glPolygonStipple

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  32×32 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 32×32 stipple pattern that is stored in memory
       just like the pixel data supplied 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	32×32
       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
       operations (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	 dis-
       abled.  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	(xwmod32)th bit in the (ywmod32)th row of the stipple pattern
       is 1 (one).  When polygon stippling is disabled, it is as if the stip-
       ple 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)