=16;\nuniform sampler2D shadowcolor0;\n\
-         varying vec2 uv;\nvoid main() { gl_FragColor=texture2D(shadowcolor0,uv); }\n",
-    );
-    let pack = horizon_shaders::Pack::from_zip_bytes(
-        "original-full-outputs",
-        zip.finish().unwrap().into_inner(),
-    )
-    .unwrap();
-    let mut macros = horizon_shaders::Macros::standard();
-    let (properties, _) = horizon_shaders::read_properties(&pack, &mut macros);
-    let inputs = horizon_shaders::GameInputs {
-        terrain: Some(horizon_shaders::GbuffersInputs {
-            item_id_declared: false,
-            far_depth: false,
-            paged_maps: false,
-            water_mask: false,
-            water_patches: false,
-            declarations: "layout(location=0)in vec3 fixture_position;\n".into(),
-            body: "hz_Vertex=vec4(fixture_position,1.0);hz_Color=vec4(1.0);\
-                   hz_MultiTexCoord0=vec4(0.0);hz_MultiTexCoord1=vec4(240.0);\
-                   hz_MultiTexCoord2=vec4(240.0);hz_Normal=vec3(0.0,0.0,1.0);\n"
-                .into(),
-            attributes: vec![],
-            after: String::new(),
-            alpha_test: None,
-        }),
-        ..Default::default()
-    };
-    horizon_shaders::load_post(&pack, "", &properties, &macros, &inputs)
-}
-
-#[test]
-fn a_shadow_program_with_every_output_drops_the_boats_patches_not_its_water() {
-    let Some(gpu) = Fixture::new() else { return };
-    const ATTRS: [wgpu::VertexAttribute; 1] = wgpu::vertex_attr_array![0=>Float32x3];
-    let layouts = [Some(wgpu::VertexBufferLayout {
-        array_stride: 12,
-        step_mode: wgpu::VertexStepMode::Vertex,
-        attributes: &ATTRS,
-    })];
-    let geometry = || {
-        Some(Geometry {
-            material_maps: false,
-            buffers: &layouts,
-            table: None,
-            depth_write: true,
-            atlas: None,
-            ids: None,
-            cull: true,
-        })
-    };
-    let outputs = gpu.device.limits().max_inter_stage_shader_variables;
-    let post = gpu.build_with_terrain(pack(outputs), geometry());
-    assert!(post.has_shadow(), "{:?}", post.notes);
-    assert!(post.shadow_water.is_some(), "{:?}", post.notes);
-    assert!(
-        post.notes
-            .iter()
-            .any(|n| n.contains("without the boats' water patches")),
-        "{:?}",
-        post.notes
-    );
-    // With room for them, the patches stay and nothing is said.
-    let post = gpu.build_with_terrain(pack(outputs - 1), geometry());
-    assert!(post.shadow_water.is_some(), "{:?}", post.notes);
-    assert!(
-        !post.notes.iter().any(|n| n.contains("water patches")),
-        "{:?}",
-        post.notes
-    );
-}
@@ -1,97 +0,0 @@
-//! Image formats: a storage image's format qualifier as wgpu's, and the stand-in a module's
-//! storage images declare.
-
-/// Makes each storage image of `module` in group 0 declare the format its layout entry binds:
-/// a `layout(r11f_g11f_b10f)` image whose texture is the `RGBA16F` stand-in (`bindings`).
-pub(super) fn storage_formats_of(
-    module: &mut naga::Module,
-    entries: &[wgpu::BindGroupLayoutEntry],
-) {
-    let globals: Vec<_> = module.global_variables.iter().map(|(h, _)| h).collect();
-    for handle in globals {
-        let var = &module.global_variables[handle];
-        let Some(naga::ResourceBinding { group: 0, binding }) = var.binding else {
-            continue;
-        };
-        let naga::TypeInner::Image {
-            dim,
-            arrayed,
-            class: naga::ImageClass::Storage { format, access },
-        } = module.types[var.ty].inner
-        else {
-            continue;
-        };
-        let bound = entries.iter().find_map(|e| match e.ty {
-            wgpu::BindingType::StorageTexture { format, .. } if e.binding == binding => {
-                Some(format)
-            }
-            _ => None,
-        });
-        if format == naga::StorageFormat::Rg11b10Ufloat
-            && bound == Some(wgpu::TextureFormat::Rgba16Float)
-        {
-            let ty = module.types.insert(
-                naga::Type {
-                    name: module.types[var.ty].name.clone(),
-                    inner: naga::TypeInner::Image {
-                        dim,
-                        arrayed,
-                        class: naga::ImageClass::Storage {
-                            format: naga::StorageFormat::Rgba16Float,
-                            access,
-                        },
-                    },
-                },
-                naga::Span::UNDEFINED,
-            );
-            module.global_variables[handle].ty = ty;
-        }
-    }
-}
-
-/// The wgpu format of an image's format qualifier.
-pub(super) fn image_format(qualifier: &str) -> Option<wgpu::TextureFormat> {
-    use wgpu::TextureFormat as T;
-    Some(match qualifier {
-        "rgba32f" => T::Rgba32Float,
-        "rgba16f" => T::Rgba16Float,
-        "rg32f" => T::Rg32Float,
-        "rg16f" => T::Rg16Float,
-        "r11f_g11f_b10f" => T::Rg11b10Ufloat,
-        "r32f" => T::R32Float,
-        "r16f" => T::R16Float,
-        "rgba16" => T::Rgba16Unorm,
-        "rgb10_a2" => T::Rgb10a2Unorm,
-        "rgba8" => T::Rgba8Unorm,
-        "rg16" => T::Rg16Unorm,
-        "rg8" => T::Rg8Unorm,
-        "r16" => T::R16Unorm,
-        "r8" => T::R8Unorm,
-        "rgba16_snorm" => T::Rgba16Snorm,
-        "rgba8_snorm" => T::Rgba8Snorm,
-        "rg16_snorm" => T::Rg16Snorm,
-        "rg8_snorm" => T::Rg8Snorm,
-        "r16_snorm" => T::R16Snorm,
-        "r8_snorm" => T::R8Snorm,
-        "rgba32i" => T::Rgba32Sint,
-        "rgba16i" => T::Rgba16Sint,
-        "rgba8i" => T::Rgba8Sint,
-        "rg32i" => T::Rg32Sint,
-        "rg16i" => T::Rg16Sint,
-        "rg8i" => T::Rg8Sint,
-        "r32i" => T::R32Sint,
-        "r16i" => T::R16Sint,
-        "r8i" => T::R8Sint,
-        "rgba32ui" => T::Rgba32Uint,
-        "rgba16ui" => T::Rgba16Uint,
-        "rgb10_a2ui" => T::Rgb10a2Uint,
-        "rgba8ui" => T::Rgba8Uint,
-        "rg32ui" => T::Rg32Uint,
-        "rg16ui" => T::Rg16Uint,
-        "rg8ui" => T::Rg8Uint,
-        "r32ui" => T::R32Uint,
-        "r16ui" => T::R16Uint,
-        "r8ui" => T::R8Uint,
-        _ => return None,
-    })
-}
@@ -10,7 +10,7 @@
 //! a fit to one driver's values, not a rule Iris states. `RGBA4` and `RGBA2` read back the `RGBA8`
 //! bytes in the same probe, as Horizon's 8-bit buffers already do.

-use horizon_shaders::{Format, Kind};
+use horizon_render_pipeline::{Format, Kind};
 use naga::{BinaryOperator, Expression, Literal, MathFunction, Statement, VectorSize};

 /// The bits each channel keeps in a buffer of format `f`, for the formats that keep fewer than
@@ -3,7 +3,7 @@
 //! with two sides that `shadowcomp` programs flip as composite programs flip colortex (6.1.6).
 //! Square, `shadowMapResolution` pixels.

-use horizon_shaders::SHADOW_COLORS;
+use horizon_render_pipeline::SHADOW_COLORS;

 type Ops<T> = wgpu::Operations<T>;
 type Color = wgpu::Color;
@@ -97,7 +97,11 @@ pub(super) fn stand_in(device: &wgpu::Device) -> wgpu::TextureView {
 }

 impl ShadowTargets {
-    pub fn reset_history(&mut self, device: &wgpu::Device, shadow: &horizon_shaders::Shadow) {
+    pub fn reset_history(
+        &mut self,
+        device: &wgpu::Device,
+        shadow: &horizon_render_pipeline::Shadow,
+    ) {
        let mut colors = 0;
        let mut doubled = 0;
        let formats = std::array::from_fn(|n| match &self.color[n] {
@@ -125,7 +129,7 @@ impl ShadowTargets {
    /// resolution is kept within the device's limit.
    pub fn new(
        device: &wgpu::Device,
-        shadow: &horizon_shaders::Shadow,
+        shadow: &horizon_render_pipeline::Shadow,
        formats: [wgpu::TextureFormat; SHADOW_COLORS],
        colors: u16,
        doubled: u16,
@@ -58,7 +58,7 @@ pub(super) const ATTRIBUTES: [wgpu::VertexAttribute; 2] =
    wgpu::vertex_attr_array![0 => Float32x3, 1 => Uint32];

 /// What `gbuffers_skybasic` reads from these vertices.
-pub fn inputs() -> horizon_shaders::GbuffersInputs {
+pub fn inputs() -> horizon_render_pipeline::GbuffersInputs {
    let declarations =
        "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in uint hz_v_kind;\n\
         layout(set = 1, binding = 0) uniform HzSky { mat4 hz_sky_stars; vec4 hz_sky_color; \
@@ -90,7 +90,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
         hz_MultiTexCoord2 = hz_MultiTexCoord1;\n    \
         hz_Normal = vec3(0.0, 0.0, 1.0);\n"
    );
-    horizon_shaders::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations,
        body,
        attributes: vec![
@@ -111,8 +111,8 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
 }

 /// What `gbuffers_skytextured` reads from the sun and moon's vertices.
-pub fn celestial_inputs() -> horizon_shaders::GbuffersInputs {
-    horizon_shaders::GbuffersInputs {
+pub fn celestial_inputs() -> horizon_render_pipeline::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations:
            "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in vec2 hz_v_uv;\n\
             layout(location = 2) in vec4 hz_v_color;\n"
@@ -1,7 +1,11 @@
 //! A shader pack's custom textures (`texture.<stage>.<name>`, `texture.noise`) on the GPU, and
 //! which of them a program's sampler reads.

-use horizon_shaders::{CustomTexture, Group, Kind, Texels, Texture, TextureDim, TextureSource};
+use horizon_render_pipeline::Kind;
+use horizon_render_pipeline::textures::{
+    CustomTexture, Dim as TextureDim, EVERY_STAGE, Texels, Texture, TextureSource,
+};
+use horizon_shaders::Group;

 /// What a custom texture is once uploaded: an image of ours, or one the game already has.
 pub(super) enum Image {
@@ -118,24 +122,24 @@ pub(super) fn find(textures: &[PackTexture], group: Group, ty: &str, name: &str)
    } else {
        wgpu::TextureViewDimension::D2
    };
-    let buffer = horizon_shaders::buffer_index(name);
+    let buffer = horizon_render_pipeline::buffer_index(name);
    let staged = textures.iter().position(|t| {
        t.stage == stage(group)
            && t.dimension == dimension
            && (t.name == name
-                || buffer.is_some() && horizon_shaders::buffer_index(&t.name) == buffer)
+                || buffer.is_some() && horizon_render_pipeline::buffer_index(&t.name) == buffer)
    });
    staged.or_else(|| {
-        textures.iter().position(|t| {
-            t.stage == horizon_shaders::EVERY_STAGE && t.dimension == dimension && t.name == name
-        })
+        textures
+            .iter()
+            .position(|t| t.stage == EVERY_STAGE && t.dimension == dimension && t.name == name)
    })
 }

 /// The `shaders.properties` key a texture came from, for notes.
 fn key(stage: &str, name: &str) -> String {
    match stage {
-        horizon_shaders::EVERY_STAGE => format!("customTexture.{name}"),
+        EVERY_STAGE => format!("customTexture.{name}"),
        _ => format!("texture.{stage}.{name}"),
    }
 }
@@ -350,7 +354,7 @@ mod tests {
    #[test]
    fn custom_textures_reach_every_program() {
        use wgpu::TextureViewDimension as D;
-        let every = horizon_shaders::EVERY_STAGE;
+        let every = EVERY_STAGE;
        let textures = [
            lightmap(every, "texClouds", D::D3),
            lightmap("composite", "texClouds", D::D3),
@@ -28,7 +28,7 @@
 //! [-w, w], and the depth buffers packs read hold GL window depth.

 use glam::{DMat4, DVec3, Mat4, Vec3, Vec4};
-use horizon_shaders::Shadow;
+use horizon_render_pipeline::Shadow;

 use super::Frame;

@@ -440,7 +440,7 @@ pub struct FrameUniforms {
    center_depth: Option<f32>,
    /// The pack's shadow settings (7.1).
    pub shadow: Shadow,
-    /// The pack's smoothing half-lives in ticks (`horizon_shaders::HALF_LIVES`).
+    /// The pack's smoothing half-lives in ticks (`horizon_render_pipeline::HALF_LIVES`).
    pub half_lives: [Option<f32>; 4],
 }

@@ -2717,7 +2717,7 @@ pub(super) mod initial_history_tests {
 /// `horizonWaterPatch<k>`'s `k`: patch `k / 2`, its corner and y range (even) or edges (odd).
 fn water_patch_index(name: &str) -> Option<usize> {
    let k: usize = name.strip_prefix("horizonWaterPatch")?.parse().ok()?;
-    (k < 2 * horizon_shaders::WATER_PATCHES).then_some(k)
+    (k < 2 * horizon_render_pipeline::WATER_PATCHES).then_some(k)
 }

 /// The boats' water patches among the frame's entity quads (`WATER_MASK_OVERLAY`), the first
@@ -2729,7 +2729,7 @@ pub(super) fn water_patches(entities: &[super::Vertex]) -> Vec<[[f32; 4]; 2]> {
    let mut points: Vec<[f32; 3]> = Vec::new();
    let flush = |points: &mut Vec<[f32; 3]>, out: &mut Vec<[[f32; 4]; 2]>| {
        if let Some(b) = patch_box(points)
-            && out.len() < horizon_shaders::WATER_PATCHES
+            && out.len() < horizon_render_pipeline::WATER_PATCHES
        {
            out.push(b);
        }
@@ -11,7 +11,7 @@ use super::pack_post::Weather;
 /// What `gbuffers_weather` reads from a weather vertex: camera-relative position, the UV in
 /// repeats of the sprite, colour (with vanilla's fade) and light. Weather has no normal; the
 /// pack sees straight up.
-pub fn inputs() -> horizon_shaders::GbuffersInputs {
+pub fn inputs() -> horizon_render_pipeline::GbuffersInputs {
    let declarations =
        "layout(location = 0) in vec3 hz_v_pos;\nlayout(location = 1) in vec2 hz_v_uv;\n\
         layout(location = 2) in uint hz_v_overlay;\nlayout(location = 3) in vec4 hz_v_color;\n\
@@ -31,7 +31,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
        ("vaColor", "hz_Color"),
        ("vaNormal", "hz_Normal"),
    ];
-    horizon_shaders::GbuffersInputs {
+    horizon_render_pipeline::GbuffersInputs {
        declarations,
        body,
        attributes: attributes
@@ -40,7 +40,7 @@ pub fn inputs() -> horizon_shaders::GbuffersInputs {
            .collect(),
        after: String::new(),
        // Vanilla's weather drops texels below 0.1, as Horizon's own weather shader does.
-        alpha_test: Some(horizon_shaders::AlphaTest {
+        alpha_test: Some(horizon_render_pipeline::AlphaTest {
            op: ">",
            reference: 0.1,
        }),
@@ -158,7 +158,7 @@ impl Weather {
        match native {
            Some((pipeline, frame)) => {
                pass.set_pipeline(pipeline);
-                pass.set_bind_group(horizon_shader_api::stages::GROUP, frame, &[]);
+                pass.set_bind_group(horizon_render_pipeline::stages::GROUP, frame, &[]);
            }
            None => pass.set_pipeline(&self.pipeline),
        }
@@ -225,7 +225,7 @@ struct HorizonWeatherOut {
 ";

 /// The shader of a native pack's weather stage `source`.
-fn native_source(source: &str, api: horizon_shader_api::Api) -> String {
+fn native_source(source: &str, api: horizon_render_pipeline::Api) -> String {
    format!(
        "{source}\n// Horizon's weather (entity.wgsl)\n{}{}{NATIVE_ENTRIES}",
        super::wgsl_prefix::prefixed(&super::entity_shader(), "horizon_entity_"),
@@ -245,7 +245,7 @@ pub(super) fn native_pipeline(
    stage: &horizon_shader_api::check::CheckedStage,
    constants: &[(String, f64)],
 ) -> Result<wgpu::RenderPipeline, String> {
-    use horizon_shader_api::stages::GROUP;
+    use horizon_render_pipeline::stages::GROUP;
    let text = native_source(&stage.source, frame.api);
    let module = naga::front::wgsl::parse_str(&text)
        .map_err(|e| format!("{}: {}", stage.file, e.emit_to_string(&text)))?;
@@ -322,7 +322,7 @@ mod tests {

    #[test]
    fn a_native_weather_stage_validates() {
-        use horizon_shader_api::{Api, stages::StageKind};
+        use horizon_render_pipeline::{Api, StageKind};
        for api in [Api::V0_1, Api::V0_2] {
            let source = StageKind::Weather.prelude(api)
                + "fn weather(input: WeatherInput) -> vec4<f32> {\n    \
@@ -50,98 +50,6 @@ struct TaaResources {
    uniform: wgpu::Buffer,
 }

-/// One frame handed to an upscaler backend: the jittered world at `render_size` and what
-/// it needs to rebuild it at `output_size`. The motion is the camera's alone (`reproject`);
-/// objects that move on their own carry no motion vectors yet.
-// Only TAA reads it so far; a vendor backend reads the rest (#12918).
-#[allow(dead_code)]
-pub(super) struct UpscaleFrame<'a> {
-    /// The world's colour, rendered with this frame's jitter.
-    pub color: &'a wgpu::TextureView,
-    /// The world's depth, at `render_size`.
-    pub depth: &'a wgpu::TextureView,
-    pub render_size: [u32; 2],
-    pub output_size: [u32; 2],
-    /// The jitter in clip space, as added to the projection.
-    pub jitter_clip: [f32; 2],
-    /// The same jitter in rendered pixels, y down.
-    pub jitter_pixels: [f32; 2],
-    /// This frame's unjittered clip space to the previous frame's.
-    pub reproject: [[f32; 4]; 4],
-    /// The history is unusable: a cut, a resize, a frame without the upscaler.
-    pub reset: bool,
-    /// Frames jittered so far.
-    pub index: u32,
-}
-
-/// Something that turns the jittered low-resolution world into the output picture.
-/// TAA (`TaaResources`) is the only backend; `Target` is the per-size state a backend
-/// keeps beside the world target (TAA's history textures).
-pub(super) trait UpscalerBackend {
-    type Target;
-    /// The name its GPU timing is shown under.
-    fn name(&self) -> &'static str;
-    /// Write this frame's output and return the bind group that shows it (`draw_onto`).
-    fn resolve<'t>(
-        &self,
-        queue: &wgpu::Queue,
-        encoder: &mut wgpu::CommandEncoder,
-        frame: &UpscaleFrame<'_>,
-        target: &'t Self::Target,
-        timing: Option<&mut super::pack_timing::PassTiming>,
-    ) -> &'t wgpu::BindGroup;
-}
-
-impl UpscalerBackend for TaaResources {
-    type Target = History;
-
-    fn name(&self) -> &'static str {
-        "TAA"
-    }
-
-    fn resolve<'t>(
-        &self,
-        queue: &wgpu::Queue,
-        encoder: &mut wgpu::CommandEncoder,
-        frame: &UpscaleFrame<'_>,
-        taa: &'t History,
-        timing: Option<&mut super::pack_timing::PassTiming>,
-    ) -> &'t wgpu::BindGroup {
-        // The resolve bind group already samples `frame.color` and `frame.depth`.
-        let i = (frame.index % 2) as usize;
-        let uniform = TaaUniform {
-            reproject: frame.reproject,
-            jitter: [
-                frame.jitter_clip[0],
-                frame.jitter_clip[1],
-                if frame.reset { 1.0 } else { 0.0 },
-                0.0,
-            ],
-        };
-        queue.write_buffer(&self.uniform, 0, bytemuck::bytes_of(&uniform));
-        let attachments = [Some(wgpu::RenderPassColorAttachment {
-            view: &taa.history[i],
-            resolve_target: None,
-            depth_slice: None,
-            ops: wgpu::Operations {
-                load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
-                store: wgpu::StoreOp::Store,
-            },
-        })];
-        let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
-            label: Some("Horizon TAA"),
-            timestamp_writes: timing.and_then(|t| t.writes(self.name())),
-            color_attachments: &attachments,
-            ..Default::default()
-        });
-        pass.set_pipeline(&self.pipeline);
-        pass.set_bind_group(0, &taa.resolve[i], &[]);
-        pass.draw(0..3, 0..1);
-        drop(pass);
-        &taa.show[i]
-    }
-}
-
 pub struct Post {
    layout: wgpu::BindGroupLayout,
    sampler: wgpu::Sampler,
@@ -655,25 +563,33 @@ impl Post {
            self.finish_with(encoder, screen, &target.group, timing.as_deref_mut());
            return;
        };
-        let size = self.size().unwrap_or([1, 1]);
-        let frame = UpscaleFrame {
-            color: &target.color,
-            depth: &target.depth,
-            render_size: size,
-            output_size: taa.size,
-            jitter_clip: [self.taa_this_frame.jitter[0], self.taa_this_frame.jitter[1]],
-            jitter_pixels: self.jitter_pixels(),
-            reproject: self.taa_this_frame.reproject,
-            reset: self.taa_this_frame.jitter[2] > 0.5,
-            index: self.taa_frame,
-        };
-        let shown = res.resolve(queue, encoder, &frame, taa, timing.as_deref_mut());
+        let i = (self.taa_frame % 2) as usize;
+        queue.write_buffer(&res.uniform, 0, bytemuck::bytes_of(&self.taa_this_frame));
+        let attachments = [Some(wgpu::RenderPassColorAttachment {
+            view: &taa.history[i],
+            resolve_target: None,
+            depth_slice: None,
+            ops: wgpu::Operations {
+                load: wgpu::LoadOp::Clear(wgpu::Color::BLACK),
+                store: wgpu::StoreOp::Store,
+            },
+        })];
+        let mut pass = encoder.begin_render_pass(&wgpu::RenderPassDescriptor {
+            label: Some("Horizon TAA"),
+            timestamp_writes: timing.as_deref_mut().and_then(|t| t.writes("TAA")),
+            color_attachments: &attachments,
+            ..Default::default()
+        });
+        pass.set_pipeline(&res.pipeline);
+        pass.set_bind_group(0, &taa.resolve[i], &[]);
+        pass.draw(0..3, 0..1);
+        drop(pass);
        let pipeline = if self.upscale > 1.0 {
            &self.sharpen
        } else {
            &self.copy
        };
-        self.draw_onto(encoder, screen, shown, pipeline, timing);
+        self.draw_onto(encoder, screen, &taa.show[i], pipeline, timing);
    }

    /// Draw what `group` binds (`bind`) onto `screen`.
@@ -5,23 +5,9 @@
 use std::{fs, path::Path};

 pub const FILE: &str = "horizon-graphics.txt";
-/// Written beside it before a window's HDR output is switched on, naming the graphics driver it
-/// starts on ([`hdr_marker_text`]), and removed once the first HDR frame is presented. Found at
-/// the next start, it means HDR output took the game down there: HDR output is held back on
-/// that driver ([`Graphics::hdr_failed_start`]), and the mode stays as the player chose it.
+/// 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";
-/// The marker's text for a window whose HDR output starts on `driver`
-/// (`gfx::output::window_driver`).
-pub fn hdr_marker_text(driver: &str) -> String {
-    format!("driver:{driver}\n")
-}
-/// The driver a marker names; empty for one written before markers named it.
-fn marker_driver(text: &str) -> &str {
-    text.lines()
-        .find_map(|line| line.strip_prefix("driver:"))
-        .unwrap_or_default()
-        .trim()
-}

