X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=47d5eb3e9bc93760432f369c04195afff4f20ac3;hp=65fd691ada7e3b55f8c203f3c8b76fa5fe391109;hb=94b9c65e09b5d396bebb29b62d9979139b5fbdfa;hpb=b14846b6d74373762280420ffc97759113cf0c0c diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 65fd691a..47d5eb3e 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -29,7 +29,6 @@ #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "scale.h" #include "thread.h" #include "ucioption.h" @@ -130,28 +129,22 @@ namespace { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8 }; - // ThreatBonus[][] contains bonus according to which piece type - // attacks which one. - #define Z S(0, 0) - + // ThreatBonus[attacking][attacked] contains bonus according to which + // piece type attacks which one. const Score ThreatBonus[8][8] = { - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, S(18,37), Z, S(37,47), S(55,97), S(55,97), Z, Z }, // KNIGHT attacks - { Z, S(18,37), S(37,47), Z, S(55,97), S(55,97), Z, Z }, // BISHOP attacks - { Z, S( 9,27), S(27,47), S(27,47), Z, S(37,47), Z, Z }, // ROOK attacks - { Z, S(27,37), S(27,37), S(27,37), S(27,37), Z, Z, Z }, // QUEEN attacks - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, Z, Z, Z, Z, Z, Z, Z } // not used + {}, {}, + { S(0, 0), S( 7, 39), S( 0, 0), S(24, 49), S(41,100), S(41,100) }, // KNIGHT + { S(0, 0), S( 7, 39), S(24, 49), S( 0, 0), S(41,100), S(41,100) }, // BISHOP + { S(0, 0), S(-1, 29), S(15, 49), S(15, 49), S( 0, 0), S(24, 49) }, // ROOK + { S(0, 0), S(15, 39), S(15, 39), S(15, 39), S(15, 39), S( 0, 0) } // QUEEN }; // ThreatedByPawnPenalty[] contains a penalty according to which piece // type is attacked by an enemy pawn. const Score ThreatedByPawnPenalty[8] = { - Z, Z, S(56, 70), S(56, 70), S(76, 99), S(86, 118), Z, Z + S(0, 0), S(0, 0), S(56, 70), S(56, 70), S(76, 99), S(86, 118) }; - #undef Z #undef S // Bonus for unstoppable passed pawns @@ -208,28 +201,16 @@ namespace { /// the strength of the enemy attack are added up into an integer, which /// is used as an index to KingDangerTable[]. - // Attack weights for each piece type and table indexed on piece type - const int QueenAttackWeight = 5; - const int RookAttackWeight = 3; - const int BishopAttackWeight = 2; - const int KnightAttackWeight = 2; - - const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight }; + // KingAttackWeights[] contains king attack weights by piece type + const int KingAttackWeights[8] = { 0, 0, 2, 2, 3, 5 }; // Bonuses for enemy's safe checks const int QueenContactCheckBonus = 3; - const int DiscoveredCheckBonus = 3; const int QueenCheckBonus = 2; const int RookCheckBonus = 1; const int BishopCheckBonus = 1; const int KnightCheckBonus = 1; - // Scan for queen contact mates? - const bool QueenContactMates = true; - - // Bonus for having a mate threat - const int MateThreatBonus = 3; - // InitKingDanger[] contains bonuses based on the position of the defending // king. const int InitKingDanger[64] = { @@ -257,7 +238,10 @@ namespace { // Function prototypes template - Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID); + Value do_evaluate(const Position& pos, EvalInfo& ei); + + template + void init_attack_tables(const Position& pos, EvalInfo& ei); template void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei); @@ -269,7 +253,7 @@ namespace { void evaluate_threats(const Position& pos, EvalInfo& ei); template - void evaluate_space(const Position& pos, EvalInfo& ei); + int evaluate_space(const Position& pos, EvalInfo& ei); template void evaluate_passed_pawns(const Position& pos, EvalInfo& ei); @@ -291,22 +275,21 @@ namespace { /// evaluate() is the main evaluation function. It always computes two /// values, an endgame score and a middle game score, and interpolates /// between them based on the remaining material. -Value evaluate(const Position& pos, EvalInfo& ei, int threadID) { +Value evaluate(const Position& pos, EvalInfo& ei) { - return CpuHasPOPCNT ? do_evaluate(pos, ei, threadID) - : do_evaluate(pos, ei, threadID); + return CpuHasPOPCNT ? do_evaluate(pos, ei) + : do_evaluate(pos, ei); } namespace { template -Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { +Value do_evaluate(const Position& pos, EvalInfo& ei) { - Bitboard b; ScaleFactor factor[2]; assert(pos.is_ok()); - assert(threadID >= 0 && threadID < MAX_THREADS); + assert(pos.thread() >= 0 && pos.thread() < MAX_THREADS); assert(!pos.is_check()); memset(&ei, 0, sizeof(EvalInfo)); @@ -316,7 +299,7 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { ei.value = pos.value(); // Probe the material hash table - ei.mi = MaterialTable[threadID]->get_material_info(pos); + ei.mi = MaterialTable[pos.thread()]->get_material_info(pos); ei.value += ei.mi->material_value(); // If we have a specialized evaluation function for the current material @@ -329,25 +312,12 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { factor[BLACK] = ei.mi->scale_factor(pos, BLACK); // Probe the pawn hash table - ei.pi = PawnTable[threadID]->get_pawn_info(pos); + ei.pi = PawnTable[pos.thread()]->get_pawn_info(pos); ei.value += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); - // Initialize king attack bitboards and king attack zones for both sides - ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.king_square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.attacks_from(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] = ei.pi->pawn_attacks(WHITE); - b = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING]; - if (b) - ei.kingAttackersCount[WHITE] = count_1s_max_15(b)/2; - - ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK); - b = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING]; - if (b) - ei.kingAttackersCount[BLACK] = count_1s_max_15(b)/2; + // Initialize attack bitboards with pawns evaluation + init_attack_tables(pos, ei); + init_attack_tables(pos, ei); // Evaluate pieces evaluate_pieces_of_color(pos, ei); @@ -376,23 +346,23 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // 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) + // 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.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0); + ei.value += make_score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0); - else if ( square_file(pos.king_square(WHITE)) <= FILE_D - && square_file(pos.king_square(BLACK)) >= FILE_E) + else if ( square_file(pos.king_square(WHITE)) <= FILE_D + && square_file(pos.king_square(BLACK)) >= FILE_E) - ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0); + ei.value += make_score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0); - // Evaluate space for both sides - if (ei.mi->space_weight() > 0) - { - evaluate_space(pos, ei); - evaluate_space(pos, ei); - } + // Evaluate space for both sides + if (ei.mi->space_weight() > 0) + { + int s = evaluate_space(pos, ei) - evaluate_space(pos, ei); + ei.value += apply_weight(make_score(s * ei.mi->space_weight(), 0), Weights[Space]); + } } // Mobility @@ -402,8 +372,8 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // colored bishop endgames, and use a lower scale for those if ( phase < PHASE_MIDGAME && pos.opposite_colored_bishops() - && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && eg_value(ei.value) > Value(0)) - || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(ei.value) < Value(0)))) + && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && eg_value(ei.value) > VALUE_ZERO) + || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(ei.value) < VALUE_ZERO))) { ScaleFactor sf; @@ -428,11 +398,7 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { } // Interpolate between the middle game and the endgame score - Color stm = pos.side_to_move(); - - Value v = Sign[stm] * scale_by_game_phase(ei.value, phase, factor); - - return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v); + return Sign[pos.side_to_move()] * scale_by_game_phase(ei.value, phase, factor); } } // namespace @@ -502,6 +468,23 @@ void read_weights(Color us) { namespace { + // init_attack_tables() initializes king bitboards for both sides adding + // pawn attacks. To be done before other evaluations. + + template + void init_attack_tables(const Position& pos, EvalInfo& ei) { + + const Color Them = (Us == WHITE ? BLACK : WHITE); + + Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.king_square(Them)); + ei.kingZone[Us] = (b | (Us == WHITE ? b >> 8 : b << 8)); + ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); + b &= ei.attackedBy[Us][PAWN]; + if (b) + ei.kingAttackersCount[Us] = count_1s_max_15(b) / 2; + } + + // evaluate_outposts() evaluates bishop and knight outposts squares template @@ -559,7 +542,7 @@ namespace { if (b & ei.kingZone[Us]) { ei.kingAttackersCount[Us]++; - ei.kingAttackersWeight[Us] += AttackWeight[Piece]; + ei.kingAttackersWeight[Us] += KingAttackWeights[Piece]; Bitboard bb = (b & ei.attackedBy[Them][KING]); if (bb) ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15(bb); @@ -577,7 +560,7 @@ namespace { ei.value -= Sign[Us] * ThreatedByPawnPenalty[Piece]; // Bishop and knight outposts squares - if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Them)) + if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Us)) evaluate_outposts(pos, ei, s); // Special patterns: trapped bishops on a7/h7/a2/h2 @@ -705,10 +688,9 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); - Bitboard undefended, attackedByOthers, escapeSquares, occ, b, b1, b2, safe; - Square from, to; + Bitboard undefended, b, b1, b2, safe; bool sente; - int attackUnits, count, shelter = 0; + int attackUnits, shelter = 0; const Square ksq = pos.king_square(Us); // King shelter @@ -721,130 +703,78 @@ namespace { // King safety. This is quite complicated, and is almost certainly far // from optimally tuned. if ( pos.piece_count(Them, QUEEN) >= 1 - && ei.kingAttackersCount[Them] >= 2 - && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame + && ei.kingAttackersCount[Them] >= 2 + && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame && ei.kingAdjacentZoneAttacksCount[Them]) { - // Is it the attackers turn to move? - sente = (Them == pos.side_to_move()); - - // Find the attacked squares around the king which has no defenders - // apart from the king itself - undefended = ei.attacked_by(Them) & ei.attacked_by(Us, KING); - undefended &= ~( 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)); - - // Initialize the 'attackUnits' variable, which is used later on as an - // index to the KingDangerTable[] array. The initial value is based on - // the number and types of the enemy's attacking pieces, the number of - // attacked and undefended squares around our king, the square of the - // king, and the quality of the pawn shelter. - attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) - + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15(undefended)) - + InitKingDanger[relative_square(Us, ksq)] - - (shelter >> 5); - - // Analyse safe queen contact checks - b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them); - if (b) - { - attackedByOthers = ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT) - | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK); + // Is it the attackers turn to move? + sente = (Them == pos.side_to_move()); + + // Find the attacked squares around the king which has no defenders + // apart from the king itself + undefended = ei.attacked_by(Them) & ei.attacked_by(Us, KING); + undefended &= ~( 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)); + + // Initialize the 'attackUnits' variable, which is used later on as an + // index to the KingDangerTable[] array. The initial value is based on + // the number and types of the enemy's attacking pieces, the number of + // attacked and undefended squares around our king, the square of the + // king, and the quality of the pawn shelter. + attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) + + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15(undefended)) + + InitKingDanger[relative_square(Us, ksq)] + - shelter / 32; + + // Analyse enemy's safe queen contact checks. First find undefended + // squares around the king attacked by enemy queen... + b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them); + if (b) + { + // ...then remove squares not supported by another enemy piece + b &= ( ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT) + | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK)); + if (b) + attackUnits += QueenContactCheckBonus * count_1s_max_15(b) * (sente ? 