stellar

UCI Chess engine written in C++20
git clone git://git.dimitrijedobrota.com/stellar.git
Log | Files | Refs | README | LICENSE |
commit03fbb7cf3cd5a47ba4caf020c6d8752d190294a8
parenta329d919aec6b3ea7b12925a5cba310b5bd7613b
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateMon, 19 Sep 2022 18:44:49 +0200

Bishop and Rook attack on the fly

Diffstat:
Msrc/engine.c|+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++--

1 files changed, 69 insertions(+), 2 deletions(-)

diff --git a/src/engine.c b/src/engine.c

@@ -169,7 +169,7 @@ U64 mask_king_attacks(int square) {

return attacks;
}
U64 mask_bishup_attacks(int square) {
U64 mask_bishop_attacks(int square) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
int tr = square / 8, tf = square % 8, i;

@@ -205,6 +205,66 @@ U64 mask_rook_attacks(int square) {

return attacks;
}
U64 bishop_attacks_on_the_fly(int square, U64 block) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
int tr = square / 8, tf = square % 8, i;
bit_set(bitboard, square);
for (i = 0, tmp = bitboard; i < MIN(7 - tf, 7 - tr); i++) {
attacks |= tmp = noEaOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < MIN(tf, 7 - tr); i++) {
attacks |= tmp = noWeOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < MIN(7 - tf, tr); i++) {
attacks |= tmp = soEaOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < MIN(tf, tr); i++) {
attacks |= tmp = soWeOne(tmp);
if (tmp & block)
break;
}
return attacks;
}
U64 rook_attacks_on_the_fly(int square, U64 block) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
int tr = square / 8, tf = square % 8, i;
bit_set(bitboard, square);
for (i = 0, tmp = bitboard; i < tf; i++) {
attacks |= tmp = westOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < tr; i++) {
attacks |= tmp = soutOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < 7; i++) {
attacks |= tmp = eastOne(tmp);
if (tmp & block)
break;
}
for (i = 0, tmp = bitboard; i < 7; i++) {
attacks |= tmp = nortOne(tmp);
if (tmp & block)
break;
}
return attacks;
}
void init_leapers_attacks(void) {
for (int square = 0; square < 64; square++) {
pawn_attacks[WHITE][square] = mask_pawn_attacks(WHITE, square);

@@ -216,7 +276,14 @@ void init_leapers_attacks(void) {

int main(void) {
init_leapers_attacks();
U64 block = C64(0);
bit_set(block, e4);
bit_set(block, e5);
bit_set(block, d4);
bit_set(block, d5);
for (int square = 0; square < 64; square++)
bitboard_print(mask_rook_attacks(square));
bitboard_print(rook_attacks_on_the_fly(square, block));
return 0;
}