The WEBGL_compressed_texture_astc
extension is part of the WebGL API and exposes Adaptive Scalable Texture Compression (ASTC) compressed texture formats to WebGL.
For more information, see the article Using ASTC Texture Compression for Game Assets by nvidia.
WebGL extensions are available using the WebGLRenderingContext.getExtension()
method. For more information, see also Using Extensions in the WebGL tutorial.
Availability: ASTC compression is typically available on Mali ARM GPUs, Intel GPUs, and Nividia Tegra chips.
This extension is available to both, WebGL1 and WebGL2 contexts.
Methods
This extension exposes one new methods.
ext.getSupportedProfiles()
- Returns an array of strings containing the names of the ASTC profiles supported by the implementation.
Constants
The compressed texture formats are exposed by 28 constants and can be used in two functions: compressedTexImage2D()
and compressedTexSubImage2D()
.
Constants | Blocks | Bits per pixel | ArrayBuffer byteLength
|
bytes if height and width are 512 |
ext.COMPRESSED_RGBA_ASTC_4x4_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR
|
4x4 | 8.00 | floor((width + 3) / 4) * floor((height + 3) / 4) * 16
|
262144 |
ext.COMPRESSED_RGBA_ASTC_5x4_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR
|
5x4 | 6.40 | floor((width + 4) / 5) * floor((height + 3) / 4) * 16
|
210944 |
ext.COMPRESSED_RGBA_ASTC_5x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR
|
5x5 | 5.12 | floor((width + 4) / 5) * floor((height + 4) / 5) * 16
|
169744 |
ext.COMPRESSED_RGBA_ASTC_6x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR
|
6x5 | 4.27 | floor((width + 5) / 6) * floor((height + 4) / 5) * 16
|
141728 |
ext.COMPRESSED_RGBA_ASTC_6x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR
|
6x6 | 3.56 | floor((width + 5) / 6) * floor((height + 5) / 6) * 16
|
118336 |
ext.COMPRESSED_RGBA_ASTC_8x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR
|
8x5 | 3.20 | floor((width + 7) / 8) * floor((height + 4) / 5) * 16
|
105472 |
ext.COMPRESSED_RGBA_ASTC_8x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR
|
8x6 | 2.67 | floor((width + 7) / 8) * floor((height + 5) / 6) * 16
|
88064 |
ext.COMPRESSED_RGBA_ASTC_8x8_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR
|
8x8 | 2.00 | floor((width + 7) / 8) * floor((height + 7) / 8) * 16
|
65536 |
ext.COMPRESSED_RGBA_ASTC_10x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR
|
10x5 | 2.56 | floor((width + 9) / 10) * floor((height + 4) / 5) * 16
|
85696 |
ext.COMPRESSED_RGBA_ASTC_10x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR
|
10x6 | 2.13 | floor((width + 9) / 10) * floor((height + 5) / 6) * 16
|
71552 |
ext.COMPRESSED_RGBA_ASTC_10x8_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR
|
10x8 | 1.60 | floor((width + 9) / 10) * floor((height + 7) / 8) * 16
|
53248 |
ext.COMPRESSED_RGBA_ASTC_10x10_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR
|
10x10 | 1.28 | floor((width + 9) / 10) * floor((height + 9) / 10) * 16
|
43264 |
ext.COMPRESSED_RGBA_ASTC_12x10_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR
|
12x10 | 1.07 | floor((width + 11) / 12) * floor((height + 9) / 10) * 16
|
35776 |
ext.COMPRESSED_RGBA_ASTC_12x12_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR
|
12x12 | 0.89 | floor((width + 11) / 12) * floor((height + 11) / 12) * 16
|
29584 |
Examples
var ext = gl.getExtension('WEBGL_compressed_texture_astc'); var texture = gl.createTexture(); gl.bindTexture(gl.TEXTURE_2D, texture); gl.compressedTexImage2D(gl.TEXTURE_2D, 0, ext.COMPRESSED_RGBA_ASTC_12x12_KHR, 512, 512, 0, textureData);
Specifications
Specification | Status | Comment |
WEBGL_compressed_texture_astcThe definition of 'WEBGL_compressed_texture_astc' in that specification. | Recommendation | Initial definition. |
Browser compatibility
The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
WEBGL_compressed_texture_astc
|
Chrome
Full support 47 |
Edge
Full support 79 |
Firefox
Full support 53 |
IE
? |
Opera
? |
Safari
? |
WebView Android
Full support 47 |
Chrome Android
Full support 47 |
Firefox Android
Full support 53 |
Opera Android
? |
Safari iOS
? |
Samsung Internet Android
Full support 5.0 |
getSupportedProfiles
|
Chrome
Full support 47 |
Edge
Full support 79 |
Firefox
Full support 53 |
IE
? |
Opera
? |
Safari
? |
WebView Android
Full support 47 |
Chrome Android
Full support 47 |
Firefox Android
Full support 53 |
Opera Android
? |
Safari iOS
? |
Samsung Internet Android
Full support 5.0 |
Legend
- Full support
- Full support
- Compatibility unknown
- Compatibility unknown
See also
- Using ASTC Texture Compression for Game Assets
WebGLRenderingContext.getExtension()
WebGLRenderingContext.compressedTexImage2D()
WebGLRenderingContext.compressedTexSubImage2D()
WebGLRenderingContext.getParameter()
WEBGL_compressed_texture_astc by Mozilla Contributors is licensed under CC-BY-SA 2.5.