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VTK Gurus:<br>
<br>
I've got 3D models composed of triangular facets in vtkPolyData form. I
want to ensure that all of the polygon points are ordered in the
right-handed sense. I've tried the vtkPolyDataNormals filter. With the
debug flag turned on, I get messages that polygons have been
"reversed", but the polygons do not get updated i.e, reversed,
when I write to disk.<br>
<br>
This is the debug information from vtkPolyDataNormals for a simple cube
with 36 polygons. Just one of the polygons is left-handed:<br>
<br>
<font face="Courier, Courier" color="#0000FF">Debug: In
/usr/local/xti/vtk2.3/common/../graphics/vtkPolyDataNormals.h, line
102<br>
vtkPolyDataNormals (0x1011e888): vtkPolyDataNormals (0x1011e888): setting
FlipNormals to 1<br>
<br>
Debug: In /usr/local/xti/vtk2.3/common/../graphics/vtkPolyDataNormals.h,
line 93<br>
vtkPolyDataNormals (0x1011e888): vtkPolyDataNormals (0x1011e888): setting
Consistency to 1<br>
<br>
Debug: In vtkPolyDataFilter.cxx, line 48<br>
vtkPolyDataNormals (0x1011e888): setting Input to 0x1011b918<br>
<br>
Debug: In vtkPolyDataNormals.cxx, line 97<br>
vtkPolyDataNormals (0x1011e888): Generating surface normals<br>
<br>
Debug: In vtkPolyDataNormals.cxx, line 214<br>
vtkPolyDataNormals (0x1011e888): Reversed ordering of 1 polygons<br>
<br>
Debug: In vtkPolyDataNormals.cxx, line 273<br>
vtkPolyDataNormals (0x1011e888): Created 28 new points<br>
<br>
</font>My visualization app color codes the polygon, green on the front
and blue on the back. The one polygon still shows up blue after going
through my "clean up" code.<br>
<br>
Here is a snippet of my C++ "clean up" code. My data is in the
vtkPolyData object "pd":<br>
<br>
<font face="Courier, Courier" color="#0000FF"> vtkPolyDataNormals
*normals = vtkPolyDataNormals::New();<br>
normals->DebugOn();<br>
normals->FlipNormalsOn();<br>
normals->ConsistencyOn();<br>
normals->SetInput(pd);<br>
normals->Update();<br>
<br>
</font>All suggestions welcomed.<br>
<br>
Thanks,<br>
<br>
Scott<br>
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