/* eval-simple.c - simple position evaluation. * * Copyright (C) 2023 Bruno Raoult ("br") * Licensed under the GNU General Public License v3.0 or later. * Some rights reserved. See COPYING. * * You should have received a copy of the GNU General Public License along with this * program. If not, see . * * SPDX-License-Identifier: GPL-3.0-or-later * */ #include #include #include "chessdefs.h" #include "piece.h" #include "position.h" #include "eval-simple.h" #include "eval.h" /* * Piece-square tables. For easier reading, they are defined for black side: * * { * A8 .... H8 * .......... * .......... * A1 .... H1 * } */ const struct pc_sq pc_sq_def[] = { { /* * rofchade: * https://www.talkchess.com/forum3/viewtopic.php?f=2&t=68311&start=19 */ "rofchade", { [PAWN] = { { /* midgame */ 0, 0, 0, 0, 0, 0, 0, 0, 98, 134, 61, 95, 68, 126, 34, -11, -6, 7, 26, 31, 65, 56, 25, -20, -14, 13, 6, 21, 23, 12, 17, -23, -27, -2, -5, 12, 17, 6, 10, -25, -26, -4, -4, -10, 3, 3, 33, -12, -35, -1, -20, -23, -15, 24, 38, -22, 0, 0, 0, 0, 0, 0, 0, 0, }, { /* endgame */ 0, 0, 0, 0, 0, 0, 0, 0, 178, 173, 158, 134, 147, 132, 165, 187, 94, 100, 85, 67, 56, 53, 82, 84, 32, 24, 13, 5, -2, 4, 17, 17, 13, 9, -3, -7, -7, -8, 3, -1, 4, 7, -6, 1, 0, -5, -1, -8, 13, 8, 8, 10, 13, 0, 2, -7, 0, 0, 0, 0, 0, 0, 0, 0, } }, [KNIGHT] = { { /* midgame */ -167, -89, -34, -49, 61, -97, -15, -107, -73, -41, 72, 36, 23, 62, 7, -17, -47, 60, 37, 65, 84, 129, 73, 44, -9, 17, 19, 53, 37, 69, 18, 22, -13, 4, 16, 13, 28, 19, 21, -8, -23, -9, 12, 10, 19, 17, 25, -16, -29, -53, -12, -3, -1, 18, -14, -19, -105, -21, -58, -33, -17, -28, -19, -23, }, { /* endgame */ -58, -38, -13, -28, -31, -27, -63, -99, -25, -8, -25, -2, -9, -25, -24, -52, -24, -20, 10, 9, -1, -9, -19, -41, -17, 3, 22, 22, 22, 11, 8, -18, -18, -6, 16, 25, 16, 17, 4, -18, -23, -3, -1, 15, 10, -3, -20, -22, -42, -20, -10, -5, -2, -20, -23, -44, -29, -51, -23, -15, -22, -18, -50, -64, } }, [BISHOP] = { { /* midgame */ -29, 4, -82, -37, -25, -42, 7, -8, -26, 16, -18, -13, 30, 59, 18, -47, -16, 37, 43, 40, 35, 50, 37, -2, -4, 5, 19, 50, 37, 37, 7, -2, -6, 13, 13, 26, 34, 12, 10, 4, 0, 15, 15, 15, 14, 27, 18, 10, 4, 15, 16, 0, 7, 21, 33, 1, -33, -3, -14, -21, -13, -12, -39, -21, }, { /* endgame */ -14, -21, -11, -8, -7, -9, -17, -24, -8, -4, 7, -12, -3, -13, -4, -14, 2, -8, 0, -1, -2, 6, 0, 4, -3, 9, 12, 9, 14, 10, 3, 2, -6, 3, 13, 19, 7, 10, -3, -9, -12, -3, 8, 10, 13, 3, -7, -15, -14, -18, -7, -1, 4, -9, -15, -27, -23, -9, -23, -5, -9, -16, -5, -17, }, }, [ROOK] = { { /* midgame */ 32, 42, 32, 51, 63, 9, 31, 43, 27, 32, 58, 62, 80, 67, 26, 44, -5, 19, 26, 36, 17, 45, 61, 16, -24, -11, 7, 26, 24, 35, -8, -20, -36, -26, -12, -1, 9, -7, 6, -23, -45, -25, -16, -17, 3, 0, -5, -33, -44, -16, -20, -9, -1, 11, -6, -71, -19, -13, 1, 17, 16, 7, -37, -26, }, { /* endgame */ 13, 10, 18, 15, 12, 12, 8, 5, 11, 13, 13, 11, -3, 3, 8, 