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29f65b8e6f
把 M61 的「OKLCh 近似 CAM16 + gamut 硬裁」换成官方的 HCT 算法，与 material-color-utilities（Apache-2.0）逐角色对上：baseline 49 角色 × light/dark、8 个种子 × 12 个强调族角色 × 2 模式，**实测每通道误差 0** （判据写入测试：≤1）。 实现（逐函数对照官方 Java 重写为 Rust，f64 内部精度）： - color/cam16.rs + viewing_conditions.rs：CAM16 色相/彩度（D65、200 lux、 背景 L* 50），默认观察条件的中间量与 Java 实测逐位对齐 - color/hct_solver.rs + critical_planes.rs：官方 gamut 映射（Newton 迭代 + 色调平面上的色相二分，255 项关键平面表原样搬运），只压彩度不硬裁 - color/hct.rs：HCT 坐标（hue/chroma/tone），公开给工具与测试 - color/space.rs：官方 ColorUtils 的 sRGB↔线性↔XYZ↔L* 换算（矩阵、阈值、 取整口径一致） - color/palettes.rs：Tonal Spot 官方彩度常数 36/16/24/6/8，error 25°/84 - color/scheme.rs：tone 表换 ColorSpec2021（on-*container 10→30、 background 99/10→98/6） 两个旧缺陷关门： - primary-container 与 secondary-container 不再撞色（彩度 36 vs 16， tone 90 装得下，无需「共享基准压彩度」补丁）；reference_chroma / tone_scaled 随之删除 - 强调色色相不再被 gamut 硬裁（只压彩度，实测偏移 <1°） 对齐证据：tests/official_baseline.rs（98 项 + 12 个 HCT 探针）、 tests/official_accent.rs（192 项）。期望值是把官方 Java 实现本机编译运行 的输出抄本，并用 Flutter 的 ColorScheme.fromSeed 用例交叉验证 （#00FF00 → #406836、#000000 → #8C4A60、#FFFFFF → #006874 一致）。 诚实口径：只做 Tonal Spot 变体 + contrastLevel 0；对比度三档、其他变体、 壁纸多色取色、非默认观察条件都在模块文档的 gap 表里登记。 注：token_pins 的 tone 值变化来自官方算法（ColorSpec2021），不是为过测试而改。 NOTICE 增「Google Material Color Utilities」归属（Apache-2.0 要求， 含逐文件映射与对齐方法）。
198 lines
8.3 KiB
Rust
198 lines
8.3 KiB
Rust
//! 与官方 `material-color-utilities` 的**逐角色对齐**（baseline 方案）。
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//!
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//! 期望值不是「我们觉得对的颜色」，而是把官方 Java 实现（Apache-2.0）编译跑出来的结果：
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//! `new SchemeTonalSpot(Hct.fromInt(0xFF6750A4), isDark, 0.0, SpecVersion.SPEC_2021, Platform.PHONE)`
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//! 配上 `ColorSpec2021` 的 49 个动态色。跑法见 `NOTICE` 的归属声明——期望值表就是那份输出的
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//! 抄本（`seed,flavor,role,hex`）。
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//!
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//! 判据是**每通道误差 ≤1**：8 bit 量化本身就有半格误差，再加上 Java `double` 与 Rust `f64`
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//! 的末位差异，1 是「同一个算法」的合理上限；2 以上就是实现真的不一样了。
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use unlucky_design::color::{Color, Hct, Role, Scheme, SchemeFlavor, BASELINE_SEED};
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/// 每通道允许的最大误差。
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const CHANNEL_TOLERANCE: i16 = 1;
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/// 官方 baseline 输出（seed `#6750A4`，Tonal Spot，ColorSpec2021，contrastLevel 0）。
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const BASELINE: [(Role, &str, &str); 49] = [
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(Role::Primary, "#65558F", "#CFBDFE"),
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(Role::OnPrimary, "#FFFFFF", "#36275D"),
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(Role::PrimaryContainer, "#E9DDFF", "#4D3D75"),
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(Role::OnPrimaryContainer, "#4D3D75", "#E9DDFF"),
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(Role::Secondary, "#625B71", "#CBC2DB"),
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(Role::OnSecondary, "#FFFFFF", "#332D41"),
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(Role::SecondaryContainer, "#E8DEF8", "#4A4458"),
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(Role::OnSecondaryContainer, "#4A4458", "#E8DEF8"),
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(Role::Tertiary, "#7E5260", "#EFB8C8"),
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(Role::OnTertiary, "#FFFFFF", "#4A2532"),
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(Role::TertiaryContainer, "#FFD9E3", "#633B48"),
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(Role::OnTertiaryContainer, "#633B48", "#FFD9E3"),
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(Role::Error, "#BA1A1A", "#FFB4AB"),
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(Role::OnError, "#FFFFFF", "#690005"),
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(Role::ErrorContainer, "#FFDAD6", "#93000A"),
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(Role::OnErrorContainer, "#93000A", "#FFDAD6"),
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(Role::Surface, "#FDF7FF", "#141218"),
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(Role::OnSurface, "#1D1B20", "#E6E0E9"),
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(Role::SurfaceVariant, "#E7E0EB", "#49454E"),
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(Role::OnSurfaceVariant, "#49454E", "#CAC4CF"),
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(Role::Background, "#FDF7FF", "#141218"),
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(Role::OnBackground, "#1D1B20", "#E6E0E9"),
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(Role::SurfaceDim, "#DED8E0", "#141218"),
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(Role::SurfaceBright, "#FDF7FF", "#3B383E"),
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(Role::SurfaceContainerLowest, "#FFFFFF", "#0F0D13"),
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(Role::SurfaceContainerLow, "#F8F2FA", "#1D1B20"),
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(Role::SurfaceContainer, "#F2ECF4", "#211F24"),
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(Role::SurfaceContainerHigh, "#ECE6EE", "#2B292F"),
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(Role::SurfaceContainerHighest, "#E6E0E9", "#36343A"),
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(Role::Outline, "#7A757F", "#948F99"),
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(Role::OutlineVariant, "#CAC4CF", "#49454E"),
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(Role::InverseSurface, "#322F35", "#E6E0E9"),
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(Role::InverseOnSurface, "#F5EFF7", "#322F35"),
