Wethern's Law:
   Assumption is the mother of all screw-ups

Concept 5.2 : A simple Triangulation Example 
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Idea:
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Shown to your left is a annulus.  The lazy mans way of 
rendering this scene would be to first draw a big white 
square the size of the outer perimeter and then a small 
black squre inside it!! 
Obviously we are here to learn to do things the correct
way using triangulation.

KeyBoard Options
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The following keyboard options work:
'w' toggles between wireframe and solid polygon mode
'e' toggles between rendering the internal edges
of the triangles and rendering only the extermities
of the triangles which make up the annulus

Do the following :
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click 'w' anywhere in the rendering area.  This shows
you the annulus in a wireframe mode.  Notice how the
object has been triangulated.  Also the code window above
shows that the triangles are rendered in a consistent 
CCW fashion. The triangle vertices have been selected such
as to form two equal triangles per side of the annulus.

While in the wireframe mode click the 'e' button on the 
keyboard. Notice how the inside edges of the triangle vanish.  
When you click 'e' the internal edges are suppressed
by issuing the command glEdgeFlags(FALSE);

Points to Remember:
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  o  Generate small but equal sized triangles
  o  Remember to orient your triangles while rendering 
     them so they are rendered the same way.  i.e. CCW or 
     CW i.e. Counter Clock Wise vertex specification or 
     Clock Wise vertex specification.
  o  Make use of glEdgeFlag() with the argument set to 
     FALSE if you wish to render inside edges invisible.