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<DIV><FONT face=宋体 size=2>Hi all,</FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2> (0) Before process:</FONT></DIV>
<DIV><FONT face=宋体 size=2> I have
a polydata with vtkPoints (x,y) z is a <FONT
color=#800000><STRONG>constant</STRONG></FONT> data (for example
100).</FONT></DIV>
<DIV><FONT face=宋体 size=2> I have a
vtkfloatarray with the <FONT color=#800000>same</FONT> size of
vtkPoints</FONT></DIV>
<DIV><FONT face=宋体 size=2> My
purpose: <STRONG>to draw a contour according vtkfloatarray value at the
level of
z(const) </STRONG></FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2> 1) first data
set </FONT></DIV>
<DIV><FONT face=宋体
size=2> I assigned the
vtkfloatarray value to z </FONT></DIV>
<DIV><FONT face=宋体 size=2> so I have the
polydata a set of <STRONG><U>virtual(or fake)</U></STRONG> vtkpoints
(x,y,z) (z = value of vtkfloatarray) </FONT></DIV>
<DIV><FONT face=宋体 size=2> Then I
use</FONT><FONT face=宋体 size=2> <FONT
color=#0000ff><STRONG>vtkSurfaceReconstructionFilter</STRONG></FONT>,
<STRONG><FONT color=#0000ff>vtkContourFilter</FONT></STRONG>,</FONT></DIV>
<DIV><FONT face=宋体
size=2> finally I got a <FONT
color=#008000 size=3><STRONG>isosurface image</STRONG></FONT>.</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=宋体 size=2> 2) second data set</FONT></DIV>
<DIV><FONT face=宋体 size=2> I still let
z =(const like 100)</FONT></DIV>
<DIV><FONT face=宋体
size=2> Then</FONT><FONT face=宋体
size=2>
polydata->GetPointData()->SetScalars(vtkfloatarray)</FONT></DIV>
<DIV><FONT face=宋体 size=2> so I have
the polydata with a set of vtkpoints(x,y, 100) with scalars.</FONT></DIV>
<DIV><FONT face=宋体 size=2> use <FONT
color=#0000ff><STRONG>vtkDelaunay2D</STRONG></FONT> , <FONT
color=#0000ff><STRONG>vtkContourFilter</STRONG></FONT>,</FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体
size=2> Finally I got
<STRONG><FONT color=#ff0000 size=4>nothing</FONT></STRONG>. </FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2> Actually I want to draw a
contour according to the scalar value ,</FONT></DIV>
<DIV><FONT face=宋体 size=2> not to draw a contour
according to z value.</FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2> I am just curious that,
for the same data filter: contour,</FONT></DIV>
<DIV><FONT face=宋体 size=2> why sometimes <FONT
color=#0000ff><STRONG><FONT size=3>VTK</FONT></STRONG> </FONT>draws the image
according to Z value , sometimes</FONT></DIV>
<DIV><FONT face=宋体 size=2> <STRONG><FONT color=#0000ff
size=3>VTK</FONT></STRONG> draws the image according to scalar
value.</FONT></DIV>
<DIV><FONT face=宋体 size=2> </FONT></DIV>
<DIV><FONT face=宋体 size=2> Any of your
response is appreciated ! </FONT></DIV>
<DIV><FONT face=宋体 size=2></FONT> </DIV>
<DIV><FONT face=宋体 size=2>Qin</FONT></DIV></BODY></HTML>