WEBGL_compressed_texture_atc - Web APIs 编辑

The WEBGL_compressed_texture_atc extension is part of the WebGL API and exposes 3 ATC compressed texture formats. ATC is a proprietary compression algorithm for compressing textures on handheld devices.

Compressed textures reduce the amount of memory needed to store a texture on the GPU, allowing for higher resolution textures or more of the same resolution textures.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Availability: ATC compression is typically available on mobile devices with Adreno GPUs, that are currently only built into Qualcomm Snapdragon devices.

This extension is available to both, WebGL1 and WebGL2 contexts.

Constants

The compressed texture formats are exposed by 3 constants and can be used in two functions: compressedTexImage2D() and compressedTexSubImage2D().

ext.COMPRESSED_RGB_ATC_WEBGL

Compresses RGB textures with no alpha channel.

ext.COMPRESSED_RGBA_ATC_EXPLICIT_ALPHA_WEBGL

Compresses RGBA textures using explicit alpha encoding (useful when alpha transitions are sharp).

ext.COMPRESSED_RGBA_ATC_INTERPOLATED_ALPHA_WEBGL

Compresses RGBA textures using interpolated alpha encoding (useful when alpha transitions are gradient).

Examples

var ext = gl.getExtension('WEBGL_compressed_texture_atc');

var texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);

gl.compressedTexImage2D(gl.TEXTURE_2D, 0, ext.COMPRESSED_RGB_ATC_WEBGL, 512, 512, 0, textureData);

Specifications

Browser compatibility

BCD tables only load in the browser

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.

See also

• WebGLRenderingContext.getExtension()
• WebGLRenderingContext.compressedTexImage2D()
• WebGLRenderingContext.compressedTexSubImage2D()
• WebGLRenderingContext.getParameter()