def possible_moves(self, game_state):
possible_moves = []
other_pieces = game_state.pieces_by_position
offsets = [[-2, -1], [-2, 1],
[-1, -2], [-1, 2],
[1, -2], [1, 2],
[2, -1], [2, 1]]
for offset in offsets:
new_position = (self.position[0] + offset[0],
self.position[1] + offset[1])
# check if new square is on the board...
if 0 <= new_position[0] <= 7 and 0 <= new_position[1] <= 7:
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, do nothing
pass
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
return possible_moves
def possible_moves(self, game_state):
possible_moves = []
other_pieces = game_state.pieces_by_position
offsets = [[-1,-1],[-1,0],[-1,1],
[0,-1], [0,1],
[1,-1], [1,0], [1,1]]
for offset in offsets:
new_position = (self.position[0] + offset[0],
self.position[1] + offset[1])
# Check if new square is on the board
if 0 <= new_position[0] <= 7 and 0 <= new_position[1] <= 7:
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, can't do anything
pass
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
# Handle castling
can_castle = game_state.can_castle[self.colour]
if can_castle["o-o"]:
if self.colour == "white":
rook = other_pieces.get((7,0))
if rook and rook.colour == "white":
possible_moves.append(moves.Castle(self, self.position, (6,0), rook, rook.position, (5,0)))
elif self.colour == "black":
rook = other_pieces.get((7,7))
if rook and rook.colour == "black":
possible_moves.append(moves.Castle(self, self.position, (6,7), rook, rook.position, (5,7)))
if can_castle["o-o-o"]:
if self.colour == "white":
rook = other_pieces.get((0,0))
if rook and rook.colour == "white":
possible_moves.append(moves.Castle(self, self.position, (2,0), rook, rook.position, (3,0)))
elif self.colour == "black":
rook = other_pieces.get((0,7))
if rook and rook.colour == "black":
possible_moves.append(moves.Castle(self, self.position, (2,7), rook, rook.position, (3,7)))
return possible_moves
def possible_moves(self, game_state):
possible_moves = []
other_pieces = game_state.pieces_by_position
# Moving left
k = 1
while self.position[0] - k >= 0:
new_position = self.position[0] - k, self.position[1]
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving right
k = 1
while self.position[0] + k <= 7:
new_position = self.position[0] + k, self.position[1]
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving up
k = 1
while self.position[1] + k <= 7:
new_position = self.position[0], self.position[1] + k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving down
k = 1
while self.position[1] - k >= 0:
new_position = self.position[0], self.position[1] - k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving up-left
k = 1
while self.position[0] - k >= 0 and self.position[1] + k <= 7:
new_position = self.position[0] - k, self.position[1] + k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving up-right
k = 1
while self.position[0] + k <= 7 and self.position[1] + k <= 7:
new_position = self.position[0] + k, self.position[1] + k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving down-left
k = 1
while self.position[0] - k >= 0 and self.position[1] - k >= 0:
new_position = self.position[0] - k, self.position[1] - k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
# Moving down-right
k = 1
while self.position[0] + k <= 7 and self.position[1] - k >= 0:
new_position = self.position[0] + k, self.position[1] - k
if new_position not in other_pieces:
# Square is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, new_position))
k += 1
elif other_pieces[new_position].colour == self.colour:
# Square is occupied by friendly piece, stop
break
else:
# Square is occupied by enemy piece, can capture
possible_moves.append(moves.Capture(self, self.position, new_position, other_pieces[new_position]))
break
return possible_moves
def possible_moves(self, game_state):
possible_moves = []
other_pieces = game_state.pieces_by_position
if self.colour == "white":
# can only move upwards
if self.moved:
possible_squares = [(self.position[0], self.position[1] + 1)]
for square in possible_squares:
if not (0 <= square[0] <= 7 and 0 <= square[1] <= 7):
# Square not on board, can't go further
break
elif square not in other_pieces:
# Space is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, square))
elif other_pieces[square].colour == self.colour:
# Space is occupied by friendly piece, stop
break
else:
# Space is occupied by enemy piece, stop
break
else:
possible_squares = [(self.position[0], self.position[1] + 1),
(self.position[0], self.position[1] + 2)]
for square in possible_squares:
if not (0 <= square[0] <= 7 and 0 <= square[1] <= 7):
# Square not on board, can't go further
break
elif square not in other_pieces:
# Space is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, square))
elif other_pieces[square].colour == self.colour:
# Space is occupied by friendly piece, stop
break
else:
# Space is occupied by enemy piece, stop
break
# now deal with standard captures
possible_capture_squares = [(self.position[0] - 1, self.position[1] + 1),
(self.position[0] + 1, self.position[1] + 1)]
for square in possible_capture_squares:
