X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=826e860a5c22d3441424f63fd674c2aaa5b624d1;hp=9c83eb6fe3caf2f3702800fe8e9270271612d320;hb=8de29390f2d2bd31585b93ff46eae3051126f666;hpb=8315620522dd268755f32be792802abb62f7366f diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 9c83eb6f..826e860a 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -2,6 +2,7 @@ Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -32,7 +33,7 @@ namespace { namespace Trace { - enum Term { // First 8 entries are for PieceType + enum Term { // The first 8 entries are for PieceType MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERM_NB }; @@ -88,7 +89,7 @@ namespace { // which attack a square in the kingRing of the enemy king. int kingAttackersCount[COLOR_NB]; - // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the + // kingAttackersWeight[color] is the sum of the "weights" of the pieces of the // given color which attack a square in the kingRing of the enemy king. The // weights of the individual piece types are given by the elements in the // KingAttackWeights array. @@ -106,40 +107,26 @@ namespace { Pawns::Entry* pi; }; - - // Evaluation weights, indexed by the corresponding evaluation term - enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety, Threats }; - - const struct Weight { int mg, eg; } Weights[] = { - {266, 334}, {214, 203}, {193, 262}, {47, 0}, {330, 0}, {404, 241} - }; - - Score operator*(Score s, const Weight& w) { - return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); - } - - #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) // MobilityBonus[PieceType][attacked] contains bonuses for middle and end - // game, indexed by piece type and number of attacked squares not occupied by - // friendly pieces. + // game, indexed by piece type and number of attacked squares in the MobilityArea. const Score MobilityBonus[][32] = { {}, {}, - { S(-70,-52), S(-52,-37), S( -7,-17), S( 0, -6), S( 8, 5), S( 16, 9), // Knights - S( 23, 20), S( 31, 21), S( 36, 22) }, - { S(-49,-44), S(-22,-13), S( 16, 0), S( 27, 11), S( 38, 19), S( 52, 34), // Bishops - S( 56, 44), S( 65, 47), S( 67, 51), S( 73, 56), S( 81, 59), S( 83, 69), - S( 95, 72), S(100, 75) }, - { S(-49,-57), S(-22,-14), S(-10, 18), S( -5, 39), S( -4, 50), S( -2, 58), // Rooks - S( 6, 78), S( 11, 86), S( 17, 92), S( 19,103), S( 26,111), S( 27,115), - S( 36,119), S( 41,121), S( 50,122) }, - { S(-41,-24), S(-26, -8), S( 0, 6), S( 2, 14), S( 12, 27), S( 21, 40), // Queens - S( 22, 45), S( 37, 55), S( 40, 57), S( 43, 63), S( 50, 68), S( 52, 74), - S( 56, 80), S( 66, 84), S( 68, 85), S( 69, 88), S( 71, 92), S( 72, 94), - S( 80, 96), S( 89, 98), S( 94,101), S(102,113), S(106,114), S(107,116), - S(112,125), S(113,127), S(117,137), S(122,143) } + { S(-75,-76), S(-56,-54), S(- 9,-26), S( -2,-10), S( 6, 5), S( 15, 11), // Knights + S( 22, 26), S( 30, 28), S( 36, 29) }, + { S(-48,-58), S(-21,-19), S( 16, -2), S( 26, 12), S( 37, 22), S( 51, 42), // Bishops + S( 54, 54), S( 63, 58), S( 65, 63), S( 71, 70), S( 79, 74), S( 81, 86), + S( 92, 90), S( 97, 94) }, + { S(-56,-78), S(-25,-18), S(-11, 26), S( -5, 55), S( -4, 70), S( -1, 81), // Rooks + S( 8,109), S( 14,120), S( 21,128), S( 23,143), S( 31,154), S( 32,160), + S( 43,165), S( 49,168), S( 59,169) }, + { S(-40,-35), S(-25,-12), S( 2, 7), S( 4, 19), S( 14, 37), S( 24, 55), // Queens + S( 25, 62), S( 40, 76), S( 43, 79), S( 47, 87), S( 54, 94), S( 56,102), + S( 60,111), S( 70,116), S( 72,118), S( 73,122), S( 75,128), S( 77,130), + S( 85,133), S( 94,136), S( 99,140), S(108,157), S(112,158), S(113,161), + S(118,174), S(119,177), S(123,191), S(128,199) } }; // Outpost[knight/bishop][supported by pawn] contains bonuses for knights and @@ -157,48 +144,50 @@ namespace { { S( 8, 2), S(13, 4) } // Bishops }; - // Threat[minor/rook][attacked PieceType] contains + // RookOnFile[semiopen/open] contains bonuses for each rook when there is no + // friendly pawn on the rook file. + const Score RookOnFile[2] = { S(19, 10), S(43, 21) }; + + // ThreatBySafePawn[PieceType] contains bonuses according to which piece + // type is attacked