[vtkusers] vtkVolume - Is there a way to use clipping planes on it?

Ramzy Darwish ramzy_d at hotmail.com
Wed Nov 17 18:52:31 EST 2004


Hello All,
I have been using VTK in school for a little more than a year now, and I am having some problems.

Don't worry, I am not asking anyone to do my homework.

I am doing an independent study continuing some work with medical volume rendering using the bruce gooch data set: http://www.cs.utah.edu/~bgooch/BruceBrain.html 


Now, the data file he gives out is a simple list of densities.
I was not allowed to use any vtkReaders, so I loaded the data in by hand, swapping byte-order and all that good stuff.

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.

This produced some nice (although not greatly useful) images, but I have always wanted to get the brain by itself.

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).

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.

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).

Can anyone point me in the direction of some more objects that I can use to interact with or modify vtkVolume objects?

Sorry this was so long, this is my first post here.

thanks,
ramzy
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.vtk.org/pipermail/vtkusers/attachments/20041117/3f969cf9/attachment.htm>


More information about the vtkusers mailing list