diff --git a/src/eval-simple.c-move-to-temp-migration-bitboard__eval-simple.c b/src/eval-simple.c-move-to-temp-migration-bitboard__eval-simple.c new file mode 100644 index 0000000..a56d599 --- /dev/null +++ b/src/eval-simple.c-move-to-temp-migration-bitboard__eval-simple.c @@ -0,0 +1,199 @@ +/* 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 "br.h" +#include "debug.h" + +#include "piece.h" +#include "eval-simple.h" +#include "position.h" + +/* + * Tables are from https://www.chessprogramming.org/Simplified_Evaluation_Function + * + * Attention! Tables are black point of view (to be visually easier to read). + */ + +static int mg_pawn[] = { + 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 +}; + +static int mg_knight[] = { + -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 +}; + +static int mg_bishop[] = { + -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 +}; + +static int mg_rook[] = { + 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 +}; + +static int mg_queen[] = { + -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 +}; + +static int mg_king[] = { + -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 +}; + +static int eg_king[] = { + -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 +}; + +/* as pieces bitboard tables start at position 2; we make these tables + * bigger. + */ +static int *mg_tables[] = { + NULL, + NULL, + mg_pawn, + mg_knight, + mg_bishop, + mg_rook, + mg_queen, + mg_king +}; + +static int *eg_tables[] = { + NULL, + NULL, + mg_pawn, + mg_knight, + mg_bishop, + mg_rook, + mg_queen, + eg_king +}; + +/* to flip vertically a square, we need to XOR it with 56 + */ +static int mg_table[2][6 + 2][64]; +static int eg_table[2][6 + 2][64]; + +void eval_simple_init(void) +{ +# ifdef DEBUG_EVAL + log_f(1, "initializing piece tables\n"); +# endif + for (int piece = BB_PAWN; piece <= BB_KING; ++piece) { + for (int square = 0; square < 64; ++square) { + mg_table[WHITE][piece][square] = mg_tables[piece][FLIP_V(square)]; + eg_table[WHITE][piece][square] = eg_tables[piece][FLIP_V(square)]; + mg_table[BLACK][piece][square] = mg_tables[piece][square]; + eg_table[BLACK][piece][square] = eg_tables[piece][square]; + } + } +} + +/** + * 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 increntally when doing moves. + * + * @return: the @pos evaluation in centipawns + */ +eval_t eval_simple(pos_t *pos) +{ + eval_t eval[2] = { 0, 0 }; + int eg = simple_is_endgame(pos); + int (*gg)[6 + 2][64]= eg? eg_table: mg_table; + + pos->eval_simple_phase = ENDGAME; +# ifdef DEBUG_EVAL + log_f(5, "phase = %s.\n", eg? "endgame": "midgame"); +# endif + + for (int color = WHITE; color <= BLACK; ++color) { + for (uint piece = PAWN; piece <= KING; piece <<= 1) { + int bb = PIECETOBB(piece), cur; + u64 _t; + +# ifdef DEBUG_EVAL + log_f(5, "p=%u bb=%d %s %s: count=%d val=%ld ", piece, bb, color? "black": "white", + P_SYM(piece), popcount64(pos->bb[color][bb]), + popcount64(pos->bb[color][bb]) * P_VALUE(piece)); +# endif + + eval[color] += popcount64(pos->bb[color][bb]) * P_LETTER(piece); + bit_for_each64(cur, _t, pos->bb[color][bb]) { +# ifdef DEBUG_EVAL + log(5, "sq=%d:%d ", cur, gg[color][bb][cur]); +# endif + eval[color] += gg[color][bb][cur]; + } +# ifdef DEBUG_EVAL + log(5, "\n"); +# endif + } + } +# ifdef DEBUG_EVAL + log_f(2, "eval:%d white:%d black:%d\n", eval[WHITE] - eval[BLACK], + eval[WHITE], eval[BLACK]); +# endif + + return eval[WHITE] - eval[BLACK]; +}