[vtkusers] vtkTensorGlyph display question

[Patrick (Peng) Cheng]

hi vtkusers,
I have a volume tensor data, and I use an vtkExtractVOI to get an slice of the image,
pass this slice and a sphere source to the vtkTensorGlyph. then I got ellipse shown on the screen.

but the question is when I tried to rotate the scene and change view angle.
the whole scene just black out, I can even see all the other actors.
What might be the problem?

Also I only need to draw the Glyphs on the valid image data not the background. How do I filter out the backgound points from the image data.
I tried the vtkImageTreshold filter. but it seems that it doesn't work, coz it does not actually delete the background points from the StructuredPoints.


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Peng (Patrick) Cheng
Biomedical Engineering
University of Iowa
Tel:(319) 400-7442
Email: peng-cheng at uiowa.edu