Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!amdcad!ames!nrl-cmf!cmcl2!rutgers!iuvax!bsu-cs!cfchiesa
From: cfchiesa@bsu-cs.UUCP (Sir Xetwnk)
Newsgroups: comp.graphics
Subject: Re: Interactive Stereo Viewing
Message-ID: <1930@bsu-cs.UUCP>
Date: 23 Jan 88 05:08:18 GMT
References: <4615@tut.cis.ohio-state.edu> <146@rocky8.rockefeller.edu> <5039@well.UUCP>
Organization: CS Dept, Ball St U, Muncie, Indiana
Lines: 30
Summary: Stereo (3D) made simple

In article <5039@well.UUCP>, ewhac@well.UUCP (Leo 'Bols Ewhac' Schwab) writes:
> In article <1396@pixar.UUCP> flip@pixar.UUCP (Flip Philips) writes:
> >In article <4615@tut.cis.ohio-state.edu> WAMBOLD@OSU-20 (Sandra Wambold) writes:
> >>Does anyone on this BB know the proper translations and rotations for
> >>interactive stereo viewing?  [ ... ]

   [lots of stuff about rotation, matrices, focal length, etc. deleted]
> 
> 	Depending on camera seperation, you might be able to get away with
> simply shearing the projected image along the projected X axis rather than
> actually rotating it (after projection into the viewing frustrum (sp?)).
> Computationally, this is a real time-saver.
> 

I sent E-Mail to Sandra after reading her original posting, saying pretty much
this same thing, although perhaps not so efficiently.  Just "adding more and
more 'binocular disparity' (or 'shear') between the images, proportionate to
the 'Z' ('into the screen') coordinate" works fine for me.  I got the idea 
from my father (currently the Technical Consultant for the Stereo Division of
the Photographic Society of America), who has created many "manufactured" 
stereo images over the years by precisely this method -- albeit with physical
objects rather than computer images...

  Chris Chiesa
     a.k.a.
  Sir Xetwnk

  Senior, CS Dept.
  Ball State University
  Muncie, IN