 /// What the system reports for the display HDR output goes to, in nits in HDR output's
 /// scale: where its SDR white sits (the desktop's white) and the peak. Each renderer keeps its
@@ -52,23 +38,6 @@ pub fn peak_step_of(nits: f32) -> f32 {
    };
    step.clamp(0.0, PEAK_STEPS as f32)
 }
-/// The steps of Paper White's and UI Brightness's scale: Auto (0), then 10 to 480 nits by 10.
-pub const NITS_STEPS: u32 = 48;
-/// Paper White's or UI Brightness's setting at slider position `v`, 0 to 1 ([`NITS_STEPS`]).
-pub fn nits_at(v: f32) -> u32 {
-    (v * NITS_STEPS as f32).round() as u32 * 10
-}
-/// Where a Paper White or UI Brightness setting sits on its slider, 0 to 1.
-pub fn nits_position(nits: u32) -> f32 {
-    nits as f32 / (NITS_STEPS * 10) as f32
-}
-/// A saved Paper White or UI Brightness: Auto (0), or 10 to 480 nits.
-fn nits_setting(nits: u32) -> u32 {
-    match nits {
-        0 => 0,
-        n => n.clamp(10, 480),
-    }
-}

 /// Simple-level presets. `Custom` leaves every option as the player set it.
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
@@ -521,6 +490,8 @@ pub fn reduced_far_detail_suggested() -> bool {
    REDUCED_SUGGESTED.load(std::sync::atomic::Ordering::Relaxed)
 }

+/// The name the options screen waits on to bind `Graphics::hdr_key`.
+pub const HDR_KEY: &str = "horizon.hdrSettings";
 /// The Screenshot Quality choices, times the game's resolution.
 pub const SCREENSHOT_QUALITIES: [u32; 4] = [1, 2, 4, 8];
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Default)]
@@ -830,17 +801,14 @@ pub struct Graphics {
    /// HDR black level: the display's darkest black, in hundredths of a nit; 0, the default,
    /// lifts nothing. Shadows are lifted onto it, and the HDR metadata says it.
    pub hdr_black_level: u32,
-    /// HDR brightness of the HUD and menus, in nits; 0 is Auto: at paper white
-    /// ([`Graphics::ui_nits`]). The first-person hand stays at the world's.
-    pub hdr_ui_nits: u32,
+    /// HDR brightness of the HUD and menus, in percent of paper white (25..=100); the
+    /// first-person hand stays at the world's.
+    pub hdr_ui_brightness: u32,
    /// HDR Lighting: Horizon's own HDR look, light sources, the sun and sunlight above paper
    /// white. Off, HDR output shows the same picture as SDR, for shader packs or the vanilla look.
    pub hdr_lighting: bool,
-    /// The graphics driver whose last start ended before HDR output showed a frame (the
-    /// marker found, [`HDR_MARKER`]): a window on it stays SDR whatever the mode, until the
-    /// mode is changed or the window starts on another driver ([`Graphics::hdr_held`]).
-    /// Empty for a marker that named no driver: the first one seen holds it.
-    pub hdr_failed_start: Option<String>,
+    /// A vanilla key name (`HDR_KEY`): opens HDR's settings from the game. Unbound by default.
+    pub hdr_key: String,
    /// Battery mode: at most 60 frames per second in a world and 30 in menus
    /// or behind other windows, and half the worker threads. Off by default;
    /// it changes when frames are drawn, never what they show or the ticks.
@@ -913,9 +881,9 @@ impl Default for Graphics {
            hdr_paper_white: 0,
            hdr_peak: 0,
            hdr_black_level: 0,
-            hdr_ui_nits: 0,
+            hdr_ui_brightness: 100,
            hdr_lighting: true,
-            hdr_failed_start: None,
+            hdr_key: "key.keyboard.unknown".into(),
            battery: false,
            shadow_cache: false,
            api: GraphicsApi::Auto,
@@ -941,54 +909,17 @@ impl Graphics {
                Vec::new()
            }
        };
-        let marker = dir.join(HDR_MARKER);
-        if let Ok(text) = fs::read_to_string(&marker)
-            && fs::remove_file(&marker).is_ok()
-            && g.hdr != HdrMode::Off
-        {
-            g.hdr_failed_start = Some(marker_driver(&text).to_owned());
+        if fs::remove_file(dir.join(HDR_MARKER)).is_ok() && g.hdr != HdrMode::Off {
+            g.hdr = HdrMode::Off;
            g.save(dir);
            log::warn!(
-                "the last start ended before HDR output showed a frame; HDR output stays off with that graphics driver until the HDR mode is changed (graphics option hdrFailedStart, in {FILE})"
+                "the last start ended before HDR output showed a frame; HDR is off now (graphics option hdr, in {FILE})"
            );
        }
        g
    }
-    /// Whether HDR output is held back on a window whose graphics driver is `driver`
-    /// (`gfx::output::window_driver`): the last start on it ended before HDR output
-    /// showed a frame ([`Graphics::hdr_failed_start`]).
-    pub fn hdr_held(&self, driver: &str) -> bool {
-        self.hdr_failed_start
-            .as_deref()
-            .is_some_and(|failed| failed.is_empty() || failed == driver)
-    }
-    /// The window's renderer runs on `driver`: a failed start that named no driver is this
-    /// one's now, and another driver's (a driver update, another GPU) is dropped, so HDR output
-    /// is tried again. True when it changed.
-    pub fn settle_failed_start(&mut self, driver: &str) -> bool {
-        match self.hdr_failed_start.as_deref() {
-            Some("") => self.hdr_failed_start = Some(driver.to_owned()),
-            Some(failed) if failed != driver => self.hdr_failed_start = None,
-            _ => return false,
-        }
-        true
-    }
-    /// `before`, as Undo brings it back, but never the hold on a driver HDR output failed to
-    /// start on: that stays as it is now, and goes when Undo changes the mode, as any change of
-    /// the mode drops it.
-    pub fn undone_to(&self, before: &Self) -> Self {
-        Self {
-            hdr_failed_start: self
-                .hdr_failed_start
-                .clone()
-                .filter(|_| self.hdr == before.hdr),
-            ..before.clone()
-        }
-    }
    pub fn parse(text: &str) -> Self {
        let mut g = Self::default();
-        // UI Brightness: `hdrUiNits`, else an older file's share of Paper White.
-        let (mut ui_nits, mut ui_share) = (None, None);
        for line in text.lines() {
            let Some((key, value)) = line.split_once(':') else {
                continue;
@@ -1078,9 +1009,12 @@ impl Graphics {
                "frameGeneration" => g.frame_generation = FrameGeneration::parse(value),
                "hdr" => g.hdr = HdrMode::parse(value, g.hdr),
                "hdrLighting" => g.hdr_lighting = flag(g.hdr_lighting),
-                "hdrPaperWhite" => g.hdr_paper_white = nits_setting(number(g.hdr_paper_white)),
-                "hdrUiNits" => ui_nits = value.parse().ok().map(nits_setting),
-                "hdrUiBrightness" => ui_share = value.parse::<u32>().ok(),
+                "hdrPaperWhite" => {
+                    g.hdr_paper_white = match number(g.hdr_paper_white) {
+                        0 => 0,
+                        n => n.clamp(10, 480),
+                    }
+                }
                "hdrPeak" => {
                    g.hdr_peak = match number(g.hdr_peak) {
                        0 => 0,
@@ -1088,7 +1022,10 @@ impl Graphics {
                    }
                }
                "hdrBlackLevel" => g.hdr_black_level = number(g.hdr_black_level).min(100),
-                "hdrFailedStart" => g.hdr_failed_start = Some(value.to_owned()),
+                "hdrUiBrightness" => {
+                    g.hdr_ui_brightness = number(g.hdr_ui_brightness).clamp(25, 100)
+                }
+                "hdrKey" if value.starts_with("key.") => g.hdr_key = value.to_owned(),
                "batteryMode" => g.battery = flag(g.battery),
                "shadowCache" => g.shadow_cache = flag(g.shadow_cache),
                "batchTranslucent" => g.translucent_batching = flag(g.translucent_batching),
@@ -1105,20 +1042,11 @@ impl Graphics {
                _ => {}
            }
        }
-        // The share was 25 to 100% of Paper White. 100% is Auto, and so is any share of an
-        // Auto Paper White, whose nits the file doesn't hold; another share of a Paper White set
-        // by hand is its nits, to the nearest step.
-        g.hdr_ui_nits = ui_nits.unwrap_or(match (ui_share, g.hdr_paper_white) {
-            (Some(share), paper) if share < 100 && paper != 0 => {
-                ((paper * share.max(25) + 500) / 1000).max(1) * 10
-            }
-            _ => 0,
-        });
        g
    }
    pub fn serialize(&self) -> String {
        let mut text = format!(
-            "preset:{}\nlodDistance:{}\nfarDetail:{}\ncaveCulling:{}\nentityCulling:{}\nentityCullingPrecheck:{}\nparticleCulling:{}\nleafCulling:{}\nopaqueIce:{}\nblockEntityCacheShulkerBoxes:{}\nblockEntityCacheSigns:{}\nblockEntityCacheDecoratedPots:{}\nblockEntityCacheBells:{}\nblockEntityCacheChests:{}\nblockEntityCacheBanners:{}\nblockEntityCacheCopperGolemStatues:{}\nchunkUpdates:{}\nuploadBudgetKiB:{}\ntextureBudgetMiB:{}\nsky:{}\nfog:{}\nweather:{}\nanimatedTextures:{}\nditherCutoutMips:{}\npresentMode:{}\nframePacing:{}\nworkers:{}\noverlay:{}\nresolutionScale:{}\nfxaa:{}\ntaa:{}\nupscaling:{}\nupscalingSharpness:{}\nscreenshotQuality:{}\nframeGeneration:{}\nhdr:{}\nhdrPaperWhite:{}\nhdrPeak:{}\nhdrBlackLevel:{}\nhdrUiNits:{}\nhdrLighting:{}\nbatteryMode:{}\nshadowCache:{}\ngraphicsApi:{}\npickedShaderPack:{}\nbatchTranslucent:{}\nhdrSmoothGradients:{}\ngpuCulling:{}\n",
+            "preset:{}\nlodDistance:{}\nfarDetail:{}\ncaveCulling:{}\nentityCulling:{}\nentityCullingPrecheck:{}\nparticleCulling:{}\nleafCulling:{}\nopaqueIce:{}\nblockEntityCacheShulkerBoxes:{}\nblockEntityCacheSigns:{}\nblockEntityCacheDecoratedPots:{}\nblockEntityCacheBells:{}\nblockEntityCacheChests:{}\nblockEntityCacheBanners:{}\nblockEntityCacheCopperGolemStatues:{}\nchunkUpdates:{}\nuploadBudgetKiB:{}\ntextureBudgetMiB:{}\nsky:{}\nfog:{}\nweather:{}\nanimatedTextures:{}\nditherCutoutMips:{}\npresentMode:{}\nframePacing:{}\nworkers:{}\noverlay:{}\nresolutionScale:{}\nfxaa:{}\ntaa:{}\nupscaling:{}\nupscalingSharpness:{}\nscreenshotQuality:{}\nframeGeneration:{}\nhdr:{}\nhdrPaperWhite:{}\nhdrPeak:{}\nhdrBlackLevel:{}\nhdrUiBrightness:{}\nhdrLighting:{}\nhdrKey:{}\nbatteryMode:{}\nshadowCache:{}\ngraphicsApi:{}\npickedShaderPack:{}\nbatchTranslucent:{}\nhdrSmoothGradients:{}\ngpuCulling:{}\n",
            self.preset.name(),
            self.lod_distance,
            self.far_detail.name(),
@@ -1165,8 +1093,9 @@ impl Graphics {
            self.hdr_paper_white,
            self.hdr_peak,
            self.hdr_black_level,
-            self.hdr_ui_nits,
+            self.hdr_ui_brightness,
            bool_text(self.hdr_lighting),
+            self.hdr_key,
            bool_text(self.battery),
            bool_text(self.shadow_cache),
            self.api.name(),
@@ -1175,12 +1104,17 @@ impl Graphics {
            bool_text(self.hdr_smooth_gradients),
            self.gpu_culling.key(),
        );
-        if let Some(driver) = &self.hdr_failed_start {
-            text += &format!("hdrFailedStart:{driver}\n");
-        }
        text += &self.blue_map.serialize();
        text
    }
+    /// Binds Horizon's graphics key `name` (`HDR_KEY`); false for another name.
+    pub fn set_key(&mut self, name: &str, value: String) -> bool {
+        match name {
+            HDR_KEY => self.hdr_key = value,
+            _ => return false,
+        }
+        true
+    }
    pub fn save(&self, dir: &Path) {
        let _ = fs::write(dir.join(FILE), self.serialize());
    }
@@ -1192,13 +1126,6 @@ impl Graphics {
            n => n,
        }
    }
-    /// The HUD and menus' brightness, in nits: the player's, or on Auto paper white's.
-    pub fn ui_nits(&self, reported: Option<Reported>) -> u32 {
-        match self.hdr_ui_nits {
-            0 => self.paper_white_nits(reported),
-            n => n,
-        }
-    }
    /// The peak the world's highlights reach, in nits: the player's, or on Auto
    /// what the system `reported`, else 1000.
    pub fn peak_nits(&self, reported: Option<Reported>) -> u32 {
@@ -1279,55 +1206,6 @@ pub fn apply_preset(preset: Preset, s: &mut crate::settings::Settings) {
 mod tests {
    use super::*;

-    /// UI Brightness is saved in nits, 0 for Auto. An older file's share of Paper White reads
-    /// as Auto at 100% or with Paper White on Auto, else as that share of it to the nearest step.
-    #[test]
-    fn ui_brightness_round_trips_in_nits_and_reads_older_shares() {
-        for (file, nits) in [
-            ("", 0),
-            ("hdrUiNits:0\n", 0),
-            ("hdrUiNits:160\n", 160),
-            ("hdrUiNits:5\n", 10),
-            ("hdrUiNits:9000\n", 480),
-            ("hdrUiNits:x\n", 0),
-            // Older files: 100% is Auto,
-            ("hdrPaperWhite:200\nhdrUiBrightness:100\n", 0),
-            // any share of Paper White's Auto too,
-            ("hdrUiBrightness:60\n", 0),
-            ("hdrPaperWhite:0\nhdrUiBrightness:25\n", 0),
-            // and another share of a Paper White set by hand is its nits.
-            ("hdrPaperWhite:200\nhdrUiBrightness:60\n", 120),
-            ("hdrUiBrightness:50\nhdrPaperWhite:203\n", 100),
-            ("hdrPaperWhite:250\nhdrUiBrightness:75\n", 190),
-            ("hdrPaperWhite:10\nhdrUiBrightness:25\n", 10),
-            ("hdrPaperWhite:480\nhdrUiBrightness:10\n", 120),
-            // The new key wins over the old one.
-            (
-                "hdrPaperWhite:200\nhdrUiBrightness:60\nhdrUiNits:300\n",
-                300,
-            ),
-            ("hdrUiNits:0\nhdrPaperWhite:200\nhdrUiBrightness:60\n", 0),
-        ] {
-            let g = Graphics::parse(file);
-            assert_eq!(g.hdr_ui_nits, nits, "{file}");
-            let saved = g.serialize();
-            assert!(!saved.contains("hdrUiBrightness"), "{file}");
-            assert!(saved.contains(&format!("\nhdrUiNits:{nits}\n")), "{file}");
-            assert_eq!(Graphics::parse(&saved), g, "{file}");
-        }
-        let mut g = Graphics::default();
-        assert_eq!(g.ui_nits(None), 203);
-        let reported = Some(Reported {
-            paper_white: 300,
-            peak: 1000,
-        });
-        assert_eq!(g.ui_nits(reported), 300);
-        g.hdr_paper_white = 120;
-        assert_eq!(g.ui_nits(reported), 120);
-        g.hdr_ui_nits = 400;
-        assert_eq!((g.ui_nits(None), g.ui_nits(reported)), (400, 400));
-    }
-
    #[test]
    fn hdr_modes_keep_boolean_files_and_round_trip_auto() {
        assert_eq!(Graphics::parse("").hdr, HdrMode::Off);
@@ -1365,85 +1243,6 @@ mod tests {
        }
    }

-    fn scratch(name: &str) -> std::path::PathBuf {
-        let dir = std::env::temp_dir().join(format!(
-            "horizon-{name}-{}-{:?}",
-            std::process::id(),
-            std::thread::current().id()
-        ));
-        let _ = fs::remove_dir_all(&dir);
-        fs::create_dir_all(&dir).unwrap();
-        dir
-    }
-
-    /// A start that finds the marker (HDR output took the last one down) keeps the mode the
-    /// player chose and saves the driver the marker names; HDR Off saves nothing.
-    #[test]
-    fn a_marker_keeps_the_mode_and_holds_the_driver_it_names() {
-        let driver = "Vulkan 10de:2684 NVIDIA GeForce RTX 4090; NVIDIA; 581.57";
-        for mode in HdrMode::ALL {
-            let dir = scratch(&format!("hdr-marker-{mode:?}"));
-            let saved = Graphics {
-                hdr: mode,
-                ..Graphics::default()
-            };
-            saved.save(&dir);
-            fs::write(dir.join(HDR_MARKER), hdr_marker_text(driver)).unwrap();
-            let g = Graphics::load(&dir);
-            let failed = (mode != HdrMode::Off).then(|| driver.to_owned());
-            assert_eq!((g.hdr, &g.hdr_failed_start), (mode, &failed), "{mode:?}");
-            assert!(!dir.join(HDR_MARKER).exists(), "{mode:?}");
-            // Saved for good: the next start, without a marker, reads the same.
-            let again = Graphics::load(&dir);
-            assert_eq!((again.hdr, again.hdr_failed_start), (mode, failed));
-            let _ = fs::remove_dir_all(&dir);
-        }
-    }
-
-    /// Today's marker names no driver: it holds whichever driver the window starts on first,
-    /// and is that driver's from then on.
-    #[test]
-    fn a_marker_without_a_driver_holds_the_first_one_seen() {
-        let dir = scratch("hdr-marker-legacy");
-        Graphics {
-            hdr: HdrMode::Auto,
-            ..Graphics::default()
-        }
-        .save(&dir);
-        fs::write(dir.join(HDR_MARKER), "HDR output was being switched on\n").unwrap();
-        let mut g = Graphics::load(&dir);
-        assert_eq!(
-            (g.hdr, g.hdr_failed_start.as_deref()),
-            (HdrMode::Auto, Some(""))
-        );
-        let (first, second) = (
-            "Vulkan 10de:2684 GPU; NVIDIA; 1",
-            "Dx12 1002:744c GPU; AMD; 2",
-        );
-        assert!(g.hdr_held(first) && g.hdr_held(second));
-        assert!(g.settle_failed_start(first));
-        assert!(g.hdr_held(first) && !g.hdr_held(second));
-        assert!(!g.settle_failed_start(first));
-        let _ = fs::remove_dir_all(&dir);
-    }
-
-    /// The window starting on another driver (an update, another GPU) drops the hold, so HDR
-    /// output is tried again; on the same driver it stays.
-    #[test]
-    fn another_driver_drops_the_hold() {
-        let held = "Vulkan 10de:2684 GPU; NVIDIA; 581.57";
-        let mut g = Graphics {
-            hdr: HdrMode::On,
-            hdr_failed_start: Some(held.into()),
-            ..Graphics::default()
-        };
-        assert!(!g.settle_failed_start(held));
-        assert!(g.hdr_held(held));
-        assert!(g.settle_failed_start("Vulkan 10de:2684 GPU; NVIDIA; 582.02"));
-        assert_eq!((g.hdr, g.hdr_failed_start), (HdrMode::On, None));
-        assert!(!Graphics::default().hdr_held(held));
-    }
-
    #[test]
    fn round_trips() {
        let g = Graphics {
@@ -1493,11 +1292,9 @@ mod tests {
            hdr_paper_white: 240,
            hdr_peak: 1400,
            hdr_black_level: 12,
-            hdr_ui_nits: 160,
+            hdr_ui_brightness: 60,
            hdr_lighting: false,
-            hdr_failed_start: Some(
-                "Vulkan 10de:2684 NVIDIA GeForce RTX 4090; NVIDIA; 581.57".into(),
-            ),
+            hdr_key: "key.keyboard.h".into(),
            battery: true,
            shadow_cache: true,
            api: GraphicsApi::Dx12,
@@ -1506,15 +1303,6 @@ mod tests {
            shader_pack: "Golden Hour".into(),
        };
        assert_eq!(Graphics::parse(&g.serialize()), g);
-        // A legacy marker's hold, which names no driver, round-trips too; none writes no line.
-        for failed in [Some(String::new()), None] {
-            let graphics = Graphics {
-                hdr_failed_start: failed,
-                ..Graphics::default()
-            };
-            assert_eq!(Graphics::parse(&graphics.serialize()), graphics);
-        }
-        assert!(!Graphics::default().serialize().contains("hdrFailedStart"));
        for mode in EntityCullingMode::ALL {
            let graphics = Graphics {
                entity_culling: mode,
@@ -1636,10 +1424,6 @@ mod tests {
            Graphics::parse("shaderPack:Pack.zip\n"),
            Graphics::default()
        );
-        // The HDR page's old shortcut key loads as nothing, and the next save drops it.
-        let old = Graphics::parse("hdr:true\nhdrKey:key.keyboard.h\nhdrPeak:1000\n");
-        assert_eq!((old.hdr, old.hdr_peak), (HdrMode::On, 1000));
-        assert!(!old.serialize().contains("hdrKey"));
        assert_eq!(
            Graphics::parse(
                "workers:abc\nsky:maybe\ncullLeaves:true\nentityCulling:maybe\nleafCulling:maybe\n"
@@ -14,7 +14,7 @@ use crate::{
    lang,
    options_ui::{Event, Page as OptionsPage},
    settings::{Opt, Settings},
-    settings_shell::{self as shell, Group, Output, Row, Screen, Sheet, Value},
+    settings_shell::{self as shell, Binding, Group, Output, Row, Screen, Sheet, Value},
    text::Text,
 };

