From: Randy Gardner <randyg@slip.net>
Newsgroups: alt.ascii-art
Subject: Stereogram FAQ
Date: Mon, 17 Nov 1997 23:57:46 -0800




I guess I would be considered a 3D expert, so I will start filling
in everybodys blanks on stereograms.


news:alt.3d.sirds is the NG for discussing them, but I am
currently the _only_ reader, so you will just get me when you
post.  I have made several attempts to revive the newsgroup,
but with no luck.  The spam level there is off the scale,
which also really discourages people from posting.




How-To-View them:
Well, I can't really fill in here, since I have always been VERY 
good at seeing them.  I just look at them, and I can see them
in around one and a half seconds, which I am told is VERY rare.
(I also have better then 20/20 vision, but that's another point)
Most people report 30sec-1min to see an image.


Methods of viewing:
I'm regurgitating what I have heard, I've never done any of it.

1. Some people say holding it in front of a mirror helps, but this
   requires printing it.

2. Pretend to be stareing through your monitor, at an imaginary
   object behind of it.

3. Put your nose up to the monitor, and slowly pull back.

4. Go read one of the many other viewing FAQs.



Technical stuff:

The brain does stereo corrolation constantley, useing the left
and right images, to compute a 3d map, which your brain does
perfectley in real time.  Normaly the brain gets two images,
seperated by a couple of inches, and goes on from there.
3D reb/blue images are just two images, one in the red chanel,
and one in the blue/green chanels, which the glasses seperate
into the two images, and feed them to the eyes.  The 3d glasses
that use LCD shutters do the same thing, in the way it gives two
seperate images to the eyes, but it does it by switching the left
and the right image on the display very quickley, and the glasses
change which eye the image goes to by useing LCD panels to
select which eye the image currently being displayed goes to.
The expensive VR helmets that make everything real 3D do the
same thing, useing two displays to send two images to the brain.
If you notice, all these methods work on the same pricipal, getting
a differnt image to each eye.  All of them send a different image
to each eye. Even the red/blue image, which looks like one image,
but it is actually two, and the glasses seperate them out and
give the correct images to each eye.  But what about stereograms????

Stereograms, AKA SIRDS (Single Image Random Dot Stereograms), SIS
(Single Image Stereograms), SIDS (Single Image Dot Stereograms)
only have one image.  But that image is TWO, like all the others.
First, to get an idea of what the two images are, and what they
do.  Do this:  1. Close one eye.  2. Hold your finger about
one foot (.3m) from your face.  Look at your monitor.  Switch
eyes.  Keep switching them every second or so.  part2: Open both
eyes. look at your monitor.  See how it looks like you have TWO
fingers?  While looking at the monitor, slide your hand closer
and further away from you.  See how the difference inbetween
the two finges gets closer and further apart?  When looking
normaly, your brain computes the difference inbetween the images
from your left and right eyes, and uses it to find the distance.
If you look at a red/blue 3D image, you will see that the closer
objects have more seperation inbetween the red and the blue lines.
This is the whole basis of 3D corleation.  Do the part2 execrise,
but look at the moveing finger instead of the monitor.  See how
it looks like you have two sliding monitors, that is information
the brain also has to compute, since your eyes can point, and
stereo comera images look stright ahead.  You saw how the difference
inbetween the fingers was proportional the the distance.  In 
stereograms as well as all the other methods, you change the distance
of an object by moveing the two images of it further of less apart.
Look here:
: >                 O                  O
: >                O      ,          O      ,
: >                O    .:/         O     .:/
: >                  ,,///;,  ,/       ,,///;,  ,//
: >                 o::33333://       o:33333::///
: >                >::3333333\\      >:3333333:\\\
: >                  ''\\\\\" '\       ''\\\\\"  '\
: >                     ';\    '\         ';\     '\
: >
See how different parts of the images are shifted slightley?  
(bubbles, tail, etc...)  This is the same thing.  By changing
the difference inbetween the parts of the images, you change
the depth.  Now, what's unique to stereograms: 1. Why do you
have to shift your eyes?  To get the TWO images that's required
for all 3d.  Look here:
               -o           -o            
               -o            -o           
               -o             -o          
               -o            -o           
               -o           -o            
               -o            -o           
               -o             -o          
               -o            -o           
               -o           -o            
Total, it's one image.  But it needs to be TWO!  Normally,
your eyes focus on the screen of the monitor.  Remember how
there was TWO fingers when you looked at the monitor with
your finger halfway?  If you put two fingers up, and slide 
them closer are further from you while looking at the monitor,
at some distance you would see THREE fingers.  Now, imagine
the image above was drawn on a peice of glass.  If you held
the peice of glass inbetween you and the monitor, and the
correct distance, the two images would become 3 and be in
3d.  Now, that peice of glass is your monitor.  You would
need your eyes to be focoused through your monitor. (hence
this being said in many how-to-see them docs.)  Since the
monitor isn't clear, you need to move your eyes to the same
angle manually, by the usual way of seeing them. Let's post
the image again so you don't have to keep scrolling:
               -o           -o
               -o            -o 
               -o             -o
               -o            -o  
               -o           -o    
               -o            -o
               -o             -o
               -o            -o
               -o           -o
Another way to picture the viewing is instead of the focus 
description, trying to move your eyes apart to see it.  Let's
draw it:
               -o           -o
               -o            -o    XY
    XY         -o             -o
               -o            -o  
              A-o     XY    -oB   
               -o            -o
XY             -o             -o             XY
               -o            -oXY
               -o           -o
Normally, when you are looking at the monitor, your eyes focus
at the same point, shown by the XY's.  If you want to see the 
3D image, you need to make your eyes point at points A+B.  If
the eyes point at different images, as shown, it creates TWO
images!!!  Here it is illistruated:

