gluScaleImage

GLUSCALEIMAGE(3G)					    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	 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_BGR,   GL_BGRA,	  GL_LUMINANCE,	  and
		GL_LUMINANCE_ALPHA.

       wIn, hIn Specify	 in pixels the width and height, respectively, 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,		  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,				   or
		GL_UNSIGNED_INT_2_10_10_10_REV.

       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 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 magni-
       fying an image, the pixels from the source image are linearly interpo-
       lated 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 accept-
       able 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.

       GLU_INVALID_OPERATION   is   returned   if   typeIn   or	  typeOut  is
       GL_UNSIGNED_INT_8_8_8_8 or GL_UNSIGNED_INT_8_8_8_8_REV and  format  is
       neither GL_RGBA nor GL_BGRA.

       GLU_INVALID_OPERATION   is   returned   if   typeIn   or	  typeOut  is
       GL_UNSIGNED_INT_10_10_10_2 or GL_UNSIGNED_INT_2_10_10_10_REV and	 for-
       mat is neither GL_RGBA nor GL_BGRA.

SEE ALSO
       glDrawPixels(3G),       glReadPixels(3G),       gluBuild1DMipmaps(3G),
       gluBuild2DMipmaps(3G), gluBuild3DMipmaps(3G),  gluErrorString(3G)




							    GLUSCALEIMAGE(3G)