by a pawn which is protected or is not attacked. + const Score ThreatBySafePawn[PIECE_TYPE_NB] = { + S(0, 0), S(0, 0), S(176, 139), S(131, 127), S(217, 218), S(203, 215) }; + + // Threat[by minor/by rook][attacked PieceType] contains // bonuses according to which piece type attacks which one. - // Attacks on lesser pieces which are pawn defended are not considered. - const Score Threat[2][PIECE_TYPE_NB] = { - { S(0, 0), S(0, 32), S(25, 39), S(28, 44), S(42, 98), S(35,105) }, // Minor attacks - { S(0, 0), S(0, 27), S(26, 57), S(26, 57), S( 0, 30), S(23, 51) } // Rook attacks + // Attacks on lesser pieces which are pawn-defended are not considered. + const Score Threat[][PIECE_TYPE_NB] = { + { S(0, 0), S(0, 33), S(45, 43), S(46, 47), S(72,107), S(48,118) }, // by Minor + { S(0, 0), S(0, 25), S(40, 62), S(40, 59), S( 0, 34), S(35, 48) } // by Rook }; - // ThreatenedByPawn[PieceType] contains a penalty according to which piece - // type is attacked by a pawn. - const Score ThreatenedByPawn[PIECE_TYPE_NB] = { - S(0, 0), S(0, 0), S(107, 138), S(84, 122), S(114, 203), S(121, 217) - }; + // ThreatByKing[on one/on many] contains bonuses for King attacks on + // pawns or pieces which are not pawn-defended. + const Score ThreatByKing[2] = { S(3, 62), S(9, 138) }; // Passed[mg/eg][Rank] contains midgame and endgame bonuses for passed pawns. // We don't use a Score because we process the two components independently. const Value Passed[][RANK_NB] = { - { V(0), V( 1), V(34), V(90), V(214), V(328) }, - { V(7), V(14), V(37), V(63), V(134), V(189) } + { V(0), V( 1), V(26), V(68), V(161), V(247) }, + { V(7), V(14), V(38), V(64), V(137), V(193) } }; - // PassedFile[File] contains a bonus according to the file of a passed pawn. - const Score PassedFile[] = { - S( 12, 10), S( 3, 10), S( 1, -8), S(-27, -12), - S(-27, -12), S( 1, -8), S( 3, 10), S( 12, 10) + // PassedFile[File] contains a bonus according to the file of a passed pawn + const Score PassedFile[FILE_NB] = { + S( 9, 10), S( 2, 10), S( 1, -8), S(-20,-12), + S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; - const Score ThreatenedByHangingPawn = S(40, 60); - // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S( 2, 58); - const Score KingOnMany = S( 6,125); - const Score RookOnPawn = S( 7, 27); - const Score RookOnOpenFile = S(43, 21); - const Score RookOnSemiOpenFile = S(19, 10); - const Score BishopPawns = S( 8, 12); - const Score MinorBehindPawn = S(16, 0); - const Score TrappedRook = S(92, 0); - const Score Unstoppable = S( 0, 20); - const Score Hanging = S(31, 26); - const Score PawnAttackThreat = S(20, 20); - const Score Checked = S(20, 20); + const Score MinorBehindPawn = S(16, 0); + const Score BishopPawns = S( 8, 12); + const Score RookOnPawn = S( 7, 27); + const Score TrappedRook = S(92, 0); + const Score Checked = S(20, 20); + const Score ThreatByHangingPawn = S(70, 63); + const Score Hanging = S(48, 28); + const Score ThreatByPawnPush = S(31, 19); + const Score Unstoppable = S( 0, 20); // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only @@ -225,7 +214,7 @@ namespace { const int KnightCheck = 14; - // eval_init() initializes king and attack bitboards for given color + // eval_init() initializes king and attack bitboards for a given color // adding pawn attacks. To be done at the beginning of the evaluation. template @@ -318,7 +307,7 @@ namespace { && (pos.pieces(PAWN) & (s + pawn_push(Us)))) score += MinorBehindPawn; - // Penalty for pawns on same color square of bishop + // Penalty for pawns on the same color square as the bishop if (Pt == BISHOP) score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); @@ -344,15 +333,15 @@ namespace { { Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; if (alignedPawns) - score += popcount(alignedPawns) * RookOnPawn; + score += RookOnPawn * popcount(alignedPawns); } // Bonus when on an open or semi-open file if (ei.pi->semiopen_file(Us, file_of(s))) - score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOnOpenFile : RookOnSemiOpenFile; + score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))]; - // Penalize