CSS View Transition Pseudo-elements Explained
Blink28624 Syys 2025

CSS View Transition Pseudo-elements Explained

These sources provide a detailed, technical explanation of the View Transition API implementation within the Chromium web browser, focusing on how CSS pseudo-elements enable smooth animations. The first source explains that view transition pseudos (like ::view-transition-old() and ::view-transition-new()) are temporary, browser-synthesized overlays used to capture and animate visual snapshots of elements during state changes. The second, more extensive source describes the low-level C++ classes in the Blink rendering engine and the cc compositor that orchestrate this process, including the DocumentTransition class, which manages the lifecycle, snapshot capture, and pseudo-element creation, and the SurfaceAnimationManager in the Viz component, which handles the final, performant GPU-accelerated animation of the saved frames using specialized layers and directives. Together, the texts map the high-level CSS API to the complex, multi-process architecture of Chromium, explaining how old and new content are matched, isolated on the top layer, and composited for animation.


Jaksot(397)

blink::PaintArtifactCompositor

blink::PaintArtifactCompositor

Decides what needs to be composited and prepares the main‑thread representation to feed cc (layers if needed, scrollbar compositing, etc.).

22 Syys 202542min

blink::PaintArtifact

blink::PaintArtifact

The immutable package of paint chunks + display items for this frame, used to drive compositing without re‑painting.

21 Syys 202536min

blink::TransformPaintPropertyNode / ClipPaintPropertyNode / EffectPaintPropertyNode / ScrollPaintPropertyNode

blink::TransformPaintPropertyNode / ClipPaintPropertyNode / EffectPaintPropertyNode / ScrollPaintPropertyNode

The paint property trees captured during painting (transform, clip, effect/opacity, scroll offset) that define visual & coordinate‑space state.

21 Syys 202541min

blink::PaintController

blink::PaintController

Records drawing into a DisplayItemList, segmenting it into PaintChunks keyed by property‑tree state. (Output: a PaintArtifact.)

21 Syys 202533min

blink::LayoutView (root of the layout tree)

blink::LayoutView (root of the layout tree)

Computes geometry for boxes when layout is dirty.

21 Syys 202539min

blink::StyleEngine / style resolver

blink::StyleEngine / style resolver

Recalculates computed styles that changed since last frame (if any).

21 Syys 202542min

blink::Page → blink::LocalFrame / LocalFrameView

blink::Page → blink::LocalFrame / LocalFrameView

The document’s frame & viewport; LocalFrameView is the scrollable root that triggers layout/paint when needed. provided source outlines the fundamental components of the Blink rendering engine, specif...

21 Syys 202539min

blink::WebViewImpl

blink::WebViewImpl

The source text provides an in-depth explanation of the blink::WebViewImpl class within Chromium's Blink rendering engine, characterizing it as the central control point on the renderer's main thread ...

20 Syys 202539min