Null triangles

[Roger H. <rog...@mi...>]

What do you all think on this. When certain tri-grids get turned into  
tri-meshes, they sometimes generate null triangles because two of the  
four corners of one of the grid quadrilateral are coincident. For  
instance the original QuickDraw3D sample code generated a sphere and a  
cone with Tri-grids and at the poles of the sphere and the point of  
the cone, this happened. Would it be worthwhile to not generate these  
null triangles, or should the tri-mesh constructor function filter  
them out or should we continue to filter them out every time we render  
or do processing of triangulated  data such as when doing CSG  
calculations.

Roger Holmes.