Hi Mark,

thanks for your remarks, but i do not completely agree with you. At least compared 
with the things i experience with my settings.

> 
> > but the eyes look parallel into the scene. how can i focus them on a
> > specified point?
> 
> It sounds like you might be confused about the eye basis vectors and
> stereo convergence.  The eye coordinate systems are defined to align
> with the canvas/imageplate/screen, so +Z in eye coordinates is always
> aligned with +Z in screen coordinates.  With the default 
> window eyepoint
> policy, the eyes will be centered in the canvas in Y, with 
> the X offsets
> equal to the interpupilary distances in the PhysicalBody (Z 
> displacement
> is determined by the field of view).
> 
> With a perspective view, each eye is at the apex of a skewed, 
> truncated
> viewing frustum that defines the projection.  The rays extending from
> each eye to the canvas corners define the sides of the frustum and the
> near and far clip planes are the truncated planes of the frustum.  The
> center axes of these frustums converge to the center of the canvas and
> you could think of them as the nominal view vectors for each eye.
> 

agree so far

> So the orientations of the eyes don't matter, just their positions
> relative to the canvas.  Your real eyes will converge and diverge
> depending upon the depth in the rendered image to which you wish to
> focus (although some people have trouble doing this since it requires
> decoupling the focal length of the lens of each eye from the stereo
> disparity between them; keeping objects near the plane of the screen
> helps).
> 

i don't see that quite. why should people do something like this when having shutter 
glasses. i think the program has to set the focus (emulate the focus on a ceratin 
object). nobody has to force their eyes to see a stereo effect.
i would argue that each eye has to have its own projection matrix and thus its own 
frustrum to experience a real 3D stereo effect.

i mean if you compare the standard stereo to that one compatibility mode gave me i 
have the evidence. before i had a slight impression that my object is in front or 
inside of screen. but i had no sensation of depth in the object itself. in fact the 
direction the eyes where looking didn't converge at all. it was like staring into the 
infite distance.

minor note: i once tried default stereo with the DirectX implementation on Win98 and 
it was really nice (just as i get now with open gl) and simply worked from scratch.
perhaps there is a minor difference between these two that may also be driver 
dependent.

moreove we where trying our application on autosteroscopic 3D panel with the same 
effect.

> You might encounter problems with the stereo convergence 
> being too wide
> or narrow.  This means that the model in the virtual world is 
> scaled too
> large or small, or that it is too close or far away from the 
> eyes.  It's
> preferable to adjust the scale of the virtual world through a 
> transform
> or through an explicit screen scale factor and move the view platform
> appropriately, so that the eye separation in the PhysicalBody can be
> meaningfully calibrated for individual users, but some 
> programmers just
> adjust the eye separation in the PhysicalBody directly to solve the
> problem.

?you suggest that the objects in my scene scale in respect to the distance to the 
viewer?

> 
> > related to this i found the problem that picking doesn't 
> work correctly in
> > compatibility mode. am i missing a setting or is there 
> definitly no (known)
> > solution/workaround?
> 
> Picking is one of the things that requires the normal Java 3D 
> view model
> to work correctly.  No workaround is available.

and that is pretty sad... 

by the way this is bug
4790016 - PickObject generatePickRay return wrong PickShape if View compatibility 
enable

i already tried to work around by defining my own pick shape, but without any effect


thanks for your help,
perhaps we can dig into this problem toghether once and forever.

Karsten

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