Flat view, focoused at XY.
Eye 1:                                   Eye2:
  -o           -o                    -o           -o
  -o            -o                   -o            -o    
  -o             -o                  -o             -o
  -o            -o                   -o            -o  
 A-o     XY    -oB                  A-o     XY    -oB   
  -o            -o                   -o            -o
  -o             -o                  -o             -o 
  -o            -o                   -o            -o  
  -o           -o                    -o           -o

3D view, foucused at A and B
Eye 1:                                      Eye2:
  -o                                         -o
  -o                                          -o
  -o                                           -o
  -o                                          -o
 A-o    X                                Y   -oB
  -o                                          -o
  -o                                           -o
  -o                                          -o
  -o                                         -o
As you can see, it splits it up into TWO images, which is always
required to make you see 3D.

Observe:
               -o           -o            
               -o            -o           
               -o             -o          
               -o            -o           
               -o           -o            
               -o            -o           
               -o             -o          
               -o            -o           
               -o           -o            

And 
                          -o            -o
                           -o           -o
                            -o          -o
                           -o           -o
                          -o            -o
                           -o           -o
                            -o          -o
                           -o           -o
                          -o            -o

You will likeley notice that the CLOSER they are to each other,
the closer it is to you.  You will also notice that I contadict
what I said above.  I don't remember the EXACT reason for this,
but it is due to the staring past the monitor needed to view them.
Actually, if I remember correctly, this changes for a few rere
people.


Here's an image:  (Note, this one uses a slightley different
principal to make the 3D, but if you think about it, you see how.)
               -o           -o            -o
               -o            -o           -o
               -o             -o          -o
               -o            -o           -o
               -o           -o            -o
               -o            -o           -o
               -o             -o          -o
               -o            -o           -o
               -o           -o            -o
You will notice that the 3 lines become 4 lines, with the two
in the middle being solid.  On this one, the middle one 
shows up with BOTH outter ones, creating two in-focus lines.
They are z-scale inverted, since as one getts further from one
line, it gets closer to the other.


Sideways ones:  These are my own invention, and they work best when
printed and turned sideways.  These can't be viewed without
turning the monitor or your head sideways.

      ----------------------------





       --_      __--__      __--__
          --__--      --__--

They can be used if a higher level of depth detail is required.
These really only work when printed, and then not very well.



How to make your own:

Simple:

Let's start with a X:

         X

Then make it two

         X                  X

Then more

         X                  X
         X                  X
         X                  X
         X                  X
         X                  X

Then fidle with it:

         X                 X
        X                  X
        X                   X
       X                    X
       X                     X

Now, I don't like it, so I am fliping it:

       X                     X
       X                    X
        X                   X
        X                  X
         X                 X

Now it come out at you!

       XX                   XX
       XX                  XX
        XX                 XX
        XX                XX
         XX               XX

Thicker...

       XXXXXXX         XXXXXXX
       XXXXXXX        XXXXXXX
        XXXXXXX       XXXXXXX
        XXXXXXX      XXXXXXX
         XXXXXXX     XXXXXXX

Real thick!

