[vtkusers] Probs with cell search

[David C Thompson]

On Wed, 2006-06-07 at 17:15 +0200, Hentschel, Bernd wrote:
> I've got a problem with the cell search algorithm in VTK (i.e.,
> vtkPointSet::FindCell(...)). In the past I have encountered several data
> sets in which the FindCell routine returned no cell although the point
> in question was definitely in the domain. ...
> I already had a quick glance at the marching scheme implemented inside
> FindCell and it seems that the marching process very often reaches its
> maximum distance of 12 cells before the correct cell is found.
> Since I need this to work quite urgently, the next question would be if
> there is some kind of obvious workaround? If need be I can provide
> example code and test data to whomever is interested in this.

Is your mesh non-convex? If so, that can cause FindCell to fail. I
attached a patch to bug 2054
( http://www.vtk.org/Bug/bug.php?op=show&bugid=2054&pos=5 ) but the
Kitware folks haven't got around to applying the fix yet. You might try
the patch and see if it works.

	David

-- 
David Thompson, MS 9152                (925)294-2537
Sandia National Laboratories           dcthomp at sandia.gov
Distributed Visualization Systems 8963 Bldg/Rm 915/N144
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