[vtkusers] Create surface from isolines?

[Chris Scharver]

At 1:04 AM +0200 04/26/2003, Charl P. Botha wrote:
>vtkRuledSurfaceFilter could do the trick if I understand your explanation
>correctly.

Aha! Thank you for pointing me in exactly the right direction! This was just where I need to go! I had to fix the ordering, so here's what else I did...

I am trying to avoid resampling as much as possible. The lines for vtkRuledSurfaceFilter need to have an equal number of points, so I had to make a concession there. The output from vtkCutter is broken into separate lines, so I added vtkStripper to merge them together. Because the clipped lines were made separately, they are not correctly aligned for use by vtkRuledSurfaceFilter. However, the visual result indicated that I could cheat by flipping the ordering for one of the lines. I had to fudge things by using vtkPolyData::reverseSense(). I have a beautiful, solidly clipped object now! I'll try to clean up my code to contribute in case others may find it to be a useful example.

I less kludgy approach would involve sorting the points of the lines so they align properly when applying the filter. I'll have to check to see how well I can manage using vtkDepthSortPolyData to do just that.

Thanks tremendously!
Chris
--
Chris Scharver
Electronic Visualization Laboratory
The University of Illinois at Chicago
Ph: 312-996-3002   FAX: 312-413-7585
<http://www.evl.uic.edu/scharver/>