X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=9b3c4bc2ef31acd4b77ec58ff2bbae63070c0fcd;hp=925d70ac94216743bc0bb9bcc8653fcf89c5ac7d;hb=28933a580eeb4b9a2d717f06c789a6c13dfef19c;hpb=da34023cfcb856e95d8cbc0b80653ab0ee6af6d6 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 925d70ac..9b3c4bc2 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. @@ -111,8 +112,7 @@ namespace { enum { PawnStructure, PassedPawns, Space, KingSafety }; const struct Weight { int mg, eg; } Weights[] = { - {214, 203}, {193, 262}, {47, 0}, {330, 0} - }; + {214, 203}, {193, 262}, {47, 0}, {330, 0} }; Score operator*(Score s, const Weight& w) { return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); @@ -156,19 +156,26 @@ 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, 33), S(45, 43), S(46, 47), S(72, 107), S(48,118) }, // Minor attacks - { S(0, 0), S(0, 25), S(40, 62), S(40, 59), S( 0, 34), S(35, 48) } // 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(176, 139), S(131, 127), S(217, 218), S(203, 215) - }; + // 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. @@ -177,27 +184,22 @@ namespace { { V(7), V(14), V(37), V(63), V(134), V(189) } }; - // 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( 12, 10), S( 3, 10), S( 1, -8), S(-27,-12), + S(-27,-12), S( 1, -8), S( 3, 10), S( 12, 10) }; - const Score ThreatenedByHangingPawn = S(70, 63); - // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S( 3, 62); - const Score KingOnMany = S( 9,138); - 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(48, 28); - const Score PawnAttackThreat = S(31, 19); - 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 @@ -224,7 +226,7 @@ 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 @@ -317,7 +319,7 @@ 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); @@ -343,15 +345,15 @@ 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); @@ -366,7 +368,7 @@ 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); } @@ -466,7 +468,7 @@ 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)]; } @@ -477,8 +479,8 @@ 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) { @@ -506,10 +508,10 @@ 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 @@ -537,7 +539,7 @@ 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 @@ -553,7 +555,7 @@ namespace { & ~ei.attackedBy[Us][PAWN]; if (b) - score += popcount(b) * PawnAttackThreat; + score += ThreatByPawnPush * popcount(b); if (DoTrace) Trace::add(THREAT, Us, score); @@ -617,7 +619,7 @@ 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; @@ -685,7 +687,7 @@ namespace { // 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) { @@ -718,7 +720,7 @@ 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); @@ -811,10 +813,10 @@ 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 @@ -839,7 +841,7 @@ 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(PAWN, ei.pi->pawns_score() * Weights[PawnStructure]); Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); Trace::add(SPACE, evaluate_space(pos, ei) * Weights[Space] , evaluate_space(pos, ei) * Weights[Space]);