FragmentPaintPropertyTreeBuilder::UpdateScrollAndScrollTranslation()
Blink28618 Loka 2025

FragmentPaintPropertyTreeBuilder::UpdateScrollAndScrollTranslation()

The provided sources offer an extensive, line-by-line analysis of Blink’s rendering function, FragmentPaintPropertyTreeBuilder::UpdateScrollAndScrollTranslation(), which is critical for implementing scrolling behavior in Chrome. This function manages the creation and updating of two primary data structures: the Scroll Property Node (which defines the logical scroll container, including its viewport, content size, and CSS properties like overscroll behavior and scroll snapping) and the Scroll Translation Transform Node (which applies the negative scroll offset as a geometric translation to descendant content). The process is part of RenderingNG, which uses separate property trees (Transform, Clip, Effect, Scroll) to achieve efficient, incremental updates. The method ensures that only scrollable objects receive these nodes, updates related scrollbar Effect Nodes, and implements optimizations like directly updating the compositor's transform for simple scroll offset changes without rebuilding the entire paint artifact.

Jaksot(408)

Hybrid Overscroll: Root Glow and Inner Bounce in WebView

Hybrid Overscroll: Root Glow and Inner Bounce in WebView

The provided text details the complex mechanisms governing overscroll behavior within the Android WebView and Chromium engine, specifically contrasting how the root content and non-root scrollable ele...

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WebView Feature Flags: Java to Native Compositor

WebView Feature Flags: Java to Native Compositor

The source documents examine the complex, multi-layered feature-flag architecture within Android's WebView, which is essential for controlling experimental features, field trials (Finch), and underlyi...

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Geometry, Immutability, and Caching in LayoutNG Fragments

Geometry, Immutability, and Caching in LayoutNG Fragments

The provided text describes Blink’s LayoutNG Fragment Tree, an immutable structure that captures the final geometry and layout results, replacing the mutable legacy layout tree. This structure is comp...

4 Joulu 20251h 5min

The CSS anchor-scope Property: Design and Blink Layout

The CSS anchor-scope Property: Design and Blink Layout

The provided text exhaustively describes the CSS anchor-scope property, a critical addition to CSS Anchor Positioning designed to prevent naming conflicts when reusing components. This property define...

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The Bicameral Mind and the Birth of Consciousness

The Bicameral Mind and the Birth of Consciousness

The provided text offers a comprehensive exploration of Julian Jaynes's Bicameral Mind Theory, which posits that humans, as recently as 3,000 years ago, lacked modern introspective consciousness. Jayn...

3 Joulu 202559min

Trees in Viz: Chrome's Centralized Compositing Engine

Trees in Viz: Chrome's Centralized Compositing Engine

The source details a significant re-architecture of the Chromium rendering pipeline, known as JellyMander, centered on the feature Trees in Viz (TiV). This change shifts the core task of frame composi...

30 Marras 202530min

PaintLayerPainter: Blink's Bridge from Layout to Rendering

PaintLayerPainter: Blink's Bridge from Layout to Rendering

The source material provides an exhaustive technical analysis of Blink’s PaintLayerPainter, the central coordinator responsible for executing the CSS painting algorithm to generate visual output. This...

30 Marras 202541min

Blink Property Trees: Scene Graph for Compositing

Blink Property Trees: Scene Graph for Compositing

The sources provide a comprehensive technical analysis of the Paint Property Tree Builder (PPTB) in Blink, which is the mechanism responsible for creating the crucial intermediate data structures know...

30 Marras 202540min