Tron Light Cycles

Tron is a popular video game that has been implemented in arcades and PC's with different rule variations. It is based upon a segment of the movie Tron [137], where the characters rode Light Cycles, futuristic motorcycles that leave a solid trail behind them (fig. 3.1).

  

Figure 3.1: Light Cycles. Still from the movie Tron.

The Tron-Light Cycles game is a contest between opponents who move at constant, identical speeds, erecting walls wherever they pass and turning only at right angles. As the game advances, the 2D game arena progressively fills with walls and eventually one opponent crashes, losing the game.

Tron requires quick reactions and spatial-topological reasoning at the same time. In our version, the two players (one human, one agent) start in the middle region of the screen, moving in the same direction. The edges are not considered ``walls''; players move past them and reappear on the opposite side, thus creating a toroidal game arena. The size of the arena is 256256 pixels.

Fig. 3.2 shows the Java version of our Tron game, running inside an Internet browser application. A Java agent is constrained by the Java Virtual Machine of the browser, an environment very limited in speed and resources. At the time when our experiment was conceived, Java was a new technology and only small, simple programs would run reliably on commercial web browsers. The minimalistic memory, CPU and graphics requirements of Tron made it an ideal choice for the experiment.

  

Figure 3.2: The Tron page: Tron runs as an applet inside an Internet browser. Arrows have been added to indicate direction of movement, and dotted lines to show the sensors of an artificial agent.