40 lines
1 KiB
Python
40 lines
1 KiB
Python
|
#!/usr/bin/env python3
|
||
|
|
"""Pre-compute pawn captures bitboards for each square."""
|
||
|
|
|
||
|
|
TEMPLATE = """\
|
||
|
|
/// Pre-computed pawn captures.
|
||
|
|
pub const PAWN_CAPTURES: [[Bitboard; 64]; 2] = [
|
||
|
|
[
|
||
|
|
{}
|
||
|
|
],
|
||
|
|
[
|
||
|
|
{}
|
||
|
|
],
|
||
|
|
];
|
||
|
|
"""
|
||
|
|
|
||
|
|
def bit_pos(square):
|
||
|
|
return 1 << square
|
||
|
|
|
||
|
|
def get_captures():
|
||
|
|
both_captures = []
|
||
|
|
for direction in [1, -1]:
|
||
|
|
captures = []
|
||
|
|
for f in range(8):
|
||
|
|
for r in range(8):
|
||
|
|
bitboard = 0
|
||
|
|
prog_r = r + direction
|
||
|
|
if 0 < prog_r < 7:
|
||
|
|
prev_f = f - 1
|
||
|
|
if prev_f >= 0:
|
||
|
|
bitboard |= bit_pos(prev_f * 8 + prog_r)
|
||
|
|
next_f = f + 1
|
||
|
|
if next_f <= 7:
|
||
|
|
bitboard |= bit_pos(next_f * 8 + prog_r)
|
||
|
|
captures.append(" 0b{:064b},".format(bitboard))
|
||
|
|
both_captures.append(captures)
|
||
|
|
return both_captures
|
||
|
|
|
||
|
|
CAPTURES = get_captures()
|
||
|
|
print(TEMPLATE.format("\n".join(CAPTURES[0]), "\n".join(CAPTURES[1])))
|