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<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Hi,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>I have implemented a function for checking whether the
decimated image is rectangular or not. I call this function just after
decimation step and decimation is done using <b><span style='font-weight:bold'>vtkDecimationPro</span></b>.
Loosing any original corner and/or getting directly-not-connected two
consecutive vertices along image boundary signify non-rectangular shape. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Since no boundary edge can be shared by more than one
triangle, a boundary edge should occur only once in the facelist. <o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>But vtkDecimationPro sometimes produces some <b><span
style='font-weight:bold'>shared boundary edges</span></b>. While checking
thoroughly the triangles (a.k.a. facelist) generated through decimation (stored
into vtkPolyData) I have detected such cases. We have cross-verified that the
problematic triangle has non-zero area (if we consider all three co-ordinates).
<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>What could be the possible reasons for getting such cases?
Could you focus light on this issue?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Could you add <b><span style='font-weight:bold'>holes
detection technique</span></b> inside vtk library? We really need such function
to fix holes generated during decimation.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Thanks<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Verdana><span style='font-size:10.0pt;
font-family:Verdana'>Manoj<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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