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<div>Hello,</div>
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<div>-- I am using vtk 4.4.</div>
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<div>-- I have a triangular surface mesh as input vtkPolyData</div>
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<div>-- I intersect the surface with a cartesian plane ( xy , yz or xz ) and obtain a curve --- i use the vtkContourFilter to extract this curve.</div>
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<div>-- The curve thus extracted is in the form of vtkPolyData.</div>
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<div>-- <em><strong>Now how can I compute the curve normals and curve tangents at each point on this curve ?</strong></em></div>
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<div> --- vtkPolyDataNormals filter does not work for curves according to the documentation.</div>
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<div> --- Does anyone know if there is a VTK filter to achieve this task ?</div>
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<div> --- I tried computing the normals myself from the Lagrangian Interpolation curve passing thru the point and its 1-neighbors. </div>
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<div> ------ But i faced one more problem - <em><strong>How do i find the neighboring vertices of a point in vtkPolyData? </strong></em></div>
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<div> ----------- i tried vtkPolyData::GetPointCells() but this does not seem to work for curves. Any ideas ????</div>
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<div>Thanks in Advance.</div>
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<div>Regards,</div></div>
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<div>Deepak Roy</div>
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