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Student_1138
01-07-2005, 01:55 AM
:confused:
I need to determine a set of points which lie on a surface (x,y,z coordinates for each point in the u and v directions) when given a knot
vector, control points and weights in NURBS format. I know that there are NURBS evaluators in openGL (glEvalCoord), similar to using a vertex, but I do not know how to obtain the actual coordinates for each point that it has generated from the evaluator (for each u and/or v input). Any help that you could provide would be helpful. Thank you.

knackered
01-07-2005, 02:29 AM
Look up "glFeedbackBuffer".

V-man
01-07-2005, 05:34 AM
Originally posted by Student_1138:
I know that there are NURBS evaluators in openGL (glEvalCoord)That's not a NURBS evaluator. If you want NURBS, look into glu.

Or look for a 3rd party library. I think there was one called NURBS++ and it will let you have the tesselated geometry.

A quick search gives
http://libnurbs.sourceforge.net/