def generate_pawn_blocker_masks():
"""Mask to get the square directly in front of a pawn"""
def create_blocker(square, direction):
x, y = get_coordinate(square)
blockerSquare = get_square(x, y + direction)
return Bitboard(blockerSquare) if 0 <= blockerSquare < 64 else 0
whiteMasks, blackMasks = {}, {}
for square in range(64):
squareBitboard = Bitboard(square)
whiteMasks[squareBitboard] = create_blocker(square, -1)
blackMasks[squareBitboard] = create_blocker(square, 1)
return whiteMasks, blackMasks
def generate_ray_masks(reverse=False):
"""Generates file, rank, diagonal, and antidiagonal masks
Example Diagonal Mask Example Antidiagonal Mask
00000010 10000000
00000100 01000000
00001000 00100000
00100000 00010000
01000000 00001000
10000000 00000100
00000000 00000010
00000000 00000001
Example File Mask Example Rank Mask
00000010 00000000
00000010 11111111
00000010 00000000
00000010 00000000
00000010 00000000
00000010 00000000
00000010 00000000
00000010 00000000
"""
# create a mask for each rank
rankMaskList = []
for rank in range(8):
rankStartIndex = rank * 8
rankSquares = range(rankStartIndex, rankStartIndex + 8)
rankMask = Bitboard(*rankSquares)
rankMaskList.append(rankMask)
# create a mask for each file
fileMaskList = []
for file in range(8):
fileSquares = range(file, 64, 8)
fileMask = Bitboard(*fileSquares)
fileMaskList.append(fileMask)
maskLists = [
rankMaskList, fileMaskList, DIAGONAL_MASK_LIST, ANTI_DIAGONAL_MASK_LIST
]
# iterate through each square on the board and add the rank, file,
# diagonal, and antidiagonal masks that the square is a part of. This
# way, a square's mask index does not need to be computed for retreival
maskDicts = (rankMasks, fileMasks, diagonalMasks,
antiDiagonalMasks) = {}, {}, {}, {}
for square in range(64):
fileIndex, rankIndex = get_coordinate(square)
diagonalIndex = (square // 8) + (square % 8)
antiDiagonalIndex = (square // 8) + 7 - (square % 8)
maskIndecies = [rankIndex, fileIndex, diagonalIndex, antiDiagonalIndex]
for dict, list, index in zip(maskDicts, maskLists, maskIndecies):
mask = list[index]
if reverse:
dict[Bitboard(square)] = reverse_bitboard(mask)
else:
dict[Bitboard(square)] = mask
labels = ['ranks', 'files', 'diagonals', 'antidiagonals']
if reverse: labels = ['reversed' + label.title() for label in labels]
return {label: masks for label, masks in zip(labels, maskDicts)}
def create_mask(*squareNotationList):
return Bitboard(*map(parse_notation, squareNotationList))
def generate_center_file_masks():
fileMasks = generate_ray_masks()['files']
return fileMasks[Bitboard(3)], fileMasks[Bitboard(4)]
def create_blocker(square, direction):
x, y = get_coordinate(square)
blockerSquare = get_square(x, y + direction)
return Bitboard(blockerSquare) if 0 <= blockerSquare < 64 else 0
def generate_reversed_square_masks():
reversedSquares = {}
for square in range(64):
squareBitboard = Bitboard(square)
reversedSquares[squareBitboard] = reverse_bitboard(squareBitboard)
return reversedSquares
def movesets(self): bitboards = [Bitboard(*squares) for squares in self.endSquareSets] return bitboards[0] if len(self.endSquareSets) == 1 else bitboards
def moves(self): allSquares = sum(self.endSquareSets, []) return [Bitboard(square) for square in allSquares]
def key(self): return Bitboard(self.startSquare)