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<DIV><FONT face=Verdana><FONT size=2>When apply vtkFeatureEdges to a dataset
that has been processed by vtkPolyDataNormals or others, then
the</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2>result seems not
expected:</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2></FONT></FONT> </DIV>
<DIV><FONT face=Verdana><FONT size=2>vtkPolyData *pointset=</FONT><FONT
size=2>myFunctionCreatePointSet();</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2></FONT></FONT> </DIV>
<DIV><FONT face=Verdana><FONT size=2>vtkDelaunay2D
*del=vtkDelaunay2D::New();</FONT></FONT></DIV>
<DIV><FONT face=Verdana><FONT
size=2>del->SetInput(pointset);</FONT></FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><FONT face=Verdana><FONT size=2>vtkPolyDataNormals
*nrms=vtkPolyDataNormals::New();</FONT></FONT></DIV>
<DIV><FONT face=Verdana
size=2>nrms->SetInputConnect(del->GetOutputPort());</FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><FONT face=Verdana size=2>vtkSmoothPolyDataFilter
*sf=vtkSmoothPolyDataFilter::New();</FONT></DIV>
<DIV><FONT face=Verdana
size=2>sf->SetInputConnect(nrms->GetOutputPort());</FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><FONT face=Verdana size=2>/* Here, only input connected to del when results
is correct.</FONT></DIV>
<DIV><FONT face=Verdana size=2> because when display tb, many
edges it not "BoundaryEdges".</FONT></DIV>
<DIV><FONT face=Verdana size=2> that is vtkPolyDataNormals or
vtkSmoothPolyDataFilter has changed</FONT></DIV>
<DIV><FONT face=Verdana size=2> the topology of Delaunay mesh.
So how to avoid this problem?</FONT></DIV>
<DIV><FONT face=Verdana size=2> I only want to get
BoundaryEdges, just using del as input?</FONT></DIV>
<DIV><FONT face=Verdana size=2>*/</FONT></DIV>
<DIV><FONT face=Verdana size=2>vtkFeatureEdges
*fe=vtkFeatureEdges::New();</FONT></DIV>
<DIV><FONT face=Verdana
size=2>fe->SetInputConnect(sf->GetOutputPort());</FONT></DIV>
<DIV><FONT face=Verdana
size=2>fe->BoundaryEdgesOn();<BR>fe->FeatureEdgesOff();<BR>fe->ManifoldEdgesOff();<BR>fe->NonManifoldEdgesOff();<BR>fe->ColoringOff();</FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><FONT face=Verdana size=2>vtkTubeFilter
*tb=vtkTubeFilter::New();</FONT></DIV>
<DIV><FONT face=Verdana
size=2>tb->SetInputConnect(fe->GetOutputPort());</FONT></DIV>
<DIV><FONT face=Verdana size=2>tb->SetRadius(0.5);</FONT></DIV>
<DIV><FONT face=Verdana size=2>tb->SetNumberOfSides(6);</FONT></DIV>
<DIV><FONT face=Verdana size=2></FONT> </DIV>
<DIV><FONT face=Verdana size=2>// mapper tb and display...</FONT></DIV>
<DIV><FONT face=Verdana size=2>... ...</FONT></DIV>
<DIV><FONT face=Verdana><FONT size=2></FONT></FONT> </DIV>
<DIV><FONT face=Verdana><FONT size=2> </DIV>
<DIV>
<HR style="WIDTH: 122px; HEIGHT: 2px" SIZE=2>
</DIV></FONT>
<DIV><FONT color=#c0c0c0><FONT size=2><SPAN>lab_zj</SPAN></FONT></DIV>
<DIV><FONT size=2>2009-01-15</FONT></FONT></DIV></FONT></BODY></HTML>