@@ -106,6 +106,8 @@ pub enum H {
    FrameGeneration,
    Hdr,
    HdrBlackLevel,
+    /// Binds `Graphics::hdr_key`.
+    HdrKey,
    /// Starts HDR calibration (`crate::hdr_calibration`).
    HdrCalibrate,
    HdrPeak,
@@ -612,7 +614,7 @@ pub fn rows() -> Vec<(Page, Vec<(&'static str, Vec<Setting>)>)> {
                        h(
                            H::HdrUiBrightness,
                            None,
-                            "How bright the HUD and menus are. Auto: at paper white.",
+                            "How bright the HUD and menus are, against paper white.",
                        ),
                        h(
                            H::HdrLighting,
@@ -621,6 +623,14 @@ pub fn rows() -> Vec<(Page, Vec<(&'static str, Vec<Setting>)>)> {
                        ),
                    ],
                ),
+                (
+                    "Shortcut",
+                    vec![h(
+                        H::HdrKey,
+                        None,
+                        "A key that opens this screen from the game. Not bound at first.",
+                    )],
+                ),
            ],
        ),
    ];
@@ -698,10 +708,6 @@ fn setup_of(g: &crate::graphics::Graphics, reported: bool) -> Setup {
        Setup::Changed
    }
 }
-/// What the HDR page says while HDR output is held back on this window's graphics driver
-/// (`EffectiveOutput::held`): picking a mode tries again (`H::cycle`).
-const HDR_HELD: &str = "HDR output stopped the game the last time it started with this graphics driver. Choose a mode to try again.";
-
 /// The description beside `item` where it depends on [`setup`]; `text` otherwise.
 fn description(
    item: Item,
@@ -710,7 +716,6 @@ fn description(
    text: &'static str,
 ) -> &'static str {
    match (item, setup(s, out)) {
-        (Item::Horizon(H::Hdr), _) if out.held => HDR_HELD,
        (Item::Horizon(H::HdrCalibrate), Setup::Unknown) => {
            "Your display didn't say how bright it gets: calibrate to set it up."
        }
@@ -809,14 +814,14 @@ impl H {
            H::ResolutionScale => Some((g.resolution_scale as f32 - 50.0) / 150.0),
            H::UpscalingSharpness => Some(g.upscaling_sharpness as f32 / 100.0),
            // Auto, then 10..480 by 10.
-            H::HdrPaperWhite => Some(crate::graphics::nits_position(g.hdr_paper_white)),
-            H::HdrUiBrightness => Some(crate::graphics::nits_position(g.hdr_ui_nits)),
+            H::HdrPaperWhite => Some(g.hdr_paper_white as f32 / 480.0),
            // Auto, then the peak's scale.
            H::HdrPeak => Some(match g.hdr_peak {
                0 => 0.0,
                n => (1.0 + crate::graphics::peak_step_of(n as f32)) / PEAK_POSITIONS as f32,
            }),
            H::HdrBlackLevel => Some(g.hdr_black_level as f32 / 100.0),
+            H::HdrUiBrightness => Some((g.hdr_ui_brightness as f32 - 25.0) / 75.0),
            _ => None,
        }
    }
@@ -828,26 +833,13 @@ impl H {
            H::Workers => Some(max_workers()),
            H::ResolutionScale => Some(30),
            H::UpscalingSharpness => Some(20),
-            H::HdrPaperWhite | H::HdrUiBrightness => Some(crate::graphics::NITS_STEPS),
+            H::HdrPaperWhite => Some(48),
            H::HdrPeak => Some(PEAK_POSITIONS),
            H::HdrBlackLevel => Some(100),
+            H::HdrUiBrightness => Some(15),
            _ => None,
        }
    }
-    /// "Paper White: Auto (203)" or "Paper White: 160": a setting in nits, 0 for Auto, which
-    /// shows the nits Auto gives.
-    fn nits_label(self, s: &Settings, out: &EffectiveOutput) -> Text {
-        let (g, r) = (&s.horizon, out.reported);
-        let (caption, set, auto) = match self {
-            H::HdrPaperWhite => ("Paper White", g.hdr_paper_white, g.paper_white_nits(r)),
-            H::HdrPeak => ("Peak Brightness", g.hdr_peak, g.peak_nits(r)),
-            _ => ("UI Brightness", g.hdr_ui_nits, g.ui_nits(r)),
-        };
-        match set {
-            0 => labelled(caption, lang::tr("Auto (%s)", &[&auto])),
-            n => labelled(caption, n),
-        }
-    }
    fn label(self, s: &Settings, out: &EffectiveOutput) -> Text {
        let g = &s.horizon;
        match self {
@@ -948,9 +940,26 @@ impl H {
                Setup::Automatic => "Calibrate Anyway...",
                Setup::Changed => "Use Automatic Setup",
            })),
-            H::HdrPaperWhite | H::HdrPeak | H::HdrUiBrightness => self.nits_label(s, out),
+            H::HdrPaperWhite => match g.hdr_paper_white {
+                0 => labelled(
+                    "Paper White",
+                    lang::tr("Auto (%s)", &[&g.paper_white_nits(out.reported)]),
+                ),
+                n => labelled("Paper White", n.to_string()),
+            },
+            H::HdrPeak => match g.hdr_peak {
+                0 => labelled(
+                    "Peak Brightness",
+                    lang::tr("Auto (%s)", &[&g.peak_nits(out.reported)]),
+                ),
+                n => labelled("Peak Brightness", n.to_string()),
+            },
            H::HdrBlackLevel => labelled("Black Level", format!("{:.2}", g.black_level_nits())),
+            H::HdrUiBrightness => labelled_percent("UI Brightness", g.hdr_ui_brightness),
            H::HdrLighting => labelled("HDR Lighting", on_off(g.hdr_lighting)),
+            H::HdrKey => {
+                Text::translate("Shortcut: %s", &[crate::keybinds::display_name(&g.hdr_key)])
+            }
            H::BatteryMode => labelled("Battery Mode", on_off(g.battery)),
            H::ShadowCache => labelled("Shadow Cache", on_off(g.shadow_cache)),
            // A press across the row, as Calibrate...: the list it opens shows the pick.
@@ -991,8 +1000,7 @@ impl H {
            H::Workers => g.workers = (v * max_workers() as f32).round() as u32,
            H::ResolutionScale => g.resolution_scale = (50.0 + (v * 30.0).round() * 5.0) as u32,
            H::UpscalingSharpness => g.upscaling_sharpness = (v * 20.0).round() as u32 * 5,
-            H::HdrPaperWhite => g.hdr_paper_white = crate::graphics::nits_at(v),
-            H::HdrUiBrightness => g.hdr_ui_nits = crate::graphics::nits_at(v),
+            H::HdrPaperWhite => g.hdr_paper_white = (v * 48.0).round() as u32 * 10,
            H::HdrPeak => {
                g.hdr_peak = match (v * PEAK_POSITIONS as f32).round() as u32 {
                    0 => 0,
@@ -1000,6 +1008,7 @@ impl H {
                }
            }
            H::HdrBlackLevel => g.hdr_black_level = (v * 100.0).round() as u32,
+            H::HdrUiBrightness => g.hdr_ui_brightness = (25.0 + (v * 15.0).round() * 5.0) as u32,
            _ => {}
        }
    }
@@ -1077,9 +1086,7 @@ impl H {
            H::FrameGeneration => {
                g.frame_generation = step(&FrameGeneration::ALL, g.frame_generation, back)
            }
-            // Any choice tries HDR output again on a driver a start failed on.
            H::Hdr => {
-                g.hdr_failed_start = None;
                g.hdr = step(&HdrMode::ALL, g.hdr, back);
                if g.hdr == HdrMode::On && !out.hdr_offered() {
                    g.hdr = step(&HdrMode::ALL, g.hdr, back);
@@ -1148,11 +1155,7 @@ impl Item {
                | H::HdrUiBrightness
                | H::HdrLighting
                | H::HdrSmoothGradients,
-            ) if !out.requests_hdr(s.horizon.hdr) => Some(if out.held {
-                HDR_HELD
-            } else {
-                "Turn HDR on to use it."
-            }),
+            ) if !out.requests_hdr(s.horizon.hdr) => Some("Turn HDR on to use it."),
            Item::Horizon(H::TranslucentBatching)
                if !crate::graphics::translucent_batching_offered() =>
            {
@@ -1175,7 +1178,10 @@ impl Item {
    fn steps(self, s: &Settings, out: &EffectiveOutput) -> bool {
        self.switch(s, out).is_none()
            && self.slider(s).is_none()
-            && !matches!(self, Item::Horizon(H::HdrCalibrate | H::ShaderPacks))
+            && !matches!(
+                self,
+                Item::Horizon(H::HdrKey | H::HdrCalibrate | H::ShaderPacks)
+            )
    }
    /// On/off settings and their value.
    pub fn switch(self, s: &Settings, out: &EffectiveOutput) -> Option<bool> {
@@ -1330,6 +1336,12 @@ fn shown(item: Item, s: &Settings) -> bool {
 }
 /// A control's label as its name and its value ("Render Distance" and "12 chunks").
 fn parts(item: Item, s: &Settings, out: &EffectiveOutput) -> (String, Option<String>) {
+    // The shortcut's label is one translated "Shortcut: %s"; the row shows its key apart, as
+    // KeyBindsScreen does ("> key <" while it waits, `settings_shell::Value::Binding`).
+    if item == Item::Horizon(H::HdrKey) {
+        let key = crate::keybinds::display_name(&s.horizon.hdr_key).plain();
+        return (lang::get("Shortcut"), Some(key));
+    }
    shell::name_and_value(&item.label(s, out).plain())
 }

@@ -1338,9 +1350,13 @@ fn parts(item: Item, s: &Settings, out: &EffectiveOutput) -> (String, Option<Str
 fn row(setting: Setting, s: &Settings, out: &EffectiveOutput) -> Row<Item> {
    let item = setting.item;
    let (name, value) = parts(item, s, out);
-    let value = match (item.switch(s, out), item.slider(s)) {
-        (Some(on), _) => Value::Switch(on),
-        (None, Some(position)) => Value::Slider {
+    let value = match (item, item.switch(s, out), item.slider(s)) {
+        (Item::Horizon(H::HdrKey), ..) => Value::Binding(Binding::key(
+            crate::graphics::HDR_KEY,
+            value.unwrap_or_default(),
+        )),
+        (_, Some(on), _) => Value::Switch(on),
+        (_, None, Some(position)) => Value::Slider {
            position,
            steps: item.slider_steps(),
            text: value.unwrap_or_default(),
@@ -1506,7 +1522,7 @@ impl Screen for GraphicsScreen {
    /// one `horizon-ctl options-set` changed meanwhile), nor fullscreen, which F11 and the
    /// window manager change.
    fn undo(&mut self, s: &mut Settings, b: &Settings) -> Vec<Output> {
-        s.horizon = s.horizon.undone_to(&b.horizon);
+        s.horizon = b.horizon.clone();
        s.render_distance = b.render_distance;
        s.simulation_distance = b.simulation_distance;
        s.gamma = b.gamma;
@@ -1556,7 +1572,7 @@ mod tests {
    use super::*;
    use crate::{
        graphics_style as style,
-        settings_shell::{Columns, Hosted, Shell, Target},
+        settings_shell::{Capture, Columns, Hosted, Shell, Target},
    };
    use winit::keyboard::KeyCode as K;

@@ -2022,6 +2038,10 @@ mod tests {
            precheck.why.as_deref(),
            Some("Only applies to asynchronous entity culling.")
        );
+        let key = find(&s, Item::Horizon(H::HdrKey));
+        assert_eq!(key.name, "Shortcut");
+        let waits = Capture::Key(crate::graphics::HDR_KEY);
+        assert!(matches!(key.value, Value::Binding(ref b) if b.capture == waits));
        let calibrate = find(&s, Item::Horizon(H::HdrCalibrate));
        assert_eq!(calibrate.value, Value::Press);
    }
@@ -2706,7 +2726,7 @@ mod tests {
            H::HdrPaperWhite => s.horizon.hdr_paper_white,
            H::HdrPeak => s.horizon.hdr_peak,
            H::HdrBlackLevel => s.horizon.hdr_black_level,
-            H::HdrUiBrightness => s.horizon.hdr_ui_nits,
+            H::HdrUiBrightness => s.horizon.hdr_ui_brightness,
            _ => unreachable!(),
        };
        let fresh = || {
@@ -2,7 +2,7 @@
 //! reports.
 use super::tests::{CHANGED, CLICK, DRAGGED, FB, NONE, SIZE, Ui, offering, press, row, ui};
 use super::*;
-use crate::settings_shell::{Columns, Hosted};
+use crate::settings_shell::{Capture, Columns, Hosted};
 use winit::keyboard::KeyCode as K;

 #[test]
@@ -64,12 +64,17 @@ fn hdr_auto_can_be_selected_before_querying_and_brightness_waits_for_output() {
    let peak = row(&mut ui, &s, Item::Horizon(H::HdrPeak));
    assert_eq!(press(&mut ui, &mut s, (tx + 2.0, peak[1] + 4.0)), [DRAGGED]);
    ui.release();
-    // Calibrate starts the calibration.
+    // Calibrate starts the calibration; the shortcut row waits for a key.
    let calibrate = row(&mut ui, &s, Item::Horizon(H::HdrCalibrate));
    assert_eq!(
        press(&mut ui, &mut s, at(calibrate)),
        [CLICK, Output::Push(OptionsPage::HdrCalibration)]
    );
+    let key = row(&mut ui, &s, Item::Horizon(H::HdrKey));
+    assert_eq!(
+        press(&mut ui, &mut s, at(key)),
+        [CLICK, Output::Bind(Capture::Key(crate::graphics::HDR_KEY))]
+    );
    assert!(ui.changed());
 }

@@ -129,107 +134,3 @@ fn hdr_setup_follows_what_the_system_reported() {
    assert_eq!(setup_of(&g, true), Setup::Changed);
    assert_eq!(setup_of(&g, false), Setup::Unknown);
 }
-
-/// UI Brightness reads as Paper White does, in nits apart from it: Auto shows the paper white
-/// in use, and a value set by hand its own nits, whatever Paper White is. Its slider has Paper
-/// White's steps: Auto, then 10 to 480 nits by 10.
-#[test]
-fn ui_brightness_reads_in_nits_on_paper_whites_steps() {
-    let mut s = Settings::default();
-    s.horizon.hdr = HdrMode::On;
-    let reporting = offering(true, Some(true));
-    let label = |s: &Settings, out| Item::Horizon(H::HdrUiBrightness).label(s, out).plain();
-    assert_eq!(label(&s, &reporting), "UI Brightness: Auto (400)");
-    assert_eq!(label(&s, &NONE), "UI Brightness: Auto (203)");
-    s.horizon.hdr_paper_white = 250;
-    assert_eq!(label(&s, &reporting), "UI Brightness: Auto (250)");
-    s.horizon.hdr_ui_nits = 160;
-    for paper_white in [0, 80, 250] {
-        s.horizon.hdr_paper_white = paper_white;
-        assert_eq!(label(&s, &reporting), "UI Brightness: 160");
-    }
-    let item = Item::Horizon(H::HdrUiBrightness);
-    assert_eq!(
-        H::HdrUiBrightness.slider_steps(),
-        H::HdrPaperWhite.slider_steps()
-    );
-    H::HdrUiBrightness.set_slider(&mut s, 0.0);
-    let mut reached = vec![s.horizon.hdr_ui_nits];
-    for _ in 0..H::HdrUiBrightness.slider_steps().unwrap() {
-        item.step_slider(&mut s, true, 200.0, &reporting);
-        reached.push(s.horizon.hdr_ui_nits);
-    }
-    let paper: Vec<u32> = std::iter::once(0).chain((10..=480).step_by(10)).collect();
-    assert_eq!(reached, paper);
-    // Each value sits where Paper White's same value does.
-    for nits in paper {
-        s.horizon.hdr_ui_nits = nits;
-        s.horizon.hdr_paper_white = nits;
-        assert_eq!(item.slider(&s), Item::Horizon(H::HdrPaperWhite).slider(&s));
-    }
-}
-
-/// While HDR output is held back on this window's driver, the HDR row says so and keeps
-/// the mode; any change of the mode drops the hold, and HDR is asked for again.
-#[test]
-fn a_held_hdr_start_is_said_on_the_page_and_a_mode_change_tries_again() {
-    use crate::gfx::{HdrOutput, output::tests};
-    let mut s = Settings::default();
-    s.horizon.hdr = HdrMode::Auto;
-    s.horizon.hdr_failed_start = Some("Vulkan 10de:2684 GPU; driver; 1.0".into());
-    let (mut caps, reading) = tests::window(Some(HdrOutput::Pq), Some(true));
-    caps.held = true;
-    let out = tests::snapshot(&s.horizon, Default::default(), caps, reading);
-    let hdr = Item::Horizon(H::Hdr);
-    let setting = h(
-        H::Hdr,
-        Cost::None,
-        "Lava, fire and sunlight shine brighter than white.",
-    );
-    let held = super::row(setting, &s, &out);
-    assert_eq!(held.chosen.as_deref(), Some(HDR_HELD));
-    assert_eq!(held.why, None);
-    assert_eq!(hdr.label(&s, &out).plain(), "HDR: Auto");
-    assert_eq!(Item::Horizon(H::HdrPeak).blocked(&s, &out), Some(HDR_HELD));
-    // Not held, the row says what HDR does.
-    caps.held = false;
-    let free = tests::snapshot(&s.horizon, Default::default(), caps, reading);
-    assert_eq!(super::row(setting, &s, &free).chosen, None);
-    // Any step of the mode, either way, tries again.
-    for back in [false, true] {
-        let mut s = s.clone();
-        hdr.cycle(&mut s, back, FB, &out);
-        assert_ne!(s.horizon.hdr, HdrMode::Auto);
-        assert_eq!(s.horizon.hdr_failed_start, None);
-    }
-}
-
-/// Undo never brings the hold back: held Auto, changed to On (HDR tried again), then
-/// undone, is Auto without the hold. With the mode left alone, it keeps the hold as it is.
-#[test]
-fn undo_never_restores_a_held_hdr_start() {
-    let mut screen = GraphicsScreen {
-        framebuffer: FB,
-        output: NONE,
-    };
-    let mut opened = Settings::default();
-    opened.horizon.hdr = HdrMode::Auto;
-    opened.horizon.hdr_failed_start = Some("Vulkan 10de:2684 GPU; driver; 1.0; os".into());
-    let mut s = opened.clone();
-    let out = offering(true, Some(true));
-    Item::Horizon(H::Hdr).cycle(&mut s, true, FB, &out);
-    assert_eq!(
-        (s.horizon.hdr, &s.horizon.hdr_failed_start),
-        (HdrMode::On, &None)
-    );
-    screen.undo(&mut s, &opened);
-    assert_eq!(
-        (s.horizon.hdr, &s.horizon.hdr_failed_start),
-        (HdrMode::Auto, &None)
-    );
-    // Another row changed and undone: the hold stays.
-    let mut s = opened.clone();
-    s.horizon.fxaa = !s.horizon.fxaa;
-    screen.undo(&mut s, &opened);
-    assert_eq!(s.horizon, opened.horizon);
-}
@@ -206,9 +206,8 @@ fn display(light: vec3<f32>) -> vec4<f32> {
    let shows = params.world > 0.5 && params.peak > 1.0
        && (hand || (!covered && shows_world(f.rgb, w.rgb)));
    var light = lit(f.rgb, w.a, shows, true).light;
-    // The HUD and menus at their own brightness, by how much they cover, no brighter than the
-    // peak (as `fs_hdr_layered`): UI Brightness can pass paper white.
-    light = min(light * mix(1.0, params.ui, ui), vec3(params.peak));
+    // The HUD and menus at their own brightness, by how much they cover.
+    light *= mix(1.0, params.ui, ui);
    return display(light);
 }

@@ -276,8 +275,8 @@ fn backdrop(w: vec3<f32>) -> vec3<f32> {

 // The HUD over the world in gamma, the space the HUD blends in: its own part, what its backdrop
 // B doesn't explain (H = P - (1 - c) B, exact for the layering blends), at UI Brightness, over
-// (1 - c) of the world, light above white included. Where the world is at or below white, with
-// UI Brightness at paper white, that is the HUD's picture as drawn.
+// (1 - c) of the world, light above white included. Where the world is at or below white, at
+// 100%, that is the HUD's picture as drawn.
 fn layered(at: vec2<i32>) -> vec3<f32> {
    let w = max(textureLoad(frame, at, 0).rgb, vec3(0.0));
    let p = textureLoad(hud, at, 0).rgb;
@@ -17,7 +17,6 @@
 //! Nothing changes until Save, which writes the three into Horizon's settings; Cancel
 //! or Escape leaves them as they were.
 use crate::{
-    font::Font,
    hud::{HudAtlas, HudBatch, rgba},
    lang,
    settings::Settings,
@@ -34,10 +33,6 @@ pub enum Step {
 }
 const STEPS: [Step; 3] = [Step::Black, Step::Peak, Step::PaperWhite];

-/// A step's test picture for HDR output: the step, its nits and where the controls start (a
-/// share of the height).
-pub type Picture = (Step, f32, f32);
-
 /// What the options screen does after an input here.
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum Outcome {
@@ -48,30 +43,6 @@ pub enum Outcome {
    Cancel,
 }

-/// The window as calibration found it: calibration turns it fullscreen for its test pictures,
-/// and gives it back as it was.
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
-pub enum WindowState {
-    Fullscreen,
-    Maximized,
-    Windowed,
-}
-
-impl WindowState {
-    pub fn of(fullscreen: bool, maximized: bool) -> Self {
-        match (fullscreen, maximized) {
-            (true, _) => Self::Fullscreen,
-            (false, true) => Self::Maximized,
-            (false, false) => Self::Windowed,
-        }
-    }
-    /// On leaving calibration: whether the window leaves fullscreen, and whether it is
-    /// maximized again after (leaving fullscreen gives back its restored size on Windows).
-    pub fn leaving(self) -> (bool, bool) {
-        (self != Self::Fullscreen, self == Self::Maximized)
-    }
-}
-
 pub struct Calibration {
    step: usize,
    /// Nits, in the order of `STEPS`.
@@ -82,11 +53,8 @@ pub struct Calibration {
    dragging: bool,
 }

-/// Height of the band of controls at the bottom with a hint of one line, in GUI pixels.
+/// Height of the band of controls at the bottom, in GUI pixels.
 const BAND: f32 = 84.0;
-/// Each further line of the hint, which wraps within the window less this at each side.
-const HINT_LINE: f32 = 10.0;
-const HINT_MARGIN: f32 = 10.0;

 impl Step {
    /// The slider's steps past its first: the settings' own.
@@ -147,24 +115,18 @@ impl Step {

 struct Layout {
    top: f32,
-    hint: Vec<Text>,
    slider: (f32, f32, f32),
    cancel: (f32, f32, f32),
    back: (f32, f32, f32),
    next: (f32, f32, f32),
 }
-/// The band grows up by the lines `step`'s hint takes past its first.
-fn layout(font: &Font, step: Step, (w, h): (f32, f32)) -> Layout {
-    let hint = Text::literal(lang::get(step.hint_key()));
-    let hint = font.split(&hint, w - 2.0 * HINT_MARGIN);
-    let more = hint.len().saturating_sub(1) as f32 * HINT_LINE;
-    let top = (h - BAND - more).floor();
+fn layout(w: f32, h: f32) -> Layout {
+    let top = (h - BAND).floor();
    let cx = (w / 2.0).floor();
-    let by = top + more + 58.0;
+    let by = top + 58.0;
    Layout {
        top,
-        hint,
-        slider: (cx - 100.0, top + more + 32.0, 200.0),
+        slider: (cx - 100.0, top + 32.0, 200.0),
        cancel: (cx - 152.0, by, 98.0),
        back: (cx - 49.0, by, 98.0),
        next: (cx + 54.0, by, 98.0),
@@ -197,9 +159,6 @@ impl Calibration {
    fn current(&self) -> Step {
        STEPS[self.step]
    }
-    fn layout(&self, font: &Font, size: (f32, f32)) -> Layout {
-        layout(font, self.current(), size)
-    }
    /// The slider's position, 0..=1.
    fn position(&self) -> f32 {
        let step = self.current();
@@ -225,17 +184,18 @@ impl Calibration {
        };
        Text::literal(format!("{}: {}", step.name(), value))
    }
-    /// The current step's test picture in a GUI of `size`.
-    pub fn picture(&self, font: &Font, size: (f32, f32)) -> Picture {
+    /// The step, its nits and where the controls start (a share of the height), for
+    /// HDR output's test picture.
+    pub fn picture(&self, h: f32) -> (Step, f32, f32) {
        (
            self.current(),
            self.values[self.step],
-            self.layout(font, size).top / size.1.max(1.0),
+            layout(0.0, h).top / h.max(1.0),
        )
    }
    pub fn draw(&self, batch: &mut HudBatch, atlas: &HudAtlas, cursor: (f32, f32)) {
        let (w, h) = (batch.width, batch.height);
-        let l = self.layout(&atlas.font, (w, h));
+        let l = layout(w, h);
        // Above the band HDR output draws the test picture over whatever is here.
        batch.fill(atlas, 0.0, 0.0, w, h, rgba(0, 0, 0, 255));
        batch.fill(atlas, 0.0, l.top, w, h - l.top, rgba(24, 24, 24, 255));
@@ -245,10 +205,16 @@ impl Calibration {
            &[&(self.step + 1), &STEPS.len(), &step.name()],
        ));
        ui::centered_text(batch, atlas, &title, 0.0, l.top + 6.0, w, u32::MAX);
-        for (i, line) in l.hint.iter().enumerate() {
-            let y = l.top + 18.0 + i as f32 * HINT_LINE;
-            ui::centered_text(batch, atlas, line, 0.0, y, w, rgba(160, 160, 160, 255));
-        }
+        let hint = Text::literal(lang::get(step.hint_key()));
+        ui::centered_text(
+            batch,
+            atlas,
+            &hint,
+            0.0,
+            l.top + 18.0,
+            w,
+            rgba(160, 160, 160, 255),
+        );
        let (x, y, sw) = l.slider;
        ui::slider(
            batch,
@@ -295,14 +261,8 @@ impl Calibration {
        }
    }
    /// A press, or a drag with `drag`, at `cursor`.
-    pub fn click(
-        &mut self,
-        font: &Font,
-        cursor: (f32, f32),
-        size: (f32, f32),
-        drag: bool,
-    ) -> Outcome {
-        let l = self.layout(font, size);
+    pub fn click(&mut self, cursor: (f32, f32), (w, h): (f32, f32), drag: bool) -> Outcome {
+        let l = layout(w, h);
        let (x, _, sw) = l.slider;
        if drag {
            if !self.dragging {
@@ -376,14 +336,6 @@ mod tests {

    const NONE: EffectiveOutput = EffectiveOutput::NONE;

