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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>Dear All,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>I am creating an instance of <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'> vtkCutter *pCrossSection ; from vtkUnstructuredGridReader
*pMeshReader<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>and <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>vtkClipPolyData *pXSectionClipper ; from vtkGeometryFilter
*pGeometry ;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>and merging them into<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'> vtkAppendPolyData *pCutMeshData ;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>The problem is that, when I do a colour plot of the scalar
I get a bad effect at an internal boundary (where the boundary is formed by
having coincident “nodes” in a finite element mesh that are in
congruent elements – this forms a no flow boundary in the mesh). The rendering
of the colour contouring works perfectly when the vtkUnstructuredGrid is put
through the vtkGeometryFilter, but the coincident nodes are merged (I think)
when the mesh is cut (using the object listed above) and the colour mapping is fuzzy
along the boundary (whereas it should be a sheer change in colour).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>My questions are:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>would merging explain the phenomenon described above?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>is there a way to turn off point merging in vtkCutter
& vtkClipPolyData?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>Regards,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'>Jim <o:p></o:p></span></font></p>
<p class=MsoNormal><b><font size=3 face=Arial><span lang=EN-IE
style='font-size:12.0pt;font-family:Arial;font-weight:bold'>James C Robinson</span></font></b><font
size=2 face=Arial><span lang=EN-IE style='font-size:10.0pt;font-family:Arial'>,
PhD, Chartered Engineer,</span></font><span lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face=Wingdings><span lang=EN-IE
style='font-size:12.0pt;font-family:Wingdings'>+</span></font><span lang=EN-IE> </span><font
size=2 face=Arial><span lang=EN-IE style='font-size:10.0pt;font-family:Arial'>42
Rivergrove,</span></font><span lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'> Glanmire,</span></font><span lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'> Co. <st1:place w:st="on"><st1:City w:st="on">Cork</st1:City></st1:place>,</span></font><span
lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-IE style='font-size:
10.0pt;font-family:Arial'> <st1:place w:st="on">Eire</st1:place></span></font><span
lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face="Wingdings 2"><span lang=EN-IE
style='font-size:12.0pt;font-family:"Wingdings 2"'>'</span></font><span
lang=EN-IE> +353 21 4822028<o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-IE
style='font-size:12.0pt'> +353 87 2393010<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Wingdings 2"><span lang=EN-IE
style='font-size:12.0pt;font-family:"Wingdings 2"'>6</span></font><span
lang=EN-IE> +353 21 4822028<o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face=Wingdings><span lang=EN-IE
style='font-size:12.0pt;font-family:Wingdings'>-</span></font><span lang=EN-IE> <font
color=blue><span style='color:blue'>j.robinson@kepler-systems.com</span></font> </span><span
lang=EN-IE><o:p></o:p></span></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=EN-IE
style='font-size:12.0pt'><o:p> </o:p></span></font></p>
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