WEBGL_compressed_texture_etc1 extension

{{APIRef("WebGL")}}

The WEBGL_compressed_texture_etc1 extension is part of the WebGL API and exposes the ETC1 compressed texture format.

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 {{domxref("WebGLRenderingContext.getExtension()")}} method. For more information, see also Using Extensions in the WebGL tutorial.

[!NOTE] This extension is available to both, {{domxref("WebGLRenderingContext", "WebGL1", "", 1)}} and {{domxref("WebGL2RenderingContext", "WebGL2", "", 1)}} contexts.

Constants

The compressed texture format is exposed by a constant and can be used with the {{domxref("WebGLRenderingContext.compressedTexImage2D", "compressedTexImage2D()")}} method (note that ETC1 is not supported with the {{domxref("WebGLRenderingContext.compressedTexSubImage2D", "compressedTexSubImage2D()")}} method).

• ext.COMPRESSED_RGB_ETC1_WEBGL
  • : Compresses 24-bit RGB data with no alpha channel.

Examples

const ext = gl.getExtension("WEBGL_compressed_texture_etc1");

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

gl.compressedTexImage2D(
  gl.TEXTURE_2D,
  0,
  ext.COMPRESSED_RGB_ETC1_WEBGL,
  512,
  512,
  0,
  textureData,
);

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• Ericsson Texture Compression – Wikipedia
• {{domxref("WEBGL_compressed_texture_etc")}} (ETC2 and EAC)
• {{domxref("WebGLRenderingContext.getExtension()")}}
• {{domxref("WebGLRenderingContext.compressedTexImage2D()")}}
• {{domxref("WebGLRenderingContext.getParameter()")}}