-    fn font() -> Font {
-        Font::metrics(std::path::Path::new("/nonexistent/horizon-test-assets"))
-    }
-    /// At the default GUI scale of the game's first window (854 x 480 at 2).
-    fn picture(c: &Calibration) -> Picture {
-        c.picture(&font(), (427.0, 240.0))
-    }
-
    #[test]
    fn calibration_saves_only_on_save() {
        let mut s = Settings::default();
@@ -392,14 +344,14 @@ mod tests {
        let mut c = Calibration::new(&s, &NONE);
        assert_eq!(c.key(KeyCode::ArrowLeft), Outcome::Changed);
        assert_eq!(c.key(KeyCode::ArrowLeft), Outcome::Changed);
-        assert!((picture(&c).1 - 0.03).abs() < 1e-6);
+        assert!((c.picture(100.0).1 - 0.03).abs() < 1e-6);
        assert_eq!(c.key(KeyCode::Escape), Outcome::Cancel);
        assert_eq!(s.horizon, before);
        // Black, then Peak (one step up), then Paper White, then Save.
        assert_eq!(c.key(KeyCode::Enter), Outcome::Click);
        assert_eq!(c.key(KeyCode::ArrowRight), Outcome::Changed);
        assert_eq!(c.key(KeyCode::Enter), Outcome::Click);
-        assert_eq!(picture(&c).0, Step::PaperWhite);
+        assert_eq!(c.picture(100.0).0, Step::PaperWhite);
        assert_eq!(c.key(KeyCode::Enter), Outcome::Save);
        c.save(&mut s);
        assert_eq!(s.horizon.hdr_black_level, 3);
@@ -418,10 +370,10 @@ mod tests {
        for (output, peak, paper_white) in [(&reporting, 1000.0, 400.0), (&NONE, 1000.0, 203.0)] {
            let mut c = Calibration::new(&s, output);
            c.key(KeyCode::Enter);
-            assert_eq!(picture(&c).0, Step::Peak);
-            assert_eq!(picture(&c).1, peak);
+            assert_eq!(c.picture(1.0).0, Step::Peak);
+            assert_eq!(c.picture(1.0).1, peak);
            c.key(KeyCode::Enter);
-            assert_eq!(picture(&c).1, paper_white);
+            assert_eq!(c.picture(1.0).1, paper_white);
        }
    }

@@ -440,14 +392,14 @@ mod tests {
        ];
        let mut c = Calibration::new(&Settings::default(), &NONE);
        for (i, expected) in expected.iter().enumerate() {
-            assert_eq!(picture(&c).0, STEPS[i]);
+            assert_eq!(c.picture(1.0).0, STEPS[i]);
            for _ in 0..200 {
                c.key(KeyCode::ArrowLeft);
            }
-            let mut seen = vec![picture(&c).1];
+            let mut seen = vec![c.picture(1.0).1];
            for _ in 0..200 {
                c.key(KeyCode::ArrowRight);
-                let v = picture(&c).1;
+                let v = c.picture(1.0).1;
                if seen.last() != Some(&v) {
                    seen.push(v);
                }
@@ -470,7 +422,7 @@ mod tests {
        assert_eq!(s.horizon.hdr_black_level, 2);
        // Calibrated back down, 0 is no lift: what the step showed.
        let mut c = Calibration::new(&s, &NONE);
-        assert!((picture(&c).1 - 0.02).abs() < 1e-6);
+        assert!((c.picture(1.0).1 - 0.02).abs() < 1e-6);
        c.key(KeyCode::ArrowLeft);
        c.key(KeyCode::ArrowLeft);
        c.key(KeyCode::Enter);
@@ -483,89 +435,14 @@ mod tests {
        assert_eq!(s.horizon.hdr_peak, 10_000);
        let mut c = Calibration::new(&s, &NONE);
        c.key(KeyCode::Enter);
-        assert_eq!(picture(&c).1, 10_000.0);
+        assert_eq!(c.picture(1.0).1, 10_000.0);
        // One step down from the top is 500 nits; from 2000, 50.
        c.key(KeyCode::ArrowLeft);
-        assert_eq!(picture(&c).1, 9500.0);
+        assert_eq!(c.picture(1.0).1, 9500.0);
        s.horizon.hdr_peak = 2000;
        let mut c = Calibration::new(&s, &NONE);
        c.key(KeyCode::Enter);
        c.key(KeyCode::ArrowLeft);
-        assert_eq!(picture(&c).1, 1950.0);
-    }
-
-    /// A hint wider than the window less its margins wraps, the band grows up by the lines
-    /// it adds, and the test picture ends where the band drawn starts.
-    #[test]
-    fn the_hint_wraps_and_the_band_grows_by_its_lines() {
-        let font = font();
-        let mut c = Calibration::new(&Settings::default(), &NONE);
-        c.key(KeyCode::Enter);
-        c.key(KeyCode::Enter);
-        let hint = Text::literal(lang::get(Step::PaperWhite.hint_key()));
-        let wide = font.width_text(&hint);
-        let size = (wide + 2.0 * HINT_MARGIN, 240.0);
-        let one = c.layout(&font, size);
-        assert_eq!(one.hint.len(), 1);
-        assert_eq!(one.top, 240.0 - BAND);
-        let narrow = (wide * 0.6, 240.0);
-        let wrapped = c.layout(&font, narrow);
-        assert_eq!(wrapped.hint.len(), 2);
-        assert!(
-            wrapped
-                .hint
-                .iter()
-                .all(|l| font.width_text(l) <= narrow.0 - 2.0 * HINT_MARGIN)
-        );
-        assert_eq!(wrapped.top, 240.0 - BAND - HINT_LINE);
-        // Under the hint's lines, the controls keep their place in the band.
-        assert_eq!(
-            wrapped.slider.1 - wrapped.top,
-            one.slider.1 - one.top + HINT_LINE
-        );
-        assert_eq!(
-            wrapped.next.1 - wrapped.top,
-            one.next.1 - one.top + HINT_LINE
-        );
-        for size in [size, narrow] {
-            let (_, _, band) = c.picture(&font, size);
-            assert_eq!(band * size.1, c.layout(&font, size).top);
-        }
-    }
-
-    /// The Peak step's patch (a square of a tenth of the screen, centred above the band,
-    /// `hdr.wgsl`) stays above the band even on the narrowest GUI with every hint wrapped:
-    /// its side is no more than the band's top.
-    #[test]
-    fn the_test_pictures_stay_above_a_grown_band() {
-        let font = font();
-        let mut c = Calibration::new(&Settings::default(), &NONE);
-        for step in STEPS {
-            for (w, h) in [(320.0, 240.0), (200.0, 240.0), (427.0, 240.0)] {
-                let (shown, _, band) = c.picture(&font, (w, h));
-                assert_eq!(shown, step);
-                let side = (0.1 * w * h).sqrt();
-                assert!(
-                    side <= band * h,
-                    "{step:?} at {w}x{h}: {side} > {}",
-                    band * h
-                );
-            }
-            c.key(KeyCode::Enter);
-        }
-    }
-
-    /// Leaving calibration gives the window back as it found it.
-    #[test]
-    fn leaving_gives_the_window_back_as_it_was() {
-        use WindowState as W;
-        assert_eq!(W::of(true, false), W::Fullscreen);
-        assert_eq!(W::of(true, true), W::Fullscreen);
-        assert_eq!(W::of(false, true), W::Maximized);
-        assert_eq!(W::of(false, false), W::Windowed);
-        // (leave fullscreen, maximize again)
-        assert_eq!(W::Fullscreen.leaving(), (false, false));
-        assert_eq!(W::Maximized.leaving(), (true, true));
-        assert_eq!(W::Windowed.leaving(), (true, false));
+        assert_eq!(c.picture(1.0).1, 1950.0);
    }
 }
@@ -12,7 +12,6 @@ use std::{
 };
 use wgpu::util::DeviceExt;

-mod animate;
 pub mod cit_glint;
 mod pack_text;
 pub mod pictures;
@@ -101,13 +100,13 @@ pub struct HudAtlas {
    pub glint_armor: (Vec<u8>, u32, u32),
    /// A resource pack's own `core/text` shader for the GUI's text, translated;
    /// none draws the text natively.
-    pub text_shader: Option<std::sync::Arc<crate::core_shader::CoreProgram>>,
+    pub text_shader: Option<std::sync::Arc<horizon_shaders::CoreProgram>>,
    /// A resource pack's own `core/rendertype_lines` shader for the block outline, translated;
    /// none draws the outline natively.
-    pub lines_shader: Option<std::sync::Arc<crate::core_shader::CoreProgram>>,
+    pub lines_shader: Option<std::sync::Arc<horizon_shaders::CoreProgram>>,
    /// The packs' `core/sky` and `core/stars`, when a pack replaces them.
-    pub sky_shader: Option<std::sync::Arc<crate::core_shader::CoreProgram>>,
-    pub stars_shader: Option<std::sync::Arc<crate::core_shader::CoreProgram>>,
+    pub sky_shader: Option<std::sync::Arc<horizon_shaders::CoreProgram>>,
+    pub stars_shader: Option<std::sync::Arc<horizon_shaders::CoreProgram>>,
    /// The packs' Polytone screen sprite modifiers.
    pub sprite_modifiers: std::sync::Arc<sprite_modifiers::SpriteModifiers>,
    /// The packs' OptiFine random entity textures, whose variants this atlas packs.
@@ -1428,7 +1427,32 @@ impl HudAtlas {
        }
        if full {
            // Official Recipes artwork from Just Enough Items, under MIT.
-            for (name, png) in crate::jei_sprites::SPRITES {
+            for (name, png) in [
+                (
+                    "button_enabled_v2",
+                    include_bytes!("jei_recipes/button_enabled_v2.png").as_slice(),
+                ),
+                (
+                    "button_disabled_v2",
+                    include_bytes!("jei_recipes/button_disabled_v2.png").as_slice(),
+                ),
+                (
+                    "button_highlight_v2",
+                    include_bytes!("jei_recipes/button_highlight_v2.png").as_slice(),
+                ),
+                (
+                    "icons/arrow_previous_v2",
+                    include_bytes!("jei_recipes/icons/arrow_previous_v2.png").as_slice(),
+                ),
+                (
+                    "icons/arrow_next_v2",
+                    include_bytes!("jei_recipes/icons/arrow_next_v2.png").as_slice(),
+                ),
+                (
+                    "search_background_v2",
+                    include_bytes!("jei_recipes/search_background_v2.png").as_slice(),
+                ),
+            ] {
                let (width, height, rgba) = decode_bytes(png)?;
                images.push((format!("horizon/jei/{name}"), width, height, rgba));
            }
@@ -2871,12 +2895,65 @@ impl HudRenderer {
    pub fn set_text_shader(
        &mut self,
        device: &wgpu::Device,
-        shader: Option<&crate::core_shader::CoreProgram>,
+        shader: Option<&horizon_shaders::CoreProgram>,
    ) {
        self.pack_text = shader.and_then(|shader| {
            pack_text::PackText::new(device, self.format, &self.atlas_view, shader, self.coverage)
        });
    }
+    pub fn animate_sprites(
+        &mut self,
+        uploads: &mut crate::gfx::upload::Uploads,
+        encoder: &mut wgpu::CommandEncoder,
+        tick: u64,
+    ) {
+        let Some(texture) = &self.atlas_texture else {
+            return;
+        };
+        for (rect, animation, previous) in &mut self.sprite_animations {
+            // `SpriteContents.AnimationState`: the frame from the mcmeta's
+            // list, blended into the next one by the sub-frame's thousandths
+            // when the sprite interpolates.
+            let blend = animation.blend(tick);
+            let state = (blend.frame, blend.next, blend.millis);
+            if state == *previous {
+                continue;
+            }
+            let (w, h) = rect.texels((texture.width(), texture.height()));
+            let pixels = if blend.millis == 0 {
+                animation.resized_pixels(blend.frame, w, h)
+            } else {
+                let current = animation.resized_pixels(blend.frame, w, h);
+                let next = animation.resized_pixels(blend.next, w, h);
+                let millis = blend.millis;
+                current
+                    .iter()
+                    .zip(next)
+                    .map(|(&a, b)| {
+                        ((u32::from(a) * (1000 - millis) + u32::from(b) * millis + 500) / 1000)
+                            as u8
+                    })
+                    .collect()
+            };
+            uploads.texture(
+                encoder,
+                wgpu::TexelCopyTextureInfo {
+                    texture,
+                    mip_level: 0,
+                    origin: wgpu::Origin3d {
+                        x: (rect.u0 * texture.width() as f32).round() as u32,
+                        y: (rect.v0 * texture.height() as f32).round() as u32,
+                        z: 0,
+                    },
+                    aspect: wgpu::TextureAspect::All,
+                },
+                w,
+                h,
+                &pixels,
+            );
+            *previous = state;
+        }
+    }
    /// Stage `patches` into the shared atlas texture.
    pub fn upload_patches(
        &self,
@@ -1,61 +0,0 @@
-//! The GUI atlas's animated sprites, frame by frame (vanilla's or a Polytone `mode`'s).
-
-impl super::HudRenderer {
-    /// Shows each animated sprite's frame: its mcmeta's, or what its Polytone `mode` picks.
-    pub(crate) fn animate(
-        &mut self,
-        uploads: &mut crate::gfx::upload::Uploads,
-        encoder: &mut wgpu::CommandEncoder,
-        tick: u64,
-        animator: &crate::gfx::animate::SpriteAnimator,
-    ) {
-        let inputs = animator.mode_inputs();
-        let inputs = Some(&inputs);
-        let Some(texture) = &self.atlas_texture else {
-            return;
-        };
-        for (rect, animation, previous) in &mut self.sprite_animations {
-            // `SpriteContents.AnimationState`: the frame from the mcmeta's
-            // list, blended into the next one by the sub-frame's thousandths
-            // when the sprite interpolates; or what a Polytone `mode` picks.
-            let blend = animation.blend_with(tick, inputs);
-            let state = (blend.frame, blend.next, blend.millis);
-            if state == *previous {
-                continue;
-            }
-            let (w, h) = rect.texels((texture.width(), texture.height()));
-            let pixels = if blend.millis == 0 {
-                animation.resized_pixels(blend.frame, w, h)
-            } else {
-                let current = animation.resized_pixels(blend.frame, w, h);
-                let next = animation.resized_pixels(blend.next, w, h);
-                let millis = blend.millis;
-                current
-                    .iter()
-                    .zip(next)
-                    .map(|(&a, b)| {
-                        ((u32::from(a) * (1000 - millis) + u32::from(b) * millis + 500) / 1000)
-                            as u8
-                    })
-                    .collect()
-            };
-            uploads.texture(
-                encoder,
-                wgpu::TexelCopyTextureInfo {
-                    texture,
-                    mip_level: 0,
-                    origin: wgpu::Origin3d {
-                        x: (rect.u0 * texture.width() as f32).round() as u32,
-                        y: (rect.v0 * texture.height() as f32).round() as u32,
-                        z: 0,
-                    },
-                    aspect: wgpu::TextureAspect::All,
-                },
-                w,
-                h,
-                &pixels,
-            );
-            *previous = state;
-        }
-    }
-}
@@ -393,7 +393,7 @@ fn coverage_uses_pack_texts_final_alpha_and_discard() {
        return;
    };
    // A translated-style struct result and early return; no dependency on game resources.
-    let program = crate::core_shader::CoreProgram {
+    let program = horizon_shaders::CoreProgram {
        vertex: naga::front::wgsl::parse_str("@vertex fn main(@location(0) p: vec2<f32>) -> @builtin(position) vec4<f32> { return vec4(p.x / 2.0 - 1.0, 1.0 - p.y, 0.0, 1.0); }").unwrap(),
        fragment: naga::front::wgsl::parse_str("struct Result { @location(0) color: vec4<f32> } @fragment fn main(@builtin(position) p: vec4<f32>) -> Result { if p.x > 2.0 { discard; } return Result(vec4(0.4, 0.2, 0.1, 0.5)); }").unwrap(),
    };
@@ -414,7 +414,7 @@ fn a_pack_text_shader_without_a_colour_output_is_dropped_not_wrapped() {
    let Some(mut gpu) = Gpu::new() else {
        return;
    };
-    let program = crate::core_shader::CoreProgram {
+    let program = horizon_shaders::CoreProgram {
        vertex: naga::front::wgsl::parse_str("@vertex fn main(@location(0) p: vec2<f32>) -> @builtin(position) vec4<f32> { return vec4(p, 0.0, 1.0); }").unwrap(),
        fragment: naga::front::wgsl::parse_str("@fragment fn main() -> @location(1) vec4<f32> { return vec4(1.0); }").unwrap(),
    };
@@ -5,7 +5,7 @@
 use std::path::Path;
 use std::sync::Arc;

-use crate::core_shader::{CoreProgram, Glue};
+use horizon_shaders::{CoreProgram, Glue};