       \XXXXX/         \XXXXX/
       \XXXXX/        \XXXXX/
        \XXXXX/       \XXXXX/
        \XXXXX/      \XXXXX/
         \XXXXX/     \XXXXX/

Tilted edges. ^^

       \_XXX_/         \_XXX_/
       \_XXX_/        \_XXX_/
        \_XXX_/       \_XXX_/
        \_XXX_/      \_XXX_/
         \_XXX_/     \_XXX_/

Neater^^^

       \_\_/_/         \_\_/_/
       \_\_/_/        \_\_/_/
        \_\_/_/       \_\_/_/
        \_\_/_/      \_\_/_/
         \_\_/_/     \_\_/_/

Uh..

       |_____|         |_____|
       |_____|        |_____|
        |_____|       |_____|
        |_____|      |_____|
         |_____|     |_____|

Steps^^^

       |_____|         |_____|
       |_____|         |_____|
       |_____|        |_____|
       |_____|        |_____|
        |_____|       |_____|
        |_____|       |_____|
        |_____|      |_____|
        |_____|      |_____|
         |_____|     |_____|
         |_____|     |_____|

uhh..

       |_____|         |_____|
       |_____|         |_____|
       |_____|        |_____|
       |_____|        |_____|
       |_____|       |_____|
       |_____|       |_____|
       |_____|      |_____|
       |_____|      |_____|
       |_____|     |_____|
       |_____|     |_____|

Tilted^^^

       /_____/         /_____/
       |_____|         |_____|
       /_____/        /_____/
       |_____|        |_____|
       /_____/       /_____/
       |_____|       |_____|
       /_____/      /_____/
       |_____|      |_____|
       /_____/     /_____/
       |_____|     |_____|

Steps^^^^

       |_____|         /_____/
       |_____|         |_____|
       |_____|        /_____/
       |_____|        |_____|
       |_____|       /_____/
       |_____|       |_____|
       |_____|      /_____/
       |_____|      |_____|
       |_____|     /_____/
       |_____|     |_____|

Same, but useing a tequnique of mine for better Z-plane changes.^^

       |_____|         /_____/         |_____|
       |_____|         |_____|         |_____|
       |_____|        /_____/          |_____|
       |_____|        |_____|          |_____|
       |_____|       /_____/           |_____|
       |_____|       |_____|           |_____|
       |_____|      /_____/            |_____|
       |_____|      |_____|            |_____|
       |_____|     /_____/             |_____|
       |_____|     |_____|             |_____|

Inverted second one^^^^^^^^

       |_____|         /_____/         |_____|
       |_____|         |_____|         |_____|
       |_____|        /_____/          |_____|
       |_____|        |_____|          |_____|
       |_____|       /_____/           |_____|
       |_____|       |_____|           |_____|
       |_____|      /_____/            |_____|
       |_____|      |_____|            |_____|
       |_____|     /_____/             |_____|
       |_____|     |_____|             |_____|

Well, there was a VERY long way of evolveing a very simple thing.

X       X       X       X       X       X       X       X       X
    X      X      X      X      X      X      X      X      X
        X     X     X     X     X     X     X     X     X
            X    X    X    X    X    X    X    X    X

A bunch of lines^^^^^^^^^^^^

X       X       X       X       X       X       X       X       X
    X      X      X      X      X      X      X      X      X
        X     X     X     X     X     X     X     X     X
            X    X    X    X    X    X    X    X    X
        X     X     X     X     X     X     X     X     X
    X      X      X      X      X      X      X      X      X
X       X       X       X       X       X       X       X       X
More lines^^^^^^^^^^^^^^^^

\       \       \       \       |       /       /       /       /
    \      \      \      \      |      /      /      /      /
        \     \     \     \     |     /     /     /     /
            |    |    |    |    |    |    |    |    |
        /     /     /     /     |     \     \     \     \
    /      /      /      /      |      \      \      \      \
/       /       /       /       |       \       \       \       \

Fine, but the middle needs some work^^^^^^^^^^^^^^^^^

HI      HI      HI      HI      HI      HI      HI      HI      HI
    HI     HI     HI     HI     HI     HI     HI     HI     HI
        HI    HI    HI    HI    HI    HI    HI    HI    HI
            HI   HI   HI   HI   HI   HI   HI   HI   HI
        HI    HI    HI    HI    HI    HI    HI    HI    HI
    HI     HI     HI     HI     HI     HI     HI     HI     HI
HI      HI      HI      HI      HI      HI      HI      HI      HI
Nah, I like the above better^^^^^^^^^^^^^^^^^^

