Light Cycles

Goal

Your bike keeps moving forward without ever stopping and leaves behind it an impassable wall of light. Touch a wall, the edge of the arena or another rider, and you are eliminated. The last rider on the track wins the round; the first to win the chosen number of rounds wins the match.

How it works

• You face one, two or three AIs; the AIs also fight each other.
• If you crash, the round goes to the AIs. If the last riders crash at the same instant, the round is a draw and is replayed.
• The walls of an eliminated rider fade away after a short moment.
• Points: each cell travelled is worth 1 point, each round won 400 points per opponent, and the match win 1,000 points.

Controls

• Keyboard: arrows or WASD to choose the direction; P or Esc to pause.
• Touch: swipe the screen in the direction you want, or use the two buttons to turn left or right.
• Quick turns are remembered: two presses in a row make a tight U-turn over two cells.

About the AI

At every cell, each AI computes the Voronoi partition of the arena: the cells it could reach before its closest opponent. It then explores the next turns of both riders with an iterative-deepening alpha-beta search, taking head-on collisions into account. When the riders are separated, it switches to filling mode and maximizes the length of its path (checkerboard parity bound). At the lower levels, the search is shortened or replaced by more naive heuristics, with deliberate slips.