 use super::{HudBatch, HudVertex};
 use crate::gfx::hud_coverage::Pipeline;
@@ -64,7 +64,7 @@ pub(super) fn load_core(
        let path = format!("assets/{namespace}/{path}");
        read(root, &path).or_else(|| read(defaults, &path))
    };
-    match crate::core_shader::translate_core(&vertex, &fragment, defines, &include, glue) {
+    match horizon_shaders::translate_core(&vertex, &fragment, defines, &include, glue) {
        Ok(program) => {
            log::info!("the resource pack's {name} shader is used");
            Some(Arc::new(program))
@@ -132,7 +132,7 @@ impl PackText {
                count: None,
            })
            .collect();
-        for (_, binding) in crate::core_shader::SAMPLERS {
+        for (_, binding) in horizon_shaders::SAMPLERS {
            entries.push(wgpu::BindGroupLayoutEntry {
                binding,
                visibility,
@@ -175,7 +175,7 @@ impl PackText {
                }),
            })
            .collect();
-        for (_, binding) in crate::core_shader::SAMPLERS {
+        for (_, binding) in horizon_shaders::SAMPLERS {
            resources.push(wgpu::BindGroupEntry {
                binding,
                resource: wgpu::BindingResource::TextureView(atlas),
@@ -1,55 +0,0 @@
-//! The official Recipes viewer's artwork from Just Enough Items, under MIT (`jei_recipes/LICENSE.txt`,
-//! THIRD_PARTY_NOTICES.md): `HudAtlas` loads each as the sprite `horizon/jei/<name>`.
-
-/// Each sprite's name and its PNG.
-pub(crate) const SPRITES: &[(&str, &[u8])] = &[
-    (
-        "button_enabled_v2",
-        include_bytes!("jei_recipes/button_enabled_v2.png"),
-    ),
-    (
-        "button_disabled_v2",
-        include_bytes!("jei_recipes/button_disabled_v2.png"),
-    ),
-    (
-        "button_highlight_v2",
-        include_bytes!("jei_recipes/button_highlight_v2.png"),
-    ),
-    (
-        "icons/arrow_previous_v2",
-        include_bytes!("jei_recipes/icons/arrow_previous_v2.png"),
-    ),
-    (
-        "icons/arrow_next_v2",
-        include_bytes!("jei_recipes/icons/arrow_next_v2.png"),
-    ),
-    (
-        "search_background_v2",
-        include_bytes!("jei_recipes/search_background_v2.png"),
-    ),
-    ("slot", include_bytes!("jei_recipes/slot.png")),
-    (
-        "icons/list_badge",
-        include_bytes!("jei_recipes/icons/list_badge.png"),
-    ),
-    (
-        "interactive_ingredient_tooltip_background",
-        include_bytes!("jei_recipes/interactive_ingredient_tooltip_background.png"),
-    ),
-    (
-        "recipe_preview_background_v2",
-        include_bytes!("jei_recipes/recipe_preview_background_v2.png"),
-    ),
-    (
-        "ingredient_list_slot_background_v2",
-        include_bytes!("jei_recipes/ingredient_list_slot_background_v2.png"),
-    ),
-    (
-        "scrollbar_background_v2",
-        include_bytes!("jei_recipes/scrollbar_background_v2.png"),
-    ),
-    (
-        "scrollbar_marker_v2",
-        include_bytes!("jei_recipes/scrollbar_marker_v2.png"),
-    ),
-];
@@ -38,7 +38,6 @@ pub mod command_block;
 pub mod connected;
 pub mod containers;
 pub mod controller_ui;
-pub mod core_shader;
 pub mod crash;
 pub mod custom_sky;
 pub mod datapack;
@@ -63,12 +62,10 @@ pub mod hud_layout;
 pub mod hud_overlays;
 pub mod inventory_effects;
 pub mod java_text;
-mod jei_sprites;
 pub mod jigsaw_block;
 pub mod keypad;
 pub mod terrain_model;
 pub use horizon_polytone::colors as polytone_colors;
-pub use horizon_polytone::creative_tabs as polytone_creative_tabs;
 pub use horizon_world::json_folder;
 pub mod level_loading;
 pub mod light;
@@ -89,8 +86,6 @@ pub mod options_fixes;
 pub mod options_ui;
 pub mod overlay;
 pub mod pack_browser;
-pub mod pack_formats;
-pub mod pack_hooks;
 pub mod pack_options_ui;
 pub mod pack_palette;
 pub mod pack_screen;
@@ -761,49 +761,6 @@ pub struct MeshTables {
    colormaps: Vec<Arc<crate::environment::Colormap>>,
    water_colormap: Option<u16>,
 }
-/// Vanilla's four biome colour functions (`BiomeColors`) with what the packs replace them by:
-/// `biome_colors` (a colormap or a flat colour), else the colormap a block modifier gives
-/// `grass_block`, `oak_leaves` or `leaf_litter`, or a fluid modifier gives water, which Polytone
-/// spreads to every block of that function. Each with the tints that read it.
-fn biome_functions(
-    pack_root: &std::path::Path,
-    modifiers: &[(bool, horizon_polytone::Targets, String)],
-) -> Vec<(&'static [Tint], crate::environment::Colormap)> {
-    use crate::environment::Colormap;
-    use horizon_polytone::colors::BiomeColor;
-    const FUNCTIONS: [(&str, &str, &[Tint]); 4] = [
-        (
-            "grass",
-            "minecraft:grass_block",
-            &[
-                Tint::Grass,
-                Tint::GrassBlock,
-                Tint::TallGrassUpper,
-                Tint::SugarCane,
-            ],
-        ),
-        ("foliage", "minecraft:oak_leaves", &[Tint::Foliage]),
-        ("dry_foliage", "minecraft:leaf_litter", &[Tint::DryFoliage]),
-        ("water", "minecraft:water", &[Tint::Water]),
-    ];
-    let colors = horizon_polytone::colors::PackColors::read(pack_root);
-    FUNCTIONS
-        .into_iter()
-        .filter_map(|(function, block, tints)| {
-            let colormap = match colors.biome_color(function) {
-                Some(BiomeColor::Flat(rgb)) => Some(Colormap::flat(rgb)),
-                Some(BiomeColor::Colormap(id)) => Colormap::load(pack_root, &id),
-                None => modifiers
-                    .iter()
-                    .find(|(fluid, targets, _)| {
-                        *fluid == (function == "water") && targets.matches(block, |_| false)
-                    })
-                    .and_then(|(_, _, id)| Colormap::load(pack_root, id)),
-            }?;
-            Some((tints, colormap))
-        })
-        .collect()
-}
 fn stem_color(age: u8) -> u32 {
    let a = u32::from(age);
    (a * 32) << 16 | (255 - a * 8) << 8 | (a * 4)
@@ -988,8 +945,7 @@ impl MeshTables {
    }
    /// These tables with the colormaps of the Polytone block and fluid modifiers of the packs
    /// merged at `pack_root` (wiki "Colormaps"): a tinted block they target takes its colour
-    /// from the colormap, and its own tint where the colormap's pixel is transparent. Vanilla's
-    /// four biome colour functions take the packs' `biome_colors` first (wiki "Custom Colors").
+    /// from the colormap, and its own tint where the colormap's pixel is transparent.
    #[must_use]
    pub fn with_polytone_colormaps(
        mut self,
@@ -997,8 +953,7 @@ impl MeshTables {
        registry: &horizon_world::registry::BlockRegistry,
    ) -> Self {
        let modifiers = crate::environment::polytone_colormap_modifiers(pack_root);
-        let biome_functions = biome_functions(pack_root, &modifiers);
-        if modifiers.is_empty() && biome_functions.is_empty() {
+        if modifiers.is_empty() {
            return self;
        }
        let mut loaded: std::collections::HashMap<String, Option<u16>> = Default::default();
@@ -1009,24 +964,7 @@ impl MeshTables {
                Some((colormaps.len() - 1) as u16)
            })
        };
-        for (tints, colormap) in biome_functions {
-            self.colormaps.push(Arc::new(colormap));
-            let i = Some((self.colormaps.len() - 1) as u16);
-            if tints == [Tint::Water] {
-                self.water_colormap = i;
-            }
-            for info in &mut self.info {
-                let own = &info.tints[..usize::from(info.tint_count).min(2)];
-                if own.iter().any(|t| tints.contains(t)) {
-                    info.colormap = i;
-                }
-            }
-        }
-        let water_function = self.water_colormap;
        for (fluid, targets, id) in &modifiers {
-            if *fluid && water_function.is_some() {
-                continue;
-            }
            if *fluid {
                if targets.matches("minecraft:water", |_| false) {
                    self.water_colormap = index(id, &mut self.colormaps);
@@ -1557,9 +1495,9 @@ struct Tints<'a> {
    /// by colormap and section-local block.
    colormaps: &'a [Arc<crate::environment::Colormap>],
    water_colormap: Option<u16>,
-    sampled: crate::fast_hash::FxHashMap<(u16, [i32; 3]), Option<u32>>,
+    sampled: std::collections::HashMap<(u16, [i32; 3]), Option<u32>>,
    /// Each colormap's own colour by block, before the blend averages them.
-    cells: crate::fast_hash::FxHashMap<(u16, [i32; 3]), Option<u32>>,
+    cells: std::collections::HashMap<(u16, [i32; 3]), Option<u32>>,
 }
 impl<'a> Tints<'a> {
    fn new(
@@ -1580,8 +1518,8 @@ impl<'a> Tints<'a> {
            uniform: None,
            colormaps: &[],
            water_colormap: None,
-            sampled: Default::default(),
-            cells: Default::default(),
+            sampled: std::collections::HashMap::new(),
+            cells: std::collections::HashMap::new(),
        }
    }
    /// With the packs' colormaps of `tables`.
@@ -1593,16 +1531,10 @@ impl<'a> Tints<'a> {
    /// Colormap `index`'s colour at block `(x, y, z)` (section-local), `None` where its pixel
    /// is transparent.
    fn colormap(&mut self, index: u16, x: i32, y: i32, z: i32) -> Option<u32> {
-        let colormap = self.colormaps.get(usize::from(index))?.clone();
-        // A colormap that ignores the height, over one biome: one colour per column.
-        let y = if colormap.column && self.uniform_biome().is_some() {
-            0
-        } else {
-            y
-        };
        if let Some(&known) = self.sampled.get(&(index, [x, y, z])) {
            return known;
        }
+        let colormap = self.colormaps.get(usize::from(index))?.clone();
        // ClientLevel.calculateBlockTint: the mean of the (2r+1)^2 colours around the block, each
        // channel summed and divided. A transparent pixel in the square leaves the block's own.
        let r = if colormap.biome_blend { self.radius } else { 0 };
@@ -1641,11 +1573,7 @@ impl<'a> Tints<'a> {
        if let Some(&known) = self.cells.get(&(index, at)) {
            return known;
        }
-        // One biome over the section and its blend margin: no zoom per block.
-        let id = match self.uniform_biome() {
-            Some(biome) => biome,
-            None => Self::biome_id(&self.zoom, self.region, self.plains, self.origin, at),
-        };
+        let id = Self::biome_id(&self.zoom, self.region, self.plains, self.origin, at);
        let [cx, cz, base_y] = self.origin;
        let block = [cx * 16 + at[0], base_y + at[1], cz * 16 + at[2]];
        let mut host = crate::environment::BlockHost::new(block, self.biomes.get(id));
@@ -251,117 +251,3 @@ fn a_biome_colormap_blends_over_a_biome_edge_as_the_vanilla_water_tint_does() {
    }
    assert!(edge_differs, "the square must cross the edge somewhere");
 }
-
-#[test]
-fn biome_colors_and_a_grass_block_colormap_replace_their_whole_biome_function() {
-    let biomes = Biomes::from_jsons(&[(
-        "minecraft:plains",
-        serde_json::json!({"effects": {"water_color": 0x3F76E4}}),
-    )]);
-    // biome_colors gives water a flat green; a block modifier colours oak leaves with a map,
-    // which Polytone spreads to the whole foliage function.
-    let root = pack(&[
-        (
-            "assets/mypack/polytone/colors.json",
-            br#"{"biome_colors": {"water": "0x00ff00"}}"#.to_vec(),
-        ),
-        (
-            "assets/mypack/polytone/colormaps/leaves.png",
-            png_row(&[[0, 0, 255, 255]]),
-        ),
-        (
-            "assets/mypack/polytone/block_modifiers/oak.json",
-            br#"{"targets": ["minecraft:oak_leaves"], "colormap": "mypack:leaves"}"#.to_vec(),
-        ),
-    ]);
-    let modifiers = crate::environment::polytone_colormap_modifiers(&root);
-    let functions = biome_functions(&root, &modifiers);
-    let tints: Vec<_> = functions.iter().map(|(t, _)| *t).collect();
-    assert_eq!(tints.len(), 2);
-    assert!(tints[0] == [Tint::Foliage] && tints[1] == [Tint::Water]);
-    let colormaps: Vec<_> = functions.into_iter().map(|(_, c)| Arc::new(c)).collect();
-    let chunks: Vec<Vec<Chunk>> = (0..3)
-        .map(|rz| (0..3).map(|rx| filled(rx - 1, rz - 1, 0)).collect())
-        .collect();
-    let region: [[Option<&Chunk>; 3]; 3] =
-        std::array::from_fn(|rz| std::array::from_fn(|rx| Some(&chunks[rz][rx])));
-    let mut tints = Tints::new(&region, &biomes, BiomeZoom::new(0), 0, [0, 0, 64]);
-    tints.colormaps = &colormaps;
-    tints.water_colormap = Some(1);
-    assert_eq!(tints.water(3, 4, 5), 0x00_FF00);
-    std::fs::remove_dir_all(root).unwrap();
-}
-
-#[test]
-fn only_a_colormap_that_ignores_the_height_is_shared_up_a_column() {
-    let root = pack(&[
-        (
-            "assets/mypack/polytone/colormaps/flat.png",
-            png_row(&[[1, 2, 3, 255]]),
-        ),
-        (
-            "assets/mypack/polytone/colormaps/flat.json",
-            br#"{"x_axis": "biome_id", "y_axis": "r.noise(o.x/60, o.z/60)"}"#.to_vec(),
-        ),
-        (
-            "assets/mypack/polytone/colormaps/tall.png",
-            png_row(&[[1, 2, 3, 255]]),
-        ),
-        (
-            "assets/mypack/polytone/colormaps/tall.json",
-            br#"{"y_axis": "y_level"}"#.to_vec(),
-        ),
-    ]);
-    let load = |id| crate::environment::Colormap::load(&root, id).unwrap();
-    assert!(load("mypack:flat").column);
-    assert!(!load("mypack:tall").column);
-    std::fs::remove_dir_all(root).unwrap();
-}
-
-/// Times a section's colormap tints with the freepack's kind of grass colormap (a biome id
-/// column and a noise row) over the default Biome Blend: `cargo test --release ... -- --ignored
-/// --nocapture colormap_tint_cost`.
-#[test]
-#[ignore = "timing, not a check"]
-fn colormap_tint_cost() {
-    const RADIUS: i32 = 2;
-    const LAYERS: i32 = 16;
-    let biomes = Biomes::from_jsons(&[(
-        "minecraft:plains",
-        serde_json::json!({"effects": {"water_color": 0x3F76E4}}),
-    )]);
-    let pixels: Vec<[u8; 4]> = (0..16).map(|i| [i * 16, 200, 64, 255]).collect();
-    let root = pack(&[
-        ("assets/mypack/polytone/colormaps/grass.png", png_row(&pixels)),
-        (
-            "assets/mypack/polytone/colormaps/grass.json",
-            br#"{"x_axis": "biome_id", "y_axis": "0.5+(r.noise(o.x/60,5+o.z/60)*0.55)", "biome_id_mapper": {"minecraft:plains": 1, "texture_size": 16}}"#
-                .to_vec(),
-        ),
-    ]);
-    let colormaps = vec![Arc::new(
-        crate::environment::Colormap::load(&root, "mypack:grass").unwrap(),
-    )];
-    let chunks: Vec<Vec<Chunk>> = (0..3)
-        .map(|rz| (0..3).map(|rx| filled(rx - 1, rz - 1, 0)).collect())
-        .collect();
-    let region: [[Option<&Chunk>; 3]; 3] =
-        std::array::from_fn(|rz| std::array::from_fn(|rx| Some(&chunks[rz][rx])));
-    let rounds = 50;
-    let start = std::time::Instant::now();
-    let mut check = 0u64;
-    for _ in 0..rounds {
-        let mut tints = Tints::new(&region, &biomes, BiomeZoom::new(0), RADIUS, [0, 0, 64]);
-        tints.colormaps = &colormaps;
-        for y in 0..LAYERS {
-            for z in 0..16 {
-                for x in 0..16 {
-                    check += u64::from(tints.colormap(0, x, y, z).unwrap_or(0));
-                }
-            }
-        }
-    }
-    let per = start.elapsed() / rounds;
-    println!("{LAYERS} layers of 256 blended colormap tints: {per:?} (checksum {check})");
-    std::fs::remove_dir_all(root).unwrap();
-}
@@ -8,7 +8,6 @@ pub use crate::settings::Opt;

