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GLUTESSBEGINPOLYGON()					 GLUTESSBEGINPOLYGON()

NAME
       gluTessBeginPolygon - delimit a polygon description

C SPECIFICATION
       void gluTessBeginPolygon( GLUtesselator*	tess,
				 GLvoid* data )

       delim $$

PARAMETERS
       tess  Specifies the tessellation	object (created	with gluNewTess).

       data  Specifies a pointer to user polygon data.

DESCRIPTION
       gluTessBeginPolygon  and	 gluTessEndPolygon delimit the definition of a
       convex, concave or self-intersecting polygon. Within each gluTessBegin-
       Polygon/gluTessEndPolygon pair, there must be  one  or  more  calls  to
       gluTessBeginContour/gluTessEndContour.	Within each contour, there are
       zero or more calls to gluTessVertex. The	vertices specify a closed con-
       tour (the last vertex of	each contour is	automatically  linked  to  the
       first).	See the	gluTessVertex, gluTessBeginContour, and	gluTessEndCon-
       tour reference pages for	more details.

       data is a pointer to a user-defined data	structure. If the  appropriate
       callback(s)  are	 specified (see	gluTessCallback), then this pointer is
       returned	to the callback	function(s). Thus, it is a convenient  way  to
       store per-polygon information.

       Once  gluTessEndPolygon	is called, the polygon is tessellated, and the
       resulting triangles are described through callbacks.  See  gluTessCall-
       back for	descriptions of	the callback functions.

EXAMPLE
       A  quadrilateral	 with a	triangular hole	in it can be described as fol-
       lows:

       gluTessBeginPolygon(tobj, NULL);
	gluTessBeginContour(tobj);
	  gluTessVertex(tobj, v1, v1);
	  gluTessVertex(tobj, v2, v2);
	  gluTessVertex(tobj, v3, v3);
	  gluTessVertex(tobj, v4, v4);
	gluTessEndContour(tobj);
	gluTessBeginContour(tobj);
	  gluTessVertex(tobj, v5, v5);
	  gluTessVertex(tobj, v6, v6);
	  gluTessVertex(tobj, v7, v7);
	gluTessEndContour(tobj); gluTessEndPolygon(tobj);

SEE ALSO
       gluNewTess,   gluTessBeginContour,   gluTessVertex,    gluTessCallback,
       gluTessProperty,	gluTessNormal, gluTessEndPolygon

							 GLUTESSBEGINPOLYGON()

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