RFC Phase 4: derive a whole-system color scheme from ONE brand seed at runtime.
Packages the demo-only builder into a first-class, tested API.
- build-scheme.ts (pure): buildScheme(seed, opts) composes the uix.color engine
(deriveScheme -> generateScale -> APCA on-solid -> compositing-inverse alpha)
into the `--primitive-{role}-*` (+ `--color-{role}-contrast`) override map.
seed -> { variables, roles }. No DOM. 6 tests.
- ActiveEidos.applyColorScheme(seed, opts) / clearColorScheme(): resolves donor
scales + background from the active theme, writes a managed `uix-eidos-scheme`
style block AFTER the theme block (wins the cascade), and RE-DERIVES on mode
change (follows light/dark). Returns BuildSchemeResult for introspection. opts:
variant (tonal|vibrant|monochrome) + temper (intent coherence, keeps hue) +
per-role overrides + selector. 4 tests (return value, intents, DOM block
ordering + clear, mode re-derivation).
- index.ts: export buildScheme + ApplyColorSchemeOptions + BuildScheme* types.
- temas/color demo: themeOverride now dogfoods buildScheme (drops the duplicated
emitRole/rgbaStr; identical output verified in-browser).
- generated/base.css: regenerated for the loss->plum role fix (binding layer
--primitive-loss-* now points at --scale-plum-*; keeps the contract test green).
- docs: THEMING.md SS26 + COLOR_ENGINE_RFC SS6.2 (status: landed) + README ref row.
Overriding the binding layer reprojects every --color-{role}-{slot} + the neutral
chrome downstream; the 31-scale palette stays put. Math in $color, composition in
eidos/lib (pure), DOM application in ActiveEidos.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>