嗨!我正在制作一个国际象棋引擎，但 make/unmake 方法有一些问题。

我有一个 Piece 类，用于保存棋子的类型(兵、后等)和位置，还有一个 Move 类，用于保存目标方格、移动的棋子和捕获的棋子。

问题是，当我调用 makeMove 方法时，它会将棋子的位置更改为 Piece 对象内的目标方 block 。但现在，我无法使用 Move 对象调用 unmakeMove，因为现在我没有关于移动来自何处的信息，因为我刚刚更改了棋子的位置。您将如何解决这个问题？

非常感谢!

class Board:
# Previous methods omitted. 

    def makeMove(self, move, player):
        """ Makes a move on the board and changes Piece object. Returns None. """
        self.moved_piece = move.getPiece()
        self.captured_piece = move.getCapturedPiece(self)

        if self.captured_piece: # Remove captured piece from player's piece dict. 
            player.removePiece(self.captured_piece)

        self.setPiece(move.getTargetSquare(), self.moved_piece) # Set moved piece on target square.
        self.setPiece(self.moved_piece.getPosition(), EMPTY) # Make the origin square empty.
        self.moved_piece.changePosition(move.getTargetSquare()) # Change piece object's position.

    def unmakeMove(self, move, player):
        """ Unmakes a move. Returns None. """
        self.moved_piece = move.getPiece()
        self.captured_piece = move.getCapturedPiece(self)

        self.setPiece(self.moved_piece.getPosition(), captured_piece) # Set captured piece or empty square to target square.
        # Set piece to original square. HOW !?

1 Câu trả lời

根据我的评论和 link on the Memento pattern Fred Larson 发布的内容是您可能想要执行的操作的示例实现:

class Engine(object):
    định nghĩa __init__(bản thân):
        self.board = Board()
        self.move_list = []

    def make_move(self, from, to):
        #board.makeMove returns a "memento object".
        self.move_list.append(board.makeMove(from, to))
        ...

    def undo_move(self):
        board.undo(self.move_list.pop())
    ...
    ...

假设您有一个具有以下结构的移动对象:

class Move(object):
    def __init__(self, from_coords, to_coords, capture=None):
        self.from = from_coords
        self.to = to_coords
        self.capture = capture

Của bạn Board 对象将实现以下方法:

class Board(object):
    ...
    def make_move(self, from_coords, to_coords):
        #move logic here
        return Move(from_coords, to_coords, capturedPiece)

    def undo_move(self, move_object):
        self.make_move(move_object.to_coords, move_object.from_coords)
        self.uncapture(move_object.capture, move_object.to_coords)

显然，上面的代码只是概念性的。实际的实现取决于其余代码的结构。

注意:我为 Move 对象使用了一个类，因为属性访问是明确且易于遵循的。实际上，像这样基本的对象可能只是一个 (from, to, capturepiece) 形式的元组。

关于python - 国际象棋编程的走棋和撤棋，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/11873180/