[vtkusers] Fwd: How to smooth (or filter) polydata scalars?

[Kevin H. Hobbs]

On Wed, 2009-01-14 at 13:38 +0100, Fabio Meneghini wrote:
> 
> Thank you very much for your reply. I really appreciated it!

You're welcome.

> So, for every vertex of the polydata,

"Vertex" has a specific meaning in VTK it means a cell with one point.
I'm not much of a jargon nut but this could prevent some confusion as
you search through classes.

>   I could compute the mean of the scalar values of its neighbors
> (possibly with some weights, depending on their distance from the
> current vertex, and then replace the actual scalar value of current
> vertex with the mean.

In general yes that's how I'd do it. Do the replacement in a temporary
scalar array or calculate the average from a copy of the scalar array.
That way you won't contaminate the average of the neighbors of later
points with the average of the neighbors of earlier points.

> waiting for a better suggestion about wich classes do this job
> better, 
> Thanks again for the hint...
> 

Use of the gradient or gradient magnitude filters might help you with
highpass filters.

> Fabio

I'm attaching code that does point (position) smoothing in a particular
way that I need. It should help you walk the polydata.
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