cc Transform and Scroll Trees
Blink28628 Syys 2025

cc Transform and Scroll Trees

The source text details the architecture of Chromium's compositor, focusing on the tandem operation of two critical data structures: the Transform Tree and the Scroll Tree. The Transform Tree manages visual coordinate space transformations, including CSS transforms and scroll offsets, with each TransformNode calculating its final position relative to its parent using local matrices and the scroll translation. In parallel, the Scroll Tree, composed of ScrollNodes, handles the logical state of scrollable elements, defining constraints like scrollable bounds, allowed directions, and scroll chaining behavior. Crucially, the sources explain that the two trees are linked via a shared ElementId and that while the Scroll Tree determines how a scroll should happen (bounds and policy), the Transform Tree executes the change by holding and applying the live scroll_offset to visually move the layer content, enabling smooth, composite-threaded scrolling.

Jaksot(417)

Blink's ComputedStyle: An In-Depth Analysis

Blink's ComputedStyle: An In-Depth Analysis

The collection of sources provides a detailed technical analysis of the ComputedStyle object within Blink, the rendering engine for Chromium. The primary source, an in-depth analysis document, explain...

9 Loka 202545min

Chromium LayerContext Deep Dive: RenderingNG and Scroll Updates

Chromium LayerContext Deep Dive: RenderingNG and Scroll Updates

The source material, primarily an excerpt from a 2025 technical report, provides an in-depth analysis of the LayerContext abstraction within the Chromium RenderingNG pipeline, specifically when the br...

8 Loka 202532min

[ext] Blink's Paint Property Tree Builder: A Surgical Tour of Dragons

[ext] Blink's Paint Property Tree Builder: A Surgical Tour of Dragons

(Make it over 20000 words) source text provides an extremely detailed, technical overview of the blink::PaintPropertyTreeBuilder class in Chromium, which is responsible for building the rendering pipe...

7 Loka 20251h 36min

Blink's Paint Property Tree Builder: A Surgical Tour of Dragons

Blink's Paint Property Tree Builder: A Surgical Tour of Dragons

The source text provides an extremely detailed, technical overview of the blink::PaintPropertyTreeBuilder class in Chromium, which is responsible for building the rendering pipeline's four synchronize...

7 Loka 202543min

Chrome Compositor LayerTree Architecture and Input Handling

Chrome Compositor LayerTree Architecture and Input Handling

The text provides a detailed overview of the architecture and function of Chrome's Compositor (cc) component, specifically focusing on the core data structures: LayerTree and LayerTreeImpl. It explain...

7 Loka 202527min

viz::Display::DrawAndSwap

viz::Display::DrawAndSwap

In Chrome’s rendering pipeline, the Viz service in the GPU process owns a viz::Display object. A Display is responsible for taking aggregated CompositorFrames (produced by the SurfaceAggregator), draw...

5 Loka 202528min

Chrome RenderingNG: Paint Artifact and Compositor Architecture

Chrome RenderingNG: Paint Artifact and Compositor Architecture

source provides an extensive, lecture-style examination of Chrome’s RenderingNG pipeline, specifically focusing on the roles of the PaintArtifact and the PaintArtifactCompositor. The text explains tha...

5 Loka 202534min

Browser Rendering: Calculating Draw Properties

Browser Rendering: Calculating Draw Properties

The source provides an extensive explanation of the internal browser rendering mechanism used in Blink and Chrome, specifically focusing on the CalculateDrawProperties algorithm. This process translat...

5 Loka 202539min