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(Role::InversePrimary, "#CFBDFE", "#65558F"),
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(Role::Shadow, "#000000", "#000000"),
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(Role::Scrim, "#000000", "#000000"),
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(Role::SurfaceTint, "#65558F", "#CFBDFE"),
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(Role::PrimaryFixed, "#E9DDFF", "#E9DDFF"),
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(Role::PrimaryFixedDim, "#CFBDFE", "#CFBDFE"),
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(Role::OnPrimaryFixed, "#201047", "#201047"),
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(Role::OnPrimaryFixedVariant, "#4D3D75", "#4D3D75"),
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(Role::SecondaryFixed, "#E8DEF8", "#E8DEF8"),
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(Role::SecondaryFixedDim, "#CBC2DB", "#CBC2DB"),
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(Role::OnSecondaryFixed, "#1E192B", "#1E192B"),
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(Role::OnSecondaryFixedVariant, "#4A4458", "#4A4458"),
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(Role::TertiaryFixed, "#FFD9E3", "#FFD9E3"),
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(Role::TertiaryFixedDim, "#EFB8C8", "#EFB8C8"),
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(Role::OnTertiaryFixed, "#31101D", "#31101D"),
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(Role::OnTertiaryFixedVariant, "#633B48", "#633B48"),
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];
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/// 官方 `Hct.from(hue, chroma, tone)` 的色值（求解器与 gamut 映射的直接证据）。
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const HCT_PROBES: [(f64, f64, f64, &str); 12] = [
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(95.0, 36.0, 40.0, "#705D0D"),
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(95.0, 36.0, 90.0, "#FCE186"),
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(95.0, 16.0, 90.0, "#F0E2BB"),
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(96.0, 24.0, 80.0, "#D7C68D"),
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(25.0, 84.0, 40.0, "#BA1A1A"),
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(0.0, 0.0, 50.0, "#777777"),
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(200.0, 120.0, 70.0, "#00BEC3"),
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(30.0, 0.5, 98.0, "#FDF8F7"),
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(270.0, 200.0, 10.0, "#001847"),
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(120.0, 60.0, 99.0, "#FCFFDD"),
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(60.0, 6.0, 6.0, "#19120C"),
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(95.0, 36.0, 30.0, "#554500"),
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];
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/// 三通道里最大的绝对误差。
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fn worst_channel(got: Color, want: Color) -> i16 {
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let pairs = [(got.r, want.r), (got.g, want.g), (got.b, want.b)];
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pairs
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.iter()
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.map(|(a, b)| (i16::from(*a) - i16::from(*b)).abs())
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.max()
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.unwrap_or(0)
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}
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#[test]
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fn baseline_matches_official_on_all_forty_nine_roles() {
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let light = Scheme::baseline(SchemeFlavor::Light);
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let dark = Scheme::baseline(SchemeFlavor::Dark);
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let mut worst = 0;
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let mut off_by_one = 0;
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let mut failures = Vec::new();
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for (role, want_light, want_dark) in BASELINE {
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for (flavor, scheme, want_hex) in [
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(SchemeFlavor::Light, light, want_light),
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(SchemeFlavor::Dark, dark, want_dark),
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] {
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let got = scheme.get(role);
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let want = Color::from_hex(want_hex).expect("官方 hex 必须合法");
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let delta = worst_channel(got, want);
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worst = worst.max(delta);
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if delta > 0 {
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off_by_one += 1;
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}
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if delta > CHANNEL_TOLERANCE {
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failures.push(format!(
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"{}/{} 是 {}，官方 {want_hex}（差 {delta}）",
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flavor.name(),
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role.name(),
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got.to_hex()
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));
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}
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}
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}
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assert!(
