Files
Knightly/engine/src/bitboard/movegen/kings.rs

88 lines
2.8 KiB
Rust

use super::*;
impl Board {
pub fn add_king_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
let piece_index = 5 + self.side_to_move * 6;
let mut kings = self.bitboards[piece_index as usize];
let empty = !self.occupancy[2];
let opponents = self.occupancy[1 - self.side_to_move as usize];
while kings != 0 {
let from_sq = pop_lsb(&mut kings);
let move_map = self.get_pseudo_king_moves(from_sq) & move_mask;
let mut quiet_map = move_map & empty;
let mut capture_map = move_map & opponents;
while quiet_map != 0 {
let to_sq = pop_lsb(&mut quiet_map);
quiet_buffer.add(BitMove::quiet(
from_sq as u8,
to_sq as u8,
None
));
}
while capture_map != 0 {
let to_sq = pop_lsb(&mut capture_map);
capture_buffer.add(BitMove::capture(
from_sq as u8,
to_sq as u8,
None
));
}
}
}
pub fn add_king_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
let offset = 6 * self.side_to_move as usize;
let mut kings: u64 = self.bitboards[5 + offset];
let opponents = self.occupancy[1 - self.side_to_move as usize];
while kings != 0 {
let next_sq: u32 = pop_lsb(&mut kings);
let mut attacks: u64 = self.get_pseudo_king_moves(next_sq) & opponents & move_mask;
attacks = self.get_pin_masked_moves(attacks, next_sq);
while attacks != 0 {
let to_sq = pop_lsb(&mut attacks);
buffer.add(BitMove::capture(
next_sq as u8,
to_sq as u8,
None
));
}
}
}
pub fn add_king_castles(&self, buffer: &mut MoveBuffer, move_mask: u64) {
if self.castling_rights & (0b11 << (2 - 2 * self.side_to_move)) == 0 {
return;
}
let offset = 5 + 6 * self.side_to_move as u8;
let castle_offset = 2 - 2 * self.side_to_move as u8;
let castling_rights = self.castling_rights & 3 << castle_offset;
let occupied = self.occupancy[2];
let king_sq = self.bitboards[offset as usize].trailing_zeros();
let queenside_mask = 0b111 << (king_sq - 3);
let kingside_mask = 0b11 << (king_sq + 1);
if (castling_rights & 1 << castle_offset) != 0
&& queenside_mask & occupied == 0
&& !move_mask & 0b11 << (king_sq - 2) == 0
&& !self.is_square_attacked(king_sq - 2) {
buffer.add(BitMove::castle(
king_sq as u8,
(king_sq - 2) as u8
));
}
if (castling_rights & 2 << castle_offset) != 0
&& kingside_mask & occupied == 0
&& !move_mask & 0b11 << (king_sq + 1) == 0
&& !self.is_square_attacked(king_sq + 2) {
buffer.add(BitMove::castle(
king_sq as u8,
(king_sq + 2) as u8
));
}
}
}