[vtkusers] hardware stereo swapped LR images in raycast, but not 2D texture in volume rendering

[Dr. Daniel James White PhD]

Hi ,

I am experiencing a strange stereo problem using VTK with the mayavi 
frontend,
concerning display of hardware stereo using a crystaleyes glasses system
on a redhat linux 8.0 box with ATI radeon 7500, and the Xig.com Xserver 
for quad buffered stereo.

When I load in the IronProtein.vtk example file
and use the new Mayavi module
volume
by Gerard Gorman (see mayavi list recently)

then turn on the
SetStereoTypetoCrystalEyes
and
StereoRenderOn
in the
Configure vtkXOpenGLRenderWindow
dialog box

Now when I rotate the data set , I think the faster 
vtkVolumeTextureMapper2D is used.
In hardware stereo this looks correct (but it is fuzzy so a bit hard to 
tell)

however, when the rotation is finished the slower
vtkVolumeRayCastMapper is used for a nice rendered image.
When rendering is finished the left and right images are displayed 
incorrectly!
What the dialog boxes think is the right image is actually the left 
image, and vice versa.

This behavior is also seen with a python script I cobbled together to 
display stacks of tiff images
using ivtk from mayavi.

Is the problem a bug in the vtkVolumeTextureMapper2D or somewhere 
upstream?

Hardware stereo functions correctly in other software such as pymol and 
bodil.

Previously I have applied a little hack to mayavi to enable stereo 
viewing as suggested by
Prabhu Ramachandran.

also SetStereoTypeToLeft gives the same incorrect/swapped double image 
as SetStereoTypetoCrystalEyes.
but SetStereoTypeToRight only displays 1 image to both eyes.

When StereoRenderOn is turned off, or not turned on, same thing,
only the right eye sees and image, and the screen is blank to the left 
eye, casing a flickering, or half intensity image.

I don't know if the hack to mayavi  has caused this problem?
I don't think the flickering happened before I applied the hack.

any ideas VTK stereo folks?

cheers

Dan


Dr. Daniel James White BSc. (Hons.) PhD
Cell Biology
Department of biological and environmental science
PO Box  35
University of Jyväskylä
Jyväskylä FIN 40014
Finland
+358 (0)14 260 4183 (work)
+358 (0)414740463 (mob)

http://www.chalkie.org.uk
dan at chalkie.org.uk
white at cc.jyu.fi