From: brucec@phoebus.labs.tek.com (Bruce Cohen)
Subject: Re: SCI: How many dimensions does V.R. have?
Date: 28 Apr 92 18:23:41 GMT
Organization: Software Technology Research Laboratory, Tektronix Inc.



In article <1992Apr28.075146.2841@u.washington.edu> gay@mr4dec.enet.dec.com writes:
> ...
>
> So, in summary, the number of dimensions is limited to three (plus time) 
> for display but can be much higher for maneuvering.  The cost will be in
> design time to prevent user confusion.
> 

There are ways to display more dimensions: use color, sound, and other
sensory modes as well.  Color allows 3 additional dimensions; one useful
way to distinguish them is as hue, brightness, and saturation (chroma).
Sound allows at least three dimensions: loudness, pitch, and timbre,
though timbre can be used as more than one dimension.  You can use
structures based on these raw dimensions to add still more dimensions,
e.g. visual texture.  All of these techniques have been used to encode
data for visualization of data sets with more than four dimensions
(though I've never heard of anyone trying them all at once).

The big problem with all this is of course navigating through all this
complexity.  Few people have an intuitive feel for navigating through
high-dimension space.  The good news is that with well-designed input
systems to control the viewpoint trajectory a lot of the cognitive load
can be relegated to kinesthetic processing: "muscle thinking."  That's
where the advanced input technologies like gloves fit in.
--
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"The end cause ... is too often handed off as an afterthought to harried
interface designers who follow programmers around with virtual brooms
and pails." - Brenda Laurel in "Computers as Theatre"
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Speaker-to-managers, aka
Bruce Cohen, Software Technology Research Lab   email: brucec@strl.labs.tek.com
Tektronix Laboratories, Tektronix, Inc.         phone: (503)627-5241
M/S 50-662, P.O. Box 500, Beaverton, OR  97077