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GLPOLYGONSTIPPLE(3G)                                                                    GLPOLYGONSTIPPLE(3G)



NAME
       glPolygonStipple - set the polygon stippling pattern


C SPECIFICATION
       void glPolygonStipple( const GLubyte *mask )


PARAMETERS
       mask  Specifies  a  pointer  to a 32x32 stipple pattern that will be unpacked from memory in the same
             way that glDrawPixels unpacks pixels.

DESCRIPTION
       Polygon stippling, like line stippling (see glLineStipple), masks out certain fragments  produced  by
       rasterization, creating a pattern.  Stippling is independent of polygon antialiasing.

       mask  is  a pointer to a 32x32 stipple pattern that is stored in memory just like the pixel data sup-plied supplied
       plied to a glDrawPixels call with height and width both equal to 32, a pixel of  GL_COLOR_INDEX,  and
       data  type of GL_BITMAP.  That is, the stipple pattern is represented as a 32x32 array of 1-bit color
       indices  packed  in  unsigned  bytes.   glPixelStore   parameters   like   GL_UNPACK_SWAP_BYTES   and
       GL_UNPACK_LSB_FIRST  affect the assembling of the bits into a stipple pattern.  Pixel transfer opera-tions operations
       tions (shift, offset, pixel map) are not applied to the stipple image, however.

       To  enable  and  disable   polygon   stippling,   call   glEnable   and   glDisable   with   argument
       GL_POLYGON_STIPPLE.  Polygon  stippling  is initially disabled. If it's enabled, a rasterized polygon
       fragment with window coordinates xw and yw is sent to the next stage of the GL if and only if the (xw
       mod  32)th bit in the (yw mod 32)th row of the stipple pattern is 1 (one).  When polygon stippling is
       disabled, it is as if the stipple pattern consists of all 1's.

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

ASSOCIATED GETS
       glGetPolygonStipple
       glIsEnabled with argument GL_POLYGON_STIPPLE

SEE ALSO
       glDrawPixels(3G), glLineStipple(3G), glPixelStore(3G), glPixelTransfer(3G)




                                                                                        GLPOLYGONSTIPPLE(3G)