[vtkusers] Clipping geometry

[Brent Burton]

Hello all,

I have two PolyData sets, one contains line segments and the other has an
isosurface.  Both sets are large, and to better manipulate the
interesting quadrant of the volume I need to cull the rest.

After trying several different clipping/extraction techniques, I got
vtkClipPolyData working with a vtkImplicitBoolean function consisting of
two vtkPlanes.  This clipper script is in TCL and works very well.

So my question to the list:  Is the above clipper the most efficient
way to trim geometric data?  Does anybody have a brief description
of where the other filters (vtkExtractGeometry, vtkExtractVOI, etc)
are more appropriate (and maybe more efficient) than vtkClipPolyData?

I appreciate any comments on this.

-Brent