when trapped by the king, even more if king cannot castle - if (mob <= 3 && !ei.pi->semiopen_file(Us, file_of(s))) + // Penalize when trapped by the king, even more if the king cannot castle + else if (mob <= 3) { Square ksq = pos.square(Us); @@ -367,7 +356,7 @@ namespace { if (DoTrace) Trace::add(Pt, Us, score); - // Recursively call evaluate_pieces() of next piece type until KING excluded + // Recursively call evaluate_pieces() of next piece type until KING is excluded return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } @@ -467,7 +456,7 @@ namespace { } // Finally, extract the king danger score from the KingDanger[] - // array and subtract the score from evaluation. + // array and subtract the score from the evaluation. score -= KingDanger[std::max(std::min(attackUnits, 399), 0)]; } @@ -478,8 +467,8 @@ namespace { } - // evaluate_threats() assigns bonuses according to the type of attacking piece - // and the type of attacked one. + // evaluate_threats() assigns bonuses according to the types of the attacking + // and the attacked pieces. template Score evaluate_threats(const Position& pos, const EvalInfo& ei) { @@ -507,10 +496,10 @@ namespace { safeThreats = (shift_bb(b) | shift_bb(b)) & weak; if (weak ^ safeThreats) - score += ThreatenedByHangingPawn; + score += ThreatByHangingPawn; while (safeThreats) - score += ThreatenedByPawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; + score += ThreatBySafePawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; } // Non-pawn enemies defended by a pawn @@ -538,7 +527,7 @@ namespace { b = weak & ei.attackedBy[Us][KING]; if (b) - score += more_than_one(b) ? KingOnMany : KingOnOne; + score += ThreatByKing[more_than_one(b)]; } // Bonus if some pawns can safely push and attack an enemy piece @@ -554,12 +543,12 @@ namespace { & ~ei.attackedBy[Us][PAWN]; if (b) - score += popcount(b) * PawnAttackThreat; + score += ThreatByPawnPush * popcount(b); if (DoTrace) - Trace::add(THREAT, Us, score * Weights[Threats]); + Trace::add(THREAT, Us, score); - return score * Weights[Threats]; + return score; } @@ -618,7 +607,7 @@ namespace { // assign a smaller bonus if the block square isn't attacked. int k = !unsafeSquares ? 18 : !(unsafeSquares & blockSq) ? 8 : 0; - // If the path to queen is fully defended, assign a big bonus. + // If the path to the queen is fully defended, assign a big bonus. // Otherwise assign a smaller bonus if the block square is defended. if (defendedSquares == squaresToQueen) k += 6; @@ -626,10 +615,10 @@ namespace { else if (defendedSquares & blockSq) k += 4; - mbonus += k * rr, ebonus += k * rr; + mbonus += k * rr * 3 / 4, ebonus += k * rr; } else if (pos.pieces(Us) & blockSq) - mbonus += rr * 3 + r * 2 + 3, ebonus += rr + r * 2; + mbonus += (rr * 3 + r * 2 + 3) * 3 / 4, ebonus += rr + r * 2; } // rr != 0 if (pos.count(Us) < pos.count(Them)) @@ -639,10 +628,10 @@ namespace { } if (DoTrace) - Trace::add(PASSED, Us, score * Weights[PassedPawns]); + Trace::add(PASSED, Us, score); // Add the scores to the middlegame and endgame eval - return score * Weights[PassedPawns]; + return score; } @@ -681,12 +670,12 @@ namespace { int weight = pos.count(Us) + pos.count(Us) + pos.count(Them) + pos.count(Them); - return make_score(bonus * weight * weight, 0); + return make_score(bonus * weight * weight * 2 / 11, 0); } // evaluate_initiative() computes the initiative correction value for the - // position, i.e. second order bonus/malus based on the known attacking/defending + // position, i.e., second order bonus/malus based on the known attacking/defending // status of the players. Score evaluate_initiative(const Position& pos, int asymmetry, Value eg) { @@ -706,9 +695,9 @@ namespace { // evaluate_scale_factor() computes the scale factor for the winning side - ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Score score) { + ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Value eg) { - Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK; + Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK; ScaleFactor sf = ei.me->scale_factor(pos, strongSide); // If