glTexSubImage1DEXT(3G) OpenGL Reference glTexSubImage1DEXT(3G)
NAME
glTexSubImage1DEXT - specify a one-dimensional texture subimage
C SPECIFICATION
void glTexSubImage1DEXT( GLenum target,
GLint level,
GLint xoffset,
GLsizei width,
GLenum format,
GLenum type,
const GLvoid *pixels )
PARAMETERS
target Specifies the target texture. Must be GLTEXTURE1D.
level Specifies the level-of-detail number. Level 0 is the base image
level. Level n is the nth mipmap reduction image.
xoffset Specifies a texel offset in the x direction within the texture
array.
width Specifies the width of the texture subimage.
format Specifies the format of the pixel data. The following symbolic
values are accepted: GLCOLORINDEX, GLRED, GLGREEN, GLBLUE,
GLALPHA, GLRGB, GLRGBA, GLABGREXT, GLLUMINANCE, and
GLLUMINANCEALPHA.
type Specifies the data type of the pixel data. The following
symbolic values are accepted: GLUNSIGNEDBYTE, GLBYTE,
GLBITMAP, GLUNSIGNEDSHORT, GLSHORT, GLUNSIGNEDINT, GLINT,
GLFLOAT, GLUNSIGNEDBYTE332EXT,
GLUNSIGNEDSHORT4444EXT, GLUNSIGNEDSHORT5551EXT,
GLUNSIGNEDINT8888EXT, and GLUNSIGNEDINT1010102EXT.
pixels Specifies a pointer to the image data in memory.
DESCRIPTION
Texturing maps a portion of a specified texture image onto each graphical
primitive for which texturing is enabled. One-dimensional texturing is
enabled and disabled using glEnable and glDisable with argument
GLTEXTURE1D.
glTexSubImage1DEXT redefines a contiguous subregion of an existing one-
dimensional texture array. The texels referenced by pixels replace the
portion of the existing texture array with x indices xoffset and
xoffset+width-1, inclusive. This region may not include any texels
outside the range of the texture array as it was originally specified.
It is not an error to specify a subtexture with zero width, but such a
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glTexSubImage1DEXT(3G) OpenGL Reference glTexSubImage1DEXT(3G)
specification has no effect.
NOTES
Texturing has no effect in color index mode.
glPixelStore and glPixelTransfer modes affect texture images in exactly
the way they affect glDrawPixels.
glTexSubImage1DEXT is part of the EXTsubtexture extension.
If type is set to GLUNSIGNEDBYTE332EXT,
GLUNSIGNEDSHORT4444EXT, GLUNSIGNEDSHORT5551EXT,
GLUNSIGNEDINT8888EXT, or GLUNSIGNEDINT1010102EXT and the
EXTpackedpixels extension is not supported then a GLINVALIDENUM error
is generated.
See glIntro for more information on using extensions.
ERRORS
GLINVALIDENUM is generated when target is not GLTEXTURE1D.
GLINVALIDOPERATION is generated when the texture image has not been
defined by a previous glTexImage1D operation.
GLINVALIDVALUE is generated if level is less than zero or greater than
log (max), where max is the returned value of GLMAXTEXTURESIZE.
2
GLINVALIDVALUE is generated if xoffset<-TEXTURE_BORDER, or if
(xoffset+width)>(TEXTURE_WIDTH-TEXTURE_BORDER), where TEXTURE_WIDTH is
the width of the image being modified and TEXTURE_BORDER is the border
width of the image being modified. Note that TEXTURE_WIDTH includes
twice the border width.
GLINVALIDENUM is generated when format is not an accepted format
constant. Format constants other than GLSTENCILINDEX and
GLDEPTHCOMPONENT are accepted.
GLINVALIDENUM is generated when type is not a type constant.
GLINVALIDENUM is generated if type is GLBITMAP and format is not
GLCOLORINDEX.
GLINVALIDOPERATION is generated if glTexSubImage1DEXT is executed
between the execution of glBegin and the corresponding execution of
glEnd.
ASSOCIATED GETS
glGetTexImage
glIsEnabled with argument GLTEXTURE1D
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glTexSubImage1DEXT(3G) OpenGL Reference glTexSubImage1DEXT(3G)
MACHINE DEPENDENCIES
On InfiniteReality systems, there is a performance benefit when the width
of the image to be transferred to texture memory is a multiple of 8.
Texture borders are not supported on InfiniteReality systems.
Applications should use borderless textures and GLCLAMPTOEDGESGIS
wrap mode.
The EXTpackedpixels extension is not supported on RealityEngine,
RealityEngine2, and VTX systems.
glTexSubImage1D and glTexSubImage1DEXT are not supported on
RealityEngine, RealityEngine2, and VTX systems.
On High Impact and Maximum Impact systems, if the right side of the image
to be transferred to texture memory is not the right side of the texture,
then its index must be a multiple of 32, where index = xoffset+width.
Otherwise it will generate a GLINVALIDVALUE error.
SEE ALSO
glDrawPixels, glFog, glPixelStore, glPixelTransfer, glTexEnv, glTexGen,
glTexImage1D, glTexParameter.
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