Also PaQ, weren't you recently talking about using Rhino some too? In Rhino there is a command called MeshToNurb that will do this (convert each poly face to a flat trimmed plane, not a sub-d conversion).

Just keep in mind that you can end up with an extremely heavy NURBS model with that method, because there is more overhead to how trimming boundaries work in NURBS models - there's stuff like a 3D edge curve, as well as a 2D edge curve, and the curves are actual splines that are created in addition to vertices.

In a poly mesh model, the edges are more lightweight and basically just implied as straight lines connecting each vertex, so it's more efficient with polys to have something like 300,000 edges in a mesh, whereas 300,000 edges in a NURBS b-rep is huge.

Of course since each edge in a NURBS brep is a general spline you can get a whole lot more out of a single edge in NURBS because it can be an actual curved piece of geometry and not just a line between 2 vertices. That's why you can get a complex model in a NURBS brep with something more like 5,000 edges or faces since each individual edge or face describes a bigger curved piece of the model. But by making each surface a little plane and each edge just a line you're basically negating that.

- Michael