Nurbs Tesselation

Does anyone have any references or ideas about how OpenGL goes about tesselating trimmed NURBS surfaces ? I am looking for theory or papers that may cover this subject.


I’m looking it too… Optimizer does it, but only works under Visual c++ (or irix… :P) I need a c++ builder version…

You could have a look at the Mesa source code. There should be the code for it, maybe it is documented :wink:

I was looking for a tesselator too, because the OpenGL tesselator doesn’t work for me when you have e.g. a cylindrical NURB. Now it is unlimited in u direction, but bound in the v direction on top and bottom (of the cylinder). There I wanted to give a loop to OpenGL, but it is only a line in this case. That is not understood by the OpenGL tesselator…
Have you got links to good tesselators?

I could do with some papers on Trimmed surfaces, Thats the one thing I’ve not yet implimented in my own tessellator. I’ve been mainly looking at constructing surfaces from NURBS curves as well as others based on tangents, ie cardinal splines. If any one has any good links…

Hi !

Have a look at

The IRIT libraries contains all kinds of spline functions, 2D,3D nurbs (also trimmed), triangular splines, and lots of other stuff.