This applet implements Chris Langton's Ant, or Virtual Ant, or Vant. More comments below... Push the ">" button to play. (Netscape users: trouble? see the note below.)

This vant follows the rule: if you're on a white square, turn it black, turn left and step forward. If you're on a black square, turn it white, turn right and step forward. This is the simplest kind of Vant, rule "number 2." More complicated vant rules have been explored; check these links for more writings and software.

This vant is running on a grid that wraps around from left to right and top to bottom. Also, the applet lets you initialize the grid with patterns of dots instead of just all white. I think this setup shows more fun behavior--in particular, sometimes it tears down and rebuilds things it's already built, because of a special kind of reversability the number 2 vant rule has in a wrap-around world.

The source code is in LangtonsAnt.java. The CheapVector class is in CheapVector.java. This applet started out as a Life program that Peter N Lewis <peter@stairways.com.au> wrote and MetroWorks distributed with their Code Warrior development environment.

Netscape note:

On Netscape--at least version 4.6 on the Mac, this applet sometimes clears without redrawing. Some tricks that sometimes help: Debugging help appreciated.