gluScaleImage(3G) OpenGL Reference gluScaleImage(3G)
NAME
gluScaleImage - scale an image to an arbitrary size
C SPECIFICATION
GLint gluScaleImage( GLenum format,
GLsizei wIn,
GLsizei hIn,
GLenum typeIn,
const void *dataIn,
GLsizei wOut,
GLsizei hOut,
GLenum typeOut,
GLvoid* dataOut )
PARAMETERS
format Specifies the format of the pixel data. The following symbolic
values are valid: GLCOLORINDEX, GLSTENCILINDEX,
GLDEPTHCOMPONENT, GLRED, GLGREEN, GLBLUE, GLALPHA, GLRGB,
GLRGBA, GLLUMINANCE, GLLUMINANCEALPHA, and GLABGREXT.
wIn, hIn Specify the width and height, respectively, in pixels of the
source image.
typeIn Specifies the data type for dataIn. Must be one of
GLUNSIGNEDBYTE, GLBYTE, GLBITMAP, GLUNSIGNEDSHORT,
GLSHORT, GLUNSIGNEDINT, GLINT, GLFLOAT,
GLUNSIGNEDBYTE332EXT, GLUNSIGNEDSHORT4444EXT,
GLUNSIGNEDSHORT5551EXT, GLUNSIGNEDINT8888EXT, or
GLUNSIGNEDINT1010102EXT.
dataIn Specifies a pointer to the source image.
wOut, hOut
Specify the width and height, respectively, in pixels of the
destination image.
typeOut Specifies the data type for dataOut. Must be one of
GLUNSIGNEDBYTE, GLBYTE, GLBITMAP, GLUNSIGNEDSHORT,
GLSHORT, GLUNSIGNEDINT, GLINT, GLFLOAT,
GLUNSIGNEDBYTE332EXT, GLUNSIGNEDSHORT4444EXT,
GLUNSIGNEDSHORT5551EXT, GLUNSIGNEDINT8888EXT, or
GLUNSIGNEDINT1010102EXT.
dataOut Specifies a pointer to the destination image.
DESCRIPTION
gluScaleImage scales a pixel image using the appropriate pixel store
modes to unpack data from the source image and pack data into the
destination image.
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gluScaleImage(3G) OpenGL Reference gluScaleImage(3G)
When shrinking an image, gluScaleImage uses a box filter to sample the
source image and create pixels for the destination image. When
magnifying an image, the pixels from the source image are linearly
interpolated to create the destination image.
A return value of zero indicates success, otherwise a GLU error code is
returned (see gluErrorString).
See the glReadPixels reference page for a description of the acceptable
values for the format, typeIn, and typeOut parameters.
ERRORS
GLUINVALIDVALUE is returned if wIn, hIn, wOut or hOut is negative.
GLUINVALIDENUM is returned if format, typeIn or typeOut are not legal.
GLUINVALIDOPERATION is returned if typeIn or typeOut is
GLUNSIGNEDBYTE332EXT and format is not GLRGB.
GLUINVALIDOPERATION is returned if typeIn or typeOut is
GLUNSIGNEDSHORT4444EXT and format is neither GLRGBA nor
GLABGREXT.
GLUINVALIDOPERATION is returned if typeIn or typeOut is
GLUNSIGNEDSHORT5551EXT and format is neither GLRGBA nor
GLABGREXT.
GLUINVALIDOPERATION is returned if typeIn or typeOut is
GLUNSIGNEDINT8888EXT and format is neither GLRGBA nor
GLABGREXT.
GLUINVALIDOPERATION is returned if typeIn or typeOut is
GLUNSIGNEDINT1010102EXT and format is neither GLRGBA nor
GLABGREXT.
GLUINVALIDOPERATION is returned if format is GLABGREXT and the
GLEXTabgr extension is not supported.
GLUINVALIDOPERATION is returned if typeIn or typeOut is either
GLUNSIGNEDBYTE332EXT, GLUNSIGNEDSHORT4444EXT,
GLUNSIGNEDSHORT5551EXT, GLUNSIGNEDINT8888EXT or
GLUNSIGNEDINT1010102EXT and the GLEXTpackedpixels extension is
not supported.
SEE ALSO
glDrawPixels, glReadPixels, gluBuild1DMipmaps, gluBuild2DMipmaps,
gluErrorString
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