[Plib-devel] simple tessellation help

[Peijing <est...@si...>]

Hi,
I'm new to plib and I need to create a rectangular polygon with a triangular 
hole like this:
_______
|           |
|__/\___|

but I do not know how to do this with plibs. I've got some examples from the 
opengl redbook and I'm looking for a plib equivalent of it.
Could someone enlighten me regarding how to go about doing this or any 
online references I can refer to?

The opengl code is such:
 GLUtesselator *tobj;

  GLdouble rect[4][3] = {50.0, 50.0, 0.0,
                          200.0, 50.0, 0.0,
                          200.0, 200.0, 0.0,
                          50.0, 200.0, 0.0};
   GLdouble tri[3][3] = {75.0, 75.0, 0.0,
                         125.0, 175.0, 0.0,
                         175.0, 75.0, 0.0};

   glClearColor(0.0, 0.0, 0.0, 0.0);

   startList = glGenLists(2);

   tobj = gluNewTess();
   gluTessCallback(tobj, GLU_TESS_VERTEX,
                   glVertex3dv);
   gluTessCallback(tobj, GLU_TESS_BEGIN,
                   beginCallback);
   gluTessCallback(tobj, GLU_TESS_END,
                   endCallback);
   gluTessCallback(tobj, GLU_TESS_ERROR,
                   errorCallback);

   /*  rectangle with triangular hole inside  */
   glNewList(startList, GL_COMPILE);
   glShadeModel(GL_FLAT);
   gluTessBeginPolygon(tobj, NULL);
      gluTessBeginContour(tobj);
         gluTessVertex(tobj, rect[0], rect[0]);
         gluTessVertex(tobj, rect[1], rect[1]);
         gluTessVertex(tobj, rect[2], rect[2]);
         gluTessVertex(tobj, rect[3], rect[3]);
      gluTessEndContour(tobj);
      gluTessBeginContour(tobj);
         gluTessVertex(tobj, tri[0], tri[0]);
         gluTessVertex(tobj, tri[1], tri[1]);
         gluTessVertex(tobj, tri[2], tri[2]);
      gluTessEndContour(tobj);
   gluTessEndPolygon(tobj);
   glEndList();
   gluDeleteTess(tobj);

Any help is appreciated.

Thanks,
EL