glCompressedTexImage2D
- specify a two-dimensional compressed texture image
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
.
level
Specifies the level-of-detail number. Must be less than or equal to 0. Level 0 indicates a single mip-level. Negative values indicate how many mip-levels are described by data
.
internalformat
Specifies the color components in the texture. The following symbolic constants are accepted: GL_PALETTE4_RGB8_OES
, GL_PALETTE4_RGBA8_OES
, GL_PALETTE4_R5_G6_B5_OES
, GL_PALETTE4_RGBA4_OES
, GL_PALETTE4_RGB5_A1_OES
, GL_PALETTE8_RGB8_OES
, GL_PALETTE8_RGBA8_OES
, GL_PALETTE8_R5_G6_B5_OES
, GL_PALETTE8_RGBA4_OES
, and GL_PALETTE8_RGB5_A1_OES
.
width
Specifies the width of the texture image. Must be 2n + 2border for some integer n. All implementations support texture images that are at least 64 texels wide.
height
Specifies the height of the texture image. Must be 2m + 2border for some integer m. All implementations support texture images that are at least 64 texels high.
border
Specifies the width of the border. Must be 0.
imageSize
Specifies the size of the compressed image data in bytes.
data
Specifies a pointer to the compressed image data in memory.
glCompressedTexImage2D
defines a two-dimensional texture image in compressed format.
The supported compressed formats are paletted textures. The layout of the compressed image is a palette followed by multiple mip-levels of texture indices used for lookup into the palette. The palette format can be one of R5_G6_B5
, RGBA4
, RGB5_A1
, RGB8
, or RGBA8
. The texture indices can have a resolution of 4 or 8 bits. As a result, the number of palette entries is either 16 or 256. If level
is 0, only one mip-level of texture indices is described in data
. Otherwise, the negative value of level
specifies up to which mip-level the texture indices are described. A possibly remaining pad nibble for the lowest resolution mip-level is ignored.
glPixelStore
has no effect on compressed texture images.
glCompressedTexImage2D
specifies the two-dimensional texture for the currently bound texture, specified with glBindTexture
, and the current texture unit, specified with glActiveTexture
.
GL_INVALID_ENUM
is generated if target
is not GL_TEXTURE_2D
.
GL_INVALID_VALUE
may be generated if if level
is greater than 0 or the absolute value of level
is greater than log2max, where max
is the returned value of GL_MAX_TEXTURE_SIZE
.
GL_INVALID_ENUM
is generated if internalformat
is not one of the accepted symbolic constants.
GL_INVALID_VALUE
is generated if width
or height
is less than 0 or greater than 2 + GL_MAX_TEXTURE_SIZE
, or if either cannot be represented as 2k + 2border for some integer k.
GL_INVALID_VALUE
is generated if border
is not 0.
GL_INVALID_VALUE
is generated if imageSize
is not consistent with format, dimentions, and contents of the compressed image.
Copyright © 2003-2004 Silicon Graphics, Inc.
This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.
glActiveTexture
, glBindTexture
, glCompressedTexSubImage2D
, glCopyTexImage2D
, glCopyTexSubImage2D
, glPixelStore
, glTexEnv
, glTexImage2D
, glTexParameter