gluScaleImage()gluScaleImage()NAMEgluScaleImage - scale an image to an arbitrary size
SYNOPSIS
GLint gluScaleImage(
GLenum format,
GLsizei wIn,
GLsizei hIn,
GLenum typeIn,
const void *dataIn,
GLsizei wOut,
GLsizei hOut,
GLenum typeOut,
GLvoid* dataOut );
PARAMETERS
Specifies the format of the pixel data. The following symbolic values
are valid: GL_COLOR_INDEX, GL_STENCIL_INDEX, GL_DEPTH_COMPONENT,
GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_RGB, GL_RGBA, GL_LUMINANCE, and
GL_LUMINANCE_ALPHA. Specify the width and height, respectively, of the
source image that is scaled. Specifies the data type for dataIn. Must
be one of GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT,
GL_SHORT, GL_UNSIGNED_INT, GL_INT, or GL_FLOAT. Specifies a pointer to
the source image. Specify the width and height, respectively, of the
destination image. Specifies the data type for dataOut. Must be one of
GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT, GL_SHORT,
GL_UNSIGNED_INT, GL_INT, or GL_FLOAT. Specifies a pointer to the des‐
tination image.
DESCRIPTIONgluScaleImage() scales a pixel image using the appropriate pixel store
modes to unpack data from the source image and pack data into the des‐
tination image.
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 0 indicates success, otherwise a GLU error code is
returned (see gluErrorString()).
See the glReadPixels() reference page for a description of the accept‐
able values for format, typeIn, and typeOut.
ERRORS
GLU_INVALID_VALUE is returned if wIn, hIn, wOut, or hOut are < 0.
GLU_INVALID_ENUM is returned if format, typeIn, or typeOut are not
legal.
SEE ALSOglReadPixels(3), glDrawPixels(3), gluBuild1DMipmaps(3),
gluBuild2DMipmaps(3), gluErrorString(3)gluScaleImage()