Web/API/WebGLRenderingContext/compressedTexSubImage2D

The WebGLRenderingContext.compressedTexSubImage2D() method of the WebGL API specifies a two-dimensional sub-rectangle for a texture image in a compressed format.

Compressed image formats must be enabled by WebGL extensions before using this method or a WebGL2RenderingContext must be used.

Syntax

// WebGL 1:
void gl.compressedTexSubImage2D(target, level, xoffset, yoffset, width, height, format, ArrayBufferView? pixels);

// Additionally available in WebGL 2:
void gl.compressedTexSubImage2D(target, level, xoffset, yoffset, width, height, format, imageSize, offset); 
void gl.compressedTexSubImage2D(target, level, xoffset, yoffset, width, height, format, ArrayBufferView srcData, optional srcOffset, optional srcLengthOverride);

Parameters

target: A GLenum specifying the binding point (target) of the active compressed texture. Possible values:

gl.TEXTURE_2D

A two-dimensional texture.
gl.TEXTURE_CUBE_MAP_POSITIVE_X: Positive X face for a cube-mapped texture.
gl.TEXTURE_CUBE_MAP_NEGATIVE_X: Negative X face for a cube-mapped texture.
gl.TEXTURE_CUBE_MAP_POSITIVE_Y: Positive Y face for a cube-mapped texture.
gl.TEXTURE_CUBE_MAP_NEGATIVE_Y: Negative Y face for a cube-mapped texture.
gl.TEXTURE_CUBE_MAP_POSITIVE_Z: Positive Z face for a cube-mapped texture.
gl.TEXTURE_CUBE_MAP_NEGATIVE_Z: Negative Z face for a cube-mapped texture.

level: A GLint specifying the level of detail. Level 0 is the base image level and level n is the nth mipmap reduction level.
xoffset: A GLint specifying the horizontal offset within the compressed texture image.
yoffset: A GLint specifying the vertical offset within the compressed texture image.
width: A GLsizei specifying the width of the compressed texture.
height: A GLsizei specifying the height of the compressed texture.
format: A GLenum specifying the compressed image format. Compressed image formats must be enabled by WebGL extensions before using this method. Possible values:

When using the WEBGL_compressed_texture_s3tc extension

ext.COMPRESSED_RGB_S3TC_DXT1_EXT ext.COMPRESSED_RGBA_S3TC_DXT1_EXT ext.COMPRESSED_RGBA_S3TC_DXT3_EXT ext.COMPRESSED_RGBA_S3TC_DXT5_EXT

When using the WEBGL_compressed_texture_s3tc_srgb extension

ext.COMPRESSED_SRGB_S3TC_DXT1_EXT ext.COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT ext.COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT ext.COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT

When using the WEBGL_compressed_texture_etc extension

ext.COMPRESSED_R11_EAC ext.COMPRESSED_SIGNED_R11_EAC ext.COMPRESSED_RG11_EAC ext.COMPRESSED_SIGNED_RG11_EAC ext.COMPRESSED_RGB8_ETC2 ext.COMPRESSED_RGBA8_ETC2_EAC ext.COMPRESSED_SRGB8_ETC2 ext.COMPRESSED_SRGB8_ALPHA8_ETC2_EAC ext.COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2 ext.COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2

When using the WEBGL_compressed_texture_pvrtc extension

ext.COMPRESSED_RGB_PVRTC_4BPPV1_IMG ext.COMPRESSED_RGBA_PVRTC_4BPPV1_IMG ext.COMPRESSED_RGB_PVRTC_2BPPV1_IMG ext.COMPRESSED_RGBA_PVRTC_2BPPV1_IMG

When using the WEBGL_compressed_texture_atc extension

ext.COMPRESSED_RGB_ATC_WEBGL ext.COMPRESSED_RGBA_ATC_EXPLICIT_ALPHA_WEBGL ext.COMPRESSED_RGBA_ATC_INTERPOLATED_ALPHA_WEBGL

When using the WEBGL_compressed_texture_astc extension

ext.COMPRESSED_RGBA_ASTC_4x4_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR ext.COMPRESSED_RGBA_ASTC_5x4_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR ext.COMPRESSED_RGBA_ASTC_5x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR ext.COMPRESSED_RGBA_ASTC_6x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR ext.COMPRESSED_RGBA_ASTC_6x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR ext.COMPRESSED_RGBA_ASTC_8x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR ext.COMPRESSED_RGBA_ASTC_8x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR ext.COMPRESSED_RGBA_ASTC_8x8_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR ext.COMPRESSED_RGBA_ASTC_10x5_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR ext.COMPRESSED_RGBA_ASTC_10x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR ext.COMPRESSED_RGBA_ASTC_10x6_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR ext.COMPRESSED_RGBA_ASTC_10x10_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR ext.COMPRESSED_RGBA_ASTC_12x10_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR ext.COMPRESSED_RGBA_ASTC_12x12_KHR ext.COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR

When using the EXT_texture_compression_bptc extension

ext.COMPRESSED_RGBA_BPTC_UNORM_EXT ext.COMPRESSED_SRGB_ALPHA_BPTC_UNORM_EXT ext.COMPRESSED_RGB_BPTC_SIGNED_FLOAT_EXT ext.COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_EXT

When using the EXT_texture_compression_rgtc extension

ext.COMPRESSED_RED_RGTC1_EXT ext.COMPRESSED_SIGNED_RED_RGTC1_EXT ext.COMPRESSED_RED_GREEN_RGTC2_EXT ext.COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT

imageSize: A GLsizei specifying the number of bytes to read from the buffer bound to gl.PIXEL_UNPACK_BUFFER.
offset: A GLintptr specifying the offset in bytes from which to read from the buffer bound to gl.PIXEL_UNPACK_BUFFER.
pixels: An ArrayBufferView that be used as a data store for the compressed image data in memory.

Return value

None.

Examples

var ext = (
  gl.getExtension('WEBGL_compressed_texture_s3tc') ||
  gl.getExtension('MOZ_WEBGL_compressed_texture_s3tc') ||
  gl.getExtension('WEBKIT_WEBGL_compressed_texture_s3tc')
);
gl.compressedTexSubImage2D(gl.TEXTURE_2D, 0, 256, 256, 512, 512, ext.COMPRESSED_RGBA_S3TC_DXT5_EXT, textureData);

Specifications

Specification	Status	Comment
WebGL 1.0The definition of 'compressedTexSubImage2D' in that specification.	Recommendation	Initial definition for WebGL.
OpenGL ES 2.0The definition of 'glCompressedTexSubImage2D' in that specification.	Standard	Man page of the (similar) OpenGL ES 2.0 API.
OpenGL ES 3.0The definition of 'glCompressedTexSubImage2D' in that specification.	Standard	Man page of the (similar) OpenGL ES 3.0 API.

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
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`compressedTexSubImage2D`	Chrome Full support 9	Edge Full support 12	Firefox Full support 4	IE Full support 11	Opera Full support 12	Safari Full support 5.1	WebView Android Full support Yes	Chrome Android Full support 25	Firefox Android Full support Yes	Opera Android Full support 12	Safari iOS Full support 8	Samsung Internet Android Full support 1.5
`WebGL2`	Chrome Full support 56	Edge Full support 79	Firefox Full support 51	IE No support No	Opera Full support 43	Safari No support No	WebView Android Full support 58	Chrome Android Full support 58	Firefox Android Full support 51	Opera Android Full support 43	Safari iOS No support No	Samsung Internet Android Full support 7.0

Legend

Full support: Full support
No support: No support