Blink's PendingLayer: Bridge Between Paint and Compositor
Blink28615 Marras 2025

Blink's PendingLayer: Bridge Between Paint and Compositor

The document provides an extensive technical overview of the PendingLayer class, a critical internal component within Blink’s Composite After Paint (CAP) architecture. PendingLayer acts as a liaison, aggregating multiple Paint Chunks (painted content units) into a single logical unit that will eventually become a single cc::Layer in the Chromium compositor. The text details the class's structure, including fields for geometry, content references, and Compositing Type, and describes its transient lifecycle during the frame update process led by the PaintArtifactCompositor. Crucially, the document explains the complex layerization heuristics—including property tree compatibility, upcasting, overlap checks, and LCD text preservation—used to minimize the total layer count for improved performance while maintaining visual correctness. Finally, it outlines how this mechanism supports modern optimizations, such as partial repaint fast-paths and scroll unification, by providing stable layer structures across frames.

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LCD Text Rendering – Algorithm, Heuristics & Scroll Raster Impacts

LCD Text Rendering – Algorithm, Heuristics & Scroll Raster Impacts

The source text provides an extensive technical overview of LCD text rendering (subpixel antialiasing) within the Google Chrome browser's architecture, involving the Blink rendering engine and the Ski...

11 Marras 202542min

Compositor-Thread Scrolling – CC Mechanics and Property Trees

Compositor-Thread Scrolling – CC Mechanics and Property Trees

The source provides an extensive technical overview of Chrome’s Compositor-Thread Scrolling architecture, explaining how modern web rendering achieves smooth, low-latency scrolling by handling most sc...

11 Marras 202545min

Blink Main-Thread Scrolling – DOM, Layout, and Lifecycle

Blink Main-Thread Scrolling – DOM, Layout, and Lifecycle

The source provides an extensive technical overview of how the Blink rendering engine handles scrolling, particularly focusing on the main-thread scrolling lifecycle. It explains that while modern bro...

10 Marras 202545min

Architecture of Scrolling in Chrome (Blink vs. CC Overview)

Architecture of Scrolling in Chrome (Blink vs. CC Overview)

The source provides an extensive overview of the Chrome browser's scrolling architecture, detailing the division of labor between the Blink rendering engine (main thread) and the Chromium Compositor (...

10 Marras 202526min

[ext] Web View Transitions: Technical Deep Dive

[ext] Web View Transitions: Technical Deep Dive

The source provides an exhaustive technical and historical overview of the Web View Transition API, a modern set of web platform features designed to enable fluid, animated transitions between user in...

9 Marras 20251h 16min

Chromium Input Handling Deep Dive: Compositor and Proxy

Chromium Input Handling Deep Dive: Compositor and Proxy

The sources provide an extensive examination of Chromium’s input handling pipeline, focusing on the roles of the InputHandler and InputHandlerProxy within the renderer's dedicated compositor thread. T...

8 Marras 202540min

Web View Transitions: Technical Deep Dive

Web View Transitions: Technical Deep Dive

The second source introduces the View Transition API, a modern web platform feature that allows developers to create smooth, animated transitions between different UI states or entire pages by automat...

8 Marras 202547min

Chrome Compositor: Raster-Inducing Scrolling Explained

Chrome Compositor: Raster-Inducing Scrolling Explained

The source provides an extensive technical explanation of raster-inducing scrolling within the Chrome browser's rendering pipeline, focusing on the sophisticated architecture of the Chrome Compositor ...

8 Marras 202542min