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<DIV><FONT face=Arial size=2>Hi David</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I'm guessing you want to contour on elevation but
some datasets contain values for speed, energy, temperature etc at every point -
how else would users be able to contour these if it was not done through
scalars?</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>If you want to contour your z values you
can use a vtkElevationFilter to generate scalars from your dataset.
First you'll have to generate some structure though, at the moment you just
have a bunch of unconnected points. Try running your data through vtkDelaunay2D,
this will give you a dataset of connected triangles - then use the elevation
filter, then contour.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>If you search through the examples you'll find
cases of vtkElevationFilter, vtkDelaunay2D, vtkContourFilter.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>HTH</FONT></DIV>
<DIV><FONT face=Arial size=2>Malcolm</FONT></DIV>
<DIV> </DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=davidmichell@rediffmail.com
href="mailto:davidmichell@rediffmail.com">david michell</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> Tuesday, April 20, 2004 7:41
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [vtkusers] Contours and
scalars?</DIV>
<DIV><BR></DIV>
<P>Hi Everyone,<BR>I want to know why vtkContourFilter needs scalar
values?<BR>What role does the scalar values play in
contouring?<BR><BR>HELP!<BR>David Michell </P><BR><BR><A
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