gluTessBeginPolygon()                       gluTessBeginPolygon()

NAME    [Toc]    [Back]

       gluTessBeginPolygon - delimit a polygon description

SYNOPSIS    [Toc]    [Back]

       void gluTessBeginPolygon(
               GLUtesselator* tess,
               GLvoid* data );

PARAMETERS    [Toc]    [Back]

       Specifies  the  tessellation object (created with gluNewTess()).
  Specifies a pointer to user polygon data.

DESCRIPTION    [Toc]    [Back]

       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  perpolygon
 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    [Toc]    [Back]

       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    [Toc]    [Back]

       gluNewTess(3),  gluTessBeginContour(3),  gluTessVertex(3),
       gluTessCallback(3), gluTessProperty(3),  gluTessNormal(3),
       gluTessEndPolygon(3)



                                            gluTessBeginPolygon()