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<DIV><FONT face=Arial size=2>Hello,</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>
<DIV><FONT face=Arial size=2>I am using VTK 4.2 on Windows XP with VC++ 6.0 and
am relatively new to VTK. I am doing a project where I have to
register two 2.5 D scans (two surfaces) which are in wavefront obj format. I
have had no problems so far in terms of rendering or implementation of the
Iterative Closest Point Transform.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Now i need to implement a landmark detection
algorithm that needs the values of Gaussian and Mean curvatures at each point of
the surface. I have written the code using the VTK class vtkCurvatures and it
compiles and runs error free. I am able to get values for Gaussian curvature,
but for mean curvature i get the value zero at all points of the scan. Snippet
of my code is provided below, if anyone has faced this problem before or knows
what I am doing wrong, please please let me know.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Thanks in advance.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Regards,</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></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>/************************Code
Snippet***************/</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>//face 3 is a polydata object containing the
surface</FONT></DIV>
<DIV><FONT face=Arial
size=2>this->face3->DeepCopy(face2->GetOutput());<BR></DIV>
<DIV></FONT><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>//Get the Mean curvature and store in
vtkDoubleArray "mvals"</FONT></DIV>
<DIV><FONT face=Arial
size=2>this->curvm->SetInput(this->face3);
//curvm is an object of
vtkCurvatures<BR>this->curvm->SetCurvatureTypeToMean();<BR>this->curvm->Update();<BR>this->mvals->DeepCopy(curvm->GetOutput()->GetPointData()->GetScalars());<BR></FONT></DIV>
<DIV><FONT face=Arial size=2>//Get the Gaussian curvature and store in
vtkDoubleArray "gvals"</DIV></FONT>
<DIV><FONT face=Arial
size=2>this->curvg->SetInput(this->face3);
//curvg is an object of
vtkCurvatures<BR>this->curvg->SetCurvatureTypeToGaussian();<BR>this->curvg->Update();</FONT></DIV>
<DIV><FONT face=Arial
size=2>this->gvals->DeepCopy(curvg->GetOutput()->GetPointData()->GetScalars());</DIV></FONT></BODY></HTML>