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 fol-
                lowing 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_BGR,      GL_BGRA,      GL_LUMINANCE,      and
                GL_LUMINANCE_ALPHA.

       wIn, hIn Specify in pixels the width and  height,  respec-
                tively, of the source image.

       typeIn   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,     GL_FLOAT,     GL_UNSIGNED_BYTE_3_3_2,
                GL_UNSIGNED_BYTE_2_3_3_REV,
                GL_UNSIGNED_SHORT_5_6_5,
                GL_UNSIGNED_SHORT_5_6_5_REV,
                GL_UNSIGNED_SHORT_4_4_4_4,
                GL_UNSIGNED_SHORT_4_4_4_4_REV,
                GL_UNSIGNED_SHORT_5_5_5_1,
                GL_UNSIGNED_SHORT_1_5_5_5_REV,
                GL_UNSIGNED_INT_8_8_8_8,
                GL_UNSIGNED_INT_8_8_8_8_REV,
                GL_UNSIGNED_INT_10_10_10_2,                   and
                GL_UNSIGNED_INT_2_10_10_10_REV.

       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    GL_UNSIGNED_BYTE,    GL_BYTE,    GL_BITMAP,
                GL_UNSIGNED_SHORT,   GL_SHORT,   GL_UNSIGNED_INT,
                GL_INT,     GL_FLOAT,     GL_UNSIGNED_BYTE_3_3_2,


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.

       When shrinking an image, gluScaleImage uses a  box  filter
       to  sample the source image and create pixels for the des-
       tination 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.


NOTES

       Formats     GL_BGR,     and     GL_BGRA,     and     types
       GL_UNSIGNED_BYTE_3_3_2,        GL_UNSIGNED_BYTE_2_3_3_REV,
       GL_UNSIGNED_SHORT_5_6_5,      GL_UNSIGNED_SHORT_5_6_5_REV,
       GL_UNSIGNED_SHORT_4_4_4_4,  GL_UNSIGNED_SHORT_4_4_4_4_REV,
       GL_UNSIGNED_SHORT_5_5_5_1,  GL_UNSIGNED_SHORT_1_5_5_5_REV,
       GL_UNSIGNED_INT_8_8_8_8,      GL_UNSIGNED_INT_8_8_8_8_REV,
       GL_UNSIGNED_INT_10_10_10_2,                            and
       GL_UNSIGNED_INT_2_10_10_10_REV are only available  if  the
       GL version is 1.2 or greater.


ERRORS

       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
       GL_UNSIGNED_BYTE_3_3_2 or  GL_UNSIGNED_BYTE_2_3_3_REV  and
       format is not GL_RGB.

       GLU_INVALID_OPERATION  is returned if typeIn or typeOut is
       GL_UNSIGNED_SHORT_5_6_5 or GL_UNSIGNED_SHORT_5_6_5_REV and
       format is not GL_RGB.

       GLU_INVALID_OPERATION  is returned if typeIn or typeOut is
       GL_UNSIGNED_SHORT_4_4_4_4 or GL_UNSIGNED_SHORT_4_4_4_4_REV
       and format is neither GL_RGBA nor GL_BGRA.

       GLU_INVALID_OPERATION  is returned if typeIn or typeOut is
       GL_UNSIGNED_SHORT_5_5_5_1 or GL_UNSIGNED_SHORT_1_5_5_5_REV
       and format is neither GL_RGBA nor GL_BGRA.



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