X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=fa3b0a720b2face4a2ac66d6085370f3b8e77e43;hp=3095838820632331b5f5ac805dd5ed867af83cf9;hb=66ce8ad5fd0e67904ca96dd9ac58f2e512a1f380;hpb=057d710fc2f23b63b574122f2609e03f58d2e494 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 30958388..fa3b0a72 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -2,7 +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 + Copyright (C) 2015-2018 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 @@ -31,10 +31,21 @@ namespace { + const Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB); + const Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; + const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; + const Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; + + const Bitboard KingFlank[FILE_NB] = { + QueenSide, QueenSide, QueenSide, CenterFiles, CenterFiles, KingSide, KingSide, KingSide + }; + namespace Trace { + enum Tracing {NO_TRACE, TRACE}; + enum Term { // The first 8 entries are for PieceType - MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERM_NB + MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, INITIATIVE, TOTAL, TERM_NB }; double scores[TERM_NB][COLOR_NB][PHASE_NB]; @@ -52,7 +63,7 @@ namespace { std::ostream& operator<<(std::ostream& os, Term t) { - if (t == MATERIAL || t == IMBALANCE || t == Term(PAWN) || t == TOTAL) + if (t == MATERIAL || t == IMBALANCE || t == Term(PAWN) || t == INITIATIVE || t == TOTAL) os << " --- --- | --- --- | "; else os << std::setw(5) << scores[t][WHITE][MG] << " " @@ -69,12 +80,39 @@ namespace { using namespace Trace; - // Struct EvalInfo contains various information computed and collected + // Evaluation class contains various information computed and collected // by the evaluation functions. - struct EvalInfo { + template + class Evaluation { + + public: + Evaluation() = delete; + Evaluation(const Position& p) : pos(p) {} + Evaluation& operator=(const Evaluation&) = delete; + + Value value(); + + private: + // Evaluation helpers (used when calling value()) + template void initialize(); + template Score evaluate_king(); + template Score evaluate_threats(); + template Score evaluate_passed_pawns(); + template Score evaluate_space(); + template Score evaluate_pieces(); + ScaleFactor evaluate_scale_factor(Value eg); + Score evaluate_initiative(Value eg); + + // Data members + const Position& pos; + Material::Entry* me; + Pawns::Entry* pe; + Bitboard mobilityArea[COLOR_NB]; + Score mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; // attackedBy[color][piece type] is a bitboard representing all squares - // attacked by a given color and piece type (can be also ALL_PIECES). + // attacked by a given color and piece type. Special "piece types" which are + // also calculated are QUEEN_DIAGONAL and ALL_PIECES. Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB]; // attackedBy2[color] are the squares attacked by 2 pieces of a given color, @@ -84,7 +122,7 @@ namespace { // kingRing[color] is the zone around the king which is considered // by the king safety evaluation. This consists of the squares directly - // adjacent to the king, and the three (or two, for a king on an edge file) + // adjacent to the king, and (only for a king on its first rank) the // squares two ranks in front of the king. For instance, if black's king // is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8, // f7, g7, h7, f6, g6 and h6. @@ -106,69 +144,56 @@ namespace { // a white knight on g5 and black's king is on g8, this white knight adds 2 // to kingAdjacentZoneAttacksCount[WHITE]. int kingAdjacentZoneAttacksCount[COLOR_NB]; - - Bitboard pinnedPieces[COLOR_NB]; - Material::Entry* me; - Pawns::Entry* pi; }; #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 in the MobilityArea. + // MobilityBonus[PieceType-2][attacked] contains bonuses for middle and end game, + // indexed by piece type and number of attacked squares in the mobility area. const Score MobilityBonus[][32] = { - {}, {}, - { 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) } + { S(-75,-76), S(-57,-54), S( -9,-28), S( -2,-10), S( 6, 5), S( 14, 12), // Knights + S( 22, 26), S( 29, 29), S( 36, 29) }, + { S(-48,-59), S(-20,-23), S( 16, -3), S( 26, 13), S( 38, 24), S( 51, 42), // Bishops + S( 55, 54), S( 63, 57), S( 63, 65), S( 68, 73), S( 81, 78), S( 81, 86), + S( 91, 88), S( 98, 97) }, + { S(-58,-76), S(-27,-18), S(-15, 28), S(-10, 55), S( -5, 69), S( -2, 82), // Rooks + S( 9,112), S( 16,118), S( 30,132), S( 29,142), S( 32,155), S( 38,165), + S( 46,166), S( 48,169), S( 58,171) }, + { S(-39,-36), S(-21,-15), S( 3, 8), S( 3, 18), S( 14, 34), S( 22, 54), // Queens + S( 28, 61), S( 41, 73), S( 43, 79), S( 48, 92), S( 56, 94), S( 60,104), + S( 60,113), S( 66,120), S( 67,123), S( 70,126), S( 71,133), S( 73,136), + S( 79,140), S( 88,143), S( 88,148), S( 99,166), S(102,170), S(102,175), + S(106,184), S(109,191), S(113,206), S(116,212) } }; - // Outpost[knight/bishop][supported by pawn] contains bonuses for knights and - // bishops outposts, bigger if outpost piece is supported by a pawn. + // Outpost[knight/bishop][supported by pawn] contains bonuses for minor + // pieces if they can reach an outpost square, bigger if that square is + // supported by a pawn. If the minor piece occupies an outpost square + // then score is doubled. const Score Outpost[][2] = { - { S(43,11), S(65,20) }, // Knights - { S(20, 3), S(29, 8) } // Bishops - }; - - // ReachableOutpost[knight/bishop][supported by pawn] contains bonuses for - // knights and bishops which can reach an outpost square in one move, bigger - // if outpost square is supported by a pawn. - const Score ReachableOutpost[][2] = { - { S(21, 5), S(35, 8) }, // Knights - { S( 8, 0), S(14, 4) } // Bishops + { S(22, 6), S(36,12) }, // Knight + { S( 9, 2), S(15, 5) } // Bishop }; // RookOnFile[semiopen/open] contains bonuses for each rook when there is no // friendly pawn on the rook file. - const Score RookOnFile[2] = { S(20, 7), S(45, 20) }; - - // 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[][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 + const Score RookOnFile[] = { S(20, 7), S(45, 20) }; + + // ThreatByMinor/ByRook[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 ThreatByMinor[PIECE_TYPE_NB] = { + S(0, 0), S(0, 33), S(45, 43), S(46, 47), S(72, 107), S(48, 118) + }; + + const Score ThreatByRook[PIECE_TYPE_NB] = { + S(0, 0), S(0, 25), S(40, 62), S(40, 59), S(0, 34), S(35, 48) }; - // ThreatByKing[on one/on many] contains bonuses for King attacks on + // 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) }; + const Score ThreatByKing[] = { 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. @@ -180,28 +205,29 @@ namespace { // 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) + S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; + // KingProtector[PieceType-2] contains a bonus according to distance from king + const Score KingProtector[] = { S(-3, -5), S(-4, -3), S(-3, 0), S(-1, 1) }; + // Assorted bonuses and penalties used by evaluation - const Score MinorBehindPawn = S(16, 0); - const Score BishopPawns = S( 8, 12); - const Score RookOnPawn = S( 8, 24); - const Score TrappedRook = S(92, 0); - const Score CloseEnemies = S( 7, 0); - const Score SafeCheck = S(20, 20); - const Score OtherCheck = S(10, 10); - const Score ThreatByHangingPawn = S(71, 61); - const Score LooseEnemies = S( 0, 25); - const Score WeakQueen = S(35, 0); - const Score Hanging = S(48, 27); - const Score ThreatByPawnPush = S(38, 22); - 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 - // happen in Chess960 games. - const Score TrappedBishopA1H1 = S(50, 50); + const Score MinorBehindPawn = S( 16, 0); + const Score BishopPawns = S( 8, 12); + const Score LongRangedBishop = S( 22, 0); + const Score RookOnPawn = S( 8, 24); + const Score TrappedRook = S( 92, 0); + const Score WeakQueen = S( 50, 10); + const Score CloseEnemies = S( 7, 0); + const Score PawnlessFlank = S( 20, 80); + const Score ThreatBySafePawn = S(192,175); + const Score ThreatByRank = S( 16, 3); + const Score Hanging = S( 48, 27); + const Score WeakUnopposedPawn = S( 5, 25); + const Score ThreatByPawnPush = S( 38, 22); + const Score ThreatByAttackOnQueen = S( 38, 22); + const Score HinderPassedPawn = S( 7, 0); + const Score TrappedBishopA1H1 = S( 50, 50); #undef S #undef V @@ -210,99 +236,117 @@ namespace { const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 }; // Penalties for enemy's safe checks - const int QueenContactCheck = 997; - const int QueenCheck = 695; - const int RookCheck = 638; - const int BishopCheck = 538; - const int KnightCheck = 874; + const int QueenSafeCheck = 780; + const int RookSafeCheck = 880; + const int BishopSafeCheck = 435; + const int KnightSafeCheck = 790; + + // Threshold for lazy and space evaluation + const Value LazyThreshold = Value(1500); + const Value SpaceThreshold = Value(12222); - // eval_init() initializes king and attack bitboards for a given color - // adding pawn attacks. To be done at the beginning of the evaluation. + // initialize() computes king and pawn attacks, and the king ring bitboard + // for a given color. This is done at the beginning of the evaluation. - template - void eval_init(const Position& pos, EvalInfo& ei) { + template template + void Evaluation::initialize() { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Direction Up = (Us == WHITE ? NORTH : SOUTH); + const Direction Down = (Us == WHITE ? SOUTH : NORTH); + const Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB); - ei.pinnedPieces[Us] = pos.pinned_pieces(Us); - Bitboard b = ei.attackedBy[Them][KING]; - ei.attackedBy[Them][ALL_PIECES] |= b; - ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); - ei.attackedBy2[Us] = ei.attackedBy[Us][PAWN] & ei.attackedBy[Us][KING]; + // Find our pawns on the first two ranks, and those which are blocked + Bitboard b = pos.pieces(Us, PAWN) & (shift(pos.pieces()) | LowRanks); - // Init king safety tables only if we are going to use them - if (pos.non_pawn_material(Us) >= QueenValueMg) + // Squares occupied by those pawns, by our king, or controlled by enemy pawns + // are excluded from the mobility area. + mobilityArea[Us] = ~(b | pos.square(Us) | pe->pawn_attacks(Them)); + + // Initialise the attack bitboards with the king and pawn information + b = attackedBy[Us][KING] = pos.attacks_from(pos.square(Us)); + attackedBy[Us][PAWN] = pe->pawn_attacks(Us); + + attackedBy2[Us] = b & attackedBy[Us][PAWN]; + attackedBy[Us][ALL_PIECES] = b | attackedBy[Us][PAWN]; + + // Init our king safety tables only if we are going to use them + if (pos.non_pawn_material(Them) >= RookValueMg + KnightValueMg) { - ei.kingRing[Them] = b | shift_bb(b); - b &= ei.attackedBy[Us][PAWN]; - ei.kingAttackersCount[Us] = popcount(b); - ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0; + kingRing[Us] = b; + if (relative_rank(Us, pos.square(Us)) == RANK_1) + kingRing[Us] |= shift(b); + + kingAttackersCount[Them] = popcount(b & pe->pawn_attacks(Them)); + kingAdjacentZoneAttacksCount[Them] = kingAttackersWeight[Them] = 0; } else - ei.kingRing[Them] = ei.kingAttackersCount[Us] = 0; + kingRing[Us] = kingAttackersCount[Them] = 0; } // evaluate_pieces() assigns bonuses and penalties to the pieces of a given // color and type. - template - Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, - const Bitboard* mobilityArea) { - Bitboard b, bb; - Square s; - Score score = SCORE_ZERO; + template template + Score Evaluation::evaluate_pieces() { - const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Color Them = (Us == WHITE ? BLACK : WHITE); const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); - ei.attackedBy[Us][Pt] = 0; + Bitboard b, bb; + Square s; + Score score = SCORE_ZERO; + + attackedBy[Us][Pt] = 0; + + if (Pt == QUEEN) + attackedBy[Us][QUEEN_DIAGONAL] = 0; while ((s = *pl++) != SQ_NONE) { // Find attacked squares, including x-ray attacks for bishops and rooks - b = Pt == BISHOP ? attacks_bb(s, pos.pieces() ^ pos.pieces(Us, QUEEN)) - : Pt == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN)) + b = Pt == BISHOP ? attacks_bb(s, pos.pieces() ^ pos.pieces(QUEEN)) + : Pt == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(QUEEN) ^ pos.pieces(Us, ROOK)) : pos.attacks_from(s); - if (ei.pinnedPieces[Us] & s) + if (pos.pinned_pieces(Us) & s) b &= LineBB[pos.square(Us)][s]; - ei.attackedBy2[Us] |= ei.attackedBy[Us][ALL_PIECES] & b; - ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; + attackedBy2[Us] |= attackedBy[Us][ALL_PIECES] & b; + attackedBy[Us][ALL_PIECES] |= attackedBy[Us][Pt] |= b; + + if (Pt == QUEEN) + attackedBy[Us][QUEEN_DIAGONAL] |= b & PseudoAttacks[BISHOP][s]; - if (b & ei.kingRing[Them]) + if (b & kingRing[Them]) { - ei.kingAttackersCount[Us]++; - ei.kingAttackersWeight[Us] += KingAttackWeights[Pt]; - ei.kingAdjacentZoneAttacksCount[Us] += popcount(b & ei.attackedBy[Them][KING]); + kingAttackersCount[Us]++; + kingAttackersWeight[Us] += KingAttackWeights[Pt]; + kingAdjacentZoneAttacksCount[Us] += popcount(b & attackedBy[Them][KING]); } - if (Pt == QUEEN) - b &= ~( ei.attackedBy[Them][KNIGHT] - | ei.attackedBy[Them][BISHOP] - | ei.attackedBy[Them][ROOK]); - int mob = popcount(b & mobilityArea[Us]); - mobility[Us] += MobilityBonus[Pt][mob]; + mobility[Us] += MobilityBonus[Pt - 2][mob]; + + // Bonus for this piece as a king protector + score += KingProtector[Pt - 2] * distance(s, pos.square(Us)); if (Pt == BISHOP || Pt == KNIGHT) { // Bonus for outpost squares - bb = OutpostRanks & ~ei.pi->pawn_attacks_span(Them); + bb = OutpostRanks & ~pe->pawn_attacks_span(Them); if (bb & s) - score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)]; + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & s)] * 2; else { bb &= b & ~pos.pieces(Us); if (bb) - score += ReachableOutpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & bb)]; + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)]; } // Bonus when behind a pawn @@ -310,9 +354,15 @@ namespace { && (pos.pieces(PAWN) & (s + pawn_push(Us)))) score += MinorBehindPawn; - // 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); + { + // Penalty for pawns on the same color square as the bishop + score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s); + + // Bonus for bishop on a long diagonal which can "see" both center squares + if (more_than_one(Center & (attacks_bb(s, pos.pieces(PAWN)) | s))) + score += LongRangedBishop; + } // An important Chess960 pattern: A cornered bishop blocked by a friendly // pawn diagonally in front of it is a very serious problem, especially @@ -321,7 +371,7 @@ namespace { && pos.is_chess960() && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) { - Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); + Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST); if (pos.piece_on(s + d) == make_piece(Us, PAWN)) score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 @@ -336,17 +386,16 @@ namespace { score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]); // Bonus when on an open or semi-open file - if (ei.pi->semiopen_file(Us, file_of(s))) - score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))]; + if (pe->semiopen_file(Us, file_of(s))) + score += RookOnFile[bool(pe->semiopen_file(Them, file_of(s)))]; - // Penalize when trapped by the king, even more if the king cannot castle + // Penalty when trapped by the king, even more if the king cannot castle else if (mob <= 3) { Square ksq = pos.square(Us); if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) - && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) - && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + && !pe->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); } } @@ -360,128 +409,91 @@ namespace { } } - if (DoTrace) + if (T) Trace::add(Pt, Us, score); - // Recursively call evaluate_pieces() of next piece type until KING is excluded - return score - evaluate_pieces(pos, ei, mobility, mobilityArea); + return score; } - template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } - template<> - Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } - // evaluate_king() assigns bonuses and penalties to a king