C SPECIFICATION

       void GLAPIENTRY glGetSeparableFilter( GLenum target,
                                             GLenum forma )

PARAMETERS

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

       forma   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.

       _param3 Data type of components in the output  images.   Symbolic  con-
               stants 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.

       _param4 Pointer to storage for the row filter image.

       _param5 Pointer to storage for the column filter image.

       _param6 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 _param4 and the column image is placed in _param5  accord-
       ing to the specifications in forma and _param3.  (In the current imple-
       mentation, _param6 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 forma  but  not  included  in  the
       internal  format  of the filters are returned as zero.  The assignments
       of internal color components to the components of forma are as follows:



                      -----------------------------------------
                      Internal Component   Resulting Component
                      -----------------------------------------
                      Red                  Red
                      Green                Green
                      Blue                 Blue

       GL_INVALID_ENUM  is generated if forma is not one of the allowable val-
       ues.

       GL_INVALID_ENUM is generated if _param3 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   _param3   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 forma is
       not GL_RGB.

       GL_INVALID_OPERATION   is   generated   if   _param3    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 forma
       is neither GL_RGBA nor GL_BGRA.

ASSOCIATED GETS

       glGetConvolutionParameter

SEE ALSO

       glGetConvolutionFilter, glConvolutionParameter, glSeparableFilter2D



                                                      GLGETSEPARABLEFILTER(3G)