[vtkusers] clip one vtkPolyData with another?

[Alle Meije Wink]

Hi,

I am trying to combine showing the outer surface of an MRI brain (iso
surface) with 3 planes that define a cut inside the brain (say the upper
back right part has been cut out.

Defining the surface (with vtkMarchingCubes) was not a problem. the
cutout (with vtkPlanes and vtkClipPolyData) went fine as well.

Then I drew the cut planes with vtkCutter (using the same planes as I
did for clipping). The cutplanes first extended to the edge of the
bounding box, obscuring most of the brain surface. I (sort of) solved
this by putting another vtkClipPolyData after the vtkCutter, which
removes the part of the cut plane outside the brain.

The cut after thresholding is very rough, though. Does anyone know
whether it is possible to clip a vtkPolyData with *another* vtkPolyData?
The (visually) best result would be to limit the cutplanes by the brain
surface. I tried to use vtkClipPolyData, but this can only use a
vtkImplicitFunction to clip, and not another vtkPolyData.

Is there a way to compute the intersection of two vtkPolyData
structures? Or to convert a vtkPolyData into a vtkImplicitFunction?
Perhaps this can be done in another, very elegant way???

Many thanks,
Alle Meije Wink

-- 

  Brain Mapping Unit
  Dept. of Psychiatry
  University of Cambridge
  Downing Site
  Cambridge CB2 3EB

  tel: (+44) (0)1223 764676
  fax: (+44) (0)1223 336581

  alle_meije at yahoo.co.uk


		
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