X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=23597231641f1215deff1b72d5d52f0776ee7bf0;hp=f4b7fb757dfc3c340ef03229e70dcabd3bdf93b1;hb=c97104e8540b72ee2c6c9c13d3773d2c0f9ec32f;hpb=f56af8e84db25c0d26fe762fbe171ec5518177bb diff --git a/src/evaluate.cpp b/src/evaluate.cpp index f4b7fb75..23597231 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -1,13 +1,14 @@ /* - Glaurung, a UCI chess playing engine. - Copyright (C) 2004-2008 Tord Romstad + Stockfish, a UCI chess playing engine derived from Glaurung 2.1 + Copyright (C) 2004-2008 Tord Romstad (Glaurung author) + Copyright (C) 2008 Marco Costalba - Glaurung is free software: you can redistribute it and/or modify + Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. - Glaurung is distributed in the hope that it will be useful, + Stockfish is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. @@ -51,6 +52,7 @@ namespace { int WeightPassedPawnsMidgame = 0x100; int WeightPassedPawnsEndgame = 0x100; int WeightKingSafety[2] = { 0x100, 0x100 }; + int WeightSpace; // Internal evaluation weights. These are applied on top of the evaluation // weights read from UCI parameters. The purpose is to be able to change @@ -62,7 +64,9 @@ namespace { const int WeightPawnStructureEndgameInternal = 0x100; const int WeightPassedPawnsMidgameInternal = 0x100; const int WeightPassedPawnsEndgameInternal = 0x100; - const int WeightKingSafetyInternal = 0x100; + const int WeightKingSafetyInternal = 0x110; + const int WeightKingOppSafetyInternal = 0x110; + const int WeightSpaceInternal = 0x30; // Visually better to define tables constants typedef Value V; @@ -201,6 +205,19 @@ namespace { ((1ULL << SQ_A8) | (1ULL << SQ_H8)) }; + // The SpaceMask[color] contains area of the board which is consdered by + // the space evaluation. In the middle game, each side is given a bonus + // based on how many squares inside this area are safe and available for + // friendly minor pieces. + const Bitboard SpaceMask[2] = { + (1ULL<= 0 && threadID < THREAD_MAX); - stm = pos.side_to_move(); + memset(&ei, 0, sizeof(EvalInfo)); // Initialize by reading the incrementally updated scores included in the - // position object (material + piece square tables): + // position object (material + piece square tables) ei.mgValue = pos.mg_value(); ei.egValue = pos.eg_value(); - // Probe the material hash table: + // Probe the material hash table ei.mi = MaterialTable[threadID]->get_material_info(pos); ei.mgValue += ei.mi->mg_value(); ei.egValue += ei.mi->eg_value(); - factor[WHITE] = ei.mi->scale_factor(pos, WHITE); - factor[BLACK] = ei.mi->scale_factor(pos, BLACK); - // If we have a specialized evaluation function for the current material - // configuration, call it and return: - if(ei.mi->specialized_eval_exists()) - return ei.mi->evaluate(pos); + // configuration, call it and return + if (ei.mi->specialized_eval_exists()) + return ei.mi->evaluate(pos); - phase = pos.game_phase(); + // After get_material_info() call that modifies them + ScaleFactor factor[2]; + factor[WHITE] = ei.mi->scale_factor(pos, WHITE); + factor[BLACK] = ei.mi->scale_factor(pos, BLACK); - // Probe the pawn hash table: + // Probe the pawn hash table ei.pi = PawnTable[threadID]->get_pawn_info(pos); ei.mgValue += apply_weight(ei.pi->mg_value(), WeightPawnStructureMidgame); ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame); - // Initialize king attack bitboards and king attack zones for both sides: - ei.attackedBy[WHITE][KING] = pos.king_attacks(pos.king_square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.king_attacks(pos.king_square(BLACK)); - ei.attackZone[WHITE] = - ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8); - ei.attackZone[BLACK] = - ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8); - - // Initialize pawn attack bitboards for both sides: - ei.attackedBy[WHITE][PAWN] = - ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB); - ei.attackCount[WHITE] += - count_1s_max_15(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2; - ei.attackedBy[BLACK][PAWN] = - ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB); - ei.attackCount[BLACK] += - count_1s_max_15(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2; - - // Evaluate pieces: - for(Color c = WHITE; c <= BLACK; c++) { - Bitboard b; + // Initialize king attack bitboards and king attack zones for both sides + ei.attackedBy[WHITE][KING] = pos.piece_attacks(pos.king_square(WHITE)); + ei.attackedBy[BLACK][KING] = pos.piece_attacks(pos.king_square(BLACK)); + ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8); + ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8); + // Initialize pawn attack bitboards for both sides + ei.attackedBy[WHITE][PAWN] = ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB); + ei.attackedBy[BLACK][PAWN] = ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB); + ei.kingAttackersCount[WHITE] = count_1s_max_15(ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING])/2; + ei.kingAttackersCount[BLACK] = count_1s_max_15(ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING])/2; + + // Evaluate pieces + for (Color c = WHITE; c <= BLACK; c++) + { // Knights - for(int i = 0; i < pos.knight_count(c); i++) { - s = pos.knight_list(c, i); - evaluate_knight(pos, s, c, ei); - } + for (int i = 0; i < pos.piece_count(c, KNIGHT); i++) + evaluate_knight(pos, pos.piece_list(c, KNIGHT, i), c, ei); // Bishops - for(int i = 0; i < pos.bishop_count(c); i++) { - s = pos.bishop_list(c, i); - evaluate_bishop(pos, s, c, ei); - } + for (int i = 0; i < pos.piece_count(c, BISHOP); i++) + evaluate_bishop(pos, pos.piece_list(c, BISHOP, i), c, ei); // Rooks - for(int i = 0; i < pos.rook_count(c); i++) { - s = pos.rook_list(c, i); - evaluate_rook(pos, s, c, ei); - } + for (int i = 0; i < pos.piece_count(c, ROOK); i++) + evaluate_rook(pos, pos.piece_list(c, ROOK, i), c, ei); // Queens - for(int i = 0; i < pos.queen_count(c); i++) { - s = pos.queen_list(c, i); - evaluate_queen(pos, s, c, ei); - } + for(int i = 0; i < pos.piece_count(c, QUEEN); i++) + evaluate_queen(pos, pos.piece_list(c, QUEEN, i), c, ei); - // Some special patterns: - - // Trapped bishops on a7/h7/a2/h2 - b = pos.bishops(c) & MaskA7H7[c]; - while(b) { - s = pop_1st_bit(&b); - evaluate_trapped_bishop_a7h7(pos, s, c, ei); + // Special pattern: trapped bishops on a7/h7/a2/h2 + Bitboard b = pos.bishops(c) & MaskA7H7[c]; + while (b) + { + Square s = pop_1st_bit(&b); + evaluate_trapped_bishop_a7h7(pos, s, c, ei); } - // Trapped bishops on a1/h1/a8/h8 in Chess960: - if(Chess960) { - b = pos.bishops(c) & MaskA1H1[c]; - while(b) { - s = pop_1st_bit(&b); - evaluate_trapped_bishop_a1h1(pos, s, c, ei); - } + // Special pattern: trapped bishops on a1/h1/a8/h8 in Chess960: + if (Chess960) + { + b = pos.bishops(c) & MaskA1H1[c]; + while (b) + { + Square s = pop_1st_bit(&b); + evaluate_trapped_bishop_a1h1(pos, s, c, ei); + } } - ei.attackedBy[c][0] = - ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT] - | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK] - | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING]; + // Sum up all attacked squares + ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT] + | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK] + | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING]; } // Kings. Kings are evaluated after all other pieces for both sides, // because we need complete attack information for all pieces when computing // the king safety evaluation. - for(Color c = WHITE; c <= BLACK; c++) { - s = pos.king_square(c); - evaluate_king(pos, s, c, ei); - } + for (Color c = WHITE; c <= BLACK; c++) + evaluate_king(pos, pos.king_square(c), c, ei); // Evaluate passed pawns. We evaluate passed pawns for both sides at once, // because we need to know which side promotes first in positions where // both sides have an unstoppable passed pawn. - if(ei.pi->passed_pawns()) - evaluate_passed_pawns(pos, ei); + if (ei.pi->passed_pawns()) + evaluate_passed_pawns(pos, ei); - // Middle-game specific evaluation terms - if(phase > PHASE_ENDGAME) { + Phase phase = pos.game_phase(); + // Middle-game specific evaluation terms + if (phase > PHASE_ENDGAME) + { // Pawn storms in positions with opposite castling. - if(square_file(pos.king_square(WHITE)) >= FILE_E && - square_file(pos.king_square(BLACK)) <= FILE_D) - ei.mgValue += - ei.pi->queenside_storm_value(WHITE) - - ei.pi->kingside_storm_value(BLACK); - else if(square_file(pos.king_square(WHITE)) <= FILE_D && - square_file(pos.king_square(BLACK)) >= FILE_E) - ei.mgValue += - ei.pi->kingside_storm_value(WHITE) - - ei.pi->queenside_storm_value(BLACK); + if ( square_file(pos.king_square(WHITE)) >= FILE_E + && square_file(pos.king_square(BLACK)) <= FILE_D) + + ei.mgValue += ei.pi->queenside_storm_value(WHITE) + - ei.pi->kingside_storm_value(BLACK); + + else if ( square_file(pos.king_square(WHITE)) <= FILE_D + && square_file(pos.king_square(BLACK)) >= FILE_E) + + ei.mgValue += ei.pi->kingside_storm_value(WHITE) + - ei.pi->queenside_storm_value(BLACK); + + // Evaluate space for both sides + if (ei.mi->space_weight() > 0) + { + evaluate_space(pos, WHITE, ei); + evaluate_space(pos, BLACK, ei); + } } // Mobility @@ -430,47 +436,41 @@ Value evaluate(const Position &pos, EvalInfo &ei, int threadID) { ei.egValue += apply_weight(ei.egMobility, WeightMobilityEndgame); // If we don't already have an unusual scale factor, check for opposite - // colored bishop endgames, and use a lower scale for those: - if(phase < PHASE_MIDGAME && pos.opposite_colored_bishops() - && ((factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0)) || - (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0)))) { - if(pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == - 2*BishopValueMidgame) { - // Only the two bishops - if(pos.pawn_count(WHITE) + pos.pawn_count(BLACK) == 1) { - // KBP vs KB with only a single pawn; almost certainly a draw. - if(factor[WHITE] == SCALE_FACTOR_NORMAL) - factor[WHITE] = ScaleFactor(8); - if(factor[BLACK] == SCALE_FACTOR_NORMAL) - factor[BLACK] = ScaleFactor(8); - } - else { - // At least two pawns - if(factor[WHITE] == SCALE_FACTOR_NORMAL) - factor[WHITE] = ScaleFactor(32); - if(factor[BLACK] == SCALE_FACTOR_NORMAL) - factor[BLACK] = ScaleFactor(32); + // colored bishop endgames, and use a lower scale for those + if ( phase < PHASE_MIDGAME + && pos.opposite_colored_bishops() + && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0)) + || (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0)))) + { + ScaleFactor sf; + + // Only the two bishops ? + if ( pos.non_pawn_material(WHITE) == BishopValueMidgame + && pos.non_pawn_material(BLACK) == BishopValueMidgame) + { + // Check for KBP vs KB with only a single pawn that is almost + // certainly a draw or at least two pawns. + bool one_pawn = (pos.piece_count(WHITE, PAWN) + pos.piece_count(BLACK, PAWN) == 1); + sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32); } - } - else { - // Endgame with opposite-colored bishops, but also other pieces. - // Still a bit drawish, but not as drawish as with only the two - // bishops. - if(factor[WHITE] == SCALE_FACTOR_NORMAL) - factor[WHITE] = ScaleFactor(50); - if(factor[BLACK] == SCALE_FACTOR_NORMAL) - factor[BLACK] = ScaleFactor(50); - } + else + // Endgame with opposite-colored bishops, but also other pieces. Still + // a bit drawish, but not as drawish as with only the two