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

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support 9Edge Full support 12Firefox Full support 4IE Full support 11Opera Full support 12Safari Full support 5.1WebView Android Full support YesChrome Android Full support 25Edge Mobile Full support YesFirefox Android Full support YesOpera Android Full support 12Safari iOS Full support 8.1Samsung Internet Android Full support Yes
WebGL2Chrome Full support 56Edge No support NoFirefox Full support 51IE No support NoOpera Full support 43Safari No support NoWebView Android Full support 58Chrome Android Full support 58Edge Mobile No support NoFirefox Android Full support 51Opera Android Full support 43Safari iOS No support NoSamsung Internet Android Full support 7.0

Legend

Full support  
Full support
No support  
No support

See also

Document Tags and Contributors

Contributors to this page: aleonhard, fscholz, nmve, teoli
Last updated by: aleonhard,