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<TITLE>Re: [vtk-developers] Polyhedral challenge</TITLE>
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<FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>Hi Will,<BR>
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Can I get access to that repository? I misread this thinking it was already going into cvs... I am currently trying to get the latest exodus API in which handles polyhedra. I’d be happy to help test from my end (although I’d be happy just to read and write for now...)<BR>
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Thanks,<BR>
Nathan.<BR>
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On 2/18/10 9:38 AM, "Will Schroeder" <<a href="will.schroeder@kitware.com">will.schroeder@kitware.com</a>> wrote:<BR>
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</SPAN></FONT><BLOCKQUOTE><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>Hua and I have made progress on adding a vtkPolyhedron cell to VTK. We have a wiki page describing the tasks (which will take some time to implement depending on our funding and schedule <a href="http://www.vtk.org/Wiki/VTK/Polyhedron_Support">http://www.vtk.org/Wiki/VTK/Polyhedron_Support</a>). We are using the interpolation method of mean value coordinates which Hua has already implemented, thus far it is a super algorithm. Comments are welcome.<BR>
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We are now starting the integration into vtkUnstructuredGrid. If you are interested let me know and at the appropriate point we can make our git repository available.<BR>
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On Thu, Jan 21, 2010 at 6:53 AM, Will Schroeder <<a href="will.schroeder@kitware.com">will.schroeder@kitware.com</a>> wrote:<BR>
</SPAN></FONT><BLOCKQUOTE><FONT FACE="Calibri, Verdana, Helvetica, Arial"><SPAN STYLE='font-size:11pt'>FYI-<BR>
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Hua Yang and I are adding a new cell type to VTK: the polyhedral cell. This is mainly to support our CFD friends who like to compute flow solutions using flux approaches (balance mass and energy in and out of a region).<BR>
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One of the key questions is how to interpolate across the interior of such a cell. In the past I have seen two typical approaches 1) tessellate the polyhedron into tetrahedra, and then use the tetrahedra to interpolate; and 2) use a 1/r**2 (or similar weighting function) to interpolate from the cell nodes to an interior point in the polyhedron. Both approaches have problems with continuity, etc.<BR>
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We are also researching other approaches. However in the interest of completeness, if anybody has suggestions for alternatives we'd love to hear about them.<BR>
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Will<BR>
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