bishops. + sf = ScaleFactor(50); + + if (factor[WHITE] == SCALE_FACTOR_NORMAL) + factor[WHITE] = sf; + if (factor[BLACK] == SCALE_FACTOR_NORMAL) + factor[BLACK] = sf; } // Interpolate between the middle game and the endgame score, and - // return: - Value value = scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor); + // return + Color stm = pos.side_to_move(); + + Value v = Sign[stm] * scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor); - if(ei.mateThreat[stm] != MOVE_NONE) - return 8 * QueenValueMidgame - Sign[stm] * value; - else - return Sign[stm] * value; + return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v); } @@ -479,22 +479,18 @@ Value evaluate(const Position &pos, EvalInfo &ei, int threadID) { /// we should add scores from the pawn and material hash tables? Value quick_evaluate(const Position &pos) { - Color stm; - Value mgValue, egValue; - ScaleFactor factor[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; - Phase phase; assert(pos.is_ok()); - stm = pos.side_to_move(); + static const + ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; - mgValue = pos.mg_value(); - egValue = pos.eg_value(); - phase = pos.game_phase(); + Value mgv = pos.mg_value(); + Value egv = pos.eg_value(); + Phase ph = pos.game_phase(); + Color stm = pos.side_to_move(); - Value value = scale_by_game_phase(mgValue, egValue, phase, factor); - - return Sign[stm] * value; + return Sign[stm] * scale_by_game_phase(mgv, egv, ph, sf); } @@ -528,9 +524,11 @@ void init_eval(int threads) { /// quit_eval() releases heap-allocated memory at program termination. void quit_eval() { - for(int i = 0; i < THREAD_MAX; i++) { - delete PawnTable[i]; - delete MaterialTable[i]; + + for (int i = 0; i < THREAD_MAX; i++) + { + delete PawnTable[i]; + delete MaterialTable[i]; } } @@ -538,32 +536,20 @@ void quit_eval() { /// read_weights() reads evaluation weights from the corresponding UCI /// parameters. -void read_weights(Color sideToMove) { - WeightMobilityMidgame = - compute_weight(get_option_value_int("Mobility (Middle Game)"), - WeightMobilityMidgameInternal); - WeightMobilityEndgame = - compute_weight(get_option_value_int("Mobility (Endgame)"), - WeightMobilityEndgameInternal); - WeightPawnStructureMidgame = - compute_weight(get_option_value_int("Pawn Structure (Middle Game)"), - WeightPawnStructureMidgameInternal); - WeightPawnStructureEndgame = - compute_weight(get_option_value_int("Pawn Structure (Endgame)"), - WeightPawnStructureEndgameInternal); - WeightPassedPawnsMidgame = - compute_weight(get_option_value_int("Passed Pawns (Middle Game)"), - WeightPassedPawnsMidgameInternal); - WeightPassedPawnsEndgame = - compute_weight(get_option_value_int("Passed Pawns (Endgame)"), - WeightPassedPawnsEndgameInternal); - WeightKingSafety[sideToMove] = - compute_weight(get_option_value_int("Cowardice"), WeightKingSafetyInternal); - WeightKingSafety[opposite_color(sideToMove)] = - compute_weight(get_option_value_int("Aggressiveness"), - WeightKingSafetyInternal); - WeightKingSafety[opposite_color(sideToMove)] = - (get_option_value_int("Aggressiveness") * 0x100) / 100; +void read_weights(Color us) { + + WeightMobilityMidgame = weight_option("Mobility (Middle Game)", WeightMobilityMidgameInternal); + WeightMobilityEndgame = weight_option("Mobility (Endgame)", WeightMobilityEndgameInternal); + WeightPawnStructureMidgame = weight_option("Pawn Structure (Middle Game)", WeightPawnStructureMidgameInternal); + WeightPawnStructureEndgame = weight_option("Pawn Structure (Endgame)", WeightPawnStructureEndgameInternal); + WeightPassedPawnsMidgame = weight_option("Passed Pawns (Middle Game)", WeightPassedPawnsMidgameInternal); + WeightPassedPawnsEndgame = weight_option("Passed Pawns (Endgame)", WeightPassedPawnsEndgameInternal); + + Color them = opposite_color(us); + + WeightKingSafety[us] = weight_option("Cowardice", WeightKingSafetyInternal); + WeightKingSafety[them] = weight_option("Aggressiveness", WeightKingOppSafetyInternal); + WeightSpace = weight_option("Space", WeightSpaceInternal); init_safety(); } @@ -580,17 +566,20 @@ namespace { Color them = opposite_color(us); // King attack - if (b & ei.attackZone[us]) + if (b & ei.kingZone[us]) { - ei.attackCount[us]++; - ei.attackWeight[us] += AttackWeight; - Bitboard bb = (b & ei.attackedBy[them][KING]); - if (bb) - ei.attacked[us] += count_1s_max_15(bb); + ei.kingAttackersCount[us]++; + ei.kingAttackersWeight[us] += AttackWeight; + Bitboard bb = (b & ei.attackedBy[them][KING]); + if (bb) + ei.kingAdjacentZoneAttacksCount[us] += count_1s_max_15(bb); } + // Remove squares protected by enemy pawns + Bitboard bb = (b & ~ei.attackedBy[them][PAWN]); + // Mobility - int mob = count_1s_max_15(b & ~p.pieces_of_color(us)); + int mob = count_1s_max_15(bb & ~p.pieces_of_color(us)); ei.mgMobility += Sign[us] * mgBonus[mob]; ei.egMobility += Sign[us] * egBonus[mob]; @@ -607,7 +596,7 @@ namespace { if (v && (p.pawn_attacks(them, s) & p.pawns(us))) { bonus += v / 2; - if ( p.knight_count(them) == 0 + if ( p.piece_count(them, KNIGHT) == 0 && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB) bonus += v; } @@ -622,7 +611,7 @@ namespace { void evaluate_knight(const Position &p, Square s, Color us, EvalInfo &ei) { - Bitboard b = p.knight_attacks(s); + Bitboard b = p.piece_attacks(s); ei.attackedBy[us][KNIGHT] |= b; // King attack, mobility and outposts @@ -650,7 +639,6 @@ namespace { void evaluate_rook(const Position &p, Square s, Color us, EvalInfo &ei) { - //Bitboard b = p.rook_attacks(s); Bitboard b = rook_attacks_bb(s, p.occupied_squares() & ~p.rooks_and_queens(us)); ei.attackedBy[us][ROOK] |= b; @@ -688,8 +676,9 @@ namespace { // king has lost right to castle if (mob > 6 || ei.pi->file_is_half_open(us, f)) return; - + Square ksq = p.king_square(us); + if ( square_file(ksq) >= FILE_E && square_file(s) > square_file(ksq) && (relative_rank(us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s))) @@ -716,7 +705,7 @@ namespace { void evaluate_queen(const Position &p, Square s, Color us, EvalInfo &ei) { - Bitboard b = p.queen_attacks(s); + Bitboard b = p.piece_attacks(s); ei.attackedBy[us][QUEEN] |= b; // King attack and mobility @@ -734,6 +723,10 @@ namespace { } } + inline Bitboard shiftRowsDown(const Bitboard& b, int num) { + + return b >> (num << 3); + } // evaluate_king() assigns bonuses and penalties to a king of a given // color on a given square. @@ -742,147 +735,156 @@ namespace { int shelter = 0, sign = Sign[us]; - // King shelter. - if(relative_rank(us, s) <= RANK_4) { - Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s); - Rank r = square_rank(s); - for(int i = 0; i < 3; i++) - shelter += count_1s_8bit(pawns >> ((r+(i+1)*sign) * 8)) * (64>>i); - ei.mgValue += sign * Value(shelter); + // King shelter + if (relative_rank(us, s) <= RANK_4) + { + Bitboard pawns = p.pawns(us) & this_and_neighboring_files_bb(s); + Rank r = square_rank(s); + for (int i = 1; i < 4; i++) + shelter += count_1s_8bit(shiftRowsDown(pawns, r+i*sign)) * (128>>i); + + ei.mgValue += sign * Value(shelter); } // King safety. This is quite complicated, and is almost certainly far // from optimally tuned. Color them = opposite_color(us); - if(p.queen_count(them) >= 1 && ei.attackCount[them] >= 2 - && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame - && ei.attacked[them]) { + if ( p.piece_count(them, QUEEN) >= 1 + && ei.kingAttackersCount[them] >= 2 + && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame + && ei.kingAdjacentZoneAttacksCount[them]) + { // Is it the attackers turn to move? bool sente = (them == p.side_to_move()); // Find the attacked squares around the king which has no defenders - // apart from the king itself: + // apart from the king itself Bitboard undefended = - ei.attacked_by(them) & ~ei.attacked_by(us, PAWN) - & ~ei.attacked_by(us, KNIGHT) & ~ei.attacked_by(us, BISHOP) - & ~ei.attacked_by(us, ROOK) & ~ei.attacked_by(us, QUEEN) - & ei.attacked_by(us, KING); + ei.attacked_by(them) & ~ei.attacked_by(us, PAWN) + & ~ei.attacked_by(us, KNIGHT) & ~ei.attacked_by(us, BISHOP) + & ~ei.attacked_by(us, ROOK) & ~ei.attacked_by(us, QUEEN) + & ei.attacked_by(us, KING); + Bitboard occ = p.occupied_squares(), b, b2; // Initialize the 'attackUnits' variable, which is used later on as an - // index to the SafetyTable[] array. The initial is based on the number - // and types of the attacking pieces, the number of attacked and + // index to the SafetyTable[] array. The initial value is based on the + // number and types of the attacking pieces, the number of attacked and // undefended squares around the king, the square of the king, and the // quality of the pawn shelter. int attackUnits = - Min((ei.attackCount[them] * ei.attackWeight[them]) / 2, 25) - + (ei.attacked[them] + count_1s_max_15(undefended)) * 3 - + InitKingDanger[relative_square(us, s)] - shelter / 32; + Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25) + + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15(undefended)) * 3 + + InitKingDanger[relative_square(us, s)] - (shelter >> 5); - // Analyse safe queen contact checks: + // Analyse safe queen contact checks b = undefended & ei.attacked_by(them, QUEEN) & ~p.pieces_of_color(them); - if(b) { + if (b) + { Bitboard attackedByOthers = - ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT) - | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK); + ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT) + | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK); + b &= attackedByOthers; - if(b) { + if (b) + { // The bitboard b now contains the squares available for safe queen // contact checks. int count = count_1s_max_15(b); - attackUnits += QueenContactCheckBonus * count * (sente? 2 : 1); + attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1); // Is there a mate threat? - if(QueenContactMates && !p.is_check()) { + if (QueenContactMates && !p.is_check()) + { Bitboard escapeSquares = - p.king_attacks(s) & ~p.pieces_of_color(us) & ~attackedByOthers; - while(b) { - Square from, to = pop_1st_bit(&b); - if(!(escapeSquares - & ~queen_attacks_bb(to, occ & clear_mask_bb(s)))) { - // We have a mate, unless the queen is pinned or there - // is an X-ray attack through the queen. - for(int i = 0; i < p.queen_count(them); i++) { - from = p.queen_list(them, i); - if(bit_is_set(p.queen_attacks(from), to) - && !bit_is_set(p.pinned_pieces(them), from) - && !(rook_attacks_bb(to, occ & clear_mask_bb(from)) - & p.rooks_and_queens(us)) - && !(rook_attacks_bb(to, occ & clear_mask_bb(from)) - & p.rooks_and_queens(us))) - ei.mateThreat[them] = make_move(from, to); + p.piece_attacks(s) & ~p.pieces_of_color(us) & ~attackedByOthers; + + while (b) + { + Square from, to = pop_1st_bit(&b); + if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[s]))) + { + // We have a mate, unless the queen is pinned or there + // is an X-ray attack through the queen. + for (int i = 0; i < p.piece_count(them, QUEEN); i++) + { + from = p.piece_list(them, QUEEN, i); + if ( bit_is_set(p.piece_attacks(from), to) + && !bit_is_set(p.pinned_pieces(them), from) + && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us)) + && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us))) + + ei.mateThreat[them] = make_move(from, to); + } } - } } } } } - // Analyse safe rook contact checks: - if(RookContactCheckBonus) { - b = undefended & ei.attacked_by(them, ROOK) & ~p.pieces_of_color(them); - if(b) { - Bitboard attackedByOthers = - ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT) - | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, QUEEN); - b &= attackedByOthers; - if(b) { - int count = count_1s_max_15(b); - attackUnits += (RookContactCheckBonus * count * (sente? 