 use crate::{
    gamepad::{self, GlyphStyle},
-    hdr_calibration::Picture,
    hud::{HudAtlas, HudBatch, rgba},
    keybinds::{self, CATEGORIES, KeyBinds, all_mappings},
    lang::{self, LanguageInfo},
@@ -339,7 +338,6 @@ impl Opt {
            Opt::SharePresence => "options.sharePresence",
            Opt::DirectionalAudio => "options.directionalAudio",
            Opt::MusicToast => "options.musicToast",
-            Opt::Page(page, row) => pages::slider_caption(page, row),
        }
    }
    pub(crate) fn kind(self, s: &Settings) -> Kind {
@@ -403,7 +401,6 @@ impl Opt {
            Opt::PadLookDeadzone => unit(s.controller.look_deadzone, 0.0, 0.5),
            Opt::PadTriggerThreshold => unit(s.controller.trigger_threshold, 0.1, 0.9),
            Opt::SprintWindow => unit(s.sprint_window as f32, 0.0, 10.0),
-            Opt::Page(page, row) => pages::slider_kind(page, row),
            _ => Kind::Cycle,
        }
    }
@@ -880,7 +877,6 @@ impl Opt {
                gamepad::TextKeyboard::Horizon => "horizon.options.keyboard.horizon",
                gamepad::TextKeyboard::Steam => "horizon.options.keyboard.steam",
            }),
-            Opt::Page(page, row) => pages::slider_text(page, row),
            _ => Text::empty(),
        }
    }
@@ -955,7 +951,6 @@ impl Opt {
            Opt::PadLookDeadzone => s.controller.look_deadzone = step(0.0, 50.0) / 100.0,
            Opt::PadTriggerThreshold => s.controller.trigger_threshold = step(10.0, 90.0) / 100.0,
            Opt::SprintWindow => s.sprint_window = step(0.0, 10.0) as i32,
-            Opt::Page(page, row) => pages::slide(page, row, v),
            _ => {}
        }
        if self.affects_preset() {
@@ -1335,8 +1330,6 @@ pub enum Page {
    ModProject,
    /// A native mod's settings page: its index in `mods.installed`.
    NativeMod(usize),
-    /// A page a crate registered (`horizon_hooks::pages`): its index in `OptionsUi::pages`.
-    Added(usize),
    /// Horizon's shader packs, either kind (`shader_pack_list`).
    ShaderPacks,
    /// The picked pack's options: the shader screen (`shader_ui`) at the pack's main screen.
@@ -1396,8 +1389,6 @@ enum Act {
    /// A native mod's key (mod, key) waits for a key; a button of its page.
    NativeKey(usize, usize),
    NativeButton(usize, usize),
-    /// A registered page's row: (page, row).
-    PageRow(usize, usize),
    OpenModFolder,
    /// Browse mods: the page of listing `.0` of `mod_browser`.
    ModProject(usize),
@@ -1625,8 +1616,7 @@ pub struct OptionsUi {
    /// Key Binds: the mapping waiting for a key ([`NATIVE_KEY`]: a native
    /// mod's, `selected_native_key`).
    pub selected_key: Option<&'static str>,
-    /// The native mod's key waiting: (mod, key) in `mods.installed`, or a registered page's
-    /// (page, row) ([`pages::PAGE_KEY`]).
+    /// The native mod's key waiting: (mod, key) in `mods.installed`.
    selected_native_key: Option<(usize, usize)>,
    /// Bindings: the action waiting for a pad button.
    pub selected_pad_action: Option<&'static str>,
@@ -1692,8 +1682,8 @@ pub struct OptionsUi {
    pub split_profiles: crate::split_profiles::SplitProfiles,
    /// HDR calibration while its page is open.
    pub calibration: Option<crate::hdr_calibration::Calibration>,
-    /// The window as calibration found it before making it fullscreen (the game keeps it).
-    pub calibration_window: Option<crate::hdr_calibration::WindowState>,
+    /// Whether the window was fullscreen before calibration made it so (the game keeps it).
+    pub calibration_fullscreen: Option<bool>,
    pub split_setup: crate::split_ui::SplitUi,
    pub studio: crate::studio_ui::StudioUi,
    /// The AI Agent page's status lines (set by the game while it shows).
@@ -1772,7 +1762,7 @@ impl Default for OptionsUi {
            pack_configs: Default::default(),
            split_profiles: Default::default(),
            calibration: None,
-            calibration_window: None,
+            calibration_fullscreen: None,
            split_setup: Default::default(),
            studio: Default::default(),
            agent_status: Vec::new(),
@@ -1870,6 +1860,25 @@ fn wide_extras(s: &Settings, width: impl Fn(&str) -> f32) -> Vec<crate::extras::
        })
        .collect()
 }
+/// What a button opening one of Horizon's pages says on hover.
+fn horizon_page_tooltip(page: Page) -> Option<&'static str> {
+    Some(match page {
+        Page::Horizon => "horizon.pages.settings.tooltip",
+        Page::Studio => "horizon.pages.studio.tooltip",
+        Page::Graphics => "horizon.pages.graphics.tooltip",
+        Page::GraphicsAdvanced => "horizon.pages.graphics_advanced.tooltip",
+        Page::Controller => "horizon.pages.controller.tooltip",
+        Page::Extras => "horizon.pages.extras.tooltip",
+        Page::Pvp => "horizon.pages.pvp.tooltip",
+        Page::Agent => "horizon.pages.agent.tooltip",
+        Page::SplitProfiles => "horizon.pages.split_profiles.tooltip",
+        Page::ShaderPacks => "horizon.pages.shader_packs.tooltip",
+        Page::Mods => "horizon.pages.mods.tooltip",
+        Page::SplitSetup => "horizon.pages.split_setup.tooltip",
+        Page::Music => "horizon.pages.music.tooltip",
+        _ => return None,
+    })
+}
 /// Rows of an OptionsList: (big?, options) or a header.
 enum Row {
    Big(Opt),
@@ -1889,17 +1898,14 @@ fn tooltip_text(s: &Settings, wd: &Widget) -> Option<Text> {
            return None;
        };
        let key = opt.tooltip_key(s);
-        let Opt::Page(page, row) = opt else {
-            return lang::has(&key).then(|| tr(&key));
-        };
-        return pages::tooltip(*page, *row);
+        return lang::has(&key).then(|| tr(&key));
    };
    let mut tip = None;
    if let Act::Extra(item) = act {
        tip = Some(Text::literal(item.description_text()));
    }
    if let Act::Push(page) = act
-        && let Some(text) = pages::horizon_page_tooltip(*page)
+        && let Some(text) = horizon_page_tooltip(*page)
    {
        tip = Some(tr(text));
    }
@@ -1919,7 +1925,6 @@ fn tooltip_text(s: &Settings, wd: &Widget) -> Option<Text> {
    }
    match act {
        Act::Cycle(opt) if !opt.available() => Some(tr("horizon.options.unavailable")),
-        Act::PageRow(page, row) => pages::tooltip(*page, *row),
        Act::ToggleMod(i) => match s.mods.installed.get(*i) {
            Some(installed) => {
                let description = installed
@@ -2361,7 +2366,6 @@ impl OptionsUi {
            Page::ModBrowser => "horizon.mods.browse.title",
            Page::ModProject => "horizon.mods.browse.project",
            Page::NativeMod(_) => "Mod Settings",
-            Page::Added(i) => pages::title(i),
            Page::ShaderPacks => "horizon.pages.shader_packs",
            Page::ShaderOptions => "horizon.pages.shader_options",
            Page::PackOptions => "horizon.pack.options.title",
@@ -2578,6 +2582,43 @@ impl OptionsUi {
        }
        rows
    }
+    /// A native mod's page: its name, its keys as Key Binds rows (the
+    /// player's choice, else the default), then its buttons.
+    fn native_rows(&self, s: &Settings, i: usize) -> Vec<Row> {
+        let Some(m) = s.mods.installed.get(i) else {
+            return Vec::new();
+        };
+        let mut rows = vec![Row::Note(m.title.clone())];
+        let Some(page) = &m.native else {
+            return rows;
+        };
+        let chosen = s.mods.keys.get(&m.id);
+        for (k, [name, label, default]) in page.keys.iter().enumerate() {
+            let key = chosen.and_then(|c| c.get(name)).unwrap_or(default);
+            let mut message = keybinds::display_name(key);
+            if self.selected_native_key == Some((i, k)) {
+                message = Text::literal("> ")
+                    .append(message.with_color(text::WHITE))
+                    .append(" <")
+                    .with_color(text::YELLOW);
+            }
+            let caption = button(0.0, 0.0, 150.0, Text::literal(label.clone()), Act::None);
+            let change = button(0.0, 0.0, 150.0, message, Act::NativeKey(i, k));
+            rows.push(Row::Buttons(inactive(caption), Some(change)));
+        }
+        for (b, label) in page.buttons.iter().enumerate() {
+            let widget = button(
+                0.0,
+                0.0,
+                310.0,
+                Text::literal(label.clone()),
+                Act::NativeButton(i, b),
+            );
+            rows.push(Row::Buttons(widget, None));
+        }
+        rows
+    }
+
    fn list_rows(&self, s: &Settings) -> Vec<Row> {
        match self.page() {
            Page::SplitSetup => Vec::new(),
@@ -2642,7 +2683,47 @@ impl OptionsUi {
                flush(&mut rows, &mut section);
                rows
            }
-            Page::Horizon => self.horizon_rows(s),
+            Page::Horizon => {
+                // Two to a row, as vanilla's OptionsList.addSmall lays out
+                // buttons; each opens one of Horizon's settings pages. Each page has
+                // one way in: graphics and shader packs are Video Settings' (the graphics
+                // screen), the controller is Controls', mods are the Options screen's.
+                let open =
+                    |key: &str, page: Page| button(0.0, 0.0, 150.0, tr(key), Act::Push(page));
+                vec![
+                    Row::Buttons(
+                        open("horizon.pages.open.extras", Page::Extras),
+                        Some(open("horizon.pages.open.pvp", Page::Pvp)),
+                    ),
+                    Row::Buttons(
+                        open(
+                            "horizon.pages.open.split_setup",
+                            if self.split_guest {
+                                Page::SplitProfiles
+                            } else {
+                                Page::SplitSetup
+                            },
+                        ),
+                        Some(open("horizon.pages.open.studio", Page::Studio)),
+                    ),
+                    // No AI hides the AI Agent page and everything AI.
+                    Row::Buttons(
+                        self.extra_button(s, crate::extras::Item::DiscordPresence),
+                        Some(if s.extras.no_ai {
+                            self.extra_button(s, crate::extras::Item::NoAi)
+                        } else {
+                            open("horizon.pages.open.agent", Page::Agent)
+                        }),
+                    ),
+                ]
+                .into_iter()
+                .chain(
+                    (!s.extras.no_ai).then(|| {
+                        Row::Buttons(self.extra_button(s, crate::extras::Item::NoAi), None)
+                    }),
+                )
+                .collect()
+            }
            Page::Agent => {
                let mut rows = vec![Row::Buttons(
                    self.extra_button(s, crate::extras::Item::AgentControl),
@@ -2925,7 +3006,6 @@ impl OptionsUi {
            Page::ModBrowser => self.mod_browser_rows(),
            Page::ModProject => self.mod_project_rows(s),
            Page::NativeMod(i) => self.native_rows(s, i),
-            Page::Added(i) => self.added_rows(i),
            _ => {
                let _ = s;
                Vec::new()
@@ -3950,7 +4030,7 @@ impl OptionsUi {
            if right {
                return Vec::new();
            }
-            let outcome = c.click(&atlas.font, (x, y), size, drag);
+            let outcome = c.click((x, y), size, drag);
            return self.calibration_outcome(s, outcome);
        }
        if self.shell().is_some() {
@@ -4192,9 +4272,11 @@ impl OptionsUi {
                            self.push(Page::NativeMod(i));
                            events.push(Event::NativeSettings(i));
                        }
-                        Act::NativeKey(i, k) => self.wait_native_key(i, k),
+                        Act::NativeKey(i, k) => {
+                            self.selected_key = Some(NATIVE_KEY);
+                            self.selected_native_key = Some((i, k));
+                        }
                        Act::NativeButton(i, b) => events.push(Event::NativeButton(i, b)),
-                        Act::PageRow(p, r) => events.extend(self.page_act(p, r, self.shift)),
                        Act::OpenModFolder => events.push(Event::OpenModFolder),
                        Act::ModProject(i) => {
                            if let Some(listing) = self.mod_browser.listings.get(i) {
@@ -4550,12 +4632,13 @@ impl OptionsUi {
            }
        }
    }
-    /// HDR calibration's test picture, while its page is open, in a GUI of `size`.
-    pub fn calibration_picture(&self, atlas: &HudAtlas, size: (f32, f32)) -> Option<Picture> {
+    /// HDR calibration's test picture, while its page is open: the step, its nits and
+    /// where the controls start (a share of the height `h`).
+    pub fn calibration_picture(&self, h: f32) -> Option<(crate::hdr_calibration::Step, f32, f32)> {
        self.calibration
            .as_ref()
            .filter(|_| self.page() == Page::HdrCalibration)
-            .map(|c| c.picture(&atlas.font, size))
+            .map(|c| c.picture(h))
    }
    pub fn back(&mut self, s: &mut Settings) -> Vec<Event> {
        let mut events = Vec::new();
@@ -4698,10 +4781,19 @@ impl OptionsUi {
        let Some(name) = self.selected_key.take() else {
            return Vec::new();
        };
-        if name == NATIVE_KEY || name == pages::PAGE_KEY {
-            return self.bind_native_key(s, name, value);
+        if name == NATIVE_KEY {
+            let (i, k) = self.selected_native_key.take().unwrap_or_default();
+            let Some(m) = s.mods.installed.get(i) else {
+                return Vec::new();
+            };
+            let Some([key, ..]) = m.native.as_ref().and_then(|p| p.keys.get(k)) else {
+                return Vec::new();
+            };
+            let keys = s.mods.keys.entry(m.id.clone()).or_default();
+            keys.insert(key.clone(), value);
+            return vec![Event::Changed];
        }
-        if !s.extras.set_key(name, value.clone()) {
+        if !s.extras.set_key(name, value.clone()) && !s.horizon.set_key(name, value.clone()) {
            s.keys.set(name, &value);
        }
        vec![Event::Changed]
@@ -5081,9 +5173,11 @@ impl OptionsUi {
                            self.push(Page::NativeMod(i));
                            events.push(Event::NativeSettings(i));
                        }
-                        Act::NativeKey(i, k) => self.wait_native_key(i, k),
+                        Act::NativeKey(i, k) => {
+                            self.selected_key = Some(NATIVE_KEY);
+                            self.selected_native_key = Some((i, k));
+                        }
                        Act::NativeButton(i, b) => events.push(Event::NativeButton(i, b)),
-                        Act::PageRow(p, r) => events.extend(self.page_act(p, r, shift)),
                        Act::OpenModFolder => events.push(Event::OpenModFolder),
                        Act::ModProject(i) => {
                            if let Some(listing) = self.mod_browser.listings.get(i) {
@@ -7254,7 +7348,7 @@ mod tests {
            MouseButton::Back,
            MouseButton::Forward,
        ] {
-            for name in [SORT_KEY, "key.jump"] {
+            for name in [SORT_KEY, crate::graphics::HDR_KEY, "key.jump"] {
                let mut ui = OptionsUi::default();
                let mut s = Settings::default();
                ui.selected_key = Some(name);
@@ -7263,6 +7357,7 @@ mod tests {
                let value = keybinds::mouse_name(button);
                match name {
                    SORT_KEY => assert_eq!(s.extras.sort_key, value),
+                    crate::graphics::HDR_KEY => assert_eq!(s.horizon.hdr_key, value),
                    _ => assert_eq!(s.keys.get(name), value),
                }
                assert_eq!(Extras::parse(&s.extras.serialize()), s.extras);
@@ -8344,5 +8439,3 @@ mod tests {
 #[cfg(test)]
 #[path = "options_ui_graphics_tests.rs"]
 mod graphics_tests;
-#[path = "options_ui_pages.rs"]
-mod pages;
@@ -143,34 +143,3 @@ fn the_graphics_screens_wheel_scrolls_even_over_a_slider_being_changed() {
    assert_eq!(s.horizon.chunk_updates, 16);
    assert!(ui.graphics.scroll_amount() > before);
 }
-
-/// A window holding HDR output back (a start failed on its driver) shows it on the HDR page
-/// as soon as the graphics screen opens, with no setting applied: the row's line, and
-/// Calibrate blocked, where the same window not holding it back calibrates.
-#[test]
-fn a_held_hdr_start_shows_as_the_graphics_screen_opens() {
-    use crate::gfx::output::tests::{snapshot, window};
-    let atlas = atlas();
-    let mut s = Settings::default();
-    s.horizon.hdr = crate::graphics::HdrMode::Auto;
-    s.horizon.hdr_failed_start = Some("Vulkan 10de:2684 GPU; driver; 1.0; os".into());
-    let (mut caps, reading) = window(Some(crate::gfx::HdrOutput::Pq), Some(true));
-    for held in [true, false] {
-        caps.held = held;
-        let mut ui = OptionsUi {
-            size: (427.0, 240.0),
-            ..Default::default()
-        };
-        let output = snapshot(&s.horizon, Default::default(), caps, reading);
-        ui.draw(
-            &s,
-            output,
-            &mut HudBatch::new([427, 240]),
-            &atlas,
-            (-1.0, -1.0),
-        );
-        ui.show(Page::Graphics);
-        assert!(calibrates(&mut ui, &mut s, &atlas) != held, "held {held}");
-        assert_eq!(ui.graphics.screen.output.held, held);
-    }
-}
@@ -1,464 +0,0 @@
-//! The pages crates add to the options screens: a native mod's settings page (its keys and
-//! buttons), and the pages crates above the engine register (`horizon_hooks::pages`, docs/layers.md
-//! "Platform registries") with their entries on Horizon Settings. Kept out of options_ui.rs, which
-//! may not grow (tools/check_file_size.py).
-use super::*;
-use horizon_hooks::pages as added;
-
-/// `selected_key` while a registered page's key waits (`selected_native_key`: page, row).
-pub(super) const PAGE_KEY: &str = "horizon.pageKey";
-
-#[cfg(test)]
-thread_local! {
-    /// A test's own pages, instead of the game's registered ones: each test runs on its thread.
-    static TEST_PAGES: std::cell::Cell<Option<&'static [&'static dyn added::Page]>> =
-        const { std::cell::Cell::new(None) };
-}
-
-/// The pages crates registered.
-fn registered() -> &'static [&'static dyn added::Page] {
-    #[cfg(test)]
-    if let Some(pages) = TEST_PAGES.get() {
-        return pages;
-    }
-    added::engine::all()
-}
-
-/// A registered page's title (a translation key).
-pub(super) fn title(page: usize) -> &'static str {
-    registered().get(page).map_or("", |p| p.title())
-}
-
-/// Row `r` of a registered page, as it is now.
-fn row(page: usize, r: usize) -> Option<added::Row> {
-    let mut rows = Vec::new();
-    registered().get(page)?.rows(&mut rows);
-    rows.into_iter().nth(r)
-}
-
-/// A registered page's slider ([`Opt::Page`]): its caption (a translation key).
-pub(super) fn slider_caption(page: usize, r: usize) -> &'static str {
-    match row(page, r) {
-        Some(added::Row::Slider { label, .. }) => label,
-        _ => "",
-    }
-}
-
-/// A registered page's slider: its position.
-pub(super) fn slider_kind(page: usize, r: usize) -> Kind {
-    match row(page, r) {
-        Some(added::Row::Slider { value, .. }) => Kind::Slider(value.clamp(0.0, 1.0)),
-        _ => Kind::Cycle,
-    }
-}
-
-/// A registered page's slider: the value its message shows after the caption.
-pub(super) fn slider_text(page: usize, r: usize) -> Text {
-    match row(page, r) {
-        Some(added::Row::Slider { text, .. }) => label_text(text),
-        _ => Text::empty(),
-    }
-}
-
-/// A registered page's slider moved.
-pub(super) fn slide(page: usize, r: usize, value: f32) {
-    if let Some(registered) = registered().get(page) {
-        registered.act(r, added::Act::Slide(value));
-    }
-}
-
-/// What a registered page's row says on hover.
-pub(super) fn tooltip(page: usize, r: usize) -> Option<Text> {
-    registered().get(page)?.tooltip(r).map(label_text)
-}
-
-/// What a button opening one of Horizon's pages says on hover.
-pub(super) fn horizon_page_tooltip(page: Page) -> Option<&'static str> {
-    Some(match page {
-        Page::Horizon => "horizon.pages.settings.tooltip",
-        Page::Studio => "horizon.pages.studio.tooltip",
-        Page::Graphics => "horizon.pages.graphics.tooltip",
-        Page::GraphicsAdvanced => "horizon.pages.graphics_advanced.tooltip",
-        Page::Controller => "horizon.pages.controller.tooltip",
-        Page::Extras => "horizon.pages.extras.tooltip",
-        Page::Pvp => "horizon.pages.pvp.tooltip",
-        Page::Agent => "horizon.pages.agent.tooltip",
-        Page::SplitProfiles => "horizon.pages.split_profiles.tooltip",
-        Page::ShaderPacks => "horizon.pages.shader_packs.tooltip",
-        Page::Mods => "horizon.pages.mods.tooltip",
-        Page::SplitSetup => "horizon.pages.split_setup.tooltip",
-        Page::Music => "horizon.pages.music.tooltip",
-        _ => return None,
-    })
-}
-
-fn label_text(label: added::Label) -> Text {
-    match label {
-        added::Label::Key(key) => tr(key),
-        added::Label::Value(value) => Text::literal(value),
-    }
-}
-
-impl OptionsUi {
-    /// Horizon Settings: its pages, then the pages crates registered for it.
-    pub(super) fn horizon_rows(&self, s: &Settings) -> Vec<Row> {
-        // Two to a row, as vanilla's OptionsList.addSmall lays out
-        // buttons; each opens one of Horizon's settings pages. Each page has
-        // one way in: graphics and shader packs are Video Settings' (the graphics
-        // screen), the controller is Controls', mods are the Options screen's.
-        let open = |key: &str, page: Page| button(0.0, 0.0, 150.0, tr(key), Act::Push(page));
-        let mut rows: Vec<Row> = vec![
-            Row::Buttons(
-                open("horizon.pages.open.extras", Page::Extras),
-                Some(open("horizon.pages.open.pvp", Page::Pvp)),
-            ),
-            Row::Buttons(
-                open(
-                    "horizon.pages.open.split_setup",
-                    if self.split_guest {
-                        Page::SplitProfiles
-                    } else {
-                        Page::SplitSetup
-                    },
-                ),
-                Some(open("horizon.pages.open.studio", Page::Studio)),
-            ),
-            // No AI hides the AI Agent page and everything AI.
-            Row::Buttons(
-                self.extra_button(s, crate::extras::Item::DiscordPresence),
-                Some(if s.extras.no_ai {
-                    self.extra_button(s, crate::extras::Item::NoAi)
-                } else {
-                    open("horizon.pages.open.agent", Page::Agent)
-                }),
-            ),
-        ]
-        .into_iter()
-        .chain(
-            (!s.extras.no_ai)
-                .then(|| Row::Buttons(self.extra_button(s, crate::extras::Item::NoAi), None)),
-        )
-        .collect();
-        self.added_entries(&mut rows);
-        rows
-    }
-
-    /// The entries of the pages registered for Horizon Settings, two to a row like the engine's.
-    fn added_entries(&self, rows: &mut Vec<Row>) {
-        let mut entries = registered()
-            .iter()
-            .enumerate()
-            .filter(|(_, page)| page.place() == added::Place::HorizonSettings)
-            .map(|(i, page)| button(0.0, 0.0, 150.0, tr(page.title()), Act::Push(Page::Added(i))));
-        while let Some(first) = entries.next() {
-            rows.push(Row::Buttons(first, entries.next()));
-        }
-    }
-
-    /// A registered page's rows, asked of it each time the page is drawn.
-    pub(super) fn added_rows(&self, page: usize) -> Vec<Row> {
-        let Some(registered) = registered().get(page) else {
-            return Vec::new();
-        };
-        let mut rows = Vec::new();
-        registered.rows(&mut rows);
-        rows.into_iter()
-            .enumerate()
-            .map(|(r, row)| self.added_row(page, r, row))
-            .collect()
-    }
-
-    fn added_row(&self, page: usize, r: usize, row: added::Row) -> Row {
-        let act = Act::PageRow(page, r);
-        let wide = |label: Text| Row::Buttons(button(0.0, 0.0, 310.0, label, act.clone()), None);
-        match row {
-            added::Row::Heading(key) => Row::Heading(key.to_owned()),
-            added::Row::Note(text) => Row::Note(text),
-            added::Row::Toggle { label, on } => wide(generic(label, on_off(on))),
-            added::Row::Cycle { label, value } => wide(generic(label, label_text(value))),
-            added::Row::Slider { .. } => Row::Big(Opt::Page(page, r)),
-            added::Row::Button { label } => wide(tr(label)),
-            added::Row::Key { label, key } => {
-                let mut message = keybinds::display_name(&key);
-                if self.selected_key == Some(PAGE_KEY)
-                    && self.selected_native_key == Some((page, r))
-                {
-                    message = Text::literal("> ")
-                        .append(message.with_color(text::WHITE))
-                        .append(" <")
-                        .with_color(text::YELLOW);
-                }
-                let caption = button(0.0, 0.0, 150.0, tr(label), Act::None);
-                let change = button(0.0, 0.0, 150.0, message, act);
-                Row::Buttons(inactive(caption), Some(change))
-            }
-            // A row kind newer than this engine: shown empty.
-            _ => Row::Note(String::new()),
-        }
-    }
-
-    /// A registered page's row was pressed: a key row waits for a key, any other row hears it.
-    pub(super) fn page_act(&mut self, page: usize, r: usize, shift: bool) -> Vec<Event> {
-        let Some(registered) = registered().get(page) else {
-            return Vec::new();
-        };
-        let mut rows = Vec::new();
-        registered.rows(&mut rows);
-        match rows.get(r) {
-            Some(added::Row::Key { .. }) => {
-                self.selected_key = Some(PAGE_KEY);
-                self.selected_native_key = Some((page, r));
-                Vec::new()
-            }
-            Some(_) => {
-                registered.act(
-                    r,
-                    if shift {
-                        added::Act::PressBack
-                    } else {
-                        added::Act::Press
-                    },
-                );
-                vec![Event::Changed]
-            }
-            None => Vec::new(),
-        }
-    }
-
-    /// A native mod's page: its name, its keys as Key Binds rows (the
-    /// player's choice, else the default), then its buttons.
-    pub(super) fn native_rows(&self, s: &Settings, i: usize) -> Vec<Row> {
-        let Some(m) = s.mods.installed.get(i) else {
-            return Vec::new();
-        };
-        let mut rows = vec![Row::Note(m.title.clone())];
-        let Some(page) = &m.native else {
-            return rows;
-        };
-        let chosen = s.mods.keys.get(&m.id);
-        for (k, [name, label, default]) in page.keys.iter().enumerate() {
-            let key = chosen.and_then(|c| c.get(name)).unwrap_or(default);
-            let mut message = keybinds::display_name(key);
-            if self.selected_native_key == Some((i, k)) {
-                message = Text::literal("> ")
-                    .append(message.with_color(text::WHITE))
-                    .append(" <")
-                    .with_color(text::YELLOW);
-            }
-            let caption = button(0.0, 0.0, 150.0, Text::literal(label.clone()), Act::None);
-            let change = button(0.0, 0.0, 150.0, message, Act::NativeKey(i, k));
-            rows.push(Row::Buttons(inactive(caption), Some(change)));
-        }
-        for (b, label) in page.buttons.iter().enumerate() {
-            let widget = button(
-                0.0,
-                0.0,
-                310.0,
-                Text::literal(label.clone()),
-                Act::NativeButton(i, b),
-            );
-            rows.push(Row::Buttons(widget, None));
-        }
-        rows
-    }
-
-    /// A native mod's key waits for the next key or button pressed.
-    pub(super) fn wait_native_key(&mut self, i: usize, k: usize) {
-        self.selected_key = Some(NATIVE_KEY);
-        self.selected_native_key = Some((i, k));
-    }
-
-    /// The key pressed for the native mod's key, or the registered page's ([`PAGE_KEY`]), that
-    /// waited for one.
-    pub(super) fn bind_native_key(
-        &mut self,
-        s: &mut Settings,
-        name: &str,
-        value: String,
-    ) -> Vec<Event> {
-        let (i, k) = self.selected_native_key.take().unwrap_or_default();
-        if name == PAGE_KEY {
-            if let Some(page) = registered().get(i) {
-                page.act(k, added::Act::Bind(value));
-            }
-            return vec![Event::Changed];
-        }
-        let Some(m) = s.mods.installed.get(i) else {
-            return Vec::new();
-        };
-        let Some([key, ..]) = m.native.as_ref().and_then(|p| p.keys.get(k)) else {
-            return Vec::new();
-        };
-        let keys = s.mods.keys.entry(m.id.clone()).or_default();
-        keys.insert(key.clone(), value);
-        vec![Event::Changed]
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::sync::Mutex;
-
-    /// A page with a heading, a switch, a number that steps either way, a key and a volume.
-    struct Sample {
-        on: Mutex<bool>,
-        step: Mutex<i32>,
-        key: Mutex<String>,
-        volume: Mutex<f32>,
-    }
-
-    impl added::Page for Sample {
-        fn id(&self) -> &'static str {
-            "test.sample"
-        }
-        fn title(&self) -> &'static str {
-            "test.sample.title"
-        }
-        fn place(&self) -> added::Place {
-            added::Place::HorizonSettings
-        }
-        fn rows(&self, rows: &mut Vec<added::Row>) {
-            rows.push(added::Row::Heading("test.sample.heading"));
-            rows.push(added::Row::Toggle {
-                label: "test.sample.switch",
-                on: *self.on.lock().unwrap(),
-            });
-            rows.push(added::Row::Cycle {
-                label: "test.sample.step",
-                value: added::Label::Value(self.step.lock().unwrap().to_string()),
-            });
-            rows.push(added::Row::Key {
-                label: "test.sample.key",
-                key: self.key.lock().unwrap().clone(),
-            });
-            let volume = *self.volume.lock().unwrap();
-            rows.push(added::Row::Slider {
-                label: "test.sample.volume",
-                value: volume,
-                text: added::Label::Value(format!("{}%", (volume * 100.0).round())),
-            });
-        }
-        fn act(&self, row: usize, act: added::Act) {
-            match (row, act) {
-                (1, added::Act::Press) => {
-                    let mut on = self.on.lock().unwrap();
-                    *on = !*on;
-                }
-                (2, added::Act::Press) => *self.step.lock().unwrap() += 1,
-                (2, added::Act::PressBack) => *self.step.lock().unwrap() -= 1,
-                (3, added::Act::Bind(key)) => *self.key.lock().unwrap() = key,
-                (4, added::Act::Slide(v)) => *self.volume.lock().unwrap() = v,
-                other => panic!("row and act the page doesn't expect: {other:?}"),
-            }
-        }
-        fn tooltip(&self, row: usize) -> Option<added::Label> {
-            (row == 1).then_some(added::Label::Key("test.sample.switch.tooltip"))
-        }
-    }
-
-    static SAMPLE: Sample = Sample {
-        on: Mutex::new(false),
-        step: Mutex::new(0),
-        key: Mutex::new(String::new()),
-        volume: Mutex::new(0.0),
-    };
-    static PAGES: [&dyn added::Page; 1] = [&SAMPLE];
-
-    /// Clicks the active button that does `act`, with Shift held or not.
-    fn press(ui: &mut OptionsUi, s: &mut Settings, act: Act, shift: bool) -> Vec<Event> {
-        let size = (480.0, 240.0);
-        let (widgets, ..) = ui.layout(s, size.0, size.1);
-        let (x, y) = widgets
-            .iter()
-            .find_map(|w| match &w.kind {
-                WKind::Button {
-                    act: a,
-                    active: true,
-                    ..
-                } if *a == act => Some((w.x + 1.0, w.y + 1.0)),
-                _ => None,
-            })
-            .unwrap_or_else(|| panic!("no button does {act:?}"));
-        ui.shift = shift;
-        let atlas = super::super::tests::atlas();
-        ui.click(s, &atlas, x, y, size, [480, 240], false, false)
-    }
-
-    #[test]
-    fn a_registered_page_opens_from_horizon_settings_and_hears_its_rows() {
-        let mut s = Settings::default();
-        TEST_PAGES.set(Some(&PAGES));
-        let mut ui = OptionsUi::default();
-        ui.show(Page::Horizon);
-        press(&mut ui, &mut s, Act::Push(Page::Added(0)), false);
-        assert_eq!(ui.page(), Page::Added(0));
-        // Rows: the heading (0), the switch (1), the step (2), the key (3).
-        let events = press(&mut ui, &mut s, Act::PageRow(0, 1), false);
-        assert_eq!(
-            events.last(),
-            Some(&Event::Changed),
-            "the settings get saved"
-        );
-        assert!(*SAMPLE.on.lock().unwrap());
-        press(&mut ui, &mut s, Act::PageRow(0, 2), false);
-        press(&mut ui, &mut s, Act::PageRow(0, 2), true);
-        press(&mut ui, &mut s, Act::PageRow(0, 2), true);
-        assert_eq!(*SAMPLE.step.lock().unwrap(), -1, "Shift steps back");
-        // A key row waits for the next key, as on Key Binds, and the page gets its name.
-        press(&mut ui, &mut s, Act::PageRow(0, 3), false);
-        let atlas = super::super::tests::atlas();
-        let events = ui.key(&mut s, &atlas, winit::keyboard::KeyCode::KeyZ, None);
-        assert_eq!(events, [Event::Changed]);
-        assert_eq!(*SAMPLE.key.lock().unwrap(), "key.keyboard.z");
-        assert_eq!(ui.selected_key, None);
-        // The volume is one of the screen's own sliders: dragged to its middle, then let go.
-        let size = (480.0, 240.0);
-        let (widgets, ..) = ui.layout(&s, size.0, size.1);
-        let slider = widgets
-            .iter()
-            .find(|w| {
-                matches!(
-                    w.kind,
-                    WKind::Slider {
-                        opt: Opt::Page(0, 4),
-                        ..
-                    }
-                )
-            })
-            .expect("the volume's slider");
-        let (x, y) = (slider.x + slider.w / 2.0, slider.y + 1.0);
-        ui.click(&mut s, &atlas, x, y, size, [480, 240], false, false);
-        let volume = *SAMPLE.volume.lock().unwrap();
-        assert!((0.45..0.55).contains(&volume), "{volume}");
-        assert!(ui.release().contains(&Event::Changed));
-        // The slider shows the page's value once let go.
-        let (widgets, ..) = ui.layout(&s, size.0, size.1);
-        let shown = widgets.iter().find_map(|w| match w.kind {
-            WKind::Slider {
-                opt: Opt::Page(0, 4),
-                value,
-                ..
-            } => Some(value),
-            _ => None,
-        });
-        assert_eq!(shown, Some(volume));
-        // The page's tooltip for its switch.
-        let switch = widgets
-            .iter()
-            .find(|w| {
-                matches!(
-                    &w.kind,
-                    WKind::Button {
-                        act: Act::PageRow(0, 1),
-                        ..
-                    }
-                )
-            })
-            .expect("the switch");
-        assert_eq!(
-            tooltip_text(&s, switch).map(|t| t.plain()),
-            Some(tr("test.sample.switch.tooltip").plain())
-        );
-    }
-}
@@ -1,252 +0,0 @@
-//! OptiFine custom skies (`horizon_optifine::sky`) on the engine's sky layers
-//! ([`crate::custom_sky`]): a pack's layers with their decoded textures, read once with the pack,
-//! and each frame's choice of layers, their brightness and rotation. A pack without
-//! `optifine/sky` has none, and the sky stays vanilla.
-
-use std::path::Path;
-
-use glam::{Mat4, Vec3};
-use horizon_optifine::sky::{Blend, Conditions, Now, Skies, SkyLayer, Transition};
-
-use crate::custom_sky::{self as engine, Draw, Image, SkyLayers, State};
-
-/// The pack's layers, by world, with one texture per layer (`images[i]` for the `i`th layer
-/// over all worlds, in `worlds` order).
-#[derive(Default)]
-pub struct CustomSky {
-    worlds: Vec<(i32, Vec<SkyLayer>)>,
-    pub images: Vec<Image>,
-}
-
-/// Textures past this many texels in all are left out (a skybox is a few megapixels at most).
-const TEXEL_BUDGET: u64 = 64 << 20;
-
-impl CustomSky {
-    /// The custom skies of the overlay at `root`. A layer whose texture does not decode is
-    /// dropped with a warning.
-    pub fn load(root: &Path) -> Self {
-        let skies = Skies::scan(root);
-        let mut out = Self::default();
-        let mut texels = 0u64;
-        for (world, sky) in skies.worlds {
-            let mut layers = Vec::new();
-            for layer in sky.layers {
-                match crate::hud::decode(&root.join(&layer.source)) {
-                    Ok((width, height, rgba))
-                        if texels + u64::from(width) * u64::from(height) <= TEXEL_BUDGET =>
-                    {
-                        texels += u64::from(width) * u64::from(height);
-                        out.images.push(Image {
-                            width,
-                            height,
-                            rgba,
-                        });
-                        layers.push(layer);
-                    }
-                    Ok(_) => log::warn!("{}: past the custom sky's texture budget", layer.source),
-                    Err(e) => log::warn!("{}: {e:#}", layer.source),
-                }
-            }
-            if !layers.is_empty() {
-                out.worlds.push((world, layers));
-            }
-        }
-        out
-    }
-
-    pub fn is_empty(&self) -> bool {
-        self.worlds.is_empty()
-    }
-}
-
-/// The engine's sky blend for OptiFine's.
-fn blend(blend: Blend) -> engine::Blend {
-    match blend {
-        Blend::Add => engine::Blend::Add,
-        Blend::Subtract => engine::Blend::Subtract,
-        Blend::Multiply => engine::Blend::Multiply,
-        Blend::Dodge => engine::Blend::Dodge,
-        Blend::Burn => engine::Blend::Burn,
-        Blend::Screen => engine::Blend::Screen,
-        Blend::Replace => engine::Blend::Replace,
-        Blend::Overlay => engine::Blend::Overlay,
-        Blend::Alpha => engine::Blend::Alpha,
-    }
-}
-
-impl SkyLayers for CustomSky {
-    fn images(&self) -> &[Image] {
-        &self.images
-    }
-
-    /// Whether `world` has layers (`0` the Overworld, `1` the End).
-    fn has(&self, world: i32) -> bool {
-        self.worlds.iter().any(|(w, _)| *w == world)
-    }
-
-    /// The layers whose conditions hold, eased over their `transition`, at the brightness of
-    /// their fade times.
-    fn draws(
-        &self,
-        world: i32,
-        conditions: &engine::Conditions,
-        sun_turns: f32,
-        seconds: f32,
-        state: &mut State,
-        out: &mut Vec<Draw>,
-    ) {
-        let conditions = &Conditions {
-            day_time: conditions.day_time,
-            weather: match conditions.weather {
-                engine::Weather::Clear => Now::Clear,
-                engine::Weather::Rain => Now::Rain,
-                engine::Weather::Thunder => Now::Thunder,
-            },
-            biome: conditions.biome,
-            y: conditions.y,
-        };
-        out.clear();
-        let mut first = 0;
-        let mut found = None;
-        for (w, layers) in &self.worlds {
-            if *w == world {
-                found = Some(layers);
-                break;
-            }
-            first += layers.len();
-        }
-        let Some(layers) = found else {
-            state.world = None;
-            return;
-        };
-        // A new world (or pack) starts each layer where its conditions put it: no fade in.
-        let snap = state.world != Some(world) || state.eased.len() != layers.len();
-        if snap {
-            state.world = Some(world);
-            state.eased.clear();
-            state.eased.resize(layers.len(), 0.0);
-        }
-        for (i, (layer, eased)) in layers.iter().zip(&mut state.eased).enumerate() {
-            let target = if layer.shows(conditions) { 1.0 } else { 0.0 };
-            let shown = if snap {
-                *eased = target;
-                target
-            } else {
-                let mut t = Transition { value: *eased };
-                *eased = t.step(target, seconds, layer.transition);
-                *eased
-            };
-            let brightness = shown * layer.brightness(conditions.day_time);
-            if brightness <= 0.0 {
-                continue;
-            }
-            let turns = layer.turns(conditions.day_time, sun_turns);
-            let rotation = if turns == 0.0 {
-                Mat4::IDENTITY
-            } else {
-                Mat4::from_axis_angle(Vec3::from_array(layer.axis), turns * std::f32::consts::TAU)
-            };
-            out.push(Draw {
-                image: (first + i) as u16,
-                blend: blend(layer.blend),
-                brightness,
-                rotation,
-            });
-        }
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::custom_sky::{Conditions, Weather};
-
-    fn pack(files: &[(&str, &str)]) -> (std::path::PathBuf, CustomSky) {
-        let root = std::env::temp_dir().join(format!(
-            "horizon-custom-sky-{}-{}",
-            std::process::id(),
-            files.len()
-        ));
-        let _ = std::fs::remove_dir_all(&root);
-        let dir = root.join("assets/minecraft/optifine/sky/world0");
-        std::fs::create_dir_all(&dir).unwrap();
-        let png = {
-            let mut bytes = Vec::new();
-            let mut encoder = png::Encoder::new(&mut bytes, 6, 4);
-            encoder.set_color(png::ColorType::Rgba);
-            encoder.set_depth(png::BitDepth::Eight);
-            let mut writer = encoder.write_header().unwrap();
-            writer
-                .write_image_data(&[255, 0, 0, 255].repeat(24))
-                .unwrap();
-            writer.finish().unwrap();
-            bytes
-        };
-        for (name, text) in files {
-            std::fs::write(dir.join(format!("{name}.properties")), text).unwrap();
-            std::fs::write(dir.join(format!("{name}.png")), &png).unwrap();
-        }
-        let sky = CustomSky::load(&root);
-        (root, sky)
-    }
-
-    fn noon(biome: &str) -> Conditions<'_> {
-        Conditions {
-            day_time: 6000,
-            weather: Weather::Clear,
-            biome,
-            y: 64,
-        }
-    }
-
-    #[test]
-    fn layers_ease_in_at_a_biome_border_but_not_on_arrival() {
-        let (root, sky) = pack(&[
-            ("sky1", "biomes=desert\ntransition=2"),
-            ("sky2", "blend=alpha\nrotate=false"),
-        ]);
-        let _ = std::fs::remove_dir_all(root);
-        assert!(sky.has(0) && !sky.has(1));
-        assert_eq!(sky.images[0].width, 6);
-        let (mut state, mut out) = (State::default(), Vec::new());
-        sky.draws(
-            0,
-            &noon("minecraft:desert"),
-            0.0,
-            0.05,
-            &mut state,
-            &mut out,
-        );
-        assert_eq!(
-            out.iter().map(|d| d.brightness).collect::<Vec<_>>(),
-            [1.0, 1.0]
-        );
-        // Out of the desert: the first layer fades over its two seconds.
-        sky.draws(0, &noon("minecraft:plains"), 0.0, 0.5, &mut state, &mut out);
-        assert_eq!(out[0].brightness, 0.75);
-        assert_eq!(out[1].blend, engine::Blend::Alpha);
-        sky.draws(0, &noon("minecraft:plains"), 0.0, 2.0, &mut state, &mut out);
-        assert_eq!(out.len(), 1, "a dark layer is not drawn");
-        assert_eq!(out[0].image, 1);
-        // Into the End, which has no layers, and back: no fade.
-        sky.draws(1, &noon("minecraft:desert"), 0.0, 0.0, &mut state, &mut out);
-        assert!(out.is_empty());
-        sky.draws(0, &noon("minecraft:desert"), 0.0, 0.0, &mut state, &mut out);
-        assert_eq!(out.len(), 2);
-    }
-
-    #[test]
-    fn a_layer_turns_west_like_the_sun() {
-        let (root, sky) = pack(&[("sky1", "")]);
-        let _ = std::fs::remove_dir_all(root);
-        let (mut state, mut out) = (State::default(), Vec::new());
-        // A quarter turn after noon (sunset): the skybox's zenith has gone down to the west.
-        let c = Conditions {
-            day_time: 12000,
-            ..noon("minecraft:plains")
-        };
-        sky.draws(0, &c, 0.25, 0.0, &mut state, &mut out);
-        let up = out[0].rotation.transform_vector3(Vec3::Y);
-        assert!((up - Vec3::NEG_X).length() < 1e-5, "{up}");
-    }
-}
@@ -1,26 +0,0 @@
-//! The resource pack formats vanilla doesn't read (OptiFine's, Polytone's) on the engine's
-//! extension points ([`crate::pack_hooks`]). This is platform code (docs/layers.md) kept in this
-//! crate until the platform's executable installs it: it uses only the crate's public API, so it
-//! moves to a platform crate unchanged, and nothing else in the crate names it.
-
-mod custom_sky;
-
-use std::path::Path;
-use std::sync::Arc;
-
-use crate::pack_hooks::PackFormats;
-
-/// OptiFine's and Polytone's formats.
-pub struct Formats;
-
-impl PackFormats for Formats {
-    fn custom_sky(&self, root: &Path) -> Option<Arc<dyn crate::custom_sky::SkyLayers>> {
-        let sky = custom_sky::CustomSky::load(root);
-        (!sky.is_empty()).then(|| Arc::new(sky) as _)
-    }
-}
-
-/// Installs these formats ([`crate::pack_hooks::install`]); the game does at startup.
-pub fn install() {
-    crate::pack_hooks::install(&Formats);
-}
@@ -1,35 +0,0 @@
-//! The engine's extension points for resource pack formats vanilla doesn't read (OptiFine's,
-//! Polytone's: platform code, docs/layers.md). The engine asks [`formats`] once per pack load and
-//! gets engine types back (tables, or an object it calls at most once a frame), never a format's
-//! own types. The platform installs its formats at startup ([`install`]); with none installed,
-//! packs load as vanilla reads them.
-
-use std::path::Path;
-use std::sync::{Arc, OnceLock};
-
-/// What the pack formats beyond vanilla's add to a pack. Each method reads one overlay of a pack
-/// (its folder at `root`); the default is "nothing in this format".
-pub trait PackFormats: Send + Sync {
-    /// The sky layers the overlay draws over the vanilla sky, if it has any.
-    fn custom_sky(&self, _root: &Path) -> Option<Arc<dyn crate::custom_sky::SkyLayers>> {
-        None
-    }
-}
-
-/// No format beyond vanilla's.
-struct Vanilla;
-
-impl PackFormats for Vanilla {}
-
-static FORMATS: OnceLock<&'static dyn PackFormats> = OnceLock::new();
-
-/// Installs the pack formats, before the first pack loads. The first call wins: later ones are
-/// ignored, so each test or probe that needs the formats may install them.
-pub fn install(formats: &'static dyn PackFormats) {
-    let _ = FORMATS.set(formats);
-}
-
-/// The installed pack formats, or vanilla's alone.
-pub fn formats() -> &'static dyn PackFormats {
-    FORMATS.get().copied().unwrap_or(&Vanilla)
-}
@@ -2,8 +2,6 @@
 //! `redstone.<power>`), for drawing only: the pack recolours collars, tropical fish, banners, wool,
 //! sign text and redstone wire and dust, while gameplay (crafting, item data, the beacon) keeps
 //! vanilla's `DyeColor`. Lock-free: the draw paths and the mesher's workers read it per face.
-use std::path::Path;
-use std::sync::RwLock;
 use std::sync::atomic::{AtomicU64, Ordering::Relaxed};

