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GLUTESSBEGINPOLYGON()                                    GLUTESSBEGINPOLYGON()

NAME
       gluTessBeginPolygon - delimit a polygon description

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

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
       gluTessBeginPolygon/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 contour (the last vertex of each contour is automatically linked
       to the first). See the gluTessVertex, gluTessBeginContour, and
       gluTessEndContour 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
       gluTessCallback for descriptions of the callback functions.

EXAMPLE
       A quadrilateral with a triangular hole in it can be described as
       follows:

       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()