 HI      HI      HI      HI      HI      HI      HI      HI      HI
     HI     HI     HI     HI     HI     HI     HI     HI     HI
  HI     HI    HI    HI    HI    HI    HI    HI    HI    HI     HI
HI     HI    HI   HI   HI   HI   HI   HI   HI   HI   HI    HI     HI
  HI     HI    HI    HI    HI    HI    HI    HI    HI    HI     HI
     HI     HI     HI     HI     HI     HI     HI     HI     HI
 HI      HI      HI      HI      HI      HI      HI      HI      HI
Nice!^^^^^^^^^^^^^^^^^^^^^^^^^^

'HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI.
     HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI
  HI     HI''''HI''''HI''''HI''''HI''''HI''''HI''''HI''''HI     HI
HI     HI ---HI---HI---HI---HI---HI---HI---HI---HI---HI--- HI     HI
  HI     HI....HI....HI....HI....HI....HI....HI....HI....HI     HI
     HI.....HI.....HI.....HI.....HI.....HI.....HI.....HI.....HI
.HI......HI......HI......HI......HI......HI......HI......HI......HI.
Cool!^^^^^^^^^^^^^^^^^^^^^

'HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI''''''HI.
     HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI'''''HI
  HI     HI''''HI''''HI''''HI''''HI''''HI''''HI''''HI''''HI     HI
HI     HI ---HI---HI---HI---HI---HI---HI---HI---HI---HI--- HI     HI
HI     HI ---HI---HI---HI---HI---HI---HI---HI---HI---HI--- HI     HI
  HI     HI....HI....HI....HI....HI....HI....HI....HI....HI     HI
     HI.....HI.....HI.....HI.....HI.....HI.....HI.....HI.....HI
.HI......HI......HI......HI......HI......HI......HI......HI......HI.
Better!^^^^^^^^^^^^^

Another 'evolved' picture!!!^^^^^^^^^^^^

Now let's talk about more complicated images:

   :::
   :::
   :::
   :::
   :::
   :::
   :::
   :::
   :::
..:::::..

A tree^^^^^^

   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
   :::           :::           :::           :::           :::
..:::::..     ..:::::..     ..:::::..     ..:::::..     ..:::::..
More trees^^^^^^^^^^

                     O             O
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   :::   ::      :::    ::     :::     ::    :::      ::   :::
   ::: .::::.    :::  .::::.   :::   .::::.  :::    .::::. :::
..:::::..     ..:::::..     ..:::::..     ..:::::..     ..:::::..
More threes in 3D^^^^^^^^^^^^^^  (Hard to view, dots to show)

                     O             O
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   :: :    :::    ::   : :::     ::    :::      ::   :::
   :::   ::.:.   :::    ::  .:.:::     ::    :::      ::   :::
   ::: .::::.    :::  .::::.   :::   .::::.  :::    .::::. :::.
..:::::..     ..:::::..     ..:::::..     ..:::::..     ..:::::..
Yet more threes in 3D^^^^^^^^^^^^^^  (Hard to view, dots to show)
Wow!!!  A forrest!!!

                             X       X
                O O O O O O O O O O O O O O
          O O  O  O  O  O  O  O  O  O  O  O  O O
      O O  O   O   O   O   O   O   O   O   O   O  O O
    O O  O   O    O    O    O    O    O    O    O   O  O O
  O O  O   O    O     O     O     O     O     O    O   O  O O
 O O  O   O    O     O      O      O      O     O    O   O  O O
O O  O   O    O     O      O       O      O     O    O   O  O O
 O O  O   O    O     O      O      O      O     O    O   O  O O
  O O  O   O    O     O     O     O     O     O    O   O  O O
    O O  O   O    O    O    O    O    O    O    O   O  O O
      O O  O   O   O   O   O   O   O   O   O   O  O O
          O O  O  O  O  O  O  O  O  O  O  O  O O
                O O O O O O O O O O O O O O
A tunnel!^^^^^^^^^^^^^^^
 

Basicly, first you create something, and tile it accross:
X          X          X          X          X          X          X
That will show up as flat.