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failures.is_empty(),
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"{} 个角色与官方不一致（容差 {CHANNEL_TOLERANCE}）：\n{}",
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failures.len(),
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failures.join("\n")
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);
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// 把误差统计打出来（`cargo test -- --nocapture` 可见），报告里要引用。
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println!("baseline 对齐：98 项，最大通道误差 {worst}，非零误差 {off_by_one} 项");
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}
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#[test]
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fn hct_solver_matches_official_color_spec_2021() {
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for (hue, chroma, tone, want_hex) in HCT_PROBES {
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let got = Hct::from_components(hue, chroma, tone).to_color();
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let want = Color::from_hex(want_hex).expect("官方 hex 必须合法");
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assert!(
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worst_channel(got, want) <= CHANNEL_TOLERANCE,
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"HCT({hue}, {chroma}, {tone}) 是 {}，官方 {want_hex}",
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got.to_hex()
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);
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}
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}
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#[test]
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fn baseline_primary_is_not_the_seed_and_that_is_official() {
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// 常见误解：baseline() 的 primary 应该等于种子 #6750A4。官方不是——Tonal Spot 变体把
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// primary 的彩度固定成 36，而 #6750A4 的 HCT 彩度是 47.86，所以 primary 被收到 #65558F。
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// 这也是 Flutter `ColorScheme.fromSeed(0xFF6750A4)` 的 primary 值。
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let seed = Hct::from_color(BASELINE_SEED);
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assert!(
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(seed.chroma - 47.856_526).abs() < 1.0e-4,
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"种子彩度 {}",
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seed.chroma
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);
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let primary = Scheme::baseline(SchemeFlavor::Light).get(Role::Primary);
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assert_eq!(primary.to_hex(), "#65558F");
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assert_ne!(primary, BASELINE_SEED);
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}
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#[test]
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fn baseline_tone_axis_is_still_exact_lstar() {
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// gamut 映射只动彩度，不动 tone：每个角色的实测 L* 与它声明的 tone 相差 ≤1。
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for flavor in [SchemeFlavor::Light, SchemeFlavor::Dark] {
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let scheme = Scheme::baseline(flavor);
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for (role, color) in scheme.iter() {
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let tone = Scheme::tone_of(role, flavor);
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let got = f64::from(color.lstar());
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assert!(
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(got - tone).abs() <= 1.0,
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"{}/{} 的 tone 声明 {tone}、实测 {got}",
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flavor.name(),
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role.name()
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);
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}
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}
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}
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#[test]
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fn same_family_containers_are_separated_by_hct_chroma() {
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// 旧缺陷①：light 下 primary-container 与 secondary-container 撞色。
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// 现在两者彩度不同（36 vs 16），在 tone 90 上都不会被色域裁到同一个上限。
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let light = Scheme::baseline(SchemeFlavor::Light);
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let primary = light.get(Role::PrimaryContainer);
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let secondary = light.get(Role::SecondaryContainer);
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assert_ne!(primary, secondary);
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let c_primary = Hct::from_color(primary).chroma;
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let c_secondary = Hct::from_color(secondary).chroma;
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assert!(
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c_secondary < c_primary,
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"secondary-container 彩度 {c_secondary} 应低于 primary-container {c_primary}"
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);
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// 深层原因：tone 90 上彩度 36 装得下，所以容器色是「真的有彩度的浅紫」而不是被裁到灰。
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assert!(c_primary > 12.0, "primary-container 彩度只剩 {c_primary}");
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}
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