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<p class="MsoNormal">All,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m sure I’m missing something here, so please knock me up alongside the head and point it out.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I load a sideset (surface) from an Exodus file. I end up with a bunch of quads that Paraview conveniently created for me from the surface. I need to calculate a Normal vector for each of these quads. I have tried:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Generate surface normal – this is greyed out (wants poly data?)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Delaunay 3D on this to generate poly data, which I could then hopefully run Generate surface normal on, but it was still greyed<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Tried Normal Glyphs which gave me point Normal vectors but gave me a bunch of Triangle and Polygon elements – I’m not sure what’s going on here.<o:p></o:p></p>
<p class="MsoNormal"> PointDataToCellData to get GlyphVector for each Cell <o:p>
</o:p></p>
<p class="MsoNormal"> Python Calculator and ask for area(inputs[0]) the Polygon elements all get an Area of -1<o:p></o:p></p>
<p class="MsoNormal"> Calculator to get Area_X as product of GlyphVector_X and Area<o:p></o:p></p>
<p class="MsoNormal"> Threshold on Area_X > 0 - don’t want negative areas or some boundary cells with GlyphVector_X as negative<o:p></o:p></p>
<p class="MsoNormal"> Python Calculator to get sum(Area_X)<o:p></o:p></p>
<p class="MsoNormal"> This number appears to be about half of my expected number<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">These must be an easier way. I’m not a vtk guru. When I first load my surface, is there some vtk routine I could call within a Programmable filter to get the cell normal?????
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Alternatively, anyone got an easier way to skin this cat?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for any hints you may have.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dennis<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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