void GLAPIENTRY glConvolutionParameterf( GLenum target,
                                                GLenum pnam )
       void GLAPIENTRY glConvolutionParameteri( GLenum target,
                                                GLenum pnam )

PARAMETERS
       target  The target for  the  convolution  parameter.   Must  be  one  of
               GL_CONVOLUTION_1D, GL_CONVOLUTION_2D, or GL_SEPARABLE_2D.

       pnam    The parameter to be set.  Must be GL_CONVOLUTION_BORDER_MODE.

       _param3(1)
               The    parameter    value.     Must   be   one   of   GL_REDUCE,
               GL_CONSTANT_BORDER, GL_REPLICATE_BORDER.

C SPECIFICATION
       void GLAPIENTRY glConvolutionParameterfv( GLenum target,
                                                 GLenum pnam )
       void GLAPIENTRY glConvolutionParameteriv( GLenum target,
                                                 GLenum pnam )

PARAMETERS
       target The target  for  the  convolution  parameter.   Must  be  one  of
              GL_CONVOLUTION_1D, GL_CONVOLUTION_2D, or GL_SEPARABLE_2D.

       pnam   The     parameter    to    be    set.     Must    be    one    of
              GL_CONVOLUTION_BORDER_MODE,          GL_CONVOLUTION_BORDER_COLOR,
              GL_CONVOLUTION_FILTER_SCALE, or GL_CONVOLUTION_FILTER_BIAS.

       _param3(2)
              The  parameter  value.   If  pnam  is GL_CONVOLUTION_BORDER_MODE,
              _param3(2) must  be  one  of  GL_REDUCE,  GL_CONSTANT_BORDER,  or
              GL_REPLICATE_BORDER.   Otherwise, must be a vector of four values
              (for red, green, blue, and alpha, respectively) to  be  used  for
              scaling  (when  pnam  is GL_CONVOLUTION_FILTER_SCALE), or biasing
              (when pnam is GL_CONVOLUTION_FILTER_BIAS)  a  convolution  filter
              kernel  or  setting  the  constant  border  color  (when  pnam is
              GL_CONVOLUTION_BORDER_COLOR.

DESCRIPTION
       glConvolutionParameter sets the value of a convolution parameter.

       target selects the convolution filter to be affected: GL_CONVOLUTION_1D,
       GL_CONVOLUTION_2D,  or  GL_SEPARABLE_2D  for the 1D, 2D, or separable 2D
       filter, respectively.

       pnam selects the parameter to be  changed.   GL_CONVOLUTION_FILTER_SCALE
       and  GL_CONVOLUTION_FILTER_BIAS affect the definition of the convolution
       filter kernel;  see  glConvolutionFilter1D,  glConvolutionFilter2D,  and
       glSeparableFilter2D for details.  In these cases, _param3(2) is an array
       of four values to be applied to red, green, blue, and alpha values,  re‐
       spectively.  The initial value for GL_CONVOLUTION_FILTER_SCALE is (1, 1,
              are zero through Ws−Wf in width and zero through Hs−Hf in height.

       GL_CONSTANT_BORDER
              The  image  resulting  from  convolution  is the same size as the
              source image, and processed as if  the  source  image  were  sur‐
              rounded   by   pixels   with   their   color   specified  by  the
              GL_CONVOLUTION_BORDER_COLOR.

       GL_REPLICATE_BORDER
              The image resulting from convolution is  the  same  size  as  the
              source image, and processed as if the outermost pixel on the bor‐
              der of the source image were replicated.

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

       In cases where errors can result from the specification of invalid image
       dimensions, it is the dimensions after convolution that are tested,  not
       the  dimensions of the source image.  For example, glTexImage1D requires
       power-of-two image size.  When GL_REDUCE border mode is in  effect,  the
       source image must be larger than the final power-of-two size by one less
       than the size of the 1D filter kernel.

ERRORS
       GL_INVALID_ENUM is generated if target is not one of the allowable  val‐
       ues.

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

       GL_INVALID_ENUM  is  generated if pnam is GL_CONVOLUTION_BORDER_MODE and
       _param3(1)   is   not   one   of   GL_REDUCE,   GL_CONSTANT_BORDER,   or
       GL_REPLICATE_BORDER.

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

ASSOCIATED GETS
       glGetConvolutionParameter

SEE ALSO
       glConvolutionFilter1D,    glConvolutionFilter2D,    glSeparableFilter2D,
       glGetConvolutionParameter

                                                     GLCONVOLUTIONPARAMETER(3G)