of a given color - const Bitboard WhiteCamp = Rank1BB | Rank2BB | Rank3BB | Rank4BB | Rank5BB; - const Bitboard BlackCamp = Rank8BB | Rank7BB | Rank6BB | Rank5BB | Rank4BB; - const Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; - const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; - const Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; - - const Bitboard KingFlank[COLOR_NB][FILE_NB] = { - { QueenSide & WhiteCamp, QueenSide & WhiteCamp, QueenSide & WhiteCamp, CenterFiles & WhiteCamp, - CenterFiles & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp }, - { QueenSide & BlackCamp, QueenSide & BlackCamp, QueenSide & BlackCamp, CenterFiles & BlackCamp, - CenterFiles & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp }, - }; - - template - Score evaluate_king(const Position& pos, const EvalInfo& ei) { + template template + Score Evaluation::evaluate_king() { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? DELTA_N : DELTA_S); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB + : AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB); - Bitboard undefended, b, b1, b2, safe, other; - int kingDanger; const Square ksq = pos.square(Us); + Bitboard weak, b, b1, b2, safe, unsafeChecks; // King shelter and enemy pawns storm - Score score = ei.pi->king_safety(pos, ksq); + Score score = pe->king_safety(pos, ksq); // Main king safety evaluation - if (ei.kingAttackersCount[Them]) + if (kingAttackersCount[Them] > (1 - pos.count(Them))) { - // Find the attacked squares which are defended only by the king... - undefended = ei.attackedBy[Them][ALL_PIECES] - & ei.attackedBy[Us][KING] - & ~ei.attackedBy2[Us]; - - // ... and those which are not defended at all in the larger king ring - b = ei.attackedBy[Them][ALL_PIECES] & ~ei.attackedBy[Us][ALL_PIECES] - & ei.kingRing[Us] & ~pos.pieces(Them); - - // Initialize the 'kingDanger' variable, which will be transformed - // later into a king danger score. 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 and the quality of - // the pawn shelter (current 'score' value). - kingDanger = std::min(807, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) - + 101 * ei.kingAdjacentZoneAttacksCount[Them] - + 235 * popcount(undefended) - + 134 * (popcount(b) + !!ei.pinnedPieces[Us]) - - 717 * !pos.count(Them) - - 7 * mg_value(score) / 5 - 5; - - // Analyse the enemy's safe queen contact checks. Firstly, find the - // undefended squares around the king reachable by the enemy queen... - b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them); - - // ...and keep squares supported by another enemy piece - kingDanger += QueenContactCheck * popcount(b & ei.attackedBy2[Them]); - - // Analyse the safe enemy's checks which are possible on next move... - safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - - // ... and some other potential checks, only requiring the square to be - // safe from pawn-attacks, and not being occupied by a blocked pawn. - other = ~( ei.attackedBy[Us][PAWN] - | (pos.pieces(Them, PAWN) & shift_bb(pos.pieces(PAWN)))); - - b1 = pos.attacks_from(ksq); - b2 = pos.attacks_from(ksq); - - // Enemy queen safe checks - if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe) - kingDanger += QueenCheck, score -= SafeCheck; - - // For other pieces, also consider the square safe if attacked twice, - // and only defended by a queen. - safe |= ei.attackedBy2[Them] - & ~(ei.attackedBy2[Us] | pos.pieces(Them)) - & ei.attackedBy[Us][QUEEN]; - - // Enemy rooks safe and other checks - if (b1 & ei.attackedBy[Them][ROOK] & safe) - kingDanger += RookCheck, score -= SafeCheck; + // Attacked squares defended at most once by our queen or king + weak = attackedBy[Them][ALL_PIECES] + & ~attackedBy2[Us] + & (attackedBy[Us][KING] | attackedBy[Us][QUEEN] | ~attackedBy[Us][ALL_PIECES]); - else if (b1 & ei.attackedBy[Them][ROOK] & other) - score -= OtherCheck; + int kingDanger = unsafeChecks = 0; - // Enemy bishops safe and other checks - if (b2 & ei.attackedBy[Them][BISHOP] & safe) - kingDanger += BishopCheck, score -= SafeCheck; + // Analyse the safe enemy's checks which are possible on next move + safe = ~pos.pieces(Them); + safe &= ~attackedBy[Us][ALL_PIECES] | (weak & attackedBy2[Them]); - else if (b2 & ei.attackedBy[Them][BISHOP] & other) - score -= OtherCheck; + b1 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN)); + b2 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN)); - // Enemy knights safe and other checks - b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT]; + // Enemy queen safe checks + if ((b1 | b2) & attackedBy[Them][QUEEN] & safe & ~attackedBy[Us][QUEEN]) + kingDanger += QueenSafeCheck; + + b1 &= attackedBy[Them][ROOK]; + b2 &= attackedBy[Them][BISHOP]; + + // Enemy rooks checks + if (b1 & safe) + kingDanger += RookSafeCheck; + else + unsafeChecks |= b1; + + // Enemy bishops checks + if (b2 & safe) + kingDanger += BishopSafeCheck; + else + unsafeChecks |= b2; + + // Enemy knights checks + b = pos.attacks_from(ksq) & attackedBy[Them][KNIGHT]; if (b & safe) - kingDanger += KnightCheck, score -= SafeCheck; - - else if (b & other) - score -= OtherCheck; - - // Compute the king danger score and subtract it from the evaluation + kingDanger += KnightSafeCheck; + else + unsafeChecks |= b; + + // Unsafe or occupied checking squares will also be considered, as long as + // the square is in the attacker's mobility