[vtkusers] Smoother surfaces after Marching Cubes-- vertex normals

[Jim Carroll]

Hi,

I'm using Marching cubes, and when I render I can't figure out how to get one
normal per vertex, instead of one normal per triangle.  

Ideally the direction of the normal for a vertex would be the average of the
normals of all the triangles that share that vertx.

Can VTK do this for me?

There's a good example of how the appearance changes at the bottom of this page:
   http://astronomy.swin.edu.au/~pbourke/modelling/polygonise/

Thanks,
-Jim