Hi list,
when using vtkSurfaceNets3D recently I have discovered that the BoundaryLabels Scalars correctly include the two numeric labels for the inside/outside areas of the input image, but their order does not seem to match the normals of the generated triangles.
For example, given labels 1 and 2, in the generated mesh surface, a few triangles seem to have normals that point to 1, while most others point to 2, even though the order of the BoundaryLabels for these triangles is constant and always shows e.g. “1 2” but not “2 1” for the triangles with normals that show in the opposite direction.
Is there any chance that this can be easily included/fixed? Obviously it would even be better if all normals of a mesh separating two structures only (no more junctions) would always point into the same direction such that the boundary label order indeed can stay the same for all related triangles.
If this is not easily possible then I would think one has to loop over each generated triangle, make a small step into the normal direction, inspect the underlying voxel of the input image and correct manually.
Any hints are welcome.
Thanks,
sophonet