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<DIV><FONT face=Arial size=2>Dear All:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2> Now I am trying to obtain the
gradient vector at each vertice of 3D polygonal data. I fidn that the
</FONT><FONT size=3>vtkFiniteDifferenceGradientEstimator takes takes a scalar
input of <A class=el
href="http://www.vtk.org/doc/release/4.2/html/classvtkImageData.html"><FONT
color=#000000>vtkImageData</FONT></A>. Does anyone have any hint on how to
compute the gradient vector of 3D polygonal data?</FONT></FONT></DIV>
<DIV><FONT face=Arial> </FONT></DIV>
<DIV><FONT face=Arial><FONT size=2> Thanks a
lot.</FONT></FONT></DIV>
<DIV><FONT face=Arial><FONT size=2></FONT></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2>Best Wishes,</FONT></FONT></DIV>
<DIV><FONT face=Arial> </DIV></FONT>
<DIV><FONT face=Arial size=2>Dongqing Chen<BR>Rm. 007, Paul C. Lutz Hall
<BR>Computer Vision & Image Processing (CVIP) Lab<BR>Dept. of Electrical
& Computer Engineering<BR>University of Louisville<BR>Louisville, KY.
40292<BR>U.S.A.<BR>Email: <A
href="mailto:dqchen@cvip.louisville.edu">dqchen@cvip.louisville.edu</A><BR>Phone:
(502)852-6130(Office)<BR>
(502)852-2789(Lab)</FONT></DIV></BODY></HTML>