Hi Chipp,

> I understand what you're saying is that because you have the ACTUAL representation of the surface
> (and not a fake poly rep), then you can easily calculate the exact normals on export.

Yup, that's exactly right - that can be one of the advantages of NURBS modeling, that you basically have an underlying master accurate version of the object that can be used as a reference for various calculations. It especially helps when there are things like exact spheres or cylinders involved in the model.

The shading working in this way can help in other cases too like generating rough low polygon versions of objects, even rough polygons tend to shade nicely since the shading comes from the accurate original surface and not just averaged between polygons that are themselves approximations.


> Michael, am I correct in assuming you will subdivide accurately a curved surface at an even
> higher angular density (lower angle) if the Divide larger than setting requires it?

Yup, that's correct - "Divide larger than" can be used to force further subdivisions than what the angle parameter would do by itself.

Just one thing to note is the drop-down on the right side of "Divide larger than" plays a role too, it controls whether that will be applied to just curved surfaces, or whether it will be applied to all surfaces.

Using "Divide larger than" can especially help for shapes that are fairly wide but only very shallowly curved, often times if the shape has a big yet very shallow curvature it tends to require a very tight angle to get a lot of subdivisions on it, that's when the distance based "Divide larger than" can be used to chop things up additionally.

- Michael