area. + unsafeChecks &= mobilityArea[Them]; + + kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them] + + 102 * kingAdjacentZoneAttacksCount[Them] + + 191 * popcount(kingRing[Us] & weak) + + 143 * popcount(pos.pinned_pieces(Us) | unsafeChecks) + - 848 * !pos.count(Them) + - 9 * mg_value(score) / 8 + + 40; + + // Transform the kingDanger units into a Score, and substract it from the evaluation if (kingDanger > 0) - score -= make_score(std::min(kingDanger * kingDanger / 4096, 2 * int(BishopValueMg)), 0); + score -= make_score(kingDanger * kingDanger / 4096, kingDanger / 16); } // King tropism: firstly, find squares that opponent attacks in our king flank - b = ei.attackedBy[Them][ALL_PIECES] & KingFlank[Us][file_of(ksq)]; + File kf = file_of(ksq); + b = attackedBy[Them][ALL_PIECES] & KingFlank[kf] & Camp; assert(((Us == WHITE ? b << 4 : b >> 4) & b) == 0); assert(popcount(Us == WHITE ? b << 4 : b >> 4) == popcount(b)); @@ -489,11 +501,15 @@ namespace { // Secondly, add the squares which are attacked twice in that flank and // which are not defended by our pawns. b = (Us == WHITE ? b << 4 : b >> 4) - | (b & ei.attackedBy2[Them] & ~ei.attackedBy[Us][PAWN]); + | (b & attackedBy2[Them] & ~attackedBy[Us][PAWN]); score -= CloseEnemies * popcount(b); - if (DoTrace) + // Penalty when our king is on a pawnless flank + if (!(pos.pieces(PAWN) & KingFlank[kf])) + score -= PawnlessFlank; + + if (T) Trace::add(KING, Us, score); return score; @@ -503,108 +519,128 @@ namespace { // 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) { - - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? DELTA_N : DELTA_S); - const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE); - const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW); - const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); - const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + template template + Score Evaluation::evaluate_threats() { - enum { Minor, Rook }; + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Direction Up = (Us == WHITE ? NORTH : SOUTH); + const Direction Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); + const Direction Right = (Us == WHITE ? NORTH_EAST : SOUTH_WEST); + const Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - Bitboard b, weak, defended, safeThreats; + Bitboard b, weak, defended, stronglyProtected, safeThreats; Score score = SCORE_ZERO; - // Small bonus if the opponent has loose pawns or pieces - if ( (pos.pieces(Them) ^ pos.pieces(Them, QUEEN, KING)) - & ~(ei.attackedBy[Us][ALL_PIECES] | ei.attackedBy[Them][ALL_PIECES])) - score += LooseEnemies; - // Non-pawn enemies attacked by a pawn - weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN]; + weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & attackedBy[Us][PAWN]; if (weak) { - b = pos.pieces(Us, PAWN) & ( ~ei.attackedBy[Them][ALL_PIECES] - | ei.attackedBy[Us][ALL_PIECES]); - - safeThreats = (shift_bb(b) | shift_bb(b)) & weak; + b = pos.pieces(Us, PAWN) & ( ~attackedBy[Them][ALL_PIECES] + | attackedBy[Us][ALL_PIECES]); - if (weak ^ safeThreats) - score += ThreatByHangingPawn; + safeThreats = (shift(b) | shift(b)) & weak; - while (safeThreats) - score += ThreatBySafePawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; + score += ThreatBySafePawn * popcount(safeThreats); } - // Non-pawn enemies defended by a pawn - defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Them][PAWN]; + // Squares strongly protected by the opponent, either because they attack the + // square with a pawn, or because they attack the square twice and we don't. + stronglyProtected = attackedBy[Them][PAWN] + | (attackedBy2[Them] & ~attackedBy2[Us]); + + // Non-pawn enemies, strongly protected + defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) + & stronglyProtected; - // Enemies not defended by a pawn and under our attack + // Enemies not strongly protected and under our attack weak = pos.pieces(Them) - & ~ei.attackedBy[Them][PAWN] - & ei.attackedBy[Us][ALL_PIECES]; + & ~stronglyProtected + & attackedBy[Us][ALL_PIECES]; // Add a bonus according to the kind of attacking pieces if (defended | weak) { - b = (defended | weak) & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + b = (defended | weak) & (attackedBy[Us][KNIGHT] | attackedBy[Us][BISHOP]); while (b) - score += Threat[Minor][type_of(pos.piece_on(pop_lsb(&b)))]; + { + Square s = pop_lsb(&b); + score += ThreatByMinor[type_of(pos.piece_on(s))]; + if (type_of(pos.piece_on(s)) != PAWN) + score += ThreatByRank * (int)relative_rank(Them, s); + } - b = (pos.pieces(Them, QUEEN) | weak) & ei.attackedBy[Us][ROOK]; + b = (pos.pieces(Them, QUEEN) | weak) & attackedBy[Us][ROOK]; while (b) - score += Threat[Rook ][type_of(pos.piece_on(pop_lsb(&b)))]; + { + Square s = pop_lsb(&b); + score += ThreatByRook[type_of(pos.piece_on(s))]; + if (type_of(pos.piece_on(s)) != PAWN) + score += ThreatByRank * (int)relative_rank(Them, s); + } - score += Hanging * popcount(weak & ~ei.attackedBy[Them][ALL_PIECES]); + score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]); - b = weak & ei.attackedBy[Us][KING]; + b = weak & attackedBy[Us][KING]; if (b) score += ThreatByKing[more_than_one(b)]; } - // Bonus if some pawns can safely push and attack an enemy piece - b = pos.pieces(Us, PAWN) & ~TRank7BB; - b = shift_bb(b | (shift_bb(b & TRank2BB) & ~pos.pieces())); + // Bonus for opponent unopposed