GLUBEGINPOLYGON(3G) GLUBEGINPOLYGON(3G)

gluBeginPolygon, gluEndPolygon - delimit a polygon description

void gluBeginPolygon( GLUtesselator* tess )



void gluEndPolygon( GLUtesselator* tess )













  

  
Specifies the tessellation object (created with gluNewTess).










gluBeginPolygon and gluEndPolygon delimit the
    definition of a nonconvex polygon. To define such a polygon, first call
    gluBeginPolygon. Then define the contours of the polygon by calling
    gluTessVertex for each vertex and gluNextContour to start each
    new contour. Finally, call gluEndPolygon to signal the end of the
    definition. See the gluTessVertex and gluNextContour reference
    pages for more details.


Once gluEndPolygon is called, the polygon is tessellated,
    and the resulting triangles are described through callbacks. See
    gluTessCallback for descriptions of the callback functions.








This command is obsolete and is provided for backward
    compatibility only. Calls to gluBeginPolygon are mapped to
    gluTessBeginPolygon followed by gluTessBeginContour. Calls to
    gluEndPolygon are mapped to gluTessEndContour followed by
    gluTessEndPolygon.








A quadrilateral with a triangular hole in it can be described like
    this:


gluBeginPolygon(tobj);
  

   gluTessVertex(tobj, v1, v1);
  

   gluTessVertex(tobj, v2, v2);
  

   gluTessVertex(tobj, v3, v3);
  

   gluTessVertex(tobj, v4, v4); gluNextContour(tobj, GLU_INTERIOR);
  

   gluTessVertex(tobj, v5, v5);
  

   gluTessVertex(tobj, v6, v6);
  

   gluTessVertex(tobj, v7, v7); gluEndPolygon(tobj);








gluNewTess, gluNextContour, gluTessCallback,
    gluTessVertex, gluTessBeginPolygon,
  gluTessBeginContour