glgetconvolutionparameterext()



glGetConvolutionParameterEXT(3G)                              OpenGL Reference



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
             GLCONVOLUTION1DEXT, GLCONVOLUTION2DEXT, or
             GLSEPARABLE2DEXT.

     pname   The parameter to be retrieved.  Must be one of
             GLCONVOLUTIONBORDERMODEEXT, GLCONVOLUTIONFILTERSCALEEXT,
             GLCONVOLUTIONFILTERBIASEXT, GLCONVOLUTIONFORMATEXT,
             GLCONVOLUTIONWIDTHEXT, GLCONVOLUTIONHEIGHTEXT,
             GLMAXCONVOLUTIONWIDTHEXT, or GLMAXCONVOLUTIONHEIGHTEXT.

     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:

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

     GLCONVOLUTIONFILTERSCALEEXT
          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.

     GLCONVOLUTIONFILTERBIASEXT
          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.

     GLCONVOLUTIONFORMATEXT
          The current internal format.  See glConvolutionFilter1DEXT,
          glConvolutionFilter2DEXT, and glSeparableFilter2DEXT for lists of
          allowable formats.





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glGetConvolutionParameterEXT(3G)                              OpenGL Reference



     GLCONVOLUTIONWIDTHEXT
          The current filter image width.

     GLCONVOLUTIONHEIGHTEXT
          The current filter image height.

     GLMAXCONVOLUTIONWIDTHEXT
          The maximum acceptable filter image width.

     GLMAXCONVOLUTIONHEIGHTEXT
          The maximum acceptable filter image height.

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

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

     GLINVALIDENUM is generated if target is GLCONVOLUTION1DEXT and pname
     is GLCONVOLUTIONHEIGHTEXT or GLMAXCONVOLUTIONHEIGHTEXT.

     GLINVALIDOPERATION 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
     GLMAXCONVOLUTIONWIDTHEXT or GLMAXCONVOLUTIONHEIGHTEXT.


SEE ALSO
     glGetConvolutionFilterEXT, glGetSeparableFilter2DEXT,
     glConvolutionParameterEXT.





















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