glCompressedTexImage3D - OpenGL ES 3.0 Reference Pages

Name

glCompressedTexImage3D — specify a three-dimensional texture image in a compressed format

C Specification

`void glCompressedTexImage3D(`	GLenum `target`,
	GLint `level`,
	GLenum `internalformat`,
	GLsizei `width`,
	GLsizei `height`,
	GLsizei `depth`,
	GLint `border`,
	GLsizei `imageSize`,
	const GLvoid * `data)`;

Parameters

target: Specifies the target texture. Must be GL_TEXTURE_3D, or GL_TEXTURE_2D_ARRAY.
level: Specifies the level-of-detail number. Level 0 is the base image level. Level n is the nth mipmap reduction image.
internalformat: Specifies the format of the compressed image data stored at address data.
width: Specifies the width of the texture image.
height: Specifies the height of the texture image.
depth: Specifies the depth of the texture image.
border: This value must be 0.
imageSize: Specifies the number of unsigned bytes of image data starting at the address specified by data.
data: Specifies a pointer to the compressed image data in memory.

Description

Texturing allows elements of an image array to be read by shaders.

glCompressedTexImage3D loads a previously defined, and retrieved, compressed three-dimensional texture image if target is GL_TEXTURE_3D (see glTexImage3D).

If target is GL_TEXTURE_2D_ARRAY, data is treated as an array of compressed 2D textures.

internalformat must be a compressed image format from Table 1 below, or an extension-specified compressed-texture format.

imageSize must be appropriate for the width, height and depth of the internalformat specified. The size for a single slice of ETC/EAC is given in Table 1 below.

If a non-zero named buffer object is bound to the GL_PIXEL_UNPACK_BUFFER target (see glBindBuffer) while a texture image is specified, data is treated as a byte offset into the buffer object's data store.

Table 1. Compressed Internal Formats

Compressed Internal Format	Base Internal Format	Image Size
`GL_COMPRESSED_R11_EAC`	`GL_RED`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_SIGNED_R11_EAC`	`GL_RED`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_RG11_EAC`	`GL_RG`	`ceil(width/4) * ceil(height/4) * 16`
`GL_COMPRESSED_SIGNED_RG11_EAC`	`GL_RG`	`ceil(width/4) * ceil(height/4) * 16`
`GL_COMPRESSED_RGB8_ETC2`	`GL_RGB`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_SRGB8_ETC2`	`GL_RGB`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2`	`GL_RGBA`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2`	`GL_RGBA`	`ceil(width/4) * ceil(height/4) * 8`
`GL_COMPRESSED_RGBA8_ETC2_EAC`	`GL_RGBA`	`ceil(width/4) * ceil(height/4) * 16`
`GL_COMPRESSED_SRGBA8_ETC2_EAC`	`GL_RGBA`	`ceil(width/4) * ceil(height/4) * 16`

Errors

GL_INVALID_ENUM is generated if internalformat is not one of the specific compressed internal formats: GL_COMPRESSED_R11_EAC, GL_COMPRESSED_SIGNED_R11_EAC, GL_COMPRESSED_RG11_EAC, GL_COMPRESSED_SIGNED_RG11_EAC, GL_COMPRESSED_RGB8_ETC2, GL_COMPRESSED_SRGB8_ETC2, GL_COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2, GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2, GL_COMPRESSED_RGBA8_ETC2_EAC, or GL_COMPRESSED_SRGBA8_ETC2_EAC.

GL_INVALID_VALUE is generated if imageSize is not consistent with the format, dimensions, and contents of the specified compressed image data.

GL_INVALID_VALUE is generated if border is not 0.

GL_INVALID_OPERATION is generated if parameter combinations are not supported by the specific compressed internal format as specified in the specific texture compression extension. The ETC2/EAC texture compression algorithm supports only two-dimensional images. If internalformat is an ETC2/EAC format, glCompressedTexImage3D will generate an INVALID_OPERATION error if target is not TEXTURE_2D_ARRAY.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the buffer object's data store is currently mapped.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to the GL_PIXEL_UNPACK_BUFFER target and the data would be unpacked from the buffer object such that the memory reads required would exceed the data store size.

Undefined results, including abnormal program termination, are generated if data is not encoded in a manner consistent with the extension specification defining the internal compression format.

Associated Gets

glGet with argument GL_PIXEL_UNPACK_BUFFER_BINDING