weak pawns + if (pos.pieces(Us, ROOK, QUEEN)) + score += WeakUnopposedPawn * pe->weak_unopposed(Them); + + // Find squares where our pawns can push on the next move + b = shift(pos.pieces(Us, PAWN)) & ~pos.pieces(); + b |= shift(b & TRank3BB) & ~pos.pieces(); - b &= ~pos.pieces() - & ~ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); + // Keep only the squares which are not completely unsafe + b &= ~attackedBy[Them][PAWN] + & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]); - b = (shift_bb(b) | shift_bb(b)) + // Add a bonus for each new pawn threats from those squares + b = (shift(b) | shift(b)) & pos.pieces(Them) - & ~ei.attackedBy[Us][PAWN]; + & ~attackedBy[Us][PAWN]; score += ThreatByPawnPush * popcount(b); - if (DoTrace) + // Add a bonus for safe slider attack threats on opponent queen + safeThreats = ~pos.pieces(Us) & ~attackedBy2[Them] & attackedBy2[Us]; + b = (attackedBy[Us][BISHOP] & attackedBy[Them][QUEEN_DIAGONAL]) + | (attackedBy[Us][ROOK ] & attackedBy[Them][QUEEN] & ~attackedBy[Them][QUEEN_DIAGONAL]); + + score += ThreatByAttackOnQueen * popcount(b & safeThreats); + + if (T) Trace::add(THREAT, Us, score); return score; } - // evaluate_passed_pawns() evaluates the passed pawns of the given color + // evaluate_passed_pawns() evaluates the passed pawns and candidate passed + // pawns of the given color. - template - Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei) { + template template + Score Evaluation::evaluate_passed_pawns() { - const Color Them = (Us == WHITE ? BLACK : WHITE); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Direction Up = (Us == WHITE ? NORTH : SOUTH); - Bitboard b, squaresToQueen, defendedSquares, unsafeSquares; + Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares; Score score = SCORE_ZERO; - b = ei.pi->passed_pawns(Us); + b = pe->passed_pawns(Us); while (b) { Square s = pop_lsb(&b); - assert(pos.pawn_passed(Us, s)); - assert(!(pos.pieces(PAWN) & forward_bb(Us, s))); + assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up))); + + bb = forward_file_bb(Us, s) & (attackedBy[Them][ALL_PIECES] | pos.pieces(Them)); + score -= HinderPassedPawn * popcount(bb); int r = relative_rank(Us, s) - RANK_2; int rr = r * (r - 1); @@ -613,15 +649,15 @@ namespace { if (rr) { - Square blockSq = s + pawn_push(Us); + Square blockSq = s + Up; // Adjust bonus based on the king's proximity ebonus += distance(pos.square(Them), blockSq) * 5 * rr - - distance(pos.square(Us ), blockSq) * 2 * rr; + - distance(pos.square( Us), blockSq) * 2 * rr; // If blockSq is not the queening square then consider also a second push if (relative_rank(Us, blockSq) != RANK_8) - ebonus -= distance(pos.square(Us), blockSq + pawn_push(Us)) * rr; + ebonus -= distance(pos.square(Us), blockSq + Up) * rr; // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -629,15 +665,15 @@ namespace { // If there is a rook or queen attacking/defending the pawn from behind, // consider all the squaresToQueen. Otherwise consider only the squares // in the pawn's path attacked or occupied by the enemy. - defendedSquares = unsafeSquares = squaresToQueen = forward_bb(Us, s); + defendedSquares = unsafeSquares = squaresToQueen = forward_file_bb(Us, s); - Bitboard bb = forward_bb(Them, s) & pos.pieces(ROOK, QUEEN) & pos.attacks_from(s); + bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN) & pos.attacks_from(s); if (!(pos.pieces(Us) & bb)) - defendedSquares &= ei.attackedBy[Us][ALL_PIECES]; + defendedSquares &= attackedBy[Us][ALL_PIECES]; if (!(pos.pieces(Them) & bb)) - unsafeSquares &= ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them); + unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them); // If there aren't any enemy attacks, assign a big bonus. Otherwise // assign a smaller bonus if the block square isn't attacked. @@ -657,13 +693,17 @@ namespace { mbonus += rr + r * 2, ebonus += rr + r * 2; } // rr != 0 + // Scale down bonus for candidate passers which need more than one + // pawn push to become passed or have a pawn in front of them. + if (!pos.pawn_passed(Us, s + Up) || (pos.pieces(PAWN) & forward_file_bb(Us, s))) + mbonus /= 2, ebonus /= 2; + score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; } - if (DoTrace) + if (T) Trace::add(PASSED, Us, score); - // Add the scores to the middlegame and endgame eval return score; } @@ -674,21 +714,22 @@ namespace { // squares one, two or three squares behind a friendly pawn are counted // twice. Finally, the space bonus is multiplied by a weight. The aim is to // improve play on game opening. - template - Score evaluate_space(const Position& pos, const EvalInfo& ei) { + + template template + Score Evaluation::evaluate_space() { const Color Them = (Us == WHITE ? BLACK : WHITE); const Bitboard SpaceMask = - Us == WHITE ? (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank2BB | Rank3BB | Rank4BB) - : (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank7BB | Rank6BB | Rank5BB); + Us == WHITE ? CenterFiles & (Rank2BB | Rank3BB | Rank4BB) + : CenterFiles & (Rank7BB | Rank6BB | Rank5BB); // Find the safe squares for our pieces inside the area defined by // SpaceMask. 