Chrome's CSS Scroll Snap Implementation: Blink and Compositor Deep Dive
Blink28629 Loka 2025

Chrome's CSS Scroll Snap Implementation: Blink and Compositor Deep Dive

The source provides an extensive technical explanation of the implementation of CSS Scroll Snap within the Google Chrome browser, specifically detailing how the feature is managed across the Blink rendering engine and the Chromium Compositor (CC). It begins by outlining the historical evolution of scroll snapping from early coordinate-based specifications to the modern element-based model, which uses properties like scroll-snap-type and scroll-snap-align. The text then describes the division of labor: Blink handles the interpretation of CSS and calculates precise snap coordinates (SnapContainerData), while the Compositor thread utilizes this data along with various SnapSelectionStrategy objects to manage smooth scroll animations, handle user input, and ensure correct snapping behavior (including managing the 50% proximity threshold and scroll-snap-stop priority). Finally, the document discusses future developments for the feature, such as the introduction of scroll snap events and potential fine-grained control for developers.


Jaksot(394)

Upward Propagation Mechanisms in Blink LayoutNG

Upward Propagation Mechanisms in Blink LayoutNG

The provided text explains how Chromium’s LayoutNG engine utilizes upward propagation to transfer critical layout data from child elements to their ancestors. By aggregating information such as intrin...

31 Joulu 202528min

Blink Sticky Positioning: Constraint Updates and Paint Invalidation

Blink Sticky Positioning: Constraint Updates and Paint Invalidation

The provided documentation details how the Blink rendering engine manages sticky positioning through specific methods within the PaintLayerScrollableArea class. It explains that the system first calcu...

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Blink’s Scrolling Engine: The PaintLayerScrollableArea Deep Dive

Blink’s Scrolling Engine: The PaintLayerScrollableArea Deep Dive

The provided text explains the PaintLayerScrollableArea, a central component within the Blink rendering engine that manages scrolling for web elements and viewports. It describes how this object bridg...

30 Joulu 202531min

Understanding PropagatedData in Blink’s LayoutNG Fragment Tree

Understanding PropagatedData in Blink’s LayoutNG Fragment Tree

In Blink’s LayoutNG engine, PropagatedData serves as a specialized, light-weight container used to carry critical layout information upward through the fragment tree. This garbage-collected object is ...

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Self-Painting Layers in Blink: Architecture and Implementation Decisions

Self-Painting Layers in Blink: Architecture and Implementation Decisions

In the Blink rendering engine, PaintLayers form a specialized hierarchy used to manage the visual assembly of a webpage, separate from the standard layout tree. These layers are created for elements r...

30 Joulu 202539min

[EXTENDED] PaintLayer Parent Hierarchies in the Blink Rendering Engine

[EXTENDED] PaintLayer Parent Hierarchies in the Blink Rendering Engine

In the Blink rendering engine, the PaintLayer system utilizes multiple hierarchical relationships to manage how web content is displayed and organized. While the structural parent defines the primary ...

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PaintLayer Parent Hierarchies in the Blink Rendering Engine

PaintLayer Parent Hierarchies in the Blink Rendering Engine

The provided text details the Blink rendering engine’s PaintLayer system, specifically focusing on the complex "parent" hierarchies used to manage web page display. It explains that while the structur...

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Blink PrePaint: Fragment Traversal and Paint Property Tree Construction

Blink PrePaint: Fragment Traversal and Paint Property Tree Construction

The provided text explains the PrePaint phase within Blink’s rendering engine, a critical stage where the system prepares for visual output by invalidating old paint and building property trees. Durin...

29 Joulu 202559min