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<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Hi, I have just implemented a passive stereo effect in
C++ with VTK libraries using the <i><span style='font-style:italic'>CrystalEyes</span></i>
method on a NVidia Quadro Graphics Card, with two projectors, a
not-depolarizing screen and linear polarized lens and glasses. This is the
code:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color="#333399"
face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial;
color:#333399'>renWin->SetStereoCapableWindow(3);<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color="#333399"
face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial;
color:#333399'>renWin->StereoRenderOn();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color="#333399" face=Arial><span
style='font-size:10.0pt;font-family:Arial;color:#333399'>renWin->SetStereoTypeToCrystalEyes();<o:p></o:p></span></font></p>
<p class=MsoNormal style='text-autospace:none'><font size=2 color="#333399"
face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial;
color:#333399'>renderer->GetActiveCamera()->ParallelProjectionOff();<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color="#333399" face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:#333399'>renderer->GetActiveCamera()->SetEyeAngle(3.0);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color="#333399" face=Arial><span lang=EN-GB
style='font-size:10.0pt;font-family:Arial;color:#333399'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>The stereo effect is perfect if the object is
generated (from DICOM images) with a <i><span style='font-style:italic'>Surface
rendering</span></i>, whilst with the <i><span style='font-style:italic'>Volume
Rendering</span></i> the 3D image generated is confused.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>The strange thing is that if I set a negative “eye
angle” the stereo effect on the Volume Rendering is good but reversed (I see
the reconstructed object beyond the plane of the screen).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Using the surface rendering, instead, the effect is
perfect in both directions (but I’m interested that the object poke
through the plane of the screen).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I’m thinking the problem could be the way the <i><span
style='font-style:italic'>ray casting</span></i> method is implemented in the Volume
rendering: probably the camera and the viewpoint are not in the same point.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>I think this also because using a <font
color="#333399"><span style='color:#333399'>SetEyeAngle(0.3</span></font>) on
the Volume Rendered image gives me roughly</span></font><font size=2
face=Tahoma><span lang=EN-GB style='font-size:10.0pt;font-family:Tahoma'> </span></font><font
size=2 face=Arial><span lang=EN-GB style='font-size:10.0pt;font-family:Arial'>the
same effect of a <font color="#333399"><span style='color:#333399'>SetEyeAngle(3.0)</span></font>
on the Surface Rendered object, therefore I think the images for left and right
view are generated, with the Volume Rendering, in a different way in comparison
with the Surface Rendering ones.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Someone could help me to address my problem?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Thanx,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>Valeria<o:p></o:p></span></font></p>
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