 use crate::block_entity_render::DYES;
@@ -32,96 +30,6 @@ pub fn set(colors: &PackColors) {
    }
 }

-/// An item modifier's `bar_color` of the `damage` type: a row of colours picked by the stack's
-/// damage, the first pixel undamaged, the last at full damage (measured on the real mod).
-struct DamageBar {
-    targets: horizon_polytone::Targets,
-    row: Vec<u32>,
-}
-static ITEM_BARS: RwLock<Vec<DamageBar>> = RwLock::new(Vec::new());
-
-/// Reads the packs' item modifiers' durability bar colours under a pack overlay root: an
-/// `<item>_bar.png` alone, or a json whose `bar_color` is `damage` with its `<name>_bar.png` (or
-/// `<name>.png`) beside it. Colormap ids and inline colormaps aren't read.
-pub fn set_item_bars(root: &Path) {
-    let mut bars = Vec::new();
-    for namespace in std::fs::read_dir(root.join("assets"))
-        .into_iter()
-        .flatten()
-        .flatten()
-    {
-        let base = namespace.path().join("polytone/item_modifiers");
-        let mut stack = vec![base.clone()];
-        while let Some(dir) = stack.pop() {
-            for entry in std::fs::read_dir(&dir).into_iter().flatten().flatten() {
-                let path = entry.path();
-                if path.is_dir() {
-                    stack.push(path);
-                } else if let Some(bar) = item_bar(root, &base, &path) {
-                    bars.push(bar);
-                }
-            }
-        }
-    }
-    *ITEM_BARS.write().unwrap_or_else(|e| e.into_inner()) = bars;
-}
-
-fn item_bar(root: &Path, base: &Path, path: &Path) -> Option<DamageBar> {
-    let name = path.file_name()?.to_str()?;
-    let row = |png: &Path| {
-        let (width, _, rgba) = crate::sprites::read_rgba(png).ok()?;
-        let row: Vec<u32> = rgba[..width as usize * 4]
-            .as_chunks::<4>()
-            .0
-            .iter()
-            .map(|p| u32::from(p[0]) << 16 | u32::from(p[1]) << 8 | u32::from(p[2]))
-            .collect();
-        (!row.is_empty()).then_some(row)
-    };
-    if let Some(stem) = name.strip_suffix("_bar.png") {
-        // A json of the same name owns its png.
-        if path.with_file_name(format!("{stem}.json")).exists() {
-            return None;
-        }
-        let relative = path.parent()?.strip_prefix(base).ok()?.join(stem);
-        let namespace = base.parent()?.parent()?.file_name()?.to_str()?;
-        let id = format!("{namespace}:{}", relative.to_str()?.replace('\\', "/"));
-        let targets = horizon_polytone::Targets::parse(None, Some(&id)).ok()?;
-        return Some(DamageBar {
-            targets,
-            row: row(path)?,
-        });
-    }
-    let stem = name.strip_suffix(".json")?;
-    let json: serde_json::Value = horizon_world::json_file::read(path).ok()?;
-    if json.get("bar_color")?.as_str()? != "damage" {
-        return None;
-    }
-    let png = [format!("{stem}_bar.png"), format!("{stem}.png")]
-        .into_iter()
-        .map(|png| path.with_file_name(png))
-        .find(|png| png.exists())?;
-    let relative = path.strip_prefix(root).unwrap_or(path).to_string_lossy();
-    let implicit = horizon_polytone::implicit_id(&relative, "item_modifiers");
-    let targets =
-        horizon_polytone::Targets::parse(json.get("targets"), implicit.as_deref()).ok()?;
-    Some(DamageBar {
-        targets,
-        row: row(&png)?,
-    })
-}
-
-/// A pack's durability bar colour (RGB) for an item at this damage (0 to 1).
-pub fn item_bar_color(item: &str, damage: f32) -> Option<u32> {
-    let bars = ITEM_BARS.read().unwrap_or_else(|e| e.into_inner());
-    let bar = bars
-        .iter()
-        .rev()
-        .find(|b| b.targets.matches(item, |_| false))?;
-    let last = (bar.row.len() - 1) as f32;
-    Some(bar.row[(damage.clamp(0.0, 1.0) * last).round() as usize])
-}
-
 fn read(table: &[AtomicU64; 16], i: usize) -> Option<u32> {
    let v = table[i & 15].load(Relaxed);
    (v != 0).then_some(v as u32)
@@ -188,49 +96,4 @@ mod tests {
        assert_eq!(sheep_wool(pink as u8), 0xB6687F);
        std::fs::remove_dir_all(&dir).ok();
    }
-
-    fn png_row(path: &Path, pixels: &[[u8; 3]]) {
-        std::fs::create_dir_all(path.parent().unwrap()).unwrap();
-        let file = std::fs::File::create(path).unwrap();
-        let mut encoder = png::Encoder::new(file, pixels.len() as u32, 1);
-        encoder.set_color(png::ColorType::Rgba);
-        let data: Vec<u8> = pixels
-            .iter()
-            .flat_map(|p| [p[0], p[1], p[2], 255])
-            .collect();
-        encoder
-            .write_header()
-            .unwrap()
-            .write_image_data(&data)
-            .unwrap();
-    }
-
-    #[test]
-    fn a_damage_bar_picks_its_pixel_by_the_stacks_damage() {
-        let dir = std::env::temp_dir().join(format!("pack-bars-{}", std::process::id()));
-        let modifiers = dir.join("assets/minecraft/polytone/item_modifiers");
-        let rgby = [[255, 0, 0], [0, 255, 0], [0, 0, 255], [255, 255, 0]];
-        png_row(&modifiers.join("diamond_pickaxe_bar.png"), &rgby);
-        std::fs::write(
-            modifiers.join("tools.json"),
-            r#"{"targets": ["minecraft:iron_axe"], "bar_color": "damage"}"#,
-        )
-        .unwrap();
-        png_row(&modifiers.join("tools_bar.png"), &[[1, 2, 3], [4, 5, 6]]);
-        set_item_bars(&dir);
-        // The real mod: damage 200 of 1561 shows the first pixel, 1400 the last.
-        assert_eq!(
-            item_bar_color("minecraft:diamond_pickaxe", 200.0 / 1561.0),
-            Some(0xFF0000)
-        );
-        assert_eq!(
-            item_bar_color("minecraft:diamond_pickaxe", 1400.0 / 1561.0),
-            Some(0xFFFF00)
-        );
-        assert_eq!(item_bar_color("minecraft:iron_axe", 0.9), Some(0x040506));
-        assert_eq!(item_bar_color("minecraft:diamond_shovel", 0.5), None);
-        set_item_bars(&dir.join("none"));
-        assert_eq!(item_bar_color("minecraft:diamond_pickaxe", 0.5), None);
-        std::fs::remove_dir_all(&dir).ok();
-    }
 }
@@ -31,7 +31,6 @@ mod native;
 pub mod polytone;
 mod polytone_gpu;
 mod polytone_model;
-mod spawn;
 pub use native::{ParticleController, ParticleUpdate};

 /// `ParticleOptions` with the parameters of the option classes used here.
@@ -1223,9 +1222,8 @@ pub struct ParticleLevel<'a> {
    pub collision: &'a BlockCollisionRegistry<'a>,
    /// Local player feet position and vertical velocity (`PlayerCloudParticle`).
    pub player: Option<([f64; 3], f64)>,
-    pub cached_chunk: std::cell::Cell<Option<((i32, i32), Option<&'a crate::chunk::Chunk>)>>,
 }
-impl<'a> ParticleLevel<'a> {
+impl ParticleLevel<'_> {
    fn collide(&self, bb: Aabb, d: [f64; 3]) -> [f64; 3] {
        let mut scene = SceneCollisions {
            world: self.world,
@@ -1233,6 +1231,9 @@ impl<'a> ParticleLevel<'a> {
            subject: None,
        };
        let movement = Vec3::new(d[0], d[1], d[2]);
+        // `Entity.collideBoundingBox(null, ...)`: no entity shapes, no border. Where no
+        // block of the swept box's cells can collide, it finds no shape and the
+        // movement stands, as the resolution below would return it.
        if scene.cells_without_collision(bb.expand_towards(movement)) {
            return d;
        }
@@ -1248,46 +1249,38 @@ impl<'a> ParticleLevel<'a> {
            p[2].floor() as i32,
        ]
    }
-    #[inline]
-    pub fn block(&self, x: i32, y: i32, z: i32) -> horizon_world::registry::BlockStateId {
-        let (cx, cz) = (x >> 4, z >> 4);
-        let chunk = match self.cached_chunk.get() {
-            Some(((ccx, ccz), c)) if ccx == cx && ccz == cz => c,
-            _ => {
-                let c = self.world.chunks.get(&(cx, cz)).map(|c| c.as_ref());
-                self.cached_chunk.set(Some(((cx, cz), c)));
-                c
-            }
-        };
-        chunk.map_or(self.world.air, |c| c.block(x & 15, y, z & 15))
-    }
    /// The fluid at a block and `FluidState.getHeight`.
    fn fluid(&self, b: [i32; 3]) -> (Fluid, f64) {
-        let s = self.facts.get(self.block(b[0], b[1], b[2]));
+        let s = self.facts.get(self.world.block(b[0], b[1], b[2]));
        if s.fluid == Fluid::None {
            return (Fluid::None, 0.0);
        }
-        let above = self.facts.get(self.block(b[0], b[1] + 1, b[2]));
-        let h = if above.fluid == s.fluid {
+        let above = self.facts.get(self.world.block(b[0], b[1] + 1, b[2]));
+        let height = if above.fluid == s.fluid {
            1.0
        } else {
            f64::from(s.fluid_level) / 9.0
        };
-        (s.fluid, h)
+        (s.fluid, height)
    }
    /// The fluid at a block and whether it is a source (`FluidState.isSource`).
    pub(crate) fn fluid_source(&self, b: [i32; 3]) -> (Fluid, bool) {
-        let s = self.facts.get(self.block(b[0], b[1], b[2]));
+        let s = self.facts.get(self.world.block(b[0], b[1], b[2]));
        (s.fluid, s.fluid_level == 8 && !s.fluid_falling)
    }
    /// `getCollisionShape(...).max(Y, x, z)` for cached shapes.
    fn collision_top(&self, b: [i32; 3], fx: f64, fz: f64) -> f64 {
-        let state = self.block(b[0], b[1], b[2]);
+        let state = self.world.block(b[0], b[1], b[2]);
        match self.collision.cached_shapes().cached_shape(state) {
            Ok(Some(shape)) if !shape.is_empty() => shape.max_at(Axis::Y, fx, fz),
            Ok(Some(_)) => 0.0,
-            _ if self.facts.get(state).full_collision => 1.0,
-            _ => 0.0,
+            _ => {
+                if self.facts.get(state).full_collision {
+                    1.0
+                } else {
+                    0.0
+                }
+            }
        }
    }
 }
@@ -2027,6 +2020,73 @@ impl ParticleEngine {
            (eye[0] - pos[0]).powi(2) + (eye[1] - pos[1]).powi(2) + (eye[2] - pos[2]).powi(2) <= 9.0
        })
    }
+    /// `ClientPacketListener.handleParticleEvent` for `ServerLevel.sendParticles`.
+    pub fn send_particles(
+        &mut self,
+        options: &ParticleOptions,
+        at: [f64; 3],
+        spread: [f64; 3],
+        speed: f64,
+        count: u32,
+    ) {
+        if count == 0 {
+            let v = [speed * spread[0], speed * spread[1], speed * spread[2]];
+            self.add(options, at, v);
+            return;
+        }
+        for _ in 0..count {
+            let r = &mut self.random;
+            let p = [
+                at[0] + r.next_gaussian() * spread[0],
+                at[1] + r.next_gaussian() * spread[1],
+                at[2] + r.next_gaussian() * spread[2],
+            ];
+            let v = [
+                r.next_gaussian() * speed,
+                r.next_gaussian() * speed,
+                r.next_gaussian() * speed,
+            ];
+            self.add(options, p, v);
+        }
+    }
+    /// `ParticleEngine.createParticle`: always spawned, but `ParticleEngine.add`
+    /// drops a spore blossom air particle once `ParticleLimit.SPORE_BLOSSOM` is full.
+    pub fn create(&mut self, options: &ParticleOptions, p: [f64; 3], v: [f64; 3]) {
+        if let Some(requests) = &mut self.created_requests {
+            requests.push((options.clone(), p, v));
+            return;
+        }
+        let seed = self.seeds.next_long();
+        if let Some(mut particle) = self.make(options, p, v, seed) {
+            *self.made.entry(options.ty.name()).or_default() += 1;
+            // Resource packs' Polytone particle modifiers (#11486), once as it spawns.
+            if let Some(registry) = &self.polytone
+                && registry.modifies_particles()
+            {
+                let id = match &options.mod_particle {
+                    Some(name) => name.clone(),
+                    None => format!("minecraft:{}", options.ty.name()),
+                };
+                polytone::modify(registry, &id, options.source.as_deref(), &mut particle);
+            }
+            // The provider has drawn, so rejecting here keeps vanilla's RNG order.
+            // shortcut: counts live plus queued particles by scanning instead of
+            // vanilla's counted map; use a counter if spore spawning shows in profiles.
+            if particle.ty == ParticleType::SporeBlossomAir
+                && self.particles.len() + self.pending.len() >= SPORE_BLOSSOM_LIMIT
+                && self
+                    .particles
+                    .iter()
+                    .chain(self.pending.iter())
+                    .filter(|q| q.ty == ParticleType::SporeBlossomAir)
+                    .count()
+                    >= SPORE_BLOSSOM_LIMIT
+            {
+                return;
+            }
+            self.pending.push(particle);
+        }
+    }
    /// How many particles of each type were made so far.
    pub fn made(&self) -> &std::collections::BTreeMap<&'static str, u64> {
        &self.made
@@ -3992,12 +4052,15 @@ impl ParticleEngine {
            }
            Behaviour::Lava => {
                p.base_tick(level);
-                if !p.removed && p.random.next_float() > p.age as f32 / p.lifetime as f32 {
-                    self.add(
-                        &ParticleOptions::simple(ParticleType::Smoke),
-                        p.position,
-                        p.velocity,
-                    );
+                if !p.removed {
+                    let odds = p.age as f32 / p.lifetime as f32;
+                    if p.random.next_float() > odds {
+                        self.add(
+                            &ParticleOptions::simple(ParticleType::Smoke),
+                            p.position,
+                            p.velocity,
+                        );
+                    }
                }
            }
            Behaviour::Crit => {
@@ -4081,7 +4144,9 @@ impl ParticleEngine {
                    *c *= f64::from(0.98f32);
                }
                if p.on_ground {
-                    p.removed |= p.random.next_float() < 0.5;
+                    if p.random.next_float() < 0.5 {
+                        p.removed = true;
+                    }
                    p.velocity[0] *= f64::from(0.7f32);
                    p.velocity[2] *= f64::from(0.7f32);
                }
@@ -4121,10 +4186,13 @@ impl ParticleEngine {
            } => {
                p.base_tick(level);
                let (fluid, source) = level.fluid_source(ParticleLevel::block_at(p.position));
-                if !(fluid == Fluid::Water && source)
-                    || p.position[1] >= y_end
-                    || p.position[1] <= y_prev
-                {
+                if !(p.removed || (fluid == Fluid::Water && source)) {
+                    p.removed = true;
+                }
+                if !p.removed && p.position[1] >= y_end {
+                    p.removed = true;
+                }
+                if !p.removed && p.position[1] <= y_prev {
                    p.removed = true;
                }
                // randomHorizontalWiggling, then a second, horizontal move.
@@ -4148,8 +4216,9 @@ impl ParticleEngine {
                p.base_tick(level);
                self.sprite_from_age(p);
                if p.age as f32 > fade_start {
+                    let frames_since_fade_out_start = p.age as f32 - fade_start;
                    p.rgba[3] =
-                        (p.lifetime as f32 - (p.age as f32 - fade_start)) / p.lifetime as f32;
+                        (p.lifetime as f32 - frames_since_fade_out_start) / p.lifetime as f32;
                }
            }
            Behaviour::NoxiousGasCloud => {
@@ -4613,7 +4682,7 @@ impl ParticleEngine {
                    self.sprite_from_age(p);
                    half(p);
                    let b = ParticleLevel::block_at(p.position);
-                    if level.facts.is_air(level.block(b[0], b[1], b[2])) {
+                    if level.facts.is_air(level.world.block(b[0], b[1], b[2])) {
                        p.velocity[1] -= f64::from(0.0074f32);
                    }
                }
@@ -4621,7 +4690,7 @@ impl ParticleEngine {
            Behaviour::Firefly => {
                p.base_tick(level);
                let b = ParticleLevel::block_at(p.position);
-                if !level.facts.is_air(level.block(b[0], b[1], b[2])) {
+                if !level.facts.is_air(level.world.block(b[0], b[1], b[2])) {
                    p.removed = true;
                } else {
                    p.rgba[3] = fade_amount(p.lifetime_progress(p.age as f32), 0.3, 0.5);
@@ -5085,12 +5154,11 @@ fn hdr_tier(ty: ParticleType) -> u8 {
 }
 /// `Particle.LifetimeAlpha.currentAlphaForAge`.
 fn lifetime_alpha(a: [f32; 4], age: i32, lifetime: i32, partial: f32) -> f32 {
-    let t = ((age as f32 + partial) / lifetime as f32 - a[2]) / (a[3] - a[2]);
    if (a[0] - a[1]).abs() < 1.0e-5 {
-        a[0]
-    } else {
-        a[0] + (a[1] - a[0]) * t.clamp(0.0, 1.0)
+        return a[0];
    }
+    let t = ((age as f32 + partial) / lifetime as f32 - a[2]) / (a[3] - a[2]);
+    a[0] + (a[1] - a[0]) * t.clamp(0.0, 1.0)
 }