2 : 1); + } + + // Analyse enemy's safe distance checks for sliders and knights + safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us)); - b &= attackedByOthers; + b1 = pos.attacks_from(ksq) & safe; + b2 = pos.attacks_from(ksq) & safe; - // Squares attacked by the queen and supported by another enemy piece and - // not defended by other pieces but our king. + // Enemy queen safe checks + b = (b1 | b2) & ei.attacked_by(Them, QUEEN); if (b) - { - // The bitboard b now contains the squares available for safe queen - // contact checks. - count = count_1s_max_15(b); - attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1); + attackUnits += QueenCheckBonus * count_1s_max_15(b); - // Is there a mate threat? - if (QueenContactMates && !pos.is_check()) - { - escapeSquares = pos.attacks_from(ksq) & ~pos.pieces_of_color(Us) & ~attackedByOthers; - occ = pos.occupied_squares(); - while (b) - { - to = pop_1st_bit(&b); - - // Do we have escape squares from queen contact check attack ? - if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[ksq]))) - { - // We have a mate, unless the queen is pinned or there - // is an X-ray attack through the queen. - for (int i = 0; i < pos.piece_count(Them, QUEEN); i++) - { - from = pos.piece_list(Them, QUEEN, i); - if ( bit_is_set(pos.attacks_from(from), to) - && !bit_is_set(pos.pinned_pieces(Them), from) - && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(ROOK, QUEEN, Us)) - && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(BISHOP, QUEEN, Us))) - - // Set the mate threat move - ei.mateThreat[Them] = make_move(from, to); - } - } - } - } - } - } + // Enemy rooks safe checks + b = b1 & ei.attacked_by(Them, ROOK); + if (b) + attackUnits += RookCheckBonus * count_1s_max_15(b); - // Analyse enemy's safe distance checks - safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us)); - - b1 = pos.attacks_from(ksq) & safe; - b2 = pos.attacks_from(ksq) & safe; - - // Enemy rooks safe checks - b = b1 & ei.attacked_by(Them, ROOK); - if (b) - attackUnits += RookCheckBonus * count_1s_max_15(b); - - // Enemy bishops safe checks - b = b2 & ei.attacked_by(Them, BISHOP); - if (b) - attackUnits += BishopCheckBonus * count_1s_max_15(b); - - // Enemy queens safe checks - b = (b1 | b2) & ei.attacked_by(Them, QUEEN); - if (b) - attackUnits += QueenCheckBonus * count_1s_max_15(b); - - // Enemy knights safe checks - b = pos.attacks_from(ksq) & ei.attacked_by(Them, KNIGHT) & safe; - if (b) - attackUnits += KnightCheckBonus * count_1s_max_15(b); - - // Analyse discovered checks (only for non-pawns right now, consider - // adding pawns later). - b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN); - 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; - - // Ensure that attackUnits is between 0 and 99, in order to avoid array - // out of bounds errors. - attackUnits = Min(99, Max(0, attackUnits)); - - // Finally, extract the king danger score from the KingDangerTable[] array. - // Subtract the score from evaluation, and set ei.futilityMargin[]. - // The reason for storing the king danger score to futility margin - // is that the king danger scores can sometimes be very big, and that - // capturing a single attacking piece can therefore result in a score - // change far bigger than the value of the captured piece. - ei.value -= Sign[Us] * KingDangerTable[Us][attackUnits]; - ei.futilityMargin[Us] = mg_value(KingDangerTable[Us][attackUnits]); + // Enemy bishops safe checks + b = b2 & ei.attacked_by(Them, BISHOP); + if (b) + attackUnits += BishopCheckBonus * count_1s_max_15(b); + + // Enemy knights safe checks + b = pos.attacks_from(ksq) & ei.attacked_by(Them, KNIGHT) & safe; + if (b) + attackUnits += KnightCheckBonus * count_1s_max_15(b); + + // To index KingDangerTable[] attackUnits must be in [0, 99] range + attackUnits = Min(99, Max(0, attackUnits)); + + // Finally, extract the king danger score from the KingDangerTable[] + // array and subtract the score from evaluation. Set also ei.kingDanger[] + // value that will be used for pruning because this value can sometimes + // be very big, and so capturing a single attacking piece can therefore + // result in a score change far bigger than the value of the captured