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<DIV><FONT face=Arial size=2>Hi,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks Philip for the temporary class
vtkCurvatureTensor, I am currently trying to use that instead of the old class.
I am also trying to study your updated vtkCurvatures code that calculates
Principal Curvatures. I tried using the suggestion given to me by Joseph but it
yielded the same result, unfortunately.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>One observation i made was that, the results i
mentioned was what i got using VTK ver 4.2, i.e, zero value for mean curvature
at all points and for gaussian curvature they ranged from +5 to +50. On trying
VTK 4.4 without changing any code i got values ranging between -1 to +1 for both
mean and gaussian curvatures. I find that rather strange.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am not really well versed with the mathematics
and geometry related with curvatures since i am just trying to implement an
algorithm. But I thought i ought to let this fact be known to all. As far as the
data I am using is concerned, its a very well defined facial scan in wavefront
obj format with 59207 vertices and 117374 triangular faces.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>As pointed out by Philip, the bug mentioned by
Gorman and Mathieu shouldnt affect the mean calculation in the case of the old
vtkCurvatures class as vtkExtractTensorComponents isn't called at
all.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Anyhow I hope one of Philip's updated classes works
for my task, and I am eagerly waiting for the final updated absract curvature
class for my future work.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Cheers,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Prathap Nair<BR>Dept of Electronic
Engineering,<BR>Queen Mary, University of London,<BR>Mile End Road, London E1
4NS (UK).</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=jnsasi@hotmail.com href="mailto:jnsasi@hotmail.com">José Nsasi B.</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=vtkusers@vtk.org
href="mailto:vtkusers@vtk.org">vtkusers@vtk.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, July 06, 2005 3:24
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [vtkusers] Re: Mean
curvature</DIV>
<DIV><BR></DIV>
<DIV>
<P>Hi;</P>
<P>The mean curvature works very well and its estimation looks better than
gauss curvature.</P>
<P>Try to use:</P>
<P> this->curvm->SetCurvatureType(1);//this->curvm->SetCurvatureTypeToMean();</P>
<P>mvals=this->curvm->GetOutput()->GetPointData()->GetScalars();<BR><BR>Best
Regards</P><BR><BR><BR>
<DIV>-------------------------------------------------------------- <BR><FONT
size=4><STRONG><FONT face="Garamond, Times, Serif"><EM>Joseph Nsasi Bakambu,
</EM></FONT></STRONG></FONT></DIV></DIV>
<P>
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