[vtkusers] control opacity/transparent of cell/vertex in polydata by scalar data

[Gao, Yi]

Hi all,

I have this simple visualization scenario:

Assuming I have a triangulated mesh (in vtkPolyData) of N vertexes and
F triangles.
I also have N scalar numbers, each number is associated with each vertex.

I can display the polydata's vertexes using the scalar data in, say
HSV colormap. However, I also want to use them to control the
transparent/opacity of the vertexes. For instance, a low scalar value
should be a very transparent blue color; while a large number
indicates that vertex to be non-transparent red.

I didn't find examples on such topic... could I get some hint? any
hint or link would be appreciated!

Cheers,
yi