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  im‐
       ages  for the current separable 2D convolution filter.  The row image is
       placed in _param4 and the column image is placed in _param5 according to
       the  specifications  in  forma and _param3.  (In the current implementa‐
       tion, _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  in‐
       ternal  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
                       Alpha                Alpha
                       Luminance            Red
                       Intensity            Red
                       ─────────────────────────────────────────

NOTES
       glGetSeparableFilter is present only if GL_ARB_imaging is returned  when
       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)