piece. + ei.value -= Sign[Us] * KingDangerTable[Us][attackUnits]; + ei.kingDanger[Us] = mg_value(KingDangerTable[Us][attackUnits]); } } @@ -856,27 +786,27 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); + Bitboard squaresToQueen, defendedSquares, unsafeSquares, supportingPawns; Bitboard b = ei.pi->passed_pawns() & pos.pieces_of_color(Us); while (b) { Square s = pop_1st_bit(&b); - assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN)); assert(pos.pawn_is_passed(Us, s)); int r = int(relative_rank(Us, s) - RANK_2); - int tr = Max(0, r * (r - 1)); + int tr = r * (r - 1); // 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) { Square blockSq = s + pawn_push(Us); + // Adjust bonus based on kings proximity ebonus -= Value(square_distance(pos.king_square(Us), blockSq) * 3 * tr); ebonus -= Value(square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * 1 * tr); ebonus += Value(square_distance(pos.king_square(Them), blockSq) * 6 * tr); @@ -884,47 +814,42 @@ namespace { // If the pawn is free to advance, increase bonus if (pos.square_is_empty(blockSq)) { - // There are no enemy pawns in the pawn's path - Bitboard b2 = squares_in_front_of(Us, s); - - assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB); - - // Squares attacked by us - Bitboard b4 = b2 & ei.attacked_by(Us); - - // Squares attacked or occupied by enemy pieces - Bitboard b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); + squaresToQueen = squares_in_front_of(Us, s); + defendedSquares = squaresToQueen & 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. + // add all X-ray attacks by the rook or queen. Otherwise consider only + // the squares in the pawn's path attacked or occupied by the enemy. if ( (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them)) - && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from(s))) - b3 = b2; - - // Are any of the squares in the pawn's path attacked or occupied by the enemy? - if (b3 == EmptyBoardBB) - // No enemy attacks or pieces, huge bonus! - // Even bigger if we protect the pawn's path - ebonus += Value(tr * (b2 == b4 ? 17 : 15)); + && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from(s))) + unsafeSquares = squaresToQueen; + else + unsafeSquares = squaresToQueen & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); + + // If there aren't enemy attacks or pieces along the path to queen give + // huge bonus. Even bigger if we protect the pawn's path. + if (!unsafeSquares) + ebonus += Value(tr * (squaresToQueen == defendedSquares ? 17 : 15)); else // OK, there are enemy attacks or pieces (but not pawns). 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)); + ebonus += Value(tr * ((unsafeSquares & defendedSquares) == unsafeSquares ? 13 : 8)); // 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) + if (!(squaresToQueen & pos.pieces_of_color(Us))) ebonus += Value(tr); } } // tr != 0 - // If the pawn is supported by a friendly pawn, increase bonus - Bitboard b1 = pos.pieces(PAWN, Us) & neighboring_files_bb(s); - if (b1 & rank_bb(s)) + // Increase the bonus if the passed pawn is supported by a friendly pawn + // on the same rank and a bit smaller if it's on the previous rank. + supportingPawns = pos.pieces(PAWN, Us) & neighboring_files_bb(s); + if (supportingPawns & rank_bb(s)) ebonus += Value(r * 20); - else if (pos.attacks_from(s, Them) & b1) + else if (supportingPawns & rank_bb(s - pawn_push(Us))) ebonus += Value(r * 12); // Rook pawns are a special case: They are sometimes worse, and @@ -935,8 +860,7 @@ namespace { // 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) + if (pos.non_pawn_material(Them) <= KnightValueMidgame) ebonus += ebonus / 4; else if (pos.pieces(ROOK, QUEEN, Them)) ebonus -= ebonus / 4; @@ -969,16 +893,20 @@ namespace { Square s = pop_1st_bit(&b); Square queeningSquare = relative_square(c, make_square(square_file(s), RANK_8)); int d = square_distance(s, queeningSquare) + - int(relative_rank(c, s) == RANK_2) // Double pawn push - square_distance(pos.king_square(opposite_color(c)), queeningSquare) + int(c != pos.side_to_move()); - if (d < 0) + // Do we protect the path to queening ? + bool pathDefended = (ei.attacked_by(c) & squares_in_front_of(c, s)) == squares_in_front_of(c, s); + + if (d < 0 || pathDefended) { - int mtg = RANK_8 - relative_rank(c, s); + int mtg = RANK_8 - relative_rank(c, s) - int(relative_rank(c, s) == RANK_2); int blockerCount = count_1s_max_15(squares_in_front_of(c, s) & pos.occupied_squares()); mtg += blockerCount; d += blockerCount; - if (d < 0 && (!movesToGo[c] || movesToGo[c] > mtg)) + if ((d < 0 || pathDefended) && (!movesToGo[c] || movesToGo[c] > mtg)) { movesToGo[c] = mtg; pawnToGo[c] = s; @@ -1108,29 +1036,24 @@ namespace { // twice. Finally, the space bonus is scaled by a weight taken from the // material hash table. template - void evaluate_space(const Position& pos, EvalInfo& ei) { + int evaluate_space(const Position& pos, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); // Find the safe squares for our pieces inside the area defined by // SpaceMask[us]. A square is unsafe if it is attacked by an enemy // pawn, or if it is undefended and attacked by an enemy piece. + Bitboard safe = SpaceMask[Us] + & ~pos.pieces(PAWN, Us) + & ~ei.attacked_by(Them, PAWN) + & (ei.attacked_by(Us) | ~ei.attacked_by(Them)); - Bitboard safeSquares = SpaceMask[Us] - & ~pos.pieces(PAWN, 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 behind = pos.pieces(PAWN, Us); + behind |= (Us == WHITE ? behind >> 8 : behind << 8); + behind |= (Us == WHITE ? behind >> 16 : behind << 16); - // Find all squares which are at most three squares behind some friendly - // pawn. - Bitboard behindFriendlyPawns = pos.pieces(PAWN, Us); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 8 : behindFriendlyPawns << 8); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 16 : behindFriendlyPawns << 16); - - int space = count_1s_max_15(safeSquares) - + count_1s_max_15(behindFriendlyPawns & safeSquares); - - ei.value += Sign[Us] * apply_weight(make_score(space * ei.mi->space_weight(), 0), Weights[Space]); + return count_1s_max_15(safe) + count_1s_max_15(behind & safe); } @@ -1141,9 +1064,8 @@ namespace { } - // 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. + // 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(const Score& v, Phase ph, const ScaleFactor sf[]) { @@ -1151,9 +1073,11 @@ namespace { assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE); assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); - Value ev = apply_scale_factor(eg_value(v), sf[(eg_value(v) > Value(0) ? WHITE : BLACK)]); + Value eg = eg_value(v); + ScaleFactor f = sf[eg > VALUE_ZERO ? WHITE : BLACK]; + Value ev = Value((eg * int(f)) / SCALE_FACTOR_NORMAL); - int result = (mg_value(v) * ph + ev * (128 - ph)) / 128; + int result = (mg_value(v) * int(ph) + ev * int(128 - ph)) / 128; return Value(result & ~(GrainSize - 1)); } @@ -1163,17 +1087,11 @@ namespace { Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { - Score uciWeight = make_score(get_option_value_int(mgOpt), get_option_value_int(egOpt)); - - // Convert to integer to prevent overflow - int mg = mg_value(uciWeight); - int eg = eg_value(uciWeight); + // Scale option value from 100 to 256 + int mg = get_option_value_int(mgOpt) * 256 / 100; + int eg = get_option_value_int(egOpt) * 256 / 100; - mg = (mg * 0x100) / 100; - eg = (eg * 0x100) / 100; - mg = (mg * mg_value(internalWeight)) / 0x100; - eg = (eg * eg_value(internalWeight)) / 0x100; - return make_score(mg, eg); + return apply_weight(make_score(mg, eg), internalWeight); } // init_safety() initizes the king safety evaluation, based on UCI @@ -1181,28 +1099,19 @@ namespace { void init_safety() { - int maxSlope = 30; - int peak = 0x500; - double a = 0.4; - double b = 0.0; + const Value MaxSlope = Value(30); + const Value Peak = Value(1280); Value t[100]; // First setup the base table for (int i = 0; i < 100; i++) { - if (i < b) - t[i] = Value(0); - else - t[i] = Value((int)(a * (i - b) * (i - b))); - } + t[i] = Value(int(0.4 * i * i)); - for (int i = 1; i < 100; i++) - { - if (t[i] - t[i - 1] > maxSlope) - t[i] = t[i - 1] + Value(maxSlope); + if (i > 0) + t[i] = Min(t[i], t[i - 1] + MaxSlope); - if (t[i] > Value(peak)) - t[i] = Value(peak); + t[i] = Min(t[i], Peak); } // Then apply the weights and get the final KingDangerTable[] array