Frisian draughts

class draughts.boards.frisian.Board(starting_position: ndarray = None, turn: Color = None)[source]

Board for Frisian draughts.

Game rules:

Board size: 10x10
Besides capturing diagonally, one can also capture horizontally and vertically.
Every piece can thus capture in eight directions
If a king and a man can play a capture sequence of equal value,
it is always forced to play with the king.
If a player has one or more kings on the board but also has one or more men left,
it is not allowed to play more than three non-capturing moves in a row with the same king. If no capture is available for a king after its third non-capturing move, one is forced to play with a different king or a man. After that one can play any move with that king again, but of course again only three times in a row if it doesn’t capture. This rule does not apply for a player that has no more men left (only kings on the board).

Winning and drawing

When one player has two kings and the other player has one king,
the game is drawn after both players made 7 moves.
When both players have one king left, the game is drawn after both players made 2 moves.
The official rules state that the game is drawn immediately when two kings are left unless either player can win by force (which means the other king can be captured immediately or will necessarily be captured next move). As we currently can’t distinguish the positions that win by force on lidraughts, this rule is implemented by always allowing 2 more moves to win the game.