void GLAPIENTRY glCopyConvolutionFilter1D( GLenum targe )

PARAMETERS
       targe  Must be GL_CONVOLUTION_1D.

       _param2
              The internal format of the convolution filter kernel.  The allow‐
              able  values  are  GL_ALPHA,  GL_ALPHA4,  GL_ALPHA8,  GL_ALPHA12,
              GL_ALPHA16,    GL_LUMINANCE,    GL_LUMINANCE4,     GL_LUMINANCE8,
              GL_LUMINANCE12,        GL_LUMINANCE16,        GL_LUMINANCE_ALPHA,
              GL_LUMINANCE4_ALPHA4, GL_LUMINANCE6_ALPHA2, GL_LUMINANCE8_ALPHA8,
              GL_LUMINANCE12_ALPHA4,                    GL_LUMINANCE12_ALPHA12,
              GL_LUMINANCE16_ALPHA16,       GL_INTENSITY,        GL_INTENSITY4,
              GL_INTENSITY8,   GL_INTENSITY12,   GL_INTENSITY16,   GL_R3_G3_B2,
              GL_RGB, GL_RGB4, GL_RGB5, GL_RGB8, GL_RGB10, GL_RGB12,  GL_RGB16,
              GL_RGBA,  GL_RGBA2,  GL_RGBA4, GL_RGB5_A1, GL_RGBA8, GL_RGB10_A2,
              GL_RGBA12, or GL_RGBA16.

       _param3, _param4
              The window space coordinates of the lower-left coordinate of  the
              pixel array to copy.

       _param5
              The width of the pixel array to copy.

DESCRIPTION
       glCopyConvolutionFilter1D  defines  a one-dimensional convolution filter
       kernel with pixels from the current  GL_READ_BUFFER  (rather  than  from
       main memory, as is the case for glConvolutionFilter1D).

       The   screen-aligned   pixel   rectangle   with   lower-left  corner  at
       (_param3, _param4), width _param5 and height 1 is  used  to  define  the
       convolution  filter.   If  any pixels within this region are outside the
       window that is associated with the GL context, the values  obtained  for
       those pixels are undefined.

       The pixels in the rectangle are processed exactly as if glReadPixels had
       been called with format set to RGBA, but the process stops  just  before
       final  conversion.  The R, G, B, and A components of each pixel are next
       scaled by the four 1D GL_CONVOLUTION_FILTER_SCALE parameters and  biased
       by  the  four  1D GL_CONVOLUTION_FILTER_BIAS parameters.  (The scale and
       bias  parameters   are   set   by   glConvolutionParameter   using   the
       GL_CONVOLUTION_1D  target  and the names GL_CONVOLUTION_FILTER_SCALE and
       GL_CONVOLUTION_FILTER_BIAS.  The parameters themselves  are  vectors  of
       four values that are applied to red, green, blue, and alpha, in that or‐
       der.)  The R, G, B, and A values are not clamped to [0,1]  at  any  time
       during this process.

       Each  pixel  is  then  converted  to  the  internal  format specified by
       _param2.  This conversion simply maps the component values of the  pixel
       (R,  G,  B,  and  A) to the values included in the internal format (red,
       green, blue, alpha, luminance, and intensity).  The mapping is  as  fol‐
       the resulting pixels are stored in floating-point  rather  than  integer
       format.

       Pixel  ordering  is  such  that lower x screen coordinates correspond to
       lower i filter image coordinates.

       Note that after a convolution is performed, the resulting  color  compo‐
       nents are also scaled by their corresponding GL_POST_CONVOLUTION_c_SCALE
       parameters and biased by their corresponding  GL_POST_CONVOLUTION_c_BIAS
       parameters  (where  c  takes on the values RED, GREEN, BLUE, and ALPHA).
       These parameters are set by glPixelTransfer.

NOTES
       glCopyConvolutionFilter1D is present only if GL_ARB_imaging is  returned
       when glGetString is called with an argument of GL_EXTENSIONS.

ERRORS
       GL_INVALID_ENUM is generated if targe is not GL_CONVOLUTION_1D.

       GL_INVALID_ENUM is generated if _param2 is not one of the allowable val‐
       ues.

       GL_INVALID_VALUE is generated if _param5 is less than  zero  or  greater
       than  the  maximum  supported  value.   This  value  may be queried with
       glGetConvolutionParameter  using  target  GL_CONVOLUTION_1D   and   name
       GL_MAX_CONVOLUTION_WIDTH.

       GL_INVALID_OPERATION  is  generated if glCopyConvolutionFilter1D is exe‐
       cuted between the execution of glBegin and the  corresponding  execution
       of glEnd.

ASSOCIATED GETS
       glGetConvolutionParameter, glGetConvolutionFilter

SEE ALSO
       glConvolutionFilter1D, glConvolutionParameter, glPixelTransfer

                                                  GLCOPYCONVOLUTIONFILTER1D(3G)