Then add another tiled pattern:
Y          Y          Y          Y          Y          Y          Y
X          X          X          X          X          X          X
It will be the same height.

Add/delete spaces to change depth:

Y         Y           Y          Y         Y          Y           Y
X          X          X          X          X          X          X

Takeing out a space raises the height, and adding one lowers it.

Now, I am useing the entire Y lower, so show it:

Y           Y           Y           Y           Y           Y
X          X          X          X          X          X          X

Now, if i removed spaces, it would be:

Y         Y         Y         Y         Y         Y         Y
X          X          X          X          X          X          X

Let's add a Z:

Y         Y         Y         Y         Y         Y         Y
X          X          X          X          X          X          X
Z           Z           Z           Z           Z           Z

Now an A:

Y         Y         Y         Y         Y         Y         Y
X          X          X          X          X          X          X
Z           Z           Z           Z           Z           Z
A          A          A          A          A          A          A

And a B:

Y         Y         Y         Y         Y         Y         Y
X          X          X          X          X          X          X
Z           Z           Z           Z           Z           Z
A          A          A          A          A          A          A
B         B         B         B         B         B         B

Let's make it solid:

YXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXX
X8888888888X8888888888X8888888888X8888888888X8888888888X8888888888X888
ZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMM
A8888888888A8888888888A8888888888A8888888888A8888888888A8888888888A888
BXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXX

Let's double it, to make it eaiser to see:

                        X           X

YXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXX
YXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXXYXXXXXXXXX
X8888888888X8888888888X8888888888X8888888888X8888888888X8888888888X888
X8888888888X8888888888X8888888888X8888888888X8888888888X8888888888X888
ZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMM
ZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMMMMZMMMMMMMMM
A8888888888A8888888888A8888888888A8888888888A8888888888A8888888888A888
A8888888888A8888888888A8888888888A8888888888A8888888888A8888888888A888
BXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXX
BXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXXBXXXXXXXXX

There we go!

                          @      @
ABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFG
ABCDEFGABCDEFGZABCDEFGABCDEFGAZBCDEFGABCDEFGZABCEEFGZABCDEFGZABCDEFGAB
ABCDEFGABCDEFGZABCDEFGABCDEFGAZBCDEFGABCDEFGABCDEFGZABCDEFGABCDEFGABCD
ABCDEFGABCDEFGZABCDEFGZABCDEFGZABCDEFGABCDEFGABCDEFZGABCDEFGABCDEFGABC
ABCDEFGABCDEFGZABCDEFGABCDEFGAZBCDEFGABCDEFGABCDEFGZABCDEFGABCDEFGABCD
ABCDEFGABCDEFGZABCDEFGABCDEFGAZBCDEFGABCDEFGZABCDEFGZABCDEFGZABCDEFGAB
ABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFG
Howday!!!  This is made by adding Z's where needed.

                  @     @
_.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.--._.-`-._.`-._.-`-._.`-._.`-._.`-._.-`-._.-`-.
_.-`-._.-`-._.--._.-`-._.`-._.-`-._.-`-._-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.--._.--._.--._.-`-._.-`-._.`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.--._.-`-._.`-._.-`-._.-`-._-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.--._.-`-._.`-._.-`-._.`-._.`-._.`-._.-`-._.-`-.
_.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-..-`-._.-`-._.-`-._.-`-_.-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-..-`-._.-`-._.-`-._.-`-._-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-._.-`-._.--._.--._.-`-._.--._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-..-`-._.-`-._.-`-._.-`-._-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-..-`-._.-`-._.-`-._.-`-_.-`-._.-`-._.-`-._.-`-.
_.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-._.-`-.
By deleteing chars^^^^^^^^^^

