Andy, ParaView uses vtkPolyhdron data-structure to store polyhedron. As you can read on this page <https://www.vtk.org/doc/nightly/html/classvtkPolyhedron.html#details>, vtkPolyhdron requires: *"The polyhedron should be watertight, non-self-intersecting and manifold (each edge is used twice)."*
Clearly, your cell here is not watertight (see attached picture), so I fear you won't be able to process it correctly with VTK based tools. Best, * Joachim Pouderoux*, Ph.D. *Technical Lead - Scientific Visualization Team* *Kitware SAS <http://www.kitware.fr>* Le jeu. 7 juin 2018 à 17:36, Andrew Parker via ParaView < [email protected]> a écrit : > Hi, > > I have attached two files. One is a single-cell complex polyhedron which > I wish to be able to use and visualise (as is, without tessellation and > tetrahedralization). Using 5.5.0 this fails to slice/cut in paraview in > any major plane. Paraview complains about non-manifold (under-connected) > edges. To debug I wrote out as a vtkPolyData containing all the faces of > this single cell polyhedron. This polyData Slices/cuts just fine. All > faces added to the vtp file as VTK_POLYGON, likewise are added as a > face-stream when added as a VTK_POLYHEDRON to the vtu file. To be clear, I > write the faces out to the vtp in the same loop I build the faces for the > single cell vtu mesh, so they are carbon copies of the faces, including > numbering, ordering etc. I am aware there are more vertices in the file > than need be (27 rather than 19), but it was easier... > > My working assumption is that there is no problem visualising and working > with cells of this type (non-convex) in paraview (real use cases includes a > mesh with many of these types of cells). Clarity on this point would also > be good… > > I believe paraview should work for concave cells and I suspect it’s a bug > (either in paraview or my face-data) because if I use 5.4.1 (or indeed > 5.2.0) I can clip the singleCell in the x-plane (with inside-out flag > on/off) and I get the expected results. However, in the y and z planes I do > not get the expected results and those versions either return an empty > result or the whole cell. I get no results in 5.5.0 regardless of plane. > Finally, I get no results in 5.5.1 either. So it sort of used to work in > earlier versions depending on the plane of slicing, but now does not. > > I’m not sure what I’m doing wrong, can somebody shed some light or spot an > error in the attached file? This may be linked to: > > https://gitlab.kitware.com/paraview/paraview/issues/18003 > > Thanks again, > Andy > > _______________________________________________ > Powered by www.kitware.com > > ParaView discussion is moving! Please visit > https://discourse.paraview.org/ for future posts. > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the ParaView Wiki at: > http://paraview.org/Wiki/ParaView > > Search the list archives at: http://markmail.org/search/?q=ParaView > > Follow this link to subscribe/unsubscribe: > https://public.kitware.com/mailman/listinfo/paraview >
_______________________________________________ Powered by www.kitware.com ParaView discussion is moving! Please visit https://discourse.paraview.org/ for future posts. Visit other Kitware open-source projects at http://www.kitware.com/opensource/opensource.html Please keep messages on-topic and check the ParaView Wiki at: http://paraview.org/Wiki/ParaView Search the list archives at: http://markmail.org/search/?q=ParaView Follow this link to subscribe/unsubscribe: https://public.kitware.com/mailman/listinfo/paraview
