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<DIV><FONT face="Bookman Old Style">Hi,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">If you want to visualize color slices, you
need to </FONT></DIV>
<DIV><FONT face="Bookman Old Style">1. read these slices. You need to put the
SetDataExtent(0, 111, 0, 127, 1, 300);<BR>before Update();</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style"> vtkTIFFReader *v16 =
vtkTIFFReader::New();<BR></FONT><FONT
face="Bookman Old Style"> v16->SetFilePrefix("D:\\MyVC\\VTKtest\\Raycasting\\Data\\BrainColor\\brain");<BR> v16->SetFilePattern("%s%d.TIF");<BR> v16->SetDataExtent(0,
111, 0, 127, 1,
300);<BR> v16->SetDataSpacing(1.2,1.2,0.5);<BR> v16->SetDataOrigin(0.0,
0.0, 0.0);</FONT></DIV>
<DIV><FONT
face="Bookman Old Style"> v16->SetNumberOfScalarComponents(3);<BR></FONT><FONT
face="Bookman Old Style"> v16->Update();</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">2. Add the 4th component. The first three
components are color and the 4th is used to map to opacity. I compute the
luminancy according to the firft three components and take it as the 4th
component.</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">3. Opacity map using
vtkPiecewiseFunction</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">4. no need color map function</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">5. you need vtk5.0</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Regads,</FONT></DIV>
<DIV><FONT face="Bookman Old Style"></FONT> </DIV>
<DIV><FONT face="Bookman Old Style">Yixun Liu</DIV>
<DIV><BR></DIV></FONT>
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