1. Chapayev CS426 04/04/08

2. Concept Vasilyev Brothers' Chapayev, 1934 Alternative way of playing Checkers is known as Chapayev game in the countries of former Soviet Union. The game is named after Vasily Ivanovich Chapayev (1887-1919) -- the legendary hero of Civil War in Russia. The goal of the game is by flicking player’s own checkers, to sweep the opponent’s checkers off the chessboard.

3. Game rules Red Army starts the game. Player flicks his own checker to sweep the opponent’s checkers off the board. If player did not sweep any of opponent’s checker, or lost his own checker, the opponent takes the next move. The players who knocks out all opponent’s checkers wins the battle. The winner moves one line forward and starts a new battle. If player won the battle without loosing any of his checkers, he moves two lines forward. If the line is occupied by the opponent, the opponent should retreat. The player who passes the whole board wins the game.

4. Flick controller The most natural way to control the game: Flick the mouse wheel! *** WARNING: *** We are not responsible for any equipment you break! Notice: Not all mouse models work properly. Microsoft mice are GOOD! Logitech mice are not always good (but some models work too)

5. Mouse wheel response Output from Microsoft Basic Optical Mouse, model X09-13962, at different flick intensities Flick intensity is calculated by linear fitting of the beginning of response curve

6. Graphic loop The queue of scenes to render is organized into linked list. Main loop (fast) adds new scenes to the top of the list. Graphic loop (slow) takes the top scene and renders it. When done, it deletes all previous scenes.

7. Physics The only force in the model is friction: Collisions are easy to detect analytically. The result of collision can be also found analytically using the conservation laws for momentum and energy: Model needs only 2 independent parameters: friction and energy dissipation. a b

8. AI AI should be smart enough to keep the game challenging. AI should be stupid enough to let human player win. Current implementation: Generate a set of random moves: Random checker Random direction Random velocity Calculate the result of each move Select the best move

9. Things to do… Better interface Better AI Scoring Sounds Music Main screen Settings screen Hall of Fame Tuning parameters Buy some beer Anything else?

10. Thank you!