                 X     X
HI Hi hI hi HI Hi hI hi HI Hi hI hi HI Hi hI hi HI Hi hI hi
HI Hi hI hi HIHi hI hi HIHi hI hi HI H hI i HI i hI hi 
HI Hi hI hi HIHi hI hi HIHi hI hi HI Hi hI i HI Hi hI hi
HI Hi hI hi HIHi hI i HI i hI hi HI Hi hI h HI Hi hI hi 
HI Hi hI hi HIHi hI hi HIHi hI hi HI Hi hI i HI Hi hI hi
HI Hi hI hi HIHi hI hi HIHi hI hi HI i hI h HI HihI hi 
HI Hi hI hi HI Hi hI hi HI Hi hI hi HI Hi hI hi HI Hi hI hi
Get the idea? 
                 X             X
Get the idea? Get the idea? Get the idea? Get the idea? Get the idea? 
Get the idea? Get the idea? Get the idea? Gt the idea? Get the idea? 
Get the ide? Get the idea? Get the idea? Get theidea? Get the idea? 
Get the ide? Get the idea? Get the idea? Get the ide? Get the idea? 
Get the idea? Get the idea?Get the idea? Get the idea?Get the idea? 
Get the ide? Get the idea? Get the idea? Get the ide? Get the idea? 
Get the ide? Get the idea? Get the idea? Get theidea? Get the idea? 
Get the idea? Get the idea? Get the idea? Gt the idea? Get the idea? 
Get the idea? Get the idea? Get the idea? Get the idea? Get the idea? 

                            X             X
ABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGBCDEFGABCDEFGABCDEFGABCDEFABCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGBCDEFGABCDEFGABCDEFGABCDEFABCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGBCDEFGABCDEFGBCDEFGABCDEFGBCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGBCDEFGABCDEFGABCDEFGABCDEFABCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGBCDEFGABCDEFGABCDEFGABCDEFABCDEFGABCDEFGABCDEFGABC
ABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABC

                 @                           @
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ABCDEFGHIJKLMNOPQRSTUVWXYZ!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ACDEEFGHIJLMNOOPQSTUVWXYZ!!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ACDEEFGHIJLMNOOPQRSTVWXXYZ!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ACDEFGHIJKLMNOOPQRSTVWXXYZ!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ACDEEFGHIJKMNOOPQRSTVWXXYZ!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ACDEEFGHIJKMNOOPQSTUVWXYZ!!!
ABCDEFGHIJKLMNOPQRSTUVWXYZ!!ABCDEFGHIJKLMNOPQRSTUVWXYZ!!
(Eye hurter!)^^^^^^^^^^^^

                 R                                   R
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890BCDDEFHIJKKLMNPQRSTUVVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890BCDDEFHIJKKLMNOPRSTTUVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890BCDEFGHIJKKLMNOPRSTTUVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890BCDDEFHIJKKLMNOPRSTTUVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890BCDDEFHIJKKLMNPQRSTUVVWXYZ1234567890
ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890
View this!!!!^^^^^^^^^^^  (If you can!!!)^^^^^^^^^^^^^^

How I made those:
I tiled a pattern, and you delete a charecter where you want to
raise it, and add a charector to lower it.

SOIGFEMTAPKYCN!  Sounds german.....

I sometimes work in 3D, but many people say they can't do this.


RED/BLUE 3D images in ASCII:
You can also create the red/blue type images in HTML, just use red
(FF0000), and Blue (0000FF), and draw something like:

        XXXX
       XX XX
  red->XX  XX<-blue
      XX   XX

And see it through the glasses.

The further apart, the futher away. See below for details.

I made this:
      XX   XX
       XX  XX
       XX XX
        XXXX
         XX
         XX
        XXXX
       XX XX
       XX  XX
      XX   XX
      XX    XX

In these colors:
      BB   RR
       BB  RR
       BB RR
        BBRR
         BR
         RB
        RRBB
       RR BB
       RR  BB
      RR   BB
      RR    BB

It generates remarkable depth.


You also can create color stereograms, which allow much extra
detail added.  I won't add any to this post, but I think you
get the picture. (pun known)


On clarification of the closer-> further rule, that is it is
reversed for Stereograms and Anaglyphs, in the folowing ways:
For anaglyphs (red/blue images), the futher apart, the closer
the image is. For stereograms, the closer together the charecters
are, the closer to you it appers.  Actually, for anaglyphs, it
reverses if the colors are reversed, as shown by the X in color.




This FAQ is not yet complete, but it does answer many points of
stereogram creation. 

I am working (working:  I have been _working_ on part of another
FAQ for another group, It's gotten around 2 lines done a day...)
on a new FAQ version, which will have less annoying pictures, and
will include a link list of pages and programs related to
stereograms.  Look for it soon.

Would the person who always posts the FAQs (colin?) please add this
to the perodicly-posted list?



Copyright 1997, Randy Gardner (randyg@slip.net).


-- 
--randyg@slip.net  (Randy Gardner)
--http://www.slip.net/~randyg/index.htm  - *New*  Download a maze
  program that lets you actually walk *inside* the maze!!



