WebGLRenderingContext: compressedTexImage2D() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The compressedTexImage2D() method of the WebGLRenderingContext interface of the WebGL API specifies a two-dimensional texture image in a compressed format.

Compressed image formats must be enabled by WebGL extensions before using these methods.

Syntax

// WebGL 1:
compressedTexImage2D(target, level, internalformat, width, height, border)
compressedTexImage2D(target, level, internalformat, width, height, border, pixels)

// Additionally available in WebGL 2:
// read from buffer bound to gl.PIXEL_UNPACK_BUFFER
compressedTexImage2D(target, level, internalformat, width, height, border, imageSize, offset)
compressedTexImage2D(target, level, internalformat, width, height, border, srcData)
compressedTexImage2D(target, level, internalformat, width, height, border, srcData, srcOffset)
compressedTexImage2D(target, level, internalformat, width, height, border, srcData, srcOffset, srcLengthOverride)

Parameters

target

A GLenum specifying the binding point (target) of the active texture. Possible values for compressedTexImage2D:

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 n-th mipmap reduction level.

internalformat

A GLenum specifying the compressed image format. Compressed image formats must be enabled by WebGL extensions before using this method. All values are possible for compressedTexImage2D. 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_etc1 extension:
- ext.COMPRESSED_RGB_ETC1_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_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

width

A GLsizei specifying the width of the texture.

height

A GLsizei specifying the height of the texture.

depth

A GLsizei specifying the depth of the texture/the number of textures in a TEXTURE_2D_ARRAY.

border

A GLint specifying the width of the border. Must be 0.

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

A TypedArray or a DataView that will be used as a data store for the compressed image data in memory.

Return value

None (undefined).

Examples

const ext =
  gl.getExtension("WEBGL_compressed_texture_s3tc") ||
  gl.getExtension("MOZ_WEBGL_compressed_texture_s3tc") ||
  gl.getExtension("WEBKIT_WEBGL_compressed_texture_s3tc");

const texture = gl.createTexture();
gl.bindTexture(gl.TEXTURE_2D, texture);
gl.compressedTexImage2D(
  gl.TEXTURE_2D,
  0,
  ext.COMPRESSED_RGBA_S3TC_DXT5_EXT,
  512,
  512,
  0,
  textureData,
);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR);
gl.texParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR);

Specifications

Specification
WebGL Specification # COMPRESSEDTEXIMAGE2D

Browser compatibility

BCD tables only load in the browser