2 : 1)); - } - } - } - - // Analyse safe distance checks: - if(QueenCheckBonus > 0 || RookCheckBonus > 0) { - b = p.rook_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); + // Analyse safe distance checks + if (QueenCheckBonus > 0 || RookCheckBonus > 0) + { + b = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - // Queen checks - b2 = b & ei.attacked_by(them, QUEEN); - if(b2) attackUnits += QueenCheckBonus * count_1s_max_15(b2); + // Queen checks + b2 = b & ei.attacked_by(them, QUEEN); + if( b2) + attackUnits += QueenCheckBonus * count_1s_max_15(b2); - // Rook checks - b2 = b & ei.attacked_by(them, ROOK); - if(b2) attackUnits += RookCheckBonus * count_1s_max_15(b2); + // Rook checks + b2 = b & ei.attacked_by(them, ROOK); + if (b2) + attackUnits += RookCheckBonus * count_1s_max_15(b2); } - if(QueenCheckBonus > 0 || BishopCheckBonus > 0) { - b = p.bishop_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - // Queen checks - b2 = b & ei.attacked_by(them, QUEEN); - if(b2) attackUnits += QueenCheckBonus * count_1s_max_15(b2); - - // Bishop checks - b2 = b & ei.attacked_by(them, BISHOP); - if(b2) attackUnits += BishopCheckBonus * count_1s_max_15(b2); + if (QueenCheckBonus > 0 || BishopCheckBonus > 0) + { + b = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); + + // Queen checks + b2 = b & ei.attacked_by(them, QUEEN); + if (b2) + attackUnits += QueenCheckBonus * count_1s_max_15(b2); + + // Bishop checks + b2 = b & ei.attacked_by(them, BISHOP); + if (b2) + attackUnits += BishopCheckBonus * count_1s_max_15(b2); } - if(KnightCheckBonus > 0) { - b = p.knight_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - // Knight checks - b2 = b & ei.attacked_by(them, KNIGHT); - if(b2) attackUnits += KnightCheckBonus * count_1s_max_15(b2); + if (KnightCheckBonus > 0) + { + b = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); + + // Knight checks + b2 = b & ei.attacked_by(them, KNIGHT); + if (b2) + attackUnits += KnightCheckBonus * count_1s_max_15(b2); } // Analyse discovered checks (only for non-pawns right now, consider // adding pawns later). - if(DiscoveredCheckBonus) { + if (DiscoveredCheckBonus) + { b = p.discovered_check_candidates(them) & ~p.pawns(); - if(b) - attackUnits += - DiscoveredCheckBonus * count_1s_max_15(b) * (sente? 2 : 1); + if (b) + attackUnits += DiscoveredCheckBonus * count_1s_max_15(b) * (sente? 2 : 1); } // Has a mate threat been found? We don't do anything here if the // side with the mating move is the side to move, because in that // case the mating side will get a huge bonus at the end of the main // evaluation function instead. - if(ei.mateThreat[them] != MOVE_NONE) - attackUnits += MateThreatBonus; + if (ei.mateThreat[them] != MOVE_NONE) + attackUnits += MateThreatBonus; // Ensure that attackUnits is between 0 and 99, in order to avoid array // out of bounds errors: - if(attackUnits < 0) attackUnits = 0; - if(attackUnits >= 100) attackUnits = 99; + if (attackUnits < 0) + attackUnits = 0; + + if (attackUnits >= 100) + attackUnits = 99; // Finally, extract the king safety score from the SafetyTable[] array. // Add the score to the evaluation, and also to ei.futilityMargin. The @@ -891,9 +893,11 @@ namespace { // capturing a single attacking piece can therefore result in a score // change far bigger than the value of the captured piece. Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[us]); + ei.mgValue -= sign * v; - if(us == p.side_to_move()) - ei.futilityMargin += v; + + if (us == p.side_to_move()) + ei.futilityMargin += v; } } @@ -901,141 +905,161 @@ namespace { // evaluate_passed_pawns() evaluates the passed pawns for both sides. void evaluate_passed_pawns(const Position &pos, EvalInfo &ei) { + bool hasUnstoppable[2] = {false, false}; int movesToGo[2] = {100, 100}; - for(Color us = WHITE; us <= BLACK; us++) { - Color them = opposite_color(us); - Square ourKingSq = pos.king_square(us); - Square theirKingSq = pos.king_square(them); - Bitboard b = ei.pi->passed_pawns() & pos.pawns(us), b2, b3, b4; + for (Color us = WHITE; us <= BLACK; us++) + { + Color them = opposite_color(us); + Square ourKingSq = pos.king_square(us); + Square theirKingSq = pos.king_square(them); + Bitboard b = ei.pi->passed_pawns() & pos.pawns(us), b2, b3, b4; - while(b) { - Square s = pop_1st_bit(&b); - assert(pos.piece_on(s) == pawn_of_color(us)); - assert(pos.pawn_is_passed(us, s)); - - int r = int(relative_rank(us, s) - RANK_2); - int tr = Max(0, r * (r-1)); - Square blockSq = s + pawn_push(us); - - // Base bonus based on rank: - Value mbonus = Value(20 * tr); - Value ebonus = Value(10 + r * r * 10); - - // Adjust bonus based on king proximity: - ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr); - ebonus -= - Value(square_distance(ourKingSq, blockSq + pawn_push(us)) * 1 * tr); - ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr); - - // If the pawn is free to advance, increase bonus: - if(pos.square_is_empty(blockSq)) { - - b2 = squares_in_front_of(us, s); - b3 = b2 & ei.attacked_by(them); - b4 = b2 & ei.attacked_by(us); - if((b2 & pos.pieces_of_color(them)) == EmptyBoardBB) { - // There are no enemy pieces in the pawn's path! Are any of the - // squares in the pawn's path attacked by the enemy? - if(b3 == EmptyBoardBB) - // No enemy attacks, huge bonus! - ebonus += Value(tr * ((b2 == b4)? 