Animation Pipeline: Main Thread to Compositor
Blink28625 Syys 2025

Animation Pipeline: Main Thread to Compositor

The sources provide an extensive architectural overview of the Chromium animation pipeline, detailing the complex process required to accelerate animations by moving them off the main thread onto the compositor thread (cc). The explanation outlines the flow, starting when an animation is initiated in the Blink renderer via classes like Animation and KeyframeEffect, especially if the animation targets compositor-capable properties like transform or opacity. This main thread state is prepared for transfer during the PreCommit phase, where the main thread's AnimationHost creates corresponding compositor objects. The sources then explain the Commit process, where the CommitState structure facilitates the safe synchronization of this animation data to the compositor thread's AnimationHost and ElementAnimations object. Finally, the text describes how animations run on the compositor, ticking every frame and applying values directly to the property trees before sending synchronization events back to Blink regarding start and completion times.

Jaksot(394)

Blink's Graph Data Structures and Traversals

Blink's Graph Data Structures and Traversals

The text provides an extensive overview of the graph-structured data structures used within Blink, Chromium's rendering engine, detailing how web content is processed from initial input to final displ...

13 Loka 202539min

blink::PropertyTreeManager

blink::PropertyTreeManager

bridges Blink property trees → cc property trees. Given Blink’s Transform/Clip/Effect/Scroll nodes (from paint property trees), this class creates/updates the cc counterparts (cc::TransformNode, cc::C...

10 Loka 202546min

blink::PaintArtifactCompositor

blink::PaintArtifactCompositor

turns chunks into compositor layers & updates cc property trees. Consumes the new PaintArtifact and does the layerization and property‑tree updates required for compositor draw. It supports fast paths...

10 Loka 202529min

blink::PaintChunk and blink::DisplayItemList

blink::PaintChunk and blink::DisplayItemList

grouping and content. PaintChunk: groups sequential display items that share the same property‑tree state and cull/visibility; it’s the unit we layerize and invalidate.DisplayItemList: the recorded Sk...

10 Loka 202537min

blink::PaintArtifact

blink::PaintArtifact

the immutable “what to draw” package for this frame. A PaintArtifact is the product of Blink painting: a DisplayItemList plus an ordered vector of PaintChunks. It is immutable post‑creation and design...

10 Loka 202531min

blink::PaintController

blink::PaintController

builds the display list + paint chunks and manages caching. As painters call into GraphicsContext, they also drive a PaintController which groups drawing into display items and paint chunks (each keye...

10 Loka 202529min

blink::GraphicsContext

blink::GraphicsContext

immediate drawing API that records to a display list. Painters for layout objects use GraphicsContext to “draw”—but in modern Blink those calls get recorded into a display list (PaintRecord) backed by...

10 Loka 202544min

blink::TransformPaintPropertyNode / ClipPaintPropertyNode / EffectPaintPropertyNode / ScrollPaintPropertyNode

blink::TransformPaintPropertyNode / ClipPaintPropertyNode / EffectPaintPropertyNode / ScrollPaintPropertyNode

These are the nodes within those four trees. Every piece of painted content (a “paint chunk”) is associated with a tuple of (Transform, Clip, Effect, Scroll) nodes—its PropertyTreeState. This precisel...

10 Loka 202533min