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<P>Hi Sebastien,</P>
<P> If there is no way to do this in vtk (raycasting..?) there is an article in the C/C++ Users Journal that adresses this exact problem, to determine the triangle under a given x,y and then to interpolate z. "Triangular Tiling with Real-Time Searches" by J. David Wendel, November 1997. The source seems to be available: <A href="http://www.cuj.com/code/archive.htm">http://www.cuj.com/code/archive.htm</A><BR>but not the article, which would be more use, so how good is your library?!</P>
<P> Dave<BR></P></DIV>
<DIV></DIV>
<DIV></DIV>>From: "Sebastien_MARAUX" <MARAUX@ONDIM.FR>
<DIV></DIV>>To: "vtk mailing list" <VTKUSERS@PUBLIC.KITWARE.COM>
<DIV></DIV>>Subject: [vtkusers] vtkDataSet::findcell with different tolerances in x y z ?
<DIV></DIV>>Date: Wed, 29 May 2002 14:56:47 +0200
<DIV></DIV>>
<DIV></DIV>>Is there a method of type FindCell, but with different
<DIV></DIV>>tolerance in x, y and z ?
<DIV></DIV>>
<DIV></DIV>>This could help locate a cell of a MNT containing (x,y) by setting tolerance to (x,y=0, z=dblmax).
<DIV></DIV>>
<DIV></DIV>>And finally to find z altitude at x,y by using interpolation
<DIV></DIV>>methods of the cell.
<DIV></DIV>>
<DIV></DIV>>Note : Final goal is to find z for a given (x,y) couple of values in a group of cells making a (x,y) irregular surface.
<DIV></DIV>>
<DIV></DIV>>Sebastien MARAUX
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