[vtkusers] Help with 3D triangulation process

[Moore, Brett]

Hi, 
Now that I can compile my program, I have run into a bit of a problem with my process.  I would like to triangulate a 3D point cloud to recover the object's surface.  (Data were obtained using laser scanninng.)

My first attempt works (sort of):

1.  Build a vtkPointSet
2.  Pass the point set to vtkDelaunay3D
3.  Pass the vtkDelaunay3D output to vtkDataSetMapper
4.  Render

The method's output does not look very good.  Furthermore, the dataset consists of 500,000 data points and should be a prime candidate for mesh optimization.  (The points are sampled at a high resolution - large regions of the object will be approximately planar).  I attempted this:

3.  Pass the vtkDelauany3D output to vtkUnstructuredGridToPolyDataFilter
4.  Apply a vtkTriangleFilter
5.  Decimate
6.  Pass the decimated mesh to vykPolyDataMapper
7.  Render

I realize that there are several things wrong with the above (but maybe it outlines the process I need).  To summarize, I believe I need a means to extract 2D triangles from the triangulated tetrahedral cells.  (thus the vtkUnstructuredGridToPolyDataFilter step -  but this class seems to be abstract).  Once the 2D triangles are obtained, I think the decimation and rendering steps are straightforward.

I appreciate any guidance.
Thanks, Brett