vtkCellDerivatives dereferences NULL pointer and crashes
This issue was created automatically from an original Mantis Issue. Further discussion may take place here.
When I first tried to compute the vorticity of a velocity vector field using the vtkCellDerivatives filter, I got a segfault. If I'm reading <paraview_source>/VTK/Graphics/vtkCellDerivatives.cxx correctly, the block of code on lines 77-94 allocates storage for the computed vorticity vector field (outVectors) only if there is an input scalar array, even if VectorMode is set to COMPUTE_VORTICITY. So if I give the filter a vector field without a scalar field and ask for vorticity, it tries to write vorticity into the outVectors object, which is NULL, and it crashes. (line 193)