coderef

EXT_texture_compression_rgtc WebGL extensionBaseline · Newly available

The EXT_texture_compression_rgtc extension for WebGL 1.0 and 2.0 contexts adds RGTC compressed texture formats. RGTC is a block-based texture compression format suited for unsigned and signed red and red-green textures. Also known as Red-Green Texture Compression.

Works in the latest version of every major browser, but older devices may not support it yet. Baseline since May 12, 2025.

How to use ↓Compare browsers

Browser support

DesktopChrome
1–92Not supported
93+Supportedsince Aug 31, 2021
Current: 155
Edge
12–92Not supported
93+Supportedsince Sep 2, 2021
Current: 154
Firefox
1–64Not supported
65+Supportedsince Jan 29, 2019
Current: 157
Safari
1–14Not supported
14.1+Supportedsince Apr 26, 2021
Current: 27
MobileChrome Android
18–81Not supported
83+Supportedsince May 19, 2020
Current: 155
Firefox Android
4–64Not supported
65+Supportedsince Jan 29, 2019
Current: 157
Safari iOS
1–18.4Not supported
18.5+Supportedsince May 12, 2025
Current: 27

How to use

Every current browser supports this, but it only became Baseline on May 12, 2025. Use it as a progressive enhancement, or keep a fallback if you support older devices.

Example

Full syntax and examples are on MDN: EXT texture compression rgtc.

Feature detection

JS · check before using
if ("EXT_texture_compression_rgtc" in globalThis) {
  // EXT_texture_compression_rgtc is available
} else {
  // load a polyfill or use a fallback
}

Documentation (MDN)

Specification