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add uci support

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srtk 2025-07-04 17:12:35 +05:30
parent e7af512d93
commit d649358c12
13 changed files with 618 additions and 127 deletions
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31
src/evaluation.c
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@ -1,5 +1,6 @@
#include "evaluation.h"
#include "movegen.h"
#include "repetition.h"
// Material values
const int piece_value[12] = {100, 320, 330, 500, 900, 20000,
@ -197,6 +198,22 @@ int evaluate_position(const GameState *state) {
score -= pst_king_mid[63 - sq];
}
// Add randomness to break symmetry in equal positions
score += (int)(hash_position(state) % 10) - 5;
// Encourage piece activity
int white_pieces = __builtin_popcountll(state->occ_white);
int black_pieces = __builtin_popcountll(state->occ_black);
// Slight bonus for having pieces in the center
U64 center = 0x0000001818000000ULL; // e4, e5, d4, d5
U64 extended_center = 0x00003C3C3C3C0000ULL; // c3-f3 to c6-f6
score += __builtin_popcountll(state->occ_white & center) * 5;
score -= __builtin_popcountll(state->occ_black & center) * 5;
score += __builtin_popcountll(state->occ_white & extended_center) * 2;
score -= __builtin_popcountll(state->occ_black & extended_center) * 2;
return score;
}
@ -204,9 +221,21 @@ int evaluate_position(const GameState *state) {
int evaluate(const GameState *state) {
int score = evaluate_material(state) + evaluate_position(state);
// Mobility bonus (simplified)
// Mobility bonus
GameState temp_state = *state;
Move moves[256];
// Add repetition penalty to avoid draw by repetition everytime
U64 current_hash = hash_position(state);
for (int i = 0; i < state->history.position_count; i++) {
if (state->history.positions[i].hash == current_hash) {
if (state->history.positions[i].count >= 2) {
score -= 50; // Penalty for positions appearing twice
}
break;
}
}
temp_state.side_to_move = 0; // White
int white_mobility = generate_moves(&temp_state, moves);