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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 size=2> I am trying to get the gradient
vectors of all the vertices of triangle surface mesh. One of my friend gave me
some advice list as below:</FONT></DIV>
<DIV><FONT face=Arial size=2><FONT face=Arial size=2></FONT></FONT> </DIV>
<DIV><FONT face=Arial
size=2>*************************************************************************************************</FONT></DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman"
size=3>Triangle meshes are piece-wise linear approximation of smooth manifold.<BR>the so-called gradient is not well-defined. you can use any reasonable<BR>approximation from the gradient (normal) of the incident faces.</FONT><BR>**************************************************************************************************</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2> Can I just simply use to vtkPolydataNormals
to get all the normal vectors? Then how can I relate the normal vectors with the
gradient vectors at the points?</DIV></FONT>
<DIV><FONT face=Arial size=2> </DIV></FONT>
<DIV><FONT face=Arial size=2>Best
Wishes,<BR>-----------------------------------------------------------------<BR>Dongqing
Chen<BR>Ph.D Research Assistant<BR>Rm. 07, Paul C. Lutz Hall<BR>Computer Vision
& Image Processing (CVIP) Lab<BR>Department of Electrical & Computer
Engineering<BR>Speed School of 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:+1-502-852-2789
(Lab)<BR>
+1-502-852-6130
(Office)<BR>-----------------------------------------------------------------</FONT></DIV></BODY></HTML>