stellar

UCI Chess engine written in C++20
git clone git://git.dimitrijedobrota.com/stellar.git
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commitb6be584c1ee1da0b25461b87a4e1364554284f96
parente26c0125387c4738632abdde53da5266823d04c1
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateMon, 19 Sep 2022 19:28:29 +0200

Further refactor Bishop and Rook Attack functions

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

1 files changed, 31 insertions(+), 47 deletions(-)

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

@@ -170,67 +170,51 @@ U64 mask_king_attacks(int square) {

return attacks;
}
U64 mask_bishop_attacks(int square) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
direction_f dir[4] = {noEaOne, noWeOne, soEaOne, soWeOne};
int tr = square / 8, tf = square % 8, i, j;
int len[4] = {MIN(7 - tf, 7 - tr) - 1, MIN(tf, 7 - tr) - 1,
MIN(7 - tf, tr) - 1, MIN(tf, tr) - 1};
U64 mask_slide_attacks(int square, U64 block, direction_f dir[4], int len[4]) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
int i, j;
bit_set(bitboard, square);
for (i = 0; i < 4; i++)
for (j = 0, tmp = bitboard; j < len[i]; j++)
attacks |= tmp = dir[i](tmp);
for (i = 0; i < 4; i++) {
for (j = 0, tmp = bitboard; j < len[i]; j++) {
attacks |= tmp = (dir[i])(tmp);
if (tmp & block)
break;
}
}
return attacks;
}
U64 mask_rook_attacks(int square) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
direction_f dir[4] = {westOne, soutOne, eastOne, nortOne};
int tr = square / 8, tf = square % 8, i, j;
int len[4] = {tf - 1, tr - 1, 6 - tf, 6 - tr};
direction_f bishop_direction[4] = {noEaOne, noWeOne, soEaOne, soWeOne};
direction_f rook_direction[4] = {westOne, soutOne, eastOne, nortOne};
bit_set(bitboard, square);
for (i = 0; i < 4; i++)
for (j = 0, tmp = bitboard; j < len[i]; j++)
attacks |= tmp = dir[i](tmp);
U64 mask_bishop_attacks(int square) {
int tr = square / 8, tf = square % 8;
int len[4] = {MIN(7 - tf, 7 - tr) - 1, MIN(tf, 7 - tr) - 1,
MIN(7 - tf, tr) - 1, MIN(tf, tr) - 1};
return mask_slide_attacks(square, C64(0), bishop_direction, len);
}
return attacks;
U64 mask_rook_attacks(int square) {
int tr = square / 8, tf = square % 8;
int len[4] = {tf - 1, tr - 1, 6 - tf, 6 - tr};
return mask_slide_attacks(square, C64(0), rook_direction, len);
}
U64 bishop_attacks_on_the_fly(int square, U64 block) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
direction_f dir[4] = {noEaOne, noWeOne, soEaOne, soWeOne};
int tr = square / 8, tf = square % 8, i, j;
int len[4] = {MIN(7 - tf, 7 - tr), MIN(tf, 7 - tr), MIN(7 - tf, tr),
MIN(tf, tr)};
int tr = square / 8, tf = square % 8;
int len[4] = {MIN(7 - tf, 7 - tr), MIN(tf, 7 - tr), MIN(7 - tf, tr),
MIN(tf, tr)};
bit_set(bitboard, square);
for (i = 0; i < 4; i++) {
for (j = 0, tmp = bitboard; j < len[i]; j++) {
attacks |= tmp = dir[i](tmp);
if (tmp & block)
break;
}
}
return attacks;
return mask_slide_attacks(square, block, bishop_direction, len);
}
U64 rook_attacks_on_the_fly(int square, U64 block) {
U64 bitboard = C64(0), attacks = C64(0), tmp;
direction_f dir[4] = {westOne, soutOne, eastOne, nortOne};
int tr = square / 8, tf = square % 8, i, j;
int len[4] = {tf, tr, 7 - tf, 7 - tr};
int tr = square / 8, tf = square % 8;
int len[4] = {tf, tr, 7 - tf, 7 - tr};
bit_set(bitboard, square);
for (i = 0; i < 4; i++) {
for (j = 0, tmp = bitboard; j < len[i]; j++) {
attacks |= tmp = dir[i](tmp);
if (tmp & block)
break;
}
}
return attacks;
return mask_slide_attacks(square, block, rook_direction, len);
}
void init_leapers_attacks(void) {

@@ -252,6 +236,6 @@ int main(void) {

bit_set(block, d5);
for (int square = 0; square < 64; square++)
bitboard_print(mask_rook_attacks(square));
bitboard_print(mask_bishop_attacks(square));
return 0;
}