# if square is on the board...
if 0 <= square[0] <= 7 and 0 <= square[1] <= 7:
# if square is occupied by an enemy piece
if square in other_pieces and other_pieces[square].colour != self.colour:
possible_moves.append(moves.Capture(self, self.position, square, other_pieces[square]))
# now deal with en passant
# we make sure we have a last made move; i.e. this isn't the first turn
if len(game_state.move_history) > 0:
if self.position[1] == 4:
# white pawn must be on its fifth rank
adjacent_squares = [(self.position[0] - 1, self.position[1]),
(self.position[0] + 1, self.position[1])]
last_move_made = game_state.move_history[-1]
# need to check:
# - the last move was a pawn double move
# - into an adjacent square
conditions = (isinstance(last_move_made, moves.Translation) and
isinstance(last_move_made.piece, Pawn) and
last_move_made.piece.position in adjacent_squares and
abs(last_move_made.old_position[1] - last_move_made.new_position[1]) == 2)
if conditions:
square = (last_move_made.piece.position[0], last_move_made.piece.position[1] + 1)
possible_moves.append(moves.EnPassant(self, self.position, square, last_move_made.piece))
else:
# handle black pawns- they can only move down
if self.moved:
possible_squares = [(self.position[0], self.position[1] - 1)]
for square in possible_squares:
if not (0 <= square[0] <= 7 and 0 <= square[1] <= 7):
# Square not on board, can't go further
break
elif square not in other_pieces:
# Space is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, square))
elif other_pieces[square].colour == self.colour:
# Space is occupied by friendly piece, stop
break
else:
# Space is occupied by enemy piece, stop
break
else:
possible_squares = [(self.position[0], self.position[1] - 1),
(self.position[0], self.position[1] - 2)]
for square in possible_squares:
if not (0 <= square[0] <= 7 and 0 <= square[1] <= 7):
# Square not on board, can't go further
break
elif square not in other_pieces:
# Space is empty, add to possible_moves
possible_moves.append(moves.Translation(self, self.position, square))
elif other_pieces[square].colour == self.colour:
# Space is occupied by friendly piece, stop
break
else:
# Space is occupied by enemy piece, stop
break
# now deal with standard captures
possible_capture_squares = [(self.position[0] - 1, self.position[1] - 1),
(self.position[0] + 1, self.position[1] - 1)]
for square in possible_capture_squares:
# if square is on the board...
if 0 <= square[0] <= 7 and 0 <= square[1] <= 7:
# if square is occupied by an enemy piece
if square in other_pieces and other_pieces[square].colour != self.colour:
possible_moves.append(moves.Capture(self, self.position, square, other_pieces[square]))
# now deal with en passant
# we make sure we have a last made move; i.e. this isn't the first turn
if len(game_state.move_history) > 0:
if self.position[1] == 3:
# black pawn must be on its fifth rank
adjacent_squares = [(self.position[0] - 1, self.position[1]),
(self.position[0] + 1, self.position[1])]
last_move_made = game_state.move_history[-1]
# need to check:
# - the last move was a pawn double move
# - into an adjacent square
conditions = (isinstance(last_move_made, moves.Translation) and
isinstance(last_move_made.piece, Pawn) and
last_move_made.piece.position in adjacent_squares and
abs(last_move_made.old_position[1] - last_move_made.new_position[1]) == 2)
if conditions:
square = (last_move_made.piece.position[0], last_move_made.piece.position[1] - 1)
possible_moves.append(moves.EnPassant(self, self.position, square, other_pieces[square]))
return possible_moves