we don't already have an unusual scale factor, check for certain @@ -719,7 +708,7 @@ namespace { if (pos.opposite_bishops()) { // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) - // is almost a draw, in case of KBP vs KB is even more a draw. + // is almost a draw, in case of KBP vs KB, it is even more a draw. if ( pos.non_pawn_material(WHITE) == BishopValueMg && pos.non_pawn_material(BLACK) == BishopValueMg) sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(31) : ScaleFactor(9); @@ -731,7 +720,7 @@ namespace { } // Endings where weaker side can place his king in front of the opponent's // pawns are drawish. - else if ( abs(eg_value(score)) <= BishopValueEg + else if ( abs(eg) <= BishopValueEg && ei.pi->pawn_span(strongSide) <= 1 && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37); @@ -752,7 +741,7 @@ Value Eval::evaluate(const Position& pos) { assert(!pos.checkers()); EvalInfo ei; - Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; + Score score, mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; // Initialize score by reading the incrementally updated scores included in // the position object (material + piece square tables). Score is computed @@ -770,7 +759,7 @@ Value Eval::evaluate(const Position& pos) { // Probe the pawn hash table ei.pi = Pawns::probe(pos); - score += ei.pi->pawns_score() * Weights[PawnStructure]; + score += ei.pi->pawns_score(); // Initialize attack and king safety bitboards ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; @@ -792,7 +781,7 @@ Value Eval::evaluate(const Position& pos) { // Evaluate all pieces but king and pawns score += evaluate_pieces(pos, ei, mobility, mobilityArea); - score += (mobility[WHITE] - mobility[BLACK]) * Weights[Mobility]; + score += mobility[WHITE] - mobility[BLACK]; // Evaluate kings after all other pieces because we need full attack // information when computing the king safety evaluation. @@ -812,22 +801,22 @@ Value Eval::evaluate(const Position& pos) { { Bitboard b; if ((b = ei.pi->passed_pawns(WHITE)) != 0) - score += int(relative_rank(WHITE, frontmost_sq(WHITE, b))) * Unstoppable; + score += Unstoppable * int(relative_rank(WHITE, frontmost_sq(WHITE, b))); if ((b = ei.pi->passed_pawns(BLACK)) != 0) - score -= int(relative_rank(BLACK, frontmost_sq(BLACK, b))) * Unstoppable; + score -= Unstoppable * int(relative_rank(BLACK, frontmost_sq(BLACK, b))); } // Evaluate space for both sides, only during opening if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222) - score += ( evaluate_space(pos, ei) - - evaluate_space(pos, ei)) * Weights[Space]; + score += evaluate_space(pos, ei) + - evaluate_space(pos, ei); // Evaluate position potential for the winning side score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score)); // Evaluate scale factor for the winning side - ScaleFactor sf = evaluate_scale_factor(pos, ei, score); + ScaleFactor sf = evaluate_scale_factor(pos, ei, eg_value(score)); // Interpolate between a middlegame and a (scaled by 'sf') endgame score Value v = mg_value(score) * int(ei.me->game_phase()) @@ -841,10 +830,9 @@ Value Eval::evaluate(const Position& pos) { Trace::add(MATERIAL, pos.psq_score()); Trace::add(IMBALANCE, ei.me->imbalance()); Trace::add(PAWN, ei.pi->pawns_score()); - Trace::add(MOBILITY, mobility[WHITE] * Weights[Mobility] - , mobility[BLACK] * Weights[Mobility]); - Trace::add(SPACE, evaluate_space(pos, ei) * Weights[Space] - , evaluate_space(pos, ei) * Weights[Space]); + Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); + Trace::add(SPACE, evaluate_space(pos, ei) + , evaluate_space(pos, ei)); Trace::add(TOTAL, score); } @@ -897,13 +885,13 @@ std::string Eval::trace(const Position& pos) { void Eval::init() { - const int MaxSlope = 8700; - const int Peak = 1280000; + const int MaxSlope = 322; + const int Peak = 47410; int t = 0; for (int i = 0; i < 400; ++i) { - t = std::min(Peak, std::min(i * i * 27, t + MaxSlope)); - KingDanger[i] = make_score(t / 1000, 0) * Weights[KingSafety]; + t = std::min(Peak, std::min(i * i - 16, t + MaxSlope)); + KingDanger[i] = make_score(t * 268 / 7700, 0); } }