No Humans Allowed: Joust Being Played Automatically By Computer


  • Christian Gingras was one of the early marathon players of the 1982 arcade classic by Williams Electronics called Joust.  Culminating in a 2-day marathon game reaching 98 million points.
  • He was so engrossed with game design that he reverse engineered the Robotron 2084 program code in the mid-80s as a self-exercise in computer programming.
  • With the advent of MAME‘s software emulation of the arcade classics, he wanted to see if it was possible to automate the game to play against itself.
  • “It took me a few hundreds of hours, more than 3 months spread over about 5 years to study Mame in detail. The patch to Mame.exe by itself took about a week to create.”
  • What you see below is his successful venture, which played by itself for almost 2 weeks straight during one testing phase! 
  • Watch example via YOUTUBE

Contact Info

  • Christian is French-Canadian, raised in Canada and currently residing in California
  • If you wish to contact him he can be found on Facebook

Quick Download: 

  1. Joust Automated Gameplay MAME files
  2. Extract the ZIP contents to your computer (can extract with 7-ZIP)
  3. Click on the JJ.bat file to watch a previously recorded gameplay which is done with no human intervention on controls!
  4. Youtube video of the game playing by itself

FURTHER DETAILS (written by Christian July 2013, un-altered by author)

SUMMARY- In case you are interested : I created an input script for Mame which simulate the flapping and left/right command of the birds, like if somebody was actually pressing. I used to let the two birds complete hundreds of wave together.

The idea came from the tests I was making with a real Joust board : connecting a 555 oscilator on the flap input and forcing one bird to go left and the other birds go right. With bonus set to 1000 points, they could survive indefinitely and complete wave after wave. I let the machine play for two weeks, non stop, for example

OVERVIEW: I created a binary file that simulate the flap/joystick (or keyboard) input (Mame can save, then replay such file) of the two players. I modified Mame executable itself to make it repeat the sequence to near the beginning when reaching the end. The first few key press simulated are “Insert Coin” (a few times) then “2”, start the game in two player mode. The two birds start flying like crazy as fast as a Shadow Lord after wave 56 and difficulty level 9. They exercise their brake by
running and stopping.  They mostly kill each other, both sometime hit a buzzard , or a pterodactyl.

MAME SETUP: Soon after starting, I usually activate the cheat mode where the two players never die. The other option is to set the bonus to 1000 points. The first option is better as it allow the normal sound to be heard. With 1000 point bonus, all we can hear is the bonus sound or the player dead sound… maybe a few flap sound.

Yes, it is a small file (about 20K) which follow the same format as the Mame “capture joystick / replay” option. However, I also modified Mame.exe directly to make it loop indefinitely on the joystick replay file. That change was made on rev 0.63, if my memory is good. This executable is about 10 Meg. This rev works even under Windows 8. I can probably patch a much more recent version of Mame if this appear useful.

I recommend to press “TAB”, select the cheat mode and select the infinite life, if you want the game reach really interesting levels.
The tab menu is always available in normal mode as well as in this mode of “replay input”.

Taking It Into the Future

There is a whole sub-culture involved in the challenge of automating games.  Feel free to take the inspiration of Christian’s experimentation and do amazing things with innovative development.  Maybe we will have robotic vision interfaces capable of playing Robotron 2084, someday?!

Return to the main page for Christian HERE

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