A Board abstraction for deterministic two player games. This allows for code to be generic over the actual game, so it only needs to written once.

Features

Currently, the implemented games are:

• Super/Ultimate tic-tac-toe in the module sttt.
• Ataxx in the module ataxx.
• Chess in the module chess, implemented as a simple wrapper around the chess crate.

Notable things currently implemented in this crate that work for any Board:

• Game-playing algorithms, specifically:
  • RandomBot, which simply picks a random move.
  • RolloutBot, which simulates a fixed number of random games for each possible move and picks the one with the best win probability.
  • MinimaxBot, which picks the best move as evaluated by a customizable heuristic at a fixed depth. (implemented as alpha-beta negamax).
  • MCTSBot, which picks the best move as found by Monte Carlo Tree Search.
• Random board generation functions, see board_gen.
• A bot vs bot game runner to compare playing strength, see bot_game.
• Simple game statistics (perft, random game length) which can be used to test Board implementations.

Examples

List the available moves on a board and play a random one.

let mut board = AtaxxBoard::default();
println!("{}", board);

board.available_moves().for_each(|mv| {
println!("{:?}", mv)
});

let mv = board.random_available_move(&mut rng);
println!("Picked move {:?}", mv);
board.play(mv);
println!("{}", board);

Get the best move according to MCTS

let board = AtaxxBoard::default();
println!("{}", board);

let mut bot = MCTSBot::new(1000, 2.0, thread_rng());
println!("{:?}", bot.select_move(&board))