3, 7, 7, 7, 5, 4, -3, -5, -3, 4, 3, 13, 1, 2, 1, -1, 2, 3, 5, 8, 4, -5, -6, -8, -11, -4, 0, -5, -1, -7, -12, -8, -16, -6, -6, 0, 2, -9, -9, -11, -3, -9, 2, 3, -1, -5, -13, 4, -20, }, }, [QUEEN] = { { /* midgame */ -28, 0, 29, 12, 59, 44, 43, 45, -24, -39, -5, 1, -16, 57, 28, 54, -13, -17, 7, 8, 29, 56, 47, 57, -27, -27, -16, -16, -1, 17, -2, 1, -9, -26, -9, -10, -2, -4, 3, -3, -14, 2, -11, -2, -5, 2, 14, 5, -35, -8, 11, 2, 8, 15, -3, 1, -1, -18, -9, 10, -15, -25, -31, -50, }, { /* endgame */ -9, 22, 22, 27, 27, 19, 10, 20, -17, 20, 32, 41, 58, 25, 30, 0, -20, 6, 9, 49, 47, 35, 19, 9, 3, 22, 24, 45, 57, 40, 57, 36, -18, 28, 19, 47, 31, 34, 39, 23, -16, -27, 15, 6, 9, 17, 10, 5, -22, -23, -30, -16, -16, -23, -36, -32, -33, -28, -22, -43, -5, -32, -20, -41, }, }, [KING] = { /* midgame */ { -65, 23, 16, -15, -56, -34, 2, 13, 29, -1, -20, -7, -8, -4, -38, -29, -9, 24, 2, -16, -20, 6, 22, -22, -17, -20, -12, -27, -30, -25, -14, -36, -49, -1, -27, -39, -46, -44, -33, -51, -14, -14, -22, -46, -44, -30, -15, -27, 1, 7, -8, -64, -43, -16, 9, 8, -15, 36, 12, -54, 8, -28, 24, 14, }, { /* endgame */ -74, -35, -18, -18, -11, 15, 4, -17, -12, 17, 14, 17, 17, 38, 23, 11, 10, 17, 23, 15, 20, 45, 44, 13, -8, 22, 24, 27, 26, 33, 26, 3, -18, -4, 21, 24, 27, 23, 9, -11, -19, -3, 11, 21, 23, 16, 7, -9, -27, -11, 4, 13, 14, 4, -5, -17, -53, -34, -21, -11, -28, -14, -24, -43 } } } }, /* CPW */ { /* * CPW: * https://www.chessprogramming.org/Simplified_Evaluation_Function * Note: ≠ https://github.com/nescitus/cpw-engine */ "cpw", { [PAWN] = { { /* midgame */ 0, 0, 0, 0, 0, 0, 0, 0, 50, 50, 50, 50, 50, 50, 50, 50, 10, 10, 20, 30, 30, 20, 10, 10, 5, 5, 10, 25, 25, 10, 5, 5, 0, 0, 0, 20, 20, 0, 0, 0, 5, -5, -10, 0, 0, -10, -5, 5, 5, 10, 10, -20, -20, 10, 10, 5, 0, 0, 0, 0, 0, 0, 0, 0, }, { /* endgame */ 0, 0, 0, 0, 0, 0, 0, 0, 50, 50, 50, 50, 50, 50, 50, 50, 10, 10, 20, 30, 30, 20, 10, 10, 5, 5, 10, 25, 25, 10, 5, 5, 0, 0, 0, 20, 20, 0, 0, 0, 5, -5, -10, 0, 0, -10, -5, 5, 5, 10, 10, -20, -20, 10, 10, 5, 0, 0, 0, 0, 0, 0, 0, 0, }, }, [KNIGHT] = { { /* midgame */ -50, -40, -30, -30, -30, -30, -40, -50, -40, -20, 0, 0, 0, 0, -20, -40, -30, 0, 10, 15, 15, 10, 0, -30, -30, 5, 15, 20, 20, 15, 5, -30, -30, 0, 15, 20, 20, 15, 0, -30, -30, 5, 10, 15, 15, 10, 5, -30, -40, -20, 0, 5, 5, 0, -20, -40, -50, -40, -30, -30, -30, -30, -40, -50 }, { /* endgame */ -50, -40, -30, -30, -30, -30, -40, -50, -40, -20, 0, 0, 0, 0, -20, -40, -30, 0, 10, 15, 15, 10, 0, -30, -30, 5, 15, 20, 20, 15, 5, -30, -30, 0, 15, 20, 20, 15, 0, -30, -30, 5, 10, 15, 15, 10, 5, -30, -40, -20, 0, 5, 5, 0, -20, -40, -50, -40, -30, -30, -30, -30, -40, -50 }, }, [BISHOP] = { { /* midgame */ -20, -10, -10, -10, -10, -10, -10, -20, -10, 0, 0, 0, 0, 0, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 5, 5, 10, 10, 5, 5, -10, -10, 0, 10, 10, 10, 10, 0, -10, -10, 10, 10, 10, 10, 10, 10, -10, -10, 