glCompressedTexImage2D — specify a two-dimensional texture image in a compressed format
void glCompressedTexImage2D( | GLenum | target, |
| GLint | level, | |
| GLenum | internalformat, | |
| GLsizei | width, | |
| GLsizei | height, | |
| GLint | border, | |
| GLsizei | imageSize, | |
| const GLvoid * | data); |
target
Specifies the target texture.
Must be GL_TEXTURE_2D, GL_PROXY_TEXTURE_2D,
GL_TEXTURE_CUBE_MAP_POSITIVE_X,
GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
GL_TEXTURE_CUBE_MAP_NEGATIVE_Y,
GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or
GL_PROXY_TEXTURE_CUBE_MAP.
levelSpecifies 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 including the border if any. If the GL version does not support non-power-of-two sizes, this value must be
height
Specifies the height of the texture image including the border if any. If the GL version does not support non-power-of-two sizes, this value must be
Must be
borderSpecifies the width of the border. Must be either 0 or 1.
imageSize
Specifies the number of unsigned bytes of image data starting at the
address specified by data.
dataSpecifies a pointer to the compressed image data in memory.
Texturing maps a portion of a specified texture image onto each graphical
primitive for which texturing is enabled. To enable and disable
two-dimensional texturing, call glEnable and glDisable with argument
GL_TEXTURE_2D. To enable and disable texturing using
cube-mapped textures, call glEnable and glDisable with argument
GL_TEXTURE_CUBE_MAP.
glCompressedTexImage2D loads a previously defined, and retrieved, compressed two-dimensional
texture image if target is GL_TEXTURE_2D (see glTexImage2D).
If target is GL_PROXY_TEXTURE_2D, no data is read from data, but
all of the texture image state is recalculated, checked for consistency,
and checked against the implementation's capabilities. If the
implementation cannot handle a texture of the requested texture size, it
sets all of the image state to 0, but does not generate an error (see
glGetError). To query for an entire mipmap array, use an image array level
greater than or equal to 1.
internalformat must be an extension-specified compressed-texture format.
When a texture is loaded with glTexImage2D using a generic compressed
texture format (e.g., GL_COMPRESSED_RGB), the GL selects from one of
its extensions supporting compressed textures. In order to load the
compressed texture image using glCompressedTexImage2D, query the compressed texture image's
size and format using glGetTexLevelParameter.
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.
glCompressedTexImage2D is available only if the GL version is 1.3 or greater.
Non-power-of-two textures are supported if the GL version is 2.0 or greater, or if the implementation exports the GL_ARB_texture_non_power_of_two extension.
GL_INVALID_ENUM is generated if internalformat is one of the generic compressed internal formats: GL_COMPRESSED_ALPHA,
GL_COMPRESSED_LUMINANCE, GL_COMPRESSED_LUMINANCE_ALPHA,
GL_COMPRESSED_INTENSITY, GL_COMPRESSED_RGB, or
GL_COMPRESSED_RGBA.
GL_INVALID_VALUE is generated if imageSize is not consistent with
the format, dimensions, and contents of the specified compressed image
data.
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.
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.
GL_INVALID_OPERATION is generated if glCompressedTexImage2D
is executed between the execution of glBegin
and the corresponding execution of glEnd.
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.
glGet with argument GL_TEXTURE_COMPRESSED
glGet with argument GL_PIXEL_UNPACK_BUFFER_BINDING
glGetTexLevelParameter with arguments GL_TEXTURE_INTERNAL_FORMAT
and GL_TEXTURE_COMPRESSED_IMAGE_SIZE
glIsEnabled with argument
GL_TEXTURE_2D or GL_TEXTURE_CUBE_MAP
glActiveTexture, glColorTable, glCompressedTexImage1D, glCompressedTexImage3D, glCompressedTexSubImage1D, glCompressedTexSubImage2D, glCompressedTexSubImage3D, glConvolutionFilter1D, glCopyPixels, glCopyTexImage1D, glCopyTexSubImage1D, glCopyTexSubImage2D, glCopyTexSubImage3D, glDrawPixels, glMatrixMode, glPixelStore, glPixelTransfer, glTexEnv, glTexGen, glTexImage2D, glTexImage3D, glTexSubImage1D, glTexSubImage2D, glTexSubImage3D, glTexParameter
Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.