[vtkusers] Tensors, VTK data storage, and superEllipsoids

[Ryan Dickie]

Hi,

I have a Diffusion Tensor MRI image currently spread across 6 vtk
files (1 for each of the 3 eigenvalues and 3 eigenvectors). My goal is
to be able to visualize this using superEllipsoids or superQuadrics.

My first question is how can I go about getting the data in the format
needed to use vtkTensorGlyph? Also, I am confused as to how to extract
a single vector from a vector field contained within one of the vtk
files described above. Is this information contained within a "cell"?

I wrote a program yesterday, to help learn vtk, where I created a
superEllipsoid, a parametric function source (with reasonably low
resolution), a mapper, and an actor manually. I Added aronud 125 of
those to be rendered. I was able to fully control all the color
parameters etc. I could then export it to a .wrl file and view it in
mayavi and others using the vtkVRMLExporter. This method is slow and
inefficient because I had to create several objects for each glyph and
supposedly execute all of those pipelines seperately but it was
reliable and fully customizable.

My second question is there a better way to visualize a whole series
of ellipsoids, and spheres, etc. without having the extra overhead as
described above?