Volume rendering + transformation + perspective = artifacts.

Volume rendering + transformation + perspective = artifacts.

Post by Tomas Lundbe » Tue, 02 Jul 2002 18:39:27



I am using TGS Open Inventor 3.0 along with Volume Rendering 2.1 to
visualize medical volume data. I use 3D-texturing with view-aligned
slices.

Everything seems to work just fine until I do either a translation or
more than one rotation of the volume. Even if I multiply two rotations
into one before applying I get the problem.

The problem is that when I view  my volume (by rotating it with  mouse
input in my examiner viewer) it seems to become strangely "sliced"
into small cubes and opaque planes occur in seemingly random places.
Also sections of the volume disappears occasionally. This problem only
occurs in perspective mode. When using an orthographic camera
everything looks fine.

Has anyone seen this problem before? Why can't I translate or do
multiple rotations to my volume when I watch it in perspective mode?

Any comments are gratefully accepted.
Thanks.

/Tomas

 
 
 

1. volume rendering + transformation + perspective = artifacts

I am using TGS Open Inventor 3.0 along with Volume Rendering 2.1 to
visualize medical volume data. I use 3D-texturing with view-aligned
slices.

Everything seems to work just fine until I do either a translation or
more than one rotation of the volume. Even if I multiply two rotations
into one before applying I get the problem.

The problem is that when I view  my volume (by rotating it with  mouse
input) it seems to become strangely "sliced" into small cubes and opaque
planes occur in seemingly random places. Also sections of the volume
disappears occasionally. This problem only occurs in perspective mode.
When using an orthographic camera everything looks fine.

Has anyone seen this problem before? Why can't I translate or do
multiple rotations to my volume when I watch it in perspective mode?

Any comments are gratefully accepted.
Thanks.

/Tomas

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