 struct Starter {
@@ -5521,7 +5589,6 @@ mod tests {
            facts: &facts,
            collision: &collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = ParticleEngine::new(Path::new(""), &HashMap::new(), &HashSet::new());
        engine.set_sprites.push(vec![10, 11, 12]);
@@ -5613,7 +5680,6 @@ mod tests {
            facts: &facts,
            collision: &collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = ParticleEngine::new(Path::new(""), &HashMap::new(), &HashSet::new());
        let mut particle = Particle::blank(ParticleType::Smoke, [0.0; 3]);
@@ -124,7 +124,6 @@ mod tests {
            facts: &facts,
            collision: &collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut e = engine();
        let mut p = e
@@ -490,14 +490,14 @@ enum Subject<'a> {
 }

 /// What one expression runs against: its subject, the frame and the level.
-struct Ctx<'a, 'l> {
+struct Ctx<'a> {
    subject: Subject<'a>,
    random: &'a mut LegacyRandom,
    custom: &'a mut f64,
    customs: &'a mut BTreeMap<String, f64>,
    frame: &'a Frame,
    registry: &'a Registry,
-    level: Option<&'a ParticleLevel<'l>>,
+    level: Option<&'a ParticleLevel<'a>>,
    blocks: Vec<[i32; 3]>,
 }

@@ -515,7 +515,7 @@ fn axis(name: &str) -> usize {
    usize::from(name.as_bytes()[0] - b'x')
 }

-impl Ctx<'_, '_> {
+impl Ctx<'_> {
    fn position(&self) -> [f64; 3] {
        match &self.subject {
            Subject::Particle(p) => p.position,
@@ -683,7 +683,7 @@ impl Ctx<'_, '_> {
    }
 }

-impl Host for Ctx<'_, '_> {
+impl Host for Ctx<'_> {
    fn root(&mut self, root: Root) -> V {
        match root {
            Root::Object => V::Object(SELF),
@@ -1662,7 +1662,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        // Air has no emitters; the torch fires its first emitter only.
@@ -1702,7 +1701,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        engine.polytone_animate(&level, [1, 64, 1]);
@@ -1724,7 +1722,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        engine.polytone_animate(&level, [1, 64, 1]);
@@ -1770,7 +1767,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let registry = Registry::read(&root, Default::default(), blocks);
        let frame = registry.frame.clone();
@@ -1824,7 +1820,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let registry = Registry::read(&root, Default::default(), blocks);
        let mut engine = engine(registry);
@@ -1858,7 +1853,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        let rect = crate::hud::Rect {
@@ -1911,7 +1905,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        let rect = crate::hud::Rect {
@@ -1973,7 +1966,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        engine.polytone_entity(&level, "minecraft:player", [1.0, 70.0, 1.0]);
@@ -2022,7 +2014,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        let rect = crate::hud::Rect {
@@ -2089,7 +2080,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let registry = Arc::new(Registry::read(&root, Default::default(), blocks));
        // The chunk's biome is id 0: plains, whose foliage is #336699.
@@ -2208,7 +2198,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        engine.polytone_entity(&level, "minecraft:player", [1.5, 70.0, 1.5]);
@@ -2287,7 +2276,6 @@ mod tests {
            facts: &scene.facts,
            collision: &scene.collision,
            player: None,
-            cached_chunk: std::cell::Cell::new(None),
        };
        let mut engine = engine(Registry::read(&root, Default::default(), blocks));
        // The test chunk's biome is the table's first: a cold one first, then a warm one.
@@ -1,73 +0,0 @@
-//! Where particles come into the engine: a server's particle packet and a single particle made
-//! where the game asks for one.
-use super::*;
-
-impl ParticleEngine {
-    /// `ClientPacketListener.handleParticleEvent` for `ServerLevel.sendParticles`.
-    pub fn send_particles(
-        &mut self,
-        options: &ParticleOptions,
-        at: [f64; 3],
-        spread: [f64; 3],
-        speed: f64,
-        count: u32,
-    ) {
-        if count == 0 {
-            let v = [speed * spread[0], speed * spread[1], speed * spread[2]];
-            self.add(options, at, v);
-            return;
-        }
-        for _ in 0..count {
-            let r = &mut self.random;
-            let p = [
-                at[0] + r.next_gaussian() * spread[0],
-                at[1] + r.next_gaussian() * spread[1],
-                at[2] + r.next_gaussian() * spread[2],
-            ];
-            let v = [
-                r.next_gaussian() * speed,
-                r.next_gaussian() * speed,
-                r.next_gaussian() * speed,
-            ];
-            self.add(options, p, v);
-        }
-    }
-    /// `ParticleEngine.createParticle`: always spawned, but `ParticleEngine.add`
-    /// drops a spore blossom air particle once `ParticleLimit.SPORE_BLOSSOM` is full.
-    pub fn create(&mut self, options: &ParticleOptions, p: [f64; 3], v: [f64; 3]) {
-        if let Some(requests) = &mut self.created_requests {
-            requests.push((options.clone(), p, v));
-            return;
-        }
-        let seed = self.seeds.next_long();
-        if let Some(mut particle) = self.make(options, p, v, seed) {
-            *self.made.entry(options.ty.name()).or_default() += 1;
-            // Resource packs' Polytone particle modifiers (#11486), once as it spawns.
-            if let Some(registry) = &self.polytone
-                && registry.modifies_particles()
-            {
-                let id = match &options.mod_particle {
-                    Some(name) => name.clone(),
-                    None => format!("minecraft:{}", options.ty.name()),
-                };
-                polytone::modify(registry, &id, options.source.as_deref(), &mut particle);
-            }
-            // The provider has drawn, so rejecting here keeps vanilla's RNG order.
-            // shortcut: counts live plus queued particles by scanning instead of
-            // vanilla's counted map; use a counter if spore spawning shows in profiles.
-            if particle.ty == ParticleType::SporeBlossomAir
-                && self.particles.len() + self.pending.len() >= SPORE_BLOSSOM_LIMIT
-                && self
-                    .particles
-                    .iter()
-                    .chain(self.pending.iter())
-                    .filter(|q| q.ty == ParticleType::SporeBlossomAir)
-                    .count()
-                    >= SPORE_BLOSSOM_LIMIT
-            {
-                return;
-            }
-            self.pending.push(particle);
-        }
-    }
-}
@@ -93,7 +93,6 @@ fn particle_tick_cost() {
        facts: &facts,
        collision: &collision,
        player: None,
-        cached_chunk: std::cell::Cell::new(None),
    };
    let ty = |name: &str| ParticleType::from_name(name).unwrap();
    let (fx, fy, fz) = (0.5, f64::from(FLOOR_Y + 5), 20.5);
@@ -337,13 +337,6 @@ impl Settings {
            .and_then(|mode| self.video_modes.iter().position(|m| *m == mode))
            .map_or(-1, |i| i as i32)
    }
-    /// Loads only the crates' settings stores (`horizon_hooks::settings`) from the files next to
-    /// `path`, into the seat whose turn it is (`horizon_hooks::seat`): a splitscreen player whose
-    /// settings were made from P1's rather than loaded.
-    pub fn load_stores(path: &Path) {
-        let dir = path.parent();
-        horizon_hooks::settings::engine::load(&mut |file| fs::read_to_string(dir?.join(file)).ok());
-    }
    pub fn load(path: &Path) -> Self {
        let mut horizon = path
            .parent()
@@ -369,13 +362,6 @@ impl Settings {
            .and_then(|dir| fs::read_to_string(dir.join(crate::extras::FILE)).ok())
            .unwrap_or_default();
        let mut extras = crate::extras::Extras::parse(&extras_text);
-        // The settings stores of the crates above the engine: their lines of this file, or of
-        // their own (docs/layers.md, "Platform registries").
-        horizon_hooks::settings::engine::load(&mut |file| match path.parent() {
-            _ if file == crate::extras::FILE => Some(extras_text.clone()),
-            Some(dir) => fs::read_to_string(dir.join(file)).ok(),
-            None => None,
-        });
        // The enabled mods are the game folder's, shared by its players (`--player-dir`).
        let mods = path
            .parent()
@@ -704,7 +690,6 @@ impl Settings {
            let mut extras = self.extras.clone();
            extras.emote_key = self.keys.get("key.emote").to_owned();
            extras.save(dir);
-            horizon_hooks::settings::engine::save_own(dir, &[crate::extras::FILE]);
            self.mods.save(&crate::logging::shared_dir(dir));
        }
    }
@@ -871,8 +856,6 @@ pub enum Opt {
    PadGameplayGuide,
    /// `options.modelPart.*`: one skin layer (index into `options_file::MODEL_PARTS`).
    ModelPart(usize),
-    /// A slider of a page a crate registered (`horizon_hooks::pages`): (page, row).
-    Page(usize, usize),
    /// 3D skin layers: the player's outer layer as extruded slabs.
    SkinLayers3d,
    MainHand,
@@ -192,12 +192,7 @@ impl SignData {
        let side = |t: Option<&Tag>| -> SignText {
            let mut out = SignText::default();
            let Some(t) = t else { return out };
-            if let Some(messages) = t.get("messages") {
-                // `SignText.CODEC` reads a side all or nothing: a messages
-                // field that is not a list leaves the side empty.
-                let Tag::List(messages) = messages else {
-                    return SignText::default();
-                };
+            if let Some(Tag::List(messages)) = t.get("messages") {
                for (i, m) in messages.iter().take(4).enumerate() {
                    out.lines[i] = component_text(m);
                    out.click[i] = click_event(m);
@@ -312,27 +307,6 @@ pub fn editor_sprite(folder: &str, wood: &str) -> String {
 #[cfg(test)]
 mod tests {
    use super::*;
-    /// `SignText.CODEC` reads messages as a list: a string field fails the
-    /// whole side, taking its colour and glow with it.
-    #[test]
-    fn messages_that_are_not_a_list_load_an_empty_side() {
-        let tag = Tag::compound([(
-            "front_text",
-            Tag::compound([
-                ("messages", Tag::String("not a list".into())),
-                ("color", Tag::String("red".into())),
-                ("has_glowing_text", Tag::Byte(1)),
-            ]),
-        )]);
-        let mut decoded = SignData::default();
-        decoded.decode(&tag);
-        assert_eq!(
-            decoded.front,
-            SignText::default(),
-            "a failed message list takes the side's colour and glow with it"
-        );
-    }
-
    #[test]
    fn waxed_and_glowing_text_take_any_number() {
        let tag = Tag::compound([
@@ -549,9 +549,6 @@ pub struct Streaming {
    pub mod_forced: HashSet<(i32, i32)>,
    /// No work is scheduled while paused (title screen).
    pub paused: bool,
-    /// Finished meshes the renderer has not taken yet (the game's pending
-    /// uploads): they count against the meshing room as the jobs do.
-    pub upload_backlog: usize,
    /// Dimension flags: sky light, Nether face shading.
    pub sky_light: bool,
    pub nether_shading: bool,
@@ -1065,9 +1062,7 @@ pub struct WorkerContext {
    pub biomes: Arc<crate::biome::Biomes>,
    pub light: Arc<LightTables>,
 }
-mod bounded;
 mod relight_now;
-use bounded::nearest_first;
 impl Streaming {
    pub fn new<G: ChunkGenerator>(
        generator: Arc<G>,
@@ -1152,7 +1147,6 @@ impl Streaming {
            forced: HashSet::new(),
            mod_forced: HashSet::new(),
            paused: false,
-            upload_backlog: 0,
            sky_light: true,
            nether_shading: false,
            shader_pack_lighting: false,
@@ -2089,10 +2083,7 @@ impl Streaming {
        // jobs went stale long before a worker reached them (#3629). What
        // stays dirty is asked for again, from the current centre, as
        // capacity frees; `requeue` then has a small queue to keep close.
-        // Meshes waiting for upload count too: when uploads fall behind (a
-        // low frame rate at a wide distance), meshing on held gigabytes of
-        // them until the system swapped.
-        let room = (self.workers * 32).saturating_sub(self.meshing.len() + self.upload_backlog);
+        let room = (self.workers * 32).saturating_sub(self.meshing.len());
        nearest_first(&mut candidates, room);
        for (_, x, z, sections) in candidates.drain(..) {
            let Some(region) = Self::region(world, x, z) else {
@@ -3030,6 +3021,19 @@ fn light_region_ready(
    }
    true
 }
+/// The nearest `room` of the `candidates`, ordered: the light and mesh
+/// stages submit bounded work, chosen from everything that is ready each
+/// `update`, so what runs is always the nearest of what is left — chosen
+/// again, from the current centre, as capacity frees, the way vanilla's
+/// chunk task queues follow the current ticket levels. The selection is
+/// O(n); the sort orders only what is submitted.
+fn nearest_first<T: Ord>(candidates: &mut Vec<T>, room: usize) {
+    if candidates.len() > room {
+        candidates.select_nth_unstable(room);
+        candidates.truncate(room);
+    }
+    candidates.sort_unstable();
+}
 /// What `keep_unchanged_sections` found changed.
 #[derive(Debug, Default, PartialEq)]
 struct Resent {
@@ -3582,6 +3586,37 @@ mod tests {
        assert_eq!(pops(queue), [None]);
    }

+    /// The light and mesh stages submit bounded work, the nearest first:
+    /// what exceeds the room stays dirty, to be chosen again — from the
+    /// current centre — as capacity frees. Submitted whole, the queue once
+    /// held every ready column's jobs and grew with the render distance
+    /// (#3629); ties break by position, so the choice is deterministic.
+    #[test]
+    fn bounded_submission_takes_the_nearest_first() {
+        let candidates: Vec<(i64, i32, i32, u32)> = (0..40i32)
+            .map(|i| {
+                let (x, z) = (i / 8 - 2, i % 8 - 3);
+                (
+                    i64::from((x - 3).pow(2) + (z - 2).pow(2)),
+                    x,
+                    z,
+                    1 << (i % 24),
+                )
+            })
+            .collect();
+        let mut expected = candidates.clone();
+        expected.sort_unstable();
+        let mut none = candidates.clone();
+        nearest_first(&mut none, 0);
+        assert!(none.is_empty());
+        let mut nearest = candidates;
+        nearest_first(&mut nearest, 5);
+        assert_eq!(nearest, expected[..5]);
+        let mut past = expected.clone();
+        nearest_first(&mut past, expected.len() + 10);
+        assert_eq!(past, expected);
+    }
+
    /// What the scheduler counts as ready to light: every neighbour a
    /// finished column, or a decorated proto chunk past the area — the
    /// walk `light_region` makes without its snapshot.
@@ -1,52 +0,0 @@
-//! Bounded submission: the light and mesh stages hand the workers only the
-//! nearest of what is ready.
-
-/// The nearest `room` of the `candidates`, ordered: the light and mesh
-/// stages submit bounded work, chosen from everything that is ready each
-/// `update`, so what runs is always the nearest of what is left — chosen
-/// again, from the current centre, as capacity frees, the way vanilla's
-/// chunk task queues follow the current ticket levels. The selection is
-/// O(n); the sort orders only what is submitted.
-pub(super) fn nearest_first<T: Ord>(candidates: &mut Vec<T>, room: usize) {
-    if candidates.len() > room {
-        candidates.select_nth_unstable(room);
-        candidates.truncate(room);
-    }
-    candidates.sort_unstable();
-}
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    /// The light and mesh stages submit bounded work, the nearest first:
-    /// what exceeds the room stays dirty, to be chosen again — from the
-    /// current centre — as capacity frees. Submitted whole, the queue once
-    /// held every ready column's jobs and grew with the render distance
-    /// (#3629); ties break by position, so the choice is deterministic.
-    #[test]
-    fn bounded_submission_takes_the_nearest_first() {
-        let candidates: Vec<(i64, i32, i32, u32)> = (0..40i32)
-            .map(|i| {
-                let (x, z) = (i / 8 - 2, i % 8 - 3);
-                (
-                    i64::from((x - 3).pow(2) + (z - 2).pow(2)),
-                    x,
-                    z,
-                    1 << (i % 24),
-                )
-            })
-            .collect();
-        let mut expected = candidates.clone();
-        expected.sort_unstable();
-        let mut none = candidates.clone();
-        nearest_first(&mut none, 0);
-        assert!(none.is_empty());
-        let mut nearest = candidates;
-        nearest_first(&mut nearest, 5);
-        assert_eq!(nearest, expected[..5]);
-        let mut past = expected.clone();
-        nearest_first(&mut past, expected.len() + 10);
-        assert_eq!(past, expected);
-    }
-}
Author	SHA1	Message	Date
Horizon agentandClaude Opus 5.5	27740e2e8f	geometry.rs: GbuffersInputs only in its tests; lockfiles: the pipeline crate takes naga Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 16:46:06 +01:00
Horizon agentandClaude Opus 5.5	a7d211a1fc	Translated programs' types move to horizon-render-pipeline A translated program as the renderer builds pipelines from it (Program, ComputeProgram, Interface, Uniform, Sampler, Image, Target, Error, DRAW_UNIFORMS) and the vertex inputs the renderer offers it (GbuffersInputs, GeometryInputs, AlphaTest, WATER_MASK, WATER_PATCHES) move unchanged from horizon-shaders' translator, which re-exports them. The renderer's library code takes them from the engine crate. Layer plan M6. Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 16:42:43 +01:00
Ludovic Marie	7ae28b9d3e	Merge branch 'split/render-pipeline-stages' into split/render-pipeline-textures	2026-11-09 16:35:58 +01:00
Ludovic Marie	0b7d3f8105	Merge branch 'split/render-pipeline-config' into split/render-pipeline-stages	2026-11-09 16:35:02 +01:00
Horizon agentandClaude Opus 5.5	950c368a3c	Custom textures and render stages move to horizon-render-pipeline The textures a pipeline's programs read (CustomTexture, Texture, Texels, TextureSource, Dim, EVERY_STAGE) and the render stages they are told they draw in (RENDER_STAGES, render_stage) move unchanged from horizon-shaders, which still reads them from a pack and re-exports them. The renderer takes them from the engine crate. Layer plan M6. Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 16:24:07 +01:00
Horizon agentandClaude Opus 5.5	a6093def90	launcher and registry lockfiles: horizon-shader-api depends on horizon-render-pipeline Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 16:21:43 +01:00
Horizon agentandClaude Opus 5.5	80aa1a5b06	Cargo.lock: horizon-shader-api takes bytemuck through the pipeline crate Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 16:20:23 +01:00
Ludovic Marie	8da02c530e	Merge branch 'split/render-pipeline-config' into split/render-pipeline-stages	2026-11-09 16:20:23 +01:00
Horizon agentandClaude Opus 5.5	a23f327048	WGSL stage interface moves to horizon-render-pipeline The stages Horizon's own packs fill, their preludes, bindings and entry points (stages.rs), the frame uniform the renderer uploads (inputs.rs) and the API lines (Api) are the renderer's interface, so they move unchanged into the engine's pipeline crate. horizon-shader-api keeps reading, composing and checking packs against them and re-exports them under the same paths (launcher and registry unchanged). The renderer takes them from the engine crate. Layer plan M6. Co-Authored-By: Claude Opus 5.5 <[email protected]>	2026-11-09 15:58:12 +01:00