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The Classic CHAOS Software Goes Multiplatform


Today I got around to using a fix that allows our old CHAOS software to run, I think, on every platform. See my CHAOS page for full details, and for the free downloads. Thanks to “Torbjørn Pettersen” and “Jac” for having advised me.

Summarizing some of that that page says, CHAOS is a shareware release of James Gleick’s CHAOS:the Software.  We provide both the complete executable and the source code for the 1990 Autodesk release based on the wonderful book Chaos, by James Gleick

The software was written by  Josh Gordon, Rudy Rucker and John Walker for Autodesk, Inc., with Josh Gordon doing the lion’s share of the programming work. It is our hope that this shareware release will allow educators, students and dabblers to freely use our software. Great for classroom use or individual exploration.

CHAOS can presently be run, using the free DOSBox ware, under Windows, Linux, Mac OS X, and other platforms.

CHAOS has six modules.

1. MANDEL. A fast Mandelbrot set program, incorporating: quadratic and cubic Mandelbrots, various fill patterns, quadratic and cubic Julias, and the gnarly "cubic Mandelbrot catalog" set that I call the Rudy set. For more up-to-date info on these fractals, you can also look at my 2010 formula files and parameter files for the commercial Ultra Fractal software as described on mys blog post, “The Rudy Set as the ultimate Cubic Mandelbrot.”

2. MAGNETS… A Pendulum and Magnets program showing chaotic physical motion.

3. ATTRACT. A Strange Attractors program showing some of the Hall of Famers as the Lorenz Attractor, the Logistic Map, the Yorke Attractor, the Henon Attractor, etc.

4. GAME. A "Chaos Game", which is a Barnsley Fractals program showing Iterated Function System fractals such as the famous "fern".

5. FORGE. A "Fractal Forgeries" program that shows mountain ranges based on random fractals.

6. TOY. A "Toy Universes" program that shows some cellular automata.


9 Responses to “The Classic CHAOS Software Goes Multiplatform”

  1. Ian Dennis Miller Says:

    It does work under OS X, when executed inside DOSbox. DOSbox provides some hotkeys that are useful for changing the emulation timing, since some older games relied on slower machines in order to render properly. By default, DOSbox runs significantly slower than your actual hardware is capable of. Some of the CHAOS software will benefit from turning the speed up (e.g. MANDEL).

  2. John Baker Says:

    Hello! Your article was re-posted (via RSS) into Buzz, my favorite place to learn new things. Thank you for sharing this with everyone!

  3. linus robinson Says:

    ok thats really cool…. yet dont forget the Chaos Continuum….

  4. Josh Gordon Says:

    It’s pretty amazing seeing software I wrote on a 386 DOS box, 21 years ago, running on OSX Lion… Hey Rudy, what year did we start working on this? Did we start in ’89 or ’90?

  5. Rudy Says:

    Josh, good to hear from you. I’m glad you’re using the DOSBox Chaos fix. Yes, Chaos is a wonderful program still. I believe we worked on Chaos all through 1989 and 1990, and it shipped in 1991.

    You once remarked that there was an Easter egg type key code for making the Chaos Mandelbrot run in higher rez, but I don’t know what it was, if I ever knew. In any case, I was recently playing with some superzoomed versions of our more exotic higher-order Mandelbrot-type sets using Ultrafractal, I posted a lot about that on my blog at

    Would be great to get together and catch up sometime, send me an email if you like.

  6. Chip Mefford Says:

    I thought ya’ll would appreciate this:
    I was just cleaning out my desk, and found my old chaos disks, and was pondering pitching them in the bin. I thought this software was great, and expected more stuff like this from Autodesk, et al. But alas, twas not to be. Had a lot of fun with this software. It drove me to build and tune faster boxes, trying to get better renderings. Nice work!

    Anyway, just for fun:

  7. Phil Says:

    I have the original CHAOS:the software, manual and all.

    Had to run it on a 286. I think the first one or two levels of the Mandelbrot set
    displayed in reasonable time, but after that I used to count the dots displaying
    across the horizontal scan line.

    Just started running it again in DOS Box, no troubles at all on my dual core Intel.
    Very glad the program copied over to my hard drive from floppy disk.
    (That wouldn’t happen these days, would it?).

    Picked up “The COSMIC Blueprint” book by Paul Davis from a Second hand book shop.
    Got me interested in chaos again. Need to study more Maths though :(
    At 57 years of age inspiration to do maths only comes around once every purple
    poker dot moon. To many great computer games to play and only a finite
    life time.

    Oh well, Just happen to stumble on to this site looking to see if there were any free
    chaos software floating around on the net.


  8. Rich Harkness Says:

    I would like to run the simulations (especially “magnets” and “attract”) that I’ve downloaded and unzipped but being no computer expert have no idea what to do next. I’m using a MAC mini with OSX 10.7.5. First, am I correct that these are dynamic models that show the results of the equations being plotted as movies? If so, can you give me some details as to how to run them? (I’m trying to better understand chaos in order to write a non-technical book about systems) Thanks, Rich Harkness BSEE, with 1975 PhD in Urban Systems Planning.

  9. Rudy Says:

    Rich, I’m sorry, but I don’t have the time to help you with this. Also, it’s been a long time since I used the program, so the info isn’t fresh in my mind. I do recall that we had fairly informative help files with the software, and that if you tinkered with it, you’d soon get an idea of what was going on. If you can get the Chaos program modules to run on your machine just play with them for an hour and I think you’ll learn something. And, as I say, don’t forget to take a look at the help files.

    Re. your first question, yes, the “magnets” and “attract” modules are bit like realtime movies, being generated on the fly.

    Unfornately we never digitized the manual that came with the CHAOS program, and I’m not sure I’ll ever do this.

    If CHAOS doesn’t do what you need, you might also try Googling for “java chaos program” which will lead you to some online apps.

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