Late-Bound Paint: The Evolution of Chromium Composited Color

The provided text outlines a strategic architectural proposal for Chromium to transition from a property-specific "composited color" model to a generalized late-bound paint-parameter substrate. Currently, Chromium handles color animations through fragmented, narrow exceptions like native paint-worklets and custom properties, which often rely on re-recording paint rather than updating live values. The author argues for a hybrid approach that uses the existing background-color path as a temporary shipping vehicle while building a more robust system where the compositor provides live parameters during playback. By leveraging patterns from raster-inducing scroll and HDR headroom, the engine could achieve stable recordings that consume dynamic state without constant main-thread invalidation. This shift would resolve existing documentation drift and provide a scalable foundation for handling complex CSS semantics, such as currentColor and text rendering. Ultimately, the source advocates for unifying animation outputs and paint inputs to transform one-off features into a durable rendering capability.