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<DIV><FONT face=Arial size=2>Hello All,</FONT></DIV>
<DIV><FONT face=Arial size=2>I have been using VTK in school for a little more
than a year now, and I am having some problems.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Don't worry, I am not asking anyone to do my
homework.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I am doing an independent study continuing some
work with medical volume rendering using the bruce gooch data set: <A
href="http://www.cs.utah.edu/~bgooch/BruceBrain.html">http://www.cs.utah.edu/~bgooch/BruceBrain.html</A>
</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Now, the data file he gives out is a simple list of
densities.</FONT></DIV>
<DIV><FONT face=Arial size=2>I was not allowed to use any vtkReaders, so I
loaded the data in by hand, swapping byte-order and all that good
stuff.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So I got a rendering of the head, but because I had
no other information other than density, I was only able to somewhat get the
brain isolated was by using the vtkVolume object with texture
mapping.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>This produced some nice (although not greatly
useful) images, but I have always wanted to get the brain by
itself.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I tried using the vtkContourFilter, which didn't
seem to want to work right. Instead of leaving values all through the head in my
ranges, it left sections of the entire head (i.e. I would get from the neck/chin
to the nose instead of the whole head with only say, the skin
removed).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>I tried using a combination of vtkClipPolyData with
scalar values and implicit planes, but this didn't work because after cutting,
the resulting geometry would be full of holes. I think I was using it
wrong.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So I went back to the drawing board and I have
decided to look at the densities in the file and ignore those outside of the
brain wherever possible. So now I have a range of values within to use, but I
still have some extraneous (sp) pieces laying about that I might be able to
remove, but I can't figure out how. Is there a way to remove chunks out of a
volume? Not by scalar though. I could use a sphere or other builtin implicit
function if necessary, but it seems that the other methods of doing stuff like
this are not set up to work with vtkVolume's (as they are derived from
vtkProp).</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Can anyone point me in the direction of some more
objects that I can use to interact with or modify vtkVolume
objects?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Sorry this was so long, this is my first post
here.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>thanks,</FONT></DIV>
<DIV><FONT face=Arial size=2>ramzy</FONT></DIV></BODY></HTML>