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<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2>Hi,</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>I want to
check if a polymesh consisting of triangles or triangle strips is closed or not
(necessary for volume computation).</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>For that, I
just check, if every triangle cell has exactly 3 triangle
neighbors.</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>To be sure,
I first triangulate the polymesh (to get rid of the strips) and then call
->BuildCells() and ->BuildLinks() on the mesh.</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>Then I
traverse trough the triangles of the mesh and check for each edge, if it has
exactly one other triangle that joins this edge.</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>For that, I
provide the current cell ID, the two point IDs of the current edge and the
list that is filled with the ID(s) of adjacent triangle
cells.</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>I am pretty
sure that the mesh that I am testing is closed. But just for the first
triangle, another adjacent triangle cannot be found.</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002></SPAN><SPAN class=140281216-07052002><FONT
face="Verdana Ref" size=2>Do I miss something? Do I have to preprocess the
polydata in some other way?</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref" size=2>Thank you
for any suggestions!</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2>Regards,</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2>Nils</FONT></SPAN></DIV>
<DIV><SPAN class=140281216-07052002><FONT face="Verdana Ref"
size=2></FONT></SPAN> </DIV>
<DIV><FONT face="Courier New" size=2>-------------------------</FONT><BR><FONT
face="Courier New" size=2>Nils Hanssen</FONT><FONT
face="Times New Roman"><BR></FONT><FONT face="Courier New" size=2>Surgical
Systems Laboratory</FONT><BR><FONT face="Courier New" size=2>research center c
ae sa r</FONT><FONT face="Times New Roman"><BR></FONT><FONT face="Courier New"
size=2>Friedensplatz 16</FONT><FONT face="Times New Roman"><BR></FONT><FONT
face="Courier New" size=2>53111 Bonn</FONT><FONT
face="Times New Roman"><BR></FONT><FONT face="Courier New" size=2>fon:
+49-228-9656-249</FONT><FONT face="Times New Roman"><BR></FONT><FONT
face="Courier New" size=2>fax: +49-228-9656-111</FONT><FONT
face="Times New Roman"><BR><U></U></FONT><U><FONT face="Courier New"
color=#0000ff size=2><A href="http://www.caesar.de/ssl"
target=_blank>http://www.caesar.de/ssl</A></FONT></U> </DIV><BR>
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