stellar

UCI Chess engine written in C++20
git clone git://git.dimitrijedobrota.com/stellar.git
Log | Files | Refs | README | LICENSE |
commit311aab31f8f60a6b274b50c3e26e7ad2208c3675
parentb1e0eabe0aa23b9f0a858437535b4f2199cceb66
authorDimitrije Dobrota <mail@dimitrijedobrota.com>
dateTue, 8 Aug 2023 10:39:02 +0200

Improve Node Counting

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

2 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt

@@ -3,7 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

project(
Stellar
VERSION 0.0.16
VERSION 0.0.17
DESCRIPTION "Chess engine written in C"
HOMEPAGE_URL https://git.dimitrijedobrota.com/stellar.git
LANGUAGES C

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

@@ -145,19 +145,20 @@ int quiescence(Stats *stats, const Board *board, int alpha, int beta) {

return alpha;
}
int is_repetition() { return 0; }
int negamax(Stats *stats, const Board *board, int alpha, int beta, int depth) {
HasheFlag flag = flagAlpha;
U64 bhash = board_hash(board);
HasheFlag flag = flagAlpha;
stats->pv_length[stats->ply] = stats->ply;
if (stats->ply && is_repetition()) return 0;
int pv_node = (beta - alpha) > 1;
int score =
ttable_read(stats->ttable, bhash, alpha, beta, depth, stats->ply);
if (stats->ply && score != TTABLE_UNKNOWN && !pv_node) return score;
stats->nodes++;
stats->pv_length[stats->ply] = stats->ply;
if (depth == 0) {
int score = quiescence(stats, board, alpha, beta);
ttable_write(stats->ttable, bhash, score, depth, stats->ply, flagExact);

@@ -169,6 +170,7 @@ int negamax(Stats *stats, const Board *board, int alpha, int beta, int depth) {

if (alpha >= beta) return alpha;
if (stats->ply > MAX_PLY - 1) return evaluate(board);
stats->nodes++;
int isCheck = board_isCheck(board);
if (isCheck) depth++;

@@ -189,15 +191,13 @@ int negamax(Stats *stats, const Board *board, int alpha, int beta, int depth) {

MoveList list;
move_list_generate(&list, board);
if (stats->follow_pv) enable_pv_scoring(stats, &list);
move_list_sort(stats, &list);
int legal_moves = 0;
int searched = 0;
for (int i = 0; i < move_list_size(&list); i++) {
Move move = move_list_move(&list, i);
const Move move = move_list_move(&list, i);
board_copy(board, &copy);
if (move_make(move, &copy, 0) == 0) continue;

@@ -211,8 +211,7 @@ int negamax(Stats *stats, const Board *board, int alpha, int beta, int depth) {

} else {
// Late Move Reduction
if (searched >= FULL_DEPTH && depth >= REDUCTION_LIMIT &&
!isCheck && !board_isCheck(&copy) && !move_capture(move) &&
!move_promote(move)) {
!isCheck && !move_capture(move) && !move_promote(move)) {
score = -negamax(stats, &copy, -alpha - 1, -alpha, depth - 2);
} else
score = alpha + 1;

@@ -294,23 +293,24 @@ void search_position(const Board *board, int depth) {

alpha = score - WINDOW;
beta = score + WINDOW;
if (score > -MATE_VALUE && score < -MATE_SCORE) {
printf("info score mate %d depth %d nodes %ld pv ",
-(score + MATE_VALUE) / 2 - 1, crnt, stats.nodes);
} else if (score > MATE_SCORE && score < MATE_VALUE) {
printf("info score mate %d depth %d nodes %ld pv ",
(MATE_VALUE - score) / 2 + 1, crnt, stats.nodes);
} else {
printf("info score cp %d depth %d nodes %ld pv ", score, crnt,
stats.nodes);
}
if (stats.pv_length[0]) {
if (score > -MATE_VALUE && score < -MATE_SCORE) {
printf("info score mate %d depth %d nodes %ld pv ",
-(score + MATE_VALUE) / 2 - 1, crnt, stats.nodes);
} else if (score > MATE_SCORE && score < MATE_VALUE) {
printf("info score mate %d depth %d nodes %ld pv ",
(MATE_VALUE - score) / 2 + 1, crnt, stats.nodes);
} else {
printf("info score cp %d depth %d nodes %ld pv ", score, crnt,
stats.nodes);
}
for (int i = 0; i < stats.pv_length[0]; i++) {
move_print_UCI(stats.pv_table[0][i]);
printf(" ");
for (int i = 0; i < stats.pv_length[0]; i++) {
move_print_UCI(stats.pv_table[0][i]);
printf(" ");
}
printf("\n");
}
printf("\n");
crnt++;
}