****************************************
			      ANNOUNCING
	       The Availability of Cellsim version 2.5
	       ****************************************
				  by
			    Chris Langton
			    (cgl@lanl.gov)
				 and
			    Dave Hiebeler
		     (hiebeler@think.com)

  Version 2.5 of Cellsim is a SunView-based cellular automata simulator
allowing interactive specification, editing, running, and analysis of
1- and 2-D CA's.  It will run on Sun-3's, -4's, and Sparc stations,
color or B&W.

  You can also use Cellsim to attach to a Connection Machine, and use either
the CM Frame Buffer or the Sun to display your images; you can do this either
directly from a CM front-end, or remotely through the network.  Cellsim on the
CM allows you to use arbitrarily complex update-functions and "cells".

  With these recent enhancements, Cellsim is now becoming a tool flexible
enough to use for the exploration of lattice-based systems in general.
Besides running traditional CAs, you can also do things such as run computed
functions of up to 256 states per cell, use floating-point values, or run
large ensembles of 1-D systems.  Running on the Connection Machine also
give you the ability to do complex data-analysis on the fly, in parallel.

Since version 2.0 was never "officially" released, the changes since
version 1.5 are listed below:

1) 256-state "computed-function" rules can now be used, in addition to
   lookup-tables, on both the Sun and CM.  This greatly expands the range
   of rules you can investigate.

2) You can now invoke Cellsim once, and change the neighborhood or number
   of states or image size, without having to call up a new Cellsim.
   Cellsim will also automatically switch into the proper neighborhood
   when you load a rule, or the proper image size when you load an image,
   unless you disable that feature.

3) The "general" random image-generation routine is much more general now.

4) You can create lookup-tables using "Lambda" or "Rho" parameters.
   The Lambda parameter is described in the article "Studying Artificial
   Life with Cellular Automata" by Chris Langton, in Physica 22D (1986),
   and more recently in "Computation at the Edge of Chaos: Phase Transitions
   and Emergent Computation" by C. Langton, in the proceedings of the
   "Emergent Computation" conference, to be published in a special issue of
   Physica D, 1990.

5) The middle mouse-button can be used to reselect the last item selected
   from any of the menus (except the "Defaults" menu) in the control-panel.

6) You can save images in Sun raster format in addition to Cellsim's "raw
   data" format.

7) The process of writing C code to generate lookup tables has been
   made easier.

8) Tilde-expansion and wildcard-expansion is now performed on
   filenames.  For example, you can now specify names such as
   "~/Images/xyz.64x" or "xyz*.m4" when loading or saving images,
   transition tables, colormaps, etc. 

9) You can attach to a Connection Machine, and run the actual computations
   on the CM, using either the CM frame-buffer or the Sun to display the
   images.

10) A new "defaults" menu which lets you bring up popup windows, so
    you may change some of the behaviors of Cellsim.

11) There are 5 user-definable "sequences" which you can "teach" series of
    button-presses or menu-item selections.  So if there is some sequence
    of commands you routinely use, you can define a sequence to hold those
    commands, and call them up with the single press of a mouse-button.

12) You can now draw lines and circles in the array, from the "Draw" menu.
    (The "Draw" menu now contains the "random" image-generation routines).

13) The maximum possible image-size is now 512x512, instead of 256x256

	       ****************************************

You can obtain Cellsim via anonymous FTP to archive.cs.rpi.edu (128.113.53.18).
Use the login "anonymous", and your e-mail address as password.  Then,
do the following commands:
  cd pub/cellsim
  bin
  get cellsim_2.5.tar.Z

That will transfer the tar file in binary mode.  Once you've obtained the
tar file, you should uncompress it and extract its contents as follows:
  uncompress cellsim_2.5.tar.Z
  tar xvf cellsim_2.5.tar

Once you've done that, go to the "V2.5" directory, and follow instructions
in the "README" and "Installation" files there.


  If you are unable to use FTP, then send either a 1/4" or 1/2" tape to:

    Chris Langton
    Theoretical Division
    T-13, MS B213
    Los Alamos National Laboratory
    Los Alamos, NM 87545  USA

If you send 1/2" tape, please specify the density to use.

For those of you in Europe or Japan, we are sending copies of Cellsim to
people who have agreed to serve as distribution sites there (tapes are on
the way, guys!)  We'll follow-up with information on how to get it from them,
once they have received the tapes and verified that they have working copies.

If you obtain Cellsim via FTP, please send Chris Langton (cgl@lanl.gov) a
message, so that you can be placed on a distribution mailing-list for
announcements of bug-fixes, new releases, announcement of new libraries,
and so on.  This is very important, so that you can be kept up-to-date
with Cellsim as it evolves.


Cheers!

Chris Langton
Dave Hiebeler