GLGETSEPARABLEFILTER(3G)												  GLGETSEPARABLEFILTER(3G)

NAME

       glGetSeparableFilter - get separable convolution filter kernel images

C SPECIFICATION

       void glGetSeparableFilter( GLenum target,
				  GLenum format,
				  GLenum type,
				  GLvoid *row,
				  GLvoid *column,
				  GLvoid *span )

PARAMETERS

       target  The separable filter to be retrieved.  Must be GL_SEPARABLE_2D.

       format  Format of the output images.  Must be one of GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_RGB, GL_BGR GL_RGBA, GL_BGRA, GL_LUMINANCE, or
	       GL_LUMINANCE_ALPHA.

       type    Data type of components in  the	output	images.   Symbolic  constants  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 are accepted.

       row     Pointer to storage for the row filter image.

       column  Pointer to storage for the column filter image.

       span    Pointer to storage for the span filter image (currently unused).

DESCRIPTION

       glGetSeparableFilter returns the two one-dimensional filter kernel images for the current separable 2D convolution filter.  The	row  image
       is  placed in row and the column image is placed in column according to the specifications in format and type.  (In the current implementa-
       tion, span is not affected in any way.)	No pixel transfer operations are performed on the images, but the relevant pixel storage modes are
       applied.

       Color  components  that	are  present  in format but not included in the internal  of the filters are returned as zero.	The assignments of
       internal color components to the components of format are as follows:

	Internal Component     Resulting Component
	Red		       Red
	Green		       Green
	Blue		       Blue
	Alpha		       Alpha
	Luminance	       Red
	Intensity	       Red

NOTES

       glGetSeparableFilter is present only if GL_ARB_imaging is returned when glGetString is called with an argument of GL_EXTENSIONS.

       Non-separable 2D filters must be retrieved with glGetConvolutionFilter.

ERRORS

       GL_INVALID_ENUM is generated if target is not GL_SEPARABLE_2D.

       GL_INVALID_ENUM is generated if format is not one of the allowable values.

       GL_INVALID_ENUM is generated if type is not one of the allowable values.

       GL_INVALID_OPERATION is generated if glGetSeparableFilter is executed between the execution of glBegin and the corresponding  execution	of
       glEnd.

       GL_INVALID_OPERATION  is  generated  if	type  is  one  of  GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV, GL_UNSIGNED_SHORT_5_6_5, or
       GL_UNSIGNED_SHORT_5_6_5_REV and format is not GL_RGB.

       GL_INVALID_OPERATION is generated if type is one of  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 and format is neither GL_RGBA nor GL_BGRA.

ASSOCIATED GETS

       glGetConvolutionParameter

SEE ALSO

       glGetConvolutionFilter, glConvolutionParameter, glSeparableFilter2D

															  GLGETSEPARABLEFILTER(3G)