X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=fe020facbf2ac67e4f755872b64ab384f57e309e;hp=3379725c2b193cbeeb519c52664aacdca83ff93f;hb=77fa960f8923ca83ba0391835d50f4230ac6a345;hpb=6a79d5d10eb4313fd71abe249a64aaed6bba1e67 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 3379725c..fe020fac 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. @@ -106,18 +107,6 @@ namespace { Pawns::Entry* pi; }; - - // Evaluation weights, indexed by the corresponding evaluation term - enum { PawnStructure, PassedPawns, Space, KingSafety }; - - const struct Weight { int mg, eg; } Weights[] = { - {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); - } - - #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) @@ -160,33 +149,33 @@ namespace { 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 not attacked. + // 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. + // 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 }; // ThreatByKing[on one/on many] contains bonuses for King attacks on - // pawns or pieces which are not pawn defended. + // 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[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) + S( 9, 10), S( 2, 10), S( 1, -8), S(-20,-12), + S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; // Assorted bonuses and penalties used by evaluation @@ -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); @@ -351,7 +340,7 @@ namespace { if (ei.pi->semiopen_file(Us, file_of(s))) score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))]; - // Penalize when trapped by the king, even more if king cannot castle + // 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) { @@ -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) { @@ -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); @@ -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; @@ -820,8 +809,8 @@ Value Eval::evaluate(const Position& pos) { // 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)); @@ -840,10 +829,10 @@ 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() * Weights[PawnStructure]); + Trace::add(PAWN, ei.pi->pawns_score()); Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); - Trace::add(SPACE, evaluate_space(pos, ei) * Weights[Space] - , evaluate_space(pos, ei) * Weights[Space]); + Trace::add(SPACE, evaluate_space(pos, ei) + , evaluate_space(pos, ei)); Trace::add(TOTAL, score); } @@ -896,13 +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); } }