glGetConvolutionParameterEXT(3G)

NAME
     glGetConvolutionParameterfvEXT, glGetConvolutionParameterivEXT - get
     convolution parameters


C SPECIFICATION
     void glGetConvolutionParameterfvEXT( GLenum target,
                                          GLenum pname,
                                          GLfloat *params )
     void glGetConvolutionParameterivEXT( GLenum target,
                                          GLenum pname,
                                          GLint *params )


PARAMETERS
     target  The filter whose parameters are to be retrieved.  Must be one of
             GL_CONVOLUTION_1D_EXT, GL_CONVOLUTION_2D_EXT, or
             GL_SEPARABLE_2D_EXT.

     pname   The parameter to be retrieved.  Must be one of
             GL_CONVOLUTION_BORDER_MODE_EXT, GL_CONVOLUTION_FILTER_SCALE_EXT,
             GL_CONVOLUTION_FILTER_BIAS_EXT, GL_CONVOLUTION_FORMAT_EXT,
             GL_CONVOLUTION_WIDTH_EXT, GL_CONVOLUTION_HEIGHT_EXT,
             GL_MAX_CONVOLUTION_WIDTH_EXT, or GL_MAX_CONVOLUTION_HEIGHT_EXT.

     params  Pointer to storage for the parameters to be retrieved.

DESCRIPTION
     glGetConvolutionParameterEXT retrieves convolution parameters.  target
     determines which convolution filter is queried.  pname determines which
     parameter is returned:

     GL_CONVOLUTION_BORDER_MODE_EXT
          The convolution border mode.  See glConvolutionParameterEXT for a
          list of border modes.

     GL_CONVOLUTION_FILTER_SCALE_EXT
          The current filter scale factors.  params must be a pointer to an
          array of four elements, which will receive the red, green, blue, and
          alpha filter scale factors in that order.

     GL_CONVOLUTION_FILTER_BIAS_EXT
          The current filter bias factors.  params must be a pointer to an
          array of four elements, which will receive the red, green, blue, and
          alpha filter bias terms in that order.

     GL_CONVOLUTION_FORMAT_EXT
          The current internal format.  See glConvolutionFilter1DEXT,
          glConvolutionFilter2DEXT, and glSeparableFilter2DEXT for lists of
          allowable formats.
     GL_CONVOLUTION_WIDTH_EXT
          The current filter image width.

     GL_CONVOLUTION_HEIGHT_EXT
          The current filter image height.

     GL_MAX_CONVOLUTION_WIDTH_EXT
          The maximum acceptable filter image width.

     GL_MAX_CONVOLUTION_HEIGHT_EXT
          The maximum acceptable filter image height.

ERRORS
     GL_INVALID_ENUM is generated if target is not one of the allowable
     values.

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

     GL_INVALID_ENUM is generated if target is GL_CONVOLUTION_1D_EXT and pname
     is GL_CONVOLUTION_HEIGHT_EXT or GL_MAX_CONVOLUTION_HEIGHT_EXT.

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


MACHINE DEPENDENCIES
     RealityEngine, RealityEngine2, and VTX systems cannot retrieve
     GL_MAX_CONVOLUTION_WIDTH_EXT or GL_MAX_CONVOLUTION_HEIGHT_EXT.


SEE ALSO
     glGetConvolutionFilterEXT, glGetSeparableFilter2DEXT,
     glConvolutionParameterEXT.