Chrome Compositor Animation Architecture (cc)
Blink28615 Okt 2025

Chrome Compositor Animation Architecture (cc)

The sources provide an extensive architectural overview of the Chrome Compositor Animation (cc) subsystem, which is responsible for executing visual animations like transforms and opacity changes efficiently. This architecture relies on a dual-thread model, where the main thread prepares animation data, but the actual animation ticking, interpolation, and property updates happen on the dedicated compositor thread (impl thread) to ensure smooth, "hitch-free" rendering independent of main thread activity. Key components described include the AnimationHost, which coordinates animations on each thread, and the hierarchy of classes—Animation, KeyframeEffect, and KeyframeModel—that represent the animated properties and their curves. The sources detail the synchronization lifecycle of animations from creation on the main thread through the commit process to continuous per-frame ticking on the impl thread, while also distinguishing compositor-accelerated animations from those that must run on the main thread. Finally, the text explores performance strategies like GPU acceleration, frame rate synchronization, and support for modern features such as Scroll-Linked Animations and the Animation Worklet API.

Episoder(396)

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 Okt 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 Okt 202533min

blink::PaintPropertyTreeBuilder

blink::PaintPropertyTreeBuilder

builds/updates paint property trees.Consumes the layout/fragment data and produces the four paint property trees (Transform, Clip, Effect, Scroll) for the current frame. These trees encode coordinate ...

10 Okt 202547min

blink::PrePaintTreeWalk

blink::PrePaintTreeWalk

cross‑frame pre‑paint traversal. Runs in the InPrePaint lifecycle phase. Walks the entire layout tree starting at the root LocalFrameView, updating paint invalidation state and computing the context n...

10 Okt 202531min

blink::NGPhysicalFragment and friends

blink::NGPhysicalFragment and friends

Layout takes the styled DOM and produces a fragment tree of positioned boxes. In modern Blink this is LayoutNG; the core artifact is NGPhysicalFragment, which stores geometry and is used downstream fo...

10 Okt 202537min

blink::StyleEngine

blink::StyleEngine

style invalidation & resolution (recalc). 
Given DOM/style changes since the last frame, StyleEngine computes updated ComputedStyles, manages active stylesheets/media query state, and marks the right ...

10 Okt 202534min

blink::Document & blink::DocumentLifecycle

blink::Document & blink::DocumentLifecycle

states that gate phases. The document owns the DOM and keeps a DocumentLifecycle state machine that ensures we do things in phase order (style before layout, pre‑paint before paint, etc.). Lifecycle t...

10 Okt 202535min

blink::LocalFrameView

blink::LocalFrameView

orchestrates style → layout → pre‑paint/paint for a frame. This is the workhorse that actually runs lifecycle phases. On a frame tick from WebFrameWidgetImpl, it goes through style recalc, layout (Lay...

9 Okt 202544min

Populært innen Teknologi

lydartikler-fra-aftenposten
romkapsel
tomprat-med-gunnar-tjomlid
rss-avskiltet
nasjonal-sikkerhetsmyndighet-nsm
smart-forklart
teknisk-sett
energi-og-klima
shifter
rss-impressions-2
elektropodden
rss-alt-vi-kan
teknologi-og-mennesker
pedagogisk-intelligens
hans-petter-og-co
rss-ki-praten
kunstig-intelligens-med-morten-goodwin
rss-fjorsilkebris-podcast
rss-bouvet-bobler
rss-alt-som-gar-pa-strom