Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!wasatch!sunset.utah.edu!u-jmolse
From: u-jmolse%sunset.utah.edu@wasatch.UUCP (John M. Olsen)
Newsgroups: comp.graphics
Subject: Re: 3-D perceptual abilities
Message-ID: <1247@wasatch.UUCP>
Date: 7 Mar 89 18:14:37 GMT
References: <207400002@s.cs.uiuc.edu>
Sender: news@wasatch.UUCP
Reply-To: u-jmolse%sunset.utah.edu.UUCP@wasatch.UUCP (John M. Olsen)
Organization: University of Utah, Computer Science Dept.
Lines: 35

In article <207400002@s.cs.uiuc.edu> carroll@s.cs.uiuc.edu writes:
>RE: 3-D from repeating 2-D patterns
>I first noticed this staring up at the roof of a dodge van, with a regular
>patterns of holes in it. I've since learned how to do it on demand, even
>on a keyboard (so it looks like the keys have ``stretched'' up toward me).
>Look straight down at the G H keys, and let your eyes go unfocused and
>somewhat crossed.

>Alan M. Carroll          "And then you say,
>carroll@s.cs.uiuc.edu     We have the Moon, so now the Stars..."  - YES
>CS Grad / U of Ill @ Urbana    ...{ucbvax,pur-ee,convex}!s.cs.uiuc.edu!carroll

Okay, all you cross-eyed folks.  Read this:

12345678901245q678912l45q78t912l45q7t9z12l457t*9z12l45t*9z1T2l45t*9z1Tl45t*$9
qwertyui5nqwrtayui5qwxrtayui5qwxrayui5qwxzrauiC5qwxzraiCt5qwxzaiCt57qwza>iCt5
asdfghjkl;asfghjkl;aszfghklr;aszfghkr;yaszfgkr;yaszgfgr;ya.szggrT;ya.sggrT);y
zxcvbnm,./zxvb1nm,.zxyvb1m,>.zxyvb1m>.-zxyvbm>T.-xyPvb>TG.-xyPb>pTG.-xPbT>pTG
12345678901245r678912745r78B912745r7B9t127457By9t27Y45By9t2N7Y5Bry9t2NY5Bry*9
^         ^
This is the repeat frequency.  (Sorry for the ugly font.)

Cross-eyed, the text is recessed.  Going diverged makes the text poke out.
This technique *might* show up in a not-too-distant future Scientific 
American if Mr. Dewdney things there are enough bug-eyed readers. :^)
Imagine having stereoscopic wallpaper where only you can see what's there.

The answer: ( quit now if you want to figure it out yourself :^)

Hi thErE.

/\/\ /|  |    /||| /\|       | John M. Olsen, 1547 Jamestown Drive  /\/\
\/\/ \|()|\|\_ |||.\/|/)@|\_ | Salt Lake City, UT  84121-2051       \/\/
/\/\  |  u-jmolse%ug@cs.utah.edu or ...!utah-cs!utah-ug!u-jmolse    /\/\
\/\/             "A full mailbox is a happy mailbox"                \/\/