17 : 15)); - else - // OK, there are enemy attacks. Are those squares which are - // attacked by the enemy also attacked by us? If yes, big bonus - // (but smaller than when there are no enemy attacks), if no, - // somewhat smaller bonus. - ebonus += Value(tr * (((b3 & b4) == b3)? 13 : 8)); - } - else { - // There are some enemy pieces in the pawn's path. While this is - // sad, we still assign a moderate bonus if all squares in the path - // which are either occupied by or attacked by enemy pieces are - // also attacked by us. - if(((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB) - ebonus += Value(tr * 6); - } - // At last, add a small bonus when there are no *friendly* pieces - // in the pawn's path: - if((b2 & pos.pieces_of_color(us)) == EmptyBoardBB) - ebonus += Value(tr); - } + while (b) + { + Square s = pop_1st_bit(&b); + + assert(pos.piece_on(s) == pawn_of_color(us)); + assert(pos.pawn_is_passed(us, s)); + + int r = int(relative_rank(us, s) - RANK_2); + int tr = Max(0, r * (r - 1)); + Square blockSq = s + pawn_push(us); + + // Base bonus based on rank + Value mbonus = Value(20 * tr); + Value ebonus = Value(10 + r * r * 10); + + // Adjust bonus based on king proximity + if (tr != 0) + { + ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr); + ebonus -= Value(square_distance(ourKingSq, blockSq + pawn_push(us)) * 1 * tr); + ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr); + + // If the pawn is free to advance, increase bonus + if (pos.square_is_empty(blockSq)) + { + b2 = squares_in_front_of(us, s); + b3 = b2 & ei.attacked_by(them); + b4 = b2 & ei.attacked_by(us); + + // If there is an enemy rook or queen attacking the pawn from behind, + // add all X-ray attacks by the rook or queen. + if ( bit_is_set(ei.attacked_by(them,ROOK) | ei.attacked_by(them,QUEEN),s) + && (squares_behind(us, s) & pos.rooks_and_queens(them))) + b3 = b2; + + if ((b2 & pos.pieces_of_color(them)) == EmptyBoardBB) + { + // There are no enemy pieces in the pawn's path! Are any of the + // squares in the pawn's path attacked by the enemy? + if (b3 == EmptyBoardBB) + // No enemy attacks, huge bonus! + ebonus += Value(tr * (b2 == b4 ? 17 : 15)); + else + // OK, there are enemy attacks. Are those squares which are + // attacked by the enemy also attacked by us? If yes, big bonus + // (but smaller than when there are no enemy attacks), if no, + // somewhat smaller bonus. + ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8)); + } + else + { + // There are some enemy pieces in the pawn's path. While this is + // sad, we still assign a moderate bonus if all squares in the path + // which are either occupied by or attacked by enemy pieces are + // also attacked by us. + if (((b3 | (b2 & pos.pieces_of_color(them))) & ~b4) == EmptyBoardBB) + ebonus += Value(tr * 6); + } + // At last, add a small bonus when there are no *friendly* pieces + // in the pawn's path. + if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB) + ebonus += Value(tr); + } + } - // If the pawn is supported by a friendly pawn, increase bonus. - b2 = pos.pawns(us) & neighboring_files_bb(s); - if(b2 & rank_bb(s)) - ebonus += Value(r * 20); - else if(pos.pawn_attacks(them, s) & b2) - ebonus += Value(r * 12); - - // If the other side has only a king, check whether the pawn is - // unstoppable: - if(pos.non_pawn_material(them) == Value(0)) { - Square qsq; - int d; - - qsq = relative_square(us, make_square(square_file(s), RANK_8)); - d = square_distance(s, qsq) - square_distance(theirKingSq, qsq) - + ((us == pos.side_to_move())? 0 : 1); - - if(d < 0) { - int mtg = RANK_8 - relative_rank(us, s); - int blockerCount = - count_1s_max_15(squares_in_front_of(us,s)&pos.occupied_squares()); - mtg += blockerCount; - d += blockerCount; - if(d < 0) { - hasUnstoppable[us] = true; - movesToGo[us] = Min(movesToGo[us], mtg); + // If the pawn is supported by a friendly pawn, increase bonus + b2 = pos.pawns(us) & neighboring_files_bb(s); + if (b2 & rank_bb(s)) + ebonus += Value(r * 20); + else if (pos.pawn_attacks(them, s) & b2) + ebonus += Value(r * 12); + + // If the other side has only a king, check whether the pawn is + // unstoppable + if (pos.non_pawn_material(them) == Value(0)) + { + Square qsq; + int d; + + qsq = relative_square(us, make_square(square_file(s), RANK_8)); + d = square_distance(s, qsq) + - square_distance(theirKingSq, qsq) + + (us != pos.side_to_move()); + + if (d < 0) + { + int mtg = RANK_8 - relative_rank(us, s); + int blockerCount = count_1s_max_15(squares_in_front_of(us,s) & pos.occupied_squares()); + mtg += blockerCount; + d += blockerCount; + if (d < 0) + { + hasUnstoppable[us] = true; + movesToGo[us] = Min(movesToGo[us], mtg); + } + } + } + // Rook pawns are a special case: They are sometimes worse, and + // sometimes better than other passed pawns. It is difficult to find + // good rules for determining whether they are good or bad. For now, + // we try the following: Increase the value for rook pawns if the + // other side has no pieces apart from a knight, and decrease the + // value if the other side has a rook or queen. + if (square_file(s) == FILE_A || square_file(s) == FILE_H) + { + if( pos.non_pawn_material(them) <= KnightValueMidgame + && pos.piece_count(them, KNIGHT) <= 1) + ebonus += ebonus / 4; + else if(pos.rooks_and_queens(them)) + ebonus -= ebonus / 4; } - } - } - // Rook pawns are a special case: They are sometimes worse, and - // sometimes better than other passed pawns. It is difficult to find - // good rules for determining whether they are good or bad. For now, - // we try the following: Increase the value for rook pawns if the - // other side has no pieces apart from a knight, and decrease the - // value if the other side has a rook or queen. - if(square_file(s) == FILE_A || square_file(s) == FILE_H) { - if(pos.non_pawn_material(them) == KnightValueMidgame - && pos.knight_count(them) == 1) - ebonus += ebonus / 4; - else if(pos.rooks_and_queens(them)) - ebonus -= ebonus / 4; - } - // Add the scores for this pawn to the middle game and endgame eval. - ei.mgValue += apply_weight(Sign[us] * mbonus, WeightPassedPawnsMidgame); - ei.egValue += apply_weight(Sign[us] * ebonus, WeightPassedPawnsEndgame); - } + // Add the scores for this pawn to the middle game and endgame eval. + ei.mgValue += apply_weight(Sign[us] * mbonus, WeightPassedPawnsMidgame); + ei.egValue += apply_weight(Sign[us] * ebonus, WeightPassedPawnsEndgame); + } } // Does either side have an unstoppable passed pawn? - if(hasUnstoppable[WHITE] && !hasUnstoppable[BLACK]) - ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]); - else if(hasUnstoppable[BLACK] && !hasUnstoppable[WHITE]) - ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]); - else if(hasUnstoppable[BLACK] && hasUnstoppable[WHITE]) { - // Both sides have unstoppable pawns! Try to find out who queens - // first. We begin by transforming 'movesToGo' to the number of - // plies until the pawn queens for both sides: - movesToGo[WHITE] *= 2; - movesToGo[BLACK] *= 2; - movesToGo[pos.side_to_move()]--; - - // If one side queens at least three plies before the other, that - // side wins: - if(movesToGo[WHITE] <= movesToGo[BLACK] - 3) - ei.egValue += UnstoppablePawnValue - Value(0x40 * (movesToGo[WHITE]/2)); - else if(movesToGo[BLACK] <= movesToGo[WHITE] - 3) - ei.egValue -= UnstoppablePawnValue - Value(0x40 * (movesToGo[BLACK]/2)); - - // We could also add some rules about the situation when one side - // queens exactly one ply before the other: Does the first queen - // check the opponent's king, or attack the opponent's queening square? - // This is slightly tricky to get right, because it is possible that - // the opponent's king has moved somewhere before the first pawn queens. + if (hasUnstoppable[WHITE] && !hasUnstoppable[BLACK]) + ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]); + else if (hasUnstoppable[BLACK] && !hasUnstoppable[WHITE]) + ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]); + else if (hasUnstoppable[BLACK] && hasUnstoppable[WHITE]) + { + // Both sides have unstoppable pawns! Try to find out who queens + // first. We begin by transforming 'movesToGo' to the number of + // plies until the pawn queens for both sides. + movesToGo[WHITE] *= 2; + movesToGo[BLACK] *= 2; + movesToGo[pos.side_to_move()]--; + + // If one side queens at least three plies before the other, that + // side wins. + if (movesToGo[WHITE] <= movesToGo[BLACK] - 3) + ei.egValue += UnstoppablePawnValue - Value(0x40 * (movesToGo[WHITE]/2)); + else if(movesToGo[BLACK] <= movesToGo[WHITE] - 3) + ei.egValue -= UnstoppablePawnValue - Value(0x40 * (movesToGo[BLACK]/2)); + + // We could also add some rules about the situation when one side + // queens exactly one ply before the other: Does the first queen + // check the opponent's king, or attack the opponent's queening square? + // This is slightly tricky to get right, because it is possible that + // the opponent's king has moved somewhere before the first pawn queens. } } @@ -1046,26 +1070,19 @@ namespace { void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us, EvalInfo &ei) { - Piece pawn = pawn_of_color(opposite_color(us)); - Square b6, b8; - assert(square_is_ok(s)); assert(pos.piece_on(s) == bishop_of_color(us)); - if(square_file(s) == FILE_A) { - b6 = relative_square(us, SQ_B6); - b8 = relative_square(us, SQ_B8); - } - else { - b6 = relative_square(us, SQ_G6); - b8 = relative_square(us, SQ_G8); - } + Square b6 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B6 : SQ_G6); + Square b8 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B8 : SQ_G8); - if(pos.piece_on(b6) == pawn && pos.see(s, b6) < 0 && pos.see(s, b8) < 0) { - ei.mgValue -= Sign[us] * TrappedBishopA7H7Penalty; - ei.egValue -= Sign[us] * TrappedBishopA7H7Penalty; + if ( pos.piece_on(b6) == pawn_of_color(opposite_color(us)) + && pos.see(s, b6) < 0 + && pos.see(s, b8) < 0) + { + ei.mgValue -= Sign[us] * TrappedBishopA7H7Penalty; + ei.egValue -= Sign[us] * TrappedBishopA7H7Penalty; } - } @@ -1083,61 +1100,97 @@ namespace { assert(square_is_ok(s)); assert(pos.piece_on(s) == bishop_of_color(us)); - if(square_file(s) == FILE_A) { - b2 = relative_square(us, SQ_B2); - b3 = relative_square(us, SQ_B3); - c3 = relative_square(us, SQ_C3); + if (square_file(s) == FILE_A) + { + b2 = relative_square(us, SQ_B2); + b3 = relative_square(us, SQ_B3); + c3 = relative_square(us, SQ_C3); } - else { - b2 = relative_square(us, SQ_G2); - b3 = relative_square(us, SQ_G3); - c3 = relative_square(us, SQ_F3); + else + { + b2 = relative_square(us, SQ_G2); + b3 = relative_square(us, SQ_G3); + c3 = relative_square(us, SQ_F3); } - if(pos.piece_on(b2) == pawn) { - Value penalty; + if (pos.piece_on(b2) == pawn) + { + Value penalty; - if(!pos.square_is_empty(b3)) - penalty = 2*TrappedBishopA1H1Penalty; - else if(pos.piece_on(c3) == pawn) - penalty = TrappedBishopA1H1Penalty; - else - penalty = TrappedBishopA1H1Penalty / 2; + if (!pos.square_is_empty(b3)) + penalty = 2*TrappedBishopA1H1Penalty; + else if (pos.piece_on(c3) == pawn) + penalty = TrappedBishopA1H1Penalty; + else + penalty = TrappedBishopA1H1Penalty / 2; + + ei.mgValue -= Sign[us] * penalty; + ei.egValue -= Sign[us] * penalty; + } + } - ei.mgValue -= Sign[us] * penalty; - ei.egValue -= Sign[us] * penalty; + + // evaluate_space() computes the space evaluation for a given side. The + // space evaluation is a simple bonus based on the number of safe squares + // available for minor pieces on the central four files on ranks 2--4. Safe + // squares