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 & ~pos.pieces(Us, PAWN) - & ~ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); + & ~attackedBy[Them][PAWN] + & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]); // Find all squares which are at most three squares behind some friendly pawn Bitboard behind = pos.pieces(Us, PAWN); @@ -698,46 +739,51 @@ namespace { // Since SpaceMask[Us] is fully on our half of the board... assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); - // ...count safe + (behind & safe) with a single popcount + // ...count safe + (behind & safe) with a single popcount. int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); - bonus = std::min(16, bonus); - int weight = pos.count(Us) - 2 * ei.pi->open_files(); + int weight = pos.count(Us) - 2 * pe->open_files(); - return make_score(bonus * weight * weight / 18, 0); + return make_score(bonus * weight * weight / 16, 0); } // evaluate_initiative() computes the initiative correction value for the // 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) { + + template + Score Evaluation::evaluate_initiative(Value eg) { int kingDistance = distance(pos.square(WHITE), pos.square(BLACK)) - distance(pos.square(WHITE), pos.square(BLACK)); - int pawns = pos.count(WHITE) + pos.count(BLACK); + bool bothFlanks = (pos.pieces(PAWN) & QueenSide) && (pos.pieces(PAWN) & KingSide); // Compute the initiative bonus for the attacking side - int initiative = 8 * (asymmetry + kingDistance - 15) + 12 * pawns; + int initiative = 8 * (pe->pawn_asymmetry() + kingDistance - 17) + 12 * pos.count() + 16 * bothFlanks; // Now apply the bonus: note that we find the attacking side by extracting // the sign of the endgame value, and that we carefully cap the bonus so - // that the endgame score will never be divided by more than two. - int value = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg / 2)); + // that the endgame score will never change sign after the bonus. + int v = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg)); + + if (T) + Trace::add(INITIATIVE, make_score(0, v)); - return make_score(0, value); + return make_score(0, v); } // evaluate_scale_factor() computes the scale factor for the winning side - ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Value eg) { + + template + ScaleFactor Evaluation::evaluate_scale_factor(Value eg) { Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK; - ScaleFactor sf = ei.me->scale_factor(pos, strongSide); + ScaleFactor sf = me->scale_factor(pos, strongSide); // If we don't already have an unusual scale factor, check for certain // types of endgames, and use a lower scale for those. - if ( ei.me->game_phase() < PHASE_MIDGAME - && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) + if (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN) { if (pos.opposite_bishops()) { @@ -745,139 +791,116 @@ namespace { // 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); + return more_than_one(pos.pieces(PAWN)) ? ScaleFactor(31) : ScaleFactor(9); // Endgame with opposite-colored bishops, but also other pieces. Still // a bit drawish, but not as drawish as with only the two bishops. - else - sf = ScaleFactor(46); + return ScaleFactor(46); } // Endings where weaker side can place his king in front of the opponent's // pawns are drawish. else if ( abs(eg) <= BishopValueEg && pos.count(strongSide) <= 2 && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) - sf = ScaleFactor(37 + 7 * pos.count(strongSide)); + return ScaleFactor(37 + 7 * pos.count(strongSide)); } return sf; } -} // namespace + // value() is the main function of the class. It computes the various parts of + // the evaluation and returns the value of the position from the point of view + // of the side to move. -/// evaluate() is the main evaluation function. It returns a static evaluation -/// of the position from the point of view of the side to move. + template + Value Evaluation::value() { -template -Value Eval::evaluate(const Position& pos) { + assert(!pos.checkers()); - assert(!pos.checkers()); + // Probe the material hash table + me = Material::probe(pos); - Score mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; - EvalInfo ei; + // If we have a specialized evaluation function for the current material + // configuration, call it and return. + if (me->specialized_eval_exists()) + return me->evaluate(pos); - // Probe the material hash table - ei.me = Material::probe(pos); + // Initialize score by reading the incrementally updated scores included in + // the position object (material + piece square tables) and the material + // imbalance. Score is computed internally from the white point of view. + Score score = pos.psq_score() + me->imbalance() + Eval::Contempt; - // If we have a specialized evaluation function for the current material - // configuration, call it and return. - if (ei.me->specialized_eval_exists()) - return ei.me->evaluate(pos); + // Probe the pawn hash table + pe = Pawns::probe(pos); + score += pe->pawns_score(); - // Initialize score by reading the incrementally updated scores included in - // the position object (material + piece square tables) and the material - // imbalance. Score is computed internally from the white point of view. - Score score = pos.psq_score() + ei.me->imbalance(); + // Early exit if score is high + Value v = (mg_value(score) + eg_value(score)) / 2; + if (abs(v) > LazyThreshold) + return pos.side_to_move() == WHITE ? v : -v; - // Probe the pawn hash table - ei.pi = Pawns::probe(pos); - score += ei.pi->pawns_score(); + // Main evaluation begins here - // Initialize attack and king safety bitboards - ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; - ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.attacks_from(pos.square(BLACK)); - eval_init(pos, ei); - eval_init(pos, ei); + initialize(); + initialize(); - // Pawns blocked or on ranks 2 and 3 will be excluded from the mobility area - Bitboard blockedPawns[] = { - pos.pieces(WHITE, PAWN) & (shift_bb(pos.pieces()) | Rank2BB | Rank3BB), - pos.pieces(BLACK, PAWN) & (shift_bb(pos.pieces()) | Rank7BB | Rank6BB) - }; + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); - // Do not include in mobility area squares protected by enemy pawns, or occupied - // by our blocked pawns or king. - Bitboard mobilityArea[] = { - ~(ei.attackedBy[BLACK][PAWN] | blockedPawns[WHITE] | pos.square(WHITE)), - ~(ei.attackedBy[WHITE][PAWN] | blockedPawns[BLACK] | pos.square(BLACK)) - }; + score += mobility[WHITE] - mobility[BLACK]; - // Evaluate all pieces but king and pawns - score += evaluate_pieces(pos, ei, mobility, mobilityArea); - score += mobility[WHITE] - mobility[BLACK]; + score += evaluate_king() + - evaluate_king(); - // Evaluate kings after all other pieces because we need full attack - // information when computing the king safety evaluation. - score += evaluate_king(pos, ei) - - evaluate_king(pos, ei); + score += evaluate_threats() + - evaluate_threats(); - // Evaluate tactical threats, we need full attack information including king - score += evaluate_threats(pos, ei) - - evaluate_threats(pos, ei); + score += evaluate_passed_pawns() + - evaluate_passed_pawns(); - // Evaluate passed pawns, we need full attack information including king - score += evaluate_passed_pawns(pos, ei) - - evaluate_passed_pawns(pos, ei); + if (pos.non_pawn_material() >= SpaceThreshold) + score += evaluate_space() + - evaluate_space(); - // If both sides have only pawns, score for potential unstoppable pawns - if (!pos.non_pawn_material(WHITE) && !pos.non_pawn_material(BLACK)) - { - Bitboard b; - if ((b = ei.pi->passed_pawns(WHITE)) != 0) - score += Unstoppable * int(relative_rank(WHITE, frontmost_sq(WHITE, b))); + score += evaluate_initiative(eg_value(score)); - if ((b = ei.pi->passed_pawns(BLACK)) != 0) - score -= Unstoppable * int(relative_rank(BLACK, frontmost_sq(BLACK, b))); - } + // Interpolate between a middlegame and a (scaled by 'sf') endgame score + ScaleFactor sf = evaluate_scale_factor(eg_value(score)); + v = mg_value(score) * int(me->game_phase()) + + eg_value(score) * int(PHASE_MIDGAME - me->game_phase()) * sf / SCALE_FACTOR_NORMAL; + + v /= int(PHASE_MIDGAME); + + // In case of tracing add all remaining individual evaluation terms + if (T) + { + Trace::add(MATERIAL, pos.psq_score()); + Trace::add(IMBALANCE, me->imbalance()); + Trace::add(PAWN, pe->pawns_score()); + Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); + if (pos.non_pawn_material() >= SpaceThreshold) + Trace::add(SPACE, evaluate_space() + , evaluate_space()); + Trace::add(TOTAL, score); + } - // 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); - - // 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, eg_value(score)); - - // Interpolate between a middlegame and a (scaled by 'sf') endgame score - Value v = mg_value(score) * int(ei.me->game_phase()) - + eg_value(score) * int(PHASE_MIDGAME - ei.me->game_phase()) * sf / SCALE_FACTOR_NORMAL; - - v /= int(PHASE_MIDGAME); - - // In case of tracing add all remaining individual evaluation terms - if (DoTrace) - { - Trace::add(MATERIAL, pos.psq_score()); - Trace::add(IMBALANCE, ei.me->imbalance()); - Trace::add(PAWN, ei.pi->pawns_score()); - Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); - Trace::add(SPACE, evaluate_space(pos, ei) - , evaluate_space(pos, ei)); - Trace::add(TOTAL, score); + return pos.side_to_move() == WHITE ? v : -v; // Side to move point of view } - return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; // Side to move point of view -} +} // namespace -// Explicit template instantiations -template Value Eval::evaluate(const Position&); -template Value Eval::evaluate(const Position&); +Score Eval::Contempt = SCORE_ZERO; +/// evaluate() is the evaluator for the outer world. It returns a static evaluation +/// of the position from the point of view of the side to move. + +Value Eval::evaluate(const Position& pos) +{ + return Evaluation<>(pos).value() + Eval::Tempo; +} /// trace() is like evaluate(), but instead of returning a value, it returns /// a string (suitable for outputting to stdout) that contains the detailed @@ -887,7 +910,7 @@ std::string Eval::trace(const Position& pos) { std::memset(scores, 0, sizeof(scores)); - Value v = evaluate(pos); + Value v = Evaluation(pos).value() + Eval::Tempo; v = pos.side_to_move() == WHITE ? v : -v; // White's point of view std::stringstream ss; @@ -899,7 +922,7 @@ std::string Eval::trace(const Position& pos) { << " Imbalance | " << Term(IMBALANCE) << " Pawns | " << Term(PAWN) << " Knights | " << Term(KNIGHT) - << " Bishop | " << Term(BISHOP) + << " Bishops | " << Term(BISHOP) << " Rooks | " << Term(ROOK) << " Queens | " << Term(QUEEN) << " Mobility | " << Term(MOBILITY) @@ -907,6 +930,7 @@ std::string Eval::trace(const Position& pos) { << " Threats | " << Term(THREAT) << " Passed pawns | " << Term(PASSED) << " Space | " << Term(SPACE) + << " Initiative | " << Term(INITIATIVE) << "----------------+-------------+-------------+-------------\n" << " Total | " << Term(TOTAL);