Chrome Compositor Transform Updates on Scroll
Blink2864 Loka 2025

Chrome Compositor Transform Updates on Scroll

These sources provide an extensive technical explanation of how the Chrome compositor manages dynamic properties, specifically focusing on transformations and scrolling, using a structure called PropertyTrees. The core mechanism for efficiency relies on granular dirty state propagation: when a property changes (like a scroll offset or animation), only the affected TransformNodes are marked as dirty (needs_local_transform_update) rather than forcing a full re-evaluation of the entire scene. The process, governed by UpdateTransformTree, ensures that changes—including complex interactions like elastic overscroll, fixed/sticky positioning, and pinch-zoom—are translated into updated screen-space layer matrices (transforms) by traversing only the dependent edges, thereby minimizing computational cost during each render frame. The sources clarify the tight coordination between the ScrollTree (which tracks offsets) and the TransformTree (which incorporates those offsets into actual layer movement matrices).


Jaksot(396)

[EXPERT] The PaintLayer Tree in Blink Rendering

[EXPERT] The PaintLayer Tree in Blink Rendering

The provided text explains the PaintLayer tree, an internal architectural component of Google Chrome’s Blink rendering engine that manages complex visual tasks. PaintLayers are selectively created for...

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CSS Sticky Positioning and Paint Property Trees

CSS Sticky Positioning and Paint Property Trees

This documentation details how the Blink rendering engine manages CSS sticky positioning through its PrePaint and paint property tree workflows. During the PrePaint phase, the engine identifies sticky...

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[General] Inside Blink: The Paint Property Tree Builder Pipeline

[General] Inside Blink: The Paint Property Tree Builder Pipeline

The PaintPropertyTreeBuilder is a critical component within Google Chrome’s Blink engine that converts layout data into structural property trees used for rendering. Operating during the PrePaint phas...

24 Joulu 202550min

Inside Blink: The Paint Property Tree Builder Pipeline

Inside Blink: The Paint Property Tree Builder Pipeline

The PaintPropertyTreeBuilder is a critical component within Google Chrome’s Blink engine that converts layout data into structural property trees used for rendering. Operating during the PrePaint phas...

24 Joulu 20251h 4min

Promisify Scroll: Promise-Based Web Scrolling API

Promisify Scroll: Promise-Based Web Scrolling API

The provided text describes a web platform initiative to modernize how browsers handle scrolling by having programmatic scroll methods return JavaScript Promises. Currently, functions like scrollTo() ...

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CSS Containing Blocks and Blink Engine Implementation

CSS Containing Blocks and Blink Engine Implementation

This text examines how CSS containing blocks function and how the Blink rendering engine implements these rules within Chromium. It explains that a containing block is the essential rectangular refere...

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Axis-Split Sticky Constraints in Chromium Layout and Compositing

Axis-Split Sticky Constraints in Chromium Layout and Compositing

Chromium is refining its rendering engine to support axis-split sticky constraints, allowing elements to stick to different scroll containers for horizontal and vertical movements. Previously, a singl...

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Mastering CSS Sticky Positioning and Scroll Containers

Mastering CSS Sticky Positioning and Scroll Containers

This documentation provides a comprehensive analysis of CSS sticky positioning, a hybrid layout scheme that anchors elements within their nearest scroll container while maintaining their space in the ...

20 Joulu 202534min