one, two or three squares behind a friendly pawn are counted + // twice. Finally, the space bonus is scaled by a weight taken from the + // material hash table. + + void evaluate_space(const Position &pos, Color us, EvalInfo &ei) { + + Color them = opposite_color(us); + + // Find the safe squares for our pieces inside the area defined by + // SpaceMask[us]. A square is unsafe it is attacked by an enemy + // pawn, or if it is undefended and attacked by an enemy piece. + + Bitboard safeSquares = SpaceMask[us] + & ~pos.pawns(us) + & ~ei.attacked_by(them, PAWN) + & ~(~ei.attacked_by(us) & ei.attacked_by(them)); + + // Find all squares which are at most three squares behind some friendly + // pawn. + Bitboard behindFriendlyPawns = pos.pawns(us); + if (us == WHITE) + { + behindFriendlyPawns |= (behindFriendlyPawns >> 8); + behindFriendlyPawns |= (behindFriendlyPawns >> 16); + } + else + { + behindFriendlyPawns |= (behindFriendlyPawns << 8); + behindFriendlyPawns |= (behindFriendlyPawns << 16); } + int space = count_1s_max_15(safeSquares) + + count_1s_max_15(behindFriendlyPawns & safeSquares); + + ei.mgValue += Sign[us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace); } - // apply_weight applies an evaluation weight to a value. + // apply_weight() applies an evaluation weight to a value inline Value apply_weight(Value v, int w) { return (v*w) / 0x100; } - // scale_by_game_phase interpolates between a middle game and an endgame + // scale_by_game_phase() interpolates between a middle game and an endgame // score, based on game phase. It also scales the return value by a // ScaleFactor array. - Value scale_by_game_phase(Value mv, Value ev, Phase ph, ScaleFactor sf[]) { + Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) { + assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE); assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE); assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); - if(ev > Value(0)) - ev = apply_scale_factor(ev, sf[WHITE]); - else - ev = apply_scale_factor(ev, sf[BLACK]); - - // Superlinear interpolator - int sli_ph = int(ph); - sli_ph -= (64 - sli_ph) / 4; - sli_ph = Min(PHASE_MIDGAME, Max(PHASE_ENDGAME, sli_ph)); // ceiling + ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]); - Value result = Value(int((mv * sli_ph + ev * (128 - sli_ph)) / 128)); + Value result = Value(int((mv * ph + ev * (128 - ph)) / 128)); return Value(int(result) & ~(GrainSize - 1)); } @@ -1155,48 +1208,57 @@ namespace { // an UCI-configurable weight with an internal weight. int compute_weight(int uciWeight, int internalWeight) { + uciWeight = (uciWeight * 0x100) / 100; return (uciWeight * internalWeight) / 0x100; } + // helper used in read_weights() + int weight_option(const std::string& opt, int weight) { + + return compute_weight(get_option_value_int(opt), weight); + } + + // init_safety() initizes the king safety evaluation, based on UCI // parameters. It is called from read_weights(). void init_safety() { - double a, b; - int maxSlope, peak, i, j; QueenContactCheckBonus = get_option_value_int("Queen Contact Check Bonus"); - RookContactCheckBonus = get_option_value_int("Rook Contact Check Bonus"); - QueenCheckBonus = get_option_value_int("Queen Check Bonus"); - RookCheckBonus = get_option_value_int("Rook Check Bonus"); - BishopCheckBonus = get_option_value_int("Bishop Check Bonus"); - KnightCheckBonus = get_option_value_int("Knight Check Bonus"); - DiscoveredCheckBonus = get_option_value_int("Discovered Check Bonus"); - MateThreatBonus = get_option_value_int("Mate Threat Bonus"); - - a = get_option_value_int("King Safety Coefficient") / 100.0; - b = get_option_value_int("King Safety X Intercept") * 1.0; - maxSlope = get_option_value_int("King Safety Max Slope"); - peak = (get_option_value_int("King Safety Max Value") * 256) / 100; - - for(i = 0; i < 100; i++) { - if(i < b) SafetyTable[i] = Value(0); - else if(get_option_value_string("King Safety Curve") == "Quadratic") - SafetyTable[i] = Value((int)(a * (i - b) * (i - b))); - else if(get_option_value_string("King Safety Curve") == "Linear") - SafetyTable[i] = Value((int)(100 * a * (i - b))); + QueenCheckBonus = get_option_value_int("Queen Check Bonus"); + RookCheckBonus = get_option_value_int("Rook Check Bonus"); + BishopCheckBonus = get_option_value_int("Bishop Check Bonus"); + KnightCheckBonus = get_option_value_int("Knight Check Bonus"); + DiscoveredCheckBonus = get_option_value_int("Discovered Check Bonus"); + MateThreatBonus = get_option_value_int("Mate Threat Bonus"); + + int maxSlope = get_option_value_int("King Safety Max Slope"); + int peak = get_option_value_int("King Safety Max Value") * 256 / 100; + double a = get_option_value_int("King Safety Coefficient") / 100.0; + double b = get_option_value_int("King Safety X Intercept"); + bool quad = (get_option_value_string("King Safety Curve") == "Quadratic"); + bool linear = (get_option_value_string("King Safety Curve") == "Linear"); + + for (int i = 0; i < 100; i++) + { + if (i < b) + SafetyTable[i] = Value(0); + else if(quad) + SafetyTable[i] = Value((int)(a * (i - b) * (i - b))); + else if(linear) + SafetyTable[i] = Value((int)(100 * a * (i - b))); } - for(i = 0; i < 100; i++) - if(SafetyTable[i+1] - SafetyTable[i] > maxSlope) { - for(j = i + 1; j < 100; j++) - SafetyTable[j] = SafetyTable[j-1] + Value(maxSlope); - } - for(i = 0; i < 100; i++) - if(SafetyTable[i] > Value(peak)) - SafetyTable[i] = Value(peak); - } + for (int i = 0; i < 100; i++) + { + if (SafetyTable[i+1] - SafetyTable[i] > maxSlope) + for (int j = i + 1; j < 100; j++) + SafetyTable[j] = SafetyTable[j-1] + Value(maxSlope); + if (SafetyTable[i] > Value(peak)) + SafetyTable[i] = Value(peak); + } + } }