[vtkusers] vtkPolyData::GetCellNeighbors(...) question

[Nils Hanssen]

Hi,

I want to check if a polymesh consisting of triangles or triangle strips is
closed or not (necessary for volume computation).
For that, I just check, if every triangle cell has exactly 3 triangle
neighbors.

To be sure, I first triangulate the polymesh (to get rid of the strips) and
then call ->BuildCells() and ->BuildLinks() on the mesh.
Then I traverse trough the triangles of the mesh and check for each edge, if
it has exactly one other triangle that joins this edge.
For that, I provide the current cell ID, the two point IDs of the current
edge and the list that is filled with the ID(s) of adjacent triangle cells.

I am pretty sure that the mesh that I am testing is closed. But just for the
first triangle, another adjacent triangle cannot be found.
Do I miss something? Do I have to preprocess the polydata in some other way?

Thank you for any suggestions!

Regards,
Nils

-------------------------
Nils Hanssen
Surgical Systems Laboratory
research center c ae sa r
Friedensplatz 16
53111 Bonn
fon: +49-228-9656-249
fax: +49-228-9656-111
http://www.caesar.de/ssl



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20020507/7d043853/attachment.htm>