5, 0, 0, 0, 0, 5, -10, -20, -10, -10, -10, -10, -10, -10, -20, }, { /* endgame */ -20, -10, -10, -10, -10, -10, -10, -20, -10, 0, 0, 0, 0, 0, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 5, 5, 10, 10, 5, 5, -10, -10, 0, 10, 10, 10, 10, 0, -10, -10, 10, 10, 10, 10, 10, 10, -10, -10, 5, 0, 0, 0, 0, 5, -10, -20, -10, -10, -10, -10, -10, -10, -20, }, }, [ROOK] = { { /* midgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 10, 10, 10, 10, 10, 5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, 0, 0, 0, 5, 5, 0, 0, 0, }, { /* endgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 10, 10, 10, 10, 10, 5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, 0, 0, 0, 5, 5, 0, 0, 0, }, }, [QUEEN] = { { /* midgame */ -20, -10, -10, -5, -5, -10, -10, -20, -10, 0, 0, 0, 0, 0, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -5, 0, 5, 5, 5, 5, 0, -5, 0, 0, 5, 5, 5, 5, 0, -5, -10, 5, 5, 5, 5, 5, 0, -10, -10, 0, 5, 0, 0, 0, 0, -10, -20, -10, -10, -5, -5, -10, -10, -20, }, { /* endgame */ -20, -10, -10, -5, -5, -10, -10, -20, -10, 0, 0, 0, 0, 0, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -5, 0, 5, 5, 5, 5, 0, -5, 0, 0, 5, 5, 5, 5, 0, -5, -10, 5, 5, 5, 5, 5, 0, -10, -10, 0, 5, 0, 0, 0, 0, -10, -20, -10, -10, -5, -5, -10, -10, -20, }, }, [KING] = { /* midgame */ { -30, -40, -40, -50, -50, -40, -40, -30, -30, -40, -40, -50, -50, -40, -40, -30, -30, -40, -40, -50, -50, -40, -40, -30, -30, -40, -40, -50, -50, -40, -40, -30, -20, -30, -30, -40, -40, -30, -30, -20, -10, -20, -20, -20, -20, -20, -20, -10, 20, 20, 0, 0, 0, 0, 20, 20, 20, 30, 10, 0, 0, 10, 30, 20, }, { /* endgame */ -50, -40, -30, -20, -20, -30, -40, -50, -30, -20, -10, 0, 0, -10, -20, -30, -30, -10, 20, 30, 30, 20, -10, -30, -30, -10, 30, 40, 40, 30, -10, -30, -30, -10, 30, 40, 40, 30, -10, -30, -30, -10, 20, 30, 30, 20, -10, -30, -30, -30, 0, 0, 0, 0, -30, -30, -50, -30, -30, -30, -30, -30, -30, -50, } } } }, /* CPW */ { /* * sjeng: https://github.com/gcp/sjeng * Rook and Queen from CPW. */ "sjeng", { [PAWN] = { { /* midgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 15, 20, 20, 15, 10, 5, 4, 8, 12, 16, 16, 12, 8, 4, 3, 6, 9, 14, 14, 9, 6, 3, 2, 4, 6, 12, 12, 6, 4, 2, 1, 2, 3, 10, 10, 3, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, { /* endgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 15, 20, 20, 15, 10, 5, 4, 8, 12, 16, 16, 12, 8, 4, 3, 6, 9, 14, 14, 9, 6, 3, 2, 4, 6, 12, 12, 6, 4, 2, 1, 2, 3, 10, 10, 3, 2, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, }, }, [KNIGHT] = { { /* midgame */ -20, -10, -10, -10, -10, -10, -10, -20, -10, 0, 0, 3, 3, 0, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 0, 3, 3, 0, 0, -10, -20, -10, -10, -10, -10, -10, -10, -20, }, { /* endgame */ -20, -10, -10, -10, -10, -10, -10, -20, -10, 0, 0, 3, 3, 0, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 0, 5, 10, 10, 5, 