[vtkusers] Computing curvature of a surface

[John Biddiscombe]

Philipp

> it's a funny coincidence that I hadn't been touched my curvature
> code for a long time, but have been working this week on  the  changes to
make it compatible
> with the way vtk4.x handles Scalars. (Not without struggle, as my post
> on Monday shows).

I've converted a ton of classes and will gladly do your curvature class too
if you wish (I have a copy here). (and then add it to vtkGraphics if you
like. It's a useful addition I'm sure).

JB