[vtkusers] Need for spherical to cartesian nonlinear transformation.

[Roland Schwarz]

Hi David,

> I've already written one, but wasn't sure if it was worth committing.
> I can commit it over the weekend and email you a copy later today.  It
> works as you describe, it is derived directly from vtkAbstractTransform
> and it defines the inverse analytically.

this are very good news. Thank you so much.

Roland