0, -10, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 0, 3, 3, 0, 0, -10, -20, -10, -10, -10, -10, -10, -10, -20, }, }, [BISHOP] = { { /* midgame */ -2, -2, -2, -2, -2, -2, -2, -2, -2, 8, 5, 5, 5, 5, 8, -2, -2, 3, 3, 5, 5, 3, 3, -2, -2, 2, 5, 4, 4, 5, 2, -2, -2, 2, 5, 4, 4, 5, 2, -2, -2, 3, 3, 5, 5, 3, 3, -2, -2, 8, 5, 5, 5, 5, 8, -2, -2, -2, -2, -2, -2, -2, -2, -2, }, { /* endgame */ -2, -2, -2, -2, -2, -2, -2, -2, -2, 8, 5, 5, 5, 5, 8, -2, -2, 3, 3, 5, 5, 3, 3, -2, -2, 2, 5, 4, 4, 5, 2, -2, -2, 2, 5, 4, 4, 5, 2, -2, -2, 3, 3, 5, 5, 3, 3, -2, -2, 8, 5, 5, 5, 5, 8, -2, -2, -2, -2, -2, -2, -2, -2, -2, }, }, [ROOK] = { { /* midgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 10, 10, 10, 10, 10, 5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, 0, 0, 0, 5, 5, 0, 0, 0, }, { /* endgame */ 0, 0, 0, 0, 0, 0, 0, 0, 5, 10, 10, 10, 10, 10, 10, 5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, -5, 0, 0, 0, 0, 0, 0, -5, 0, 0, 0, 5, 5, 0, 0, 0, }, }, [QUEEN] = { { /* midgame */ -20, -10, -10, -5, -5, -10, -10, -20, -10, 0, 5, 0, 0, 0, 0, -10, -10, 5, 5, 5, 5, 5, 0, -10, 0, 0, 5, 5, 5, 5, 0, -5, -5, 0, 5, 5, 5, 5, 0, -5, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 0, 0, 0, 0, 0, -10, -20, -10, -10, -5, -5, -10, -10, -20, }, { /* endgame */ -20, -10, -10, -5, -5, -10, -10, -20, -10, 0, 5, 0, 0, 0, 0, -10, -10, 5, 5, 5, 5, 5, 0, -10, 0, 0, 5, 5, 5, 5, 0, -5, -5, 0, 5, 5, 5, 5, 0, -5, -10, 0, 5, 5, 5, 5, 0, -10, -10, 0, 0, 0, 0, 0, 0, -10, -20, -10, -10, -5, -5, -10, -10, -20, }, }, [KING] = { /* midgame */ { -55, -55, -89, -89, -89, -89, -55, -55, -34, -34, -55, -55, -55, -55, -34, -34, -21, -21, -34, -34, -34, -34, -21, -21, -13, -13, -21, -21, -21, -21, -13, -13, -8, -8, -13, -13, -13, -13, -8, -8, -5, -5, -8, -8, -8, -8, -5, -5, -3, -5, -6, -6, -6, -6, -5, -3, 2, 14, 0, 0, 0, 9, 14, 2, }, { /* endgame */ -5, -3, -1, 0, 0, -1, -3, -5, -3, 10, 10, 10, 10, 10, 10, -3, -1, 10, 25, 25, 25, 25, 10, -1, 0, 10, 25, 30, 30, 25, 10, 0, 0, 10, 25, 30, 30, 25, 10, 0, -1, 10, 25, 25, 25, 25, 10, -1, -3, 10, 10, 10, 10, 10, 10, -3, -5, -3, -1, 0, 0, -1, -3, -5, } } }, }, /* sjeng */ }; const int nb_pc_sq = ARRAY_SIZE(pc_sq_def); /* # of predefined pc_sq tables */ int pc_sq_current = 0; int pc_sq_mg[COLOR_NB][PT_NB][SQUARE_NB]; int pc_sq_eg[COLOR_NB][PT_NB][SQUARE_NB]; /* phase calculation from Fruit: * https://github.com/Warpten/Fruit-2.1 */ /** * calc_phase - calculate position phase * @pos: &position * * This function should be calculated when a new position is setup, or as * a verification of an incremental one. * phase is clamped between 0 (opening) and 24 (ending). * * @return: */ s16 calc_phase(pos_t *pos) { int phase = ALL_PHASE; phase -= P_PHASE * popcount64(pos->bb[WHITE][PAWN] | pos->bb[BLACK][PAWN]); phase -= N_PHASE * popcount64(pos->bb[WHITE][KNIGHT] | pos->bb[BLACK][KNIGHT]); phase -= B_PHASE * popcount64(pos->bb[WHITE][BISHOP] | pos->bb[BLACK][BISHOP]); phase -= R_PHASE * popcount64(pos->bb[WHITE][ROOK] | pos->bb[BLACK][ROOK]); phase -= Q_PHASE * popcount64(pos->bb[WHITE][QUEEN] | pos->bb[BLACK][QUEEN]); phase = clamp(phase, 0, ALL_PHASE); # ifdef DEBUG_EVAL printf("calc phase:%d\n", phase); # endif return phase; } int eval_simple_find(char *str) { for (int i = 0; i < nb_pc_sq; ++i) if (!strcmp(pc_sq_def[i].name, str)) return i; return -1; } void eval_simple_set(int set) { const struct pc_sq *cur = pc_sq_def + set; # ifdef DEBUG_EVAL printf("initializing piece-square tables %d\n", set); # endif pc_sq_current = set; for (piece_type_t pt = PAWN; pt < PT_NB; ++pt) { for (square_t sq = 0; sq < SQUARE_NB; ++sq) { pc_sq_mg[BLACK][pt][sq] = cur->val[MIDGAME][pt][sq]; pc_sq_mg[WHITE][pt][sq] = cur->val[MIDGAME][pt][FLIP_V(sq)]; pc_sq_eg[BLACK][pt][sq] = cur->val[ENDGAME][pt][sq]; pc_sq_eg[WHITE][pt][sq] = cur->val[ENDGAME][pt][FLIP_V(sq)]; } } } void eval_simple_init(char *set) { int n = eval_simple_find(set); # ifdef DEBUG_EVAL printf("initializing eval_simple with set=%s: found=%d\n", set, n); # endif if (n >= 0) pc_sq_current = n; eval_simple_set(pc_sq_current); } /** * eval_material() - eval position material * @pos: &position to evaluate * * Basic material evaluation. Only midgame value is used. * * @return: the @pos material evaluation in centipawns */ eval_t eval_material(pos_t *pos) { eval_t val[COLOR_NB] = { 0 }; for (piece_type_t pt = PAWN; pt < KING; ++pt) { eval_t pval = piece_midval(pt); val[WHITE] += popcount64(pos->bb[WHITE][pt]) * pval; val[BLACK] += popcount64(pos->bb[BLACK][pt]) * pval; } # ifdef DEBUG_EVAL printf("material: w:%d b:%d\n", val[WHITE], val[BLACK]); # endif return val[WHITE] - val[BLACK]; } /** * eval_simple() - simple and fast position evaluation * @pos: &position to evaluate * * This function is normally used only during initialization, * or when changing phase (middlegame <--> endgame), as the eval * will be done incrementally when doing moves. * * @return: the @pos evaluation in centipawns */ eval_t eval_simple(pos_t *pos) { eval_t eval[2] = { 0, 0 }; eval_t mg_eval[2], eg_eval[2]; //struct pc_sq = sq_ int (*gg)[6 + 2][64] = eg? pc_sq_eg: pc_sq_mg; //pos->eval_simple_phase = ENDGAME; for (color_t color = WHITE; color < COLOR_NB; ++color) { mg_eval[color] = 0; eg_eval[color] = 0; for (piece_type_t pt = PAWN; pt < KING; pt++) { bitboard_t bb = pos->bb[color][pt]; while (bb) { square_t sq = bb_next(&bb); mg_eval[color] += pc_sq_mg[color][pt][sq]; eg_eval[color] += pc_sq_eg[color][pt][sq]; } # ifdef DEBUG_EVAL printf("c=%d pt=%d mg=%d eg=%d\n", color, pt, mg_eval[color], eg_eval[color]); # endif } } # ifdef DEBUG_EVAL printf("phase:%d mg[WHITE]:%d mg[BLACK]:%d eg[WHITE]:%d eg[BLACK]:%d\n", pos->phase, mg_eval[WHITE], mg_eval[BLACK], eg_eval[WHITE], eg_eval[BLACK]); # endif return eval[WHITE] - eval[BLACK]; }