scale an image to an arbitrary size
GLint gluScaleImage( | GLenum | format, |
| GLsizei | wIn, | |
| GLsizei | hIn, | |
| GLenum | typeIn, | |
| const void * | dataIn, | |
| GLsizei | wOut, | |
| GLsizei | hOut, | |
| GLenum | typeOut, | |
| GLvoid* | dataOut); |
format
Specifies the format of the pixel data.
The following symbolic values are valid:
GLU_COLOR_INDEX,
GLU_STENCIL_INDEX,
GLU_DEPTH_COMPONENT,
GLU_RED,
GLU_GREEN,
GLU_BLUE,
GLU_ALPHA,
GLU_RGB,
GLU_RGBA,
GLU_BGR,
GLU_BGRA,
GLU_LUMINANCE, and
GLU_LUMINANCE_ALPHA.
wIn, hInSpecify in pixels the width and height, respectively, of the source image.
typeIn
Specifies the data type for dataIn. Must be one of
GLU_UNSIGNED_BYTE,
GLU_BYTE,
GLU_BITMAP,
GLU_UNSIGNED_SHORT,
GLU_SHORT,
GLU_UNSIGNED_INT,
GLU_INT,
GLU_FLOAT,
GLU_UNSIGNED_BYTE_3_3_2,
GLU_UNSIGNED_BYTE_2_3_3_REV,
GLU_UNSIGNED_SHORT_5_6_5,
GLU_UNSIGNED_SHORT_5_6_5_REV,
GLU_UNSIGNED_SHORT_4_4_4_4,
GLU_UNSIGNED_SHORT_4_4_4_4_REV,
GLU_UNSIGNED_SHORT_5_5_5_1,
GLU_UNSIGNED_SHORT_1_5_5_5_REV,
GLU_UNSIGNED_INT_8_8_8_8,
GLU_UNSIGNED_INT_8_8_8_8_REV,
GLU_UNSIGNED_INT_10_10_10_2, or
GLU_UNSIGNED_INT_2_10_10_10_REV.
dataInSpecifies a pointer to the source image.
wOut, hOutSpecify the width and height, respectively, in pixels of the destination image.
typeOut
Specifies the data type for dataOut. Must be one of
GLU_UNSIGNED_BYTE,
GLU_BYTE,
GLU_BITMAP,
GLU_UNSIGNED_SHORT,
GLU_SHORT,
GLU_UNSIGNED_INT,
GLU_INT,
GLU_FLOAT,
GLU_UNSIGNED_BYTE_3_3_2,
GLU_UNSIGNED_BYTE_2_3_3_REV,
GLU_UNSIGNED_SHORT_5_6_5,
GLU_UNSIGNED_SHORT_5_6_5_REV,
GLU_UNSIGNED_SHORT_4_4_4_4,
GLU_UNSIGNED_SHORT_4_4_4_4_REV,
GLU_UNSIGNED_SHORT_5_5_5_1,
GLU_UNSIGNED_SHORT_1_5_5_5_REV,
GLU_UNSIGNED_INT_8_8_8_8,
GLU_UNSIGNED_INT_8_8_8_8_REV,
GLU_UNSIGNED_INT_10_10_10_2, or
GLU_UNSIGNED_INT_2_10_10_10_REV.
dataOutSpecifies a pointer to the destination image.
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.
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.
Formats GLU_BGR, and GLU_BGRA, and types
GLU_UNSIGNED_BYTE_3_3_2,
GLU_UNSIGNED_BYTE_2_3_3_REV,
GLU_UNSIGNED_SHORT_5_6_5,
GLU_UNSIGNED_SHORT_5_6_5_REV,
GLU_UNSIGNED_SHORT_4_4_4_4,
GLU_UNSIGNED_SHORT_4_4_4_4_REV,
GLU_UNSIGNED_SHORT_5_5_5_1,
GLU_UNSIGNED_SHORT_1_5_5_5_REV,
GLU_UNSIGNED_INT_8_8_8_8,
GLU_UNSIGNED_INT_8_8_8_8_REV,
GLU_UNSIGNED_INT_10_10_10_2, and
GLU_UNSIGNED_INT_2_10_10_10_REV are only available if the GL version
is 1.2 or greater.
GLU_INVALID_VALUE is returned if wIn, hIn, wOut, or hOut
is negative.
GLU_INVALID_ENUM is returned if format, typeIn, or typeOut is not
legal.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_BYTE_3_3_2 or GLU_UNSIGNED_BYTE_2_3_3_REV
and format is not GLU_RGB.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_SHORT_5_6_5 or GLU_UNSIGNED_SHORT_5_6_5_REV
and format is not GLU_RGB.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_SHORT_4_4_4_4 or GLU_UNSIGNED_SHORT_4_4_4_4_REV
and format is neither GLU_RGBA nor GLU_BGRA.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_SHORT_5_5_5_1 or GLU_UNSIGNED_SHORT_1_5_5_5_REV
and format is neither GLU_RGBA nor GLU_BGRA.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_INT_8_8_8_8 or GLU_UNSIGNED_INT_8_8_8_8_REV
and format is neither GLU_RGBA nor GLU_BGRA.
GLU_INVALID_OPERATION is returned if typeIn or typeOut is
GLU_UNSIGNED_INT_10_10_10_2 or GLU_UNSIGNED_INT_2_10_10_10_REV
and format is neither GLU_RGBA nor GLU_BGRA.
gluBuild1DMipmaps, gluBuild2DMipmaps, gluBuild3DMipmaps, gluErrorString, glDrawPixels, glReadPixels
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/.