X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=60eee7a2a03e0f99af502a20ab60a3bf230faf63;hp=e381d6f8e503d432f3f837fcd40611f0b600a5e8;hb=917fe69f84ffcc53783e1ada41833684dc8a2970;hpb=b948b037a52dea37d26a7210f75405be7f43bf58 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index e381d6f8..60eee7a2 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) 2015-2017 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] << " " @@ -69,16 +80,40 @@ 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(); + int king_distance(Color c, Square s); + 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, @@ -88,7 +123,7 @@ 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. @@ -123,9 +158,9 @@ namespace { { 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(-60,-77), S(-26,-20), S(-11, 27), S( -6, 57), S( -3, 69), S( -1, 82), // Rooks - S( 10,109), S( 16,121), S( 24,131), S( 25,143), S( 32,155), S( 32,163), - S( 43,167), S( 48,171), S( 56,173) }, + { 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), @@ -138,8 +173,8 @@ namespace { // supported by a pawn. If the minor piece occupies an outpost square // then score is doubled. const Score Outpost[][2] = { - { S(22, 6), S(33, 9) }, // Knight - { S( 9, 2), S(14, 4) } // Bishop + { 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 @@ -150,22 +185,22 @@ namespace { // 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) + S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(47, 120) }; const Score ThreatByRook[PIECE_TYPE_NB] = { - S(0, 0), S(0, 25), S(40, 62), S(40, 59), S( 0, 34), S(35, 48) + S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(36, 38) }; // ThreatByKing[on one/on many] contains bonuses for king attacks on // pawns or pieces which are not pawn-defended. - const Score ThreatByKing[] = { S(3, 62), S(9, 138) }; + const Score ThreatByKing[] = { S(3, 65), S(9, 145) }; // 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(5), V( 5), V(31), V(73), V(166), V(252) }, - { V(7), V(14), V(38), V(73), V(166), V(252) } + { V(0), V(5), V( 5), V(32), V(70), V(172), V(217) }, + { V(0), V(7), V(13), V(42), V(70), V(170), V(269) } }; // PassedFile[File] contains a bonus according to the file of a passed pawn @@ -174,35 +209,29 @@ namespace { S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; - // Protector[PieceType-2][distance] contains a protecting bonus for our king, - // indexed by piece type and distance between the piece and the king. - const Score Protector[][8] = { - { S(0, 0), S( 7, 9), S( 7, 1), S( 1, 5), S(-10,-4), S( -1,-4), S( -7,-3), S(-16,-10) }, // Knight - { S(0, 0), S(11, 8), S(-7,-1), S(-1,-2), S( -1,-7), S(-11,-3), S( -9,-1), S(-16, -1) }, // Bishop - { S(0, 0), S(10, 0), S(-2, 2), S(-5, 4), S( -6, 2), S(-14,-3), S( -2,-9), S(-12, -7) }, // Rook - { S(0, 0), S( 3,-5), S( 2,-5), S(-4, 0), S( -9,-6), S( -4, 7), S(-13,-7), S(-10, -7) } // Queen - }; + // Rank factor applied on some bonus for passed pawn on rank 4 or beyond + const int RankFactor[RANK_NB] = {0, 0, 0, 2, 7, 12, 19}; + + // 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 WeakQueen = S( 50, 10); - const Score OtherCheck = S( 10, 10); - const Score CloseEnemies = S( 7, 0); - const Score PawnlessFlank = S( 20, 80); - const Score ThreatByHangingPawn = S( 71, 61); - const Score ThreatBySafePawn = S(182,175); - const Score ThreatByRank = S( 16, 3); - const Score Hanging = S( 48, 27); - const Score ThreatByPawnPush = S( 38, 22); - const Score HinderPassedPawn = S( 7, 0); - - // 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(175,168); + const Score ThreatByRank = S( 16, 3); + const Score Hanging = S( 52, 30); + const Score WeakUnopposedPawn = S( 5, 25); + const Score ThreatByPawnPush = S( 47, 26); + const Score ThreatByAttackOnQueen = S( 42, 21); + const Score HinderPassedPawn = S( 8, 1); + const Score TrappedBishopA1H1 = S( 50, 50); #undef S #undef V @@ -211,24 +240,25 @@ namespace { const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 }; // Penalties for enemy's safe checks - const int QueenCheck = 810; - const int RookCheck = 888; - const int BishopCheck = 400; - const int KnightCheck = 790; + 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. - template - void eval_init(const Position& pos, EvalInfo& ei) { + // 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 template + void Evaluation::initialize() { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? NORTH : SOUTH); - const Square Down = (Us == WHITE ? SOUTH : NORTH); + 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); // Find our pawns on the first two ranks, and those which are blocked @@ -236,35 +266,37 @@ namespace { // Squares occupied by those pawns, by our king, or controlled by enemy pawns // are excluded from the mobility area. - ei.mobilityArea[Us] = ~(b | pos.square(Us) | ei.pe->pawn_attacks(Them)); + mobilityArea[Us] = ~(b | pos.square(Us) | pe->pawn_attacks(Them)); // Initialise the attack bitboards with the king and pawn information - b = ei.attackedBy[Us][KING] = pos.attacks_from(pos.square(Us)); - ei.attackedBy[Us][PAWN] = ei.pe->pawn_attacks(Us); + b = attackedBy[Us][KING] = pos.attacks_from(pos.square(Us)); + attackedBy[Us][PAWN] = pe->pawn_attacks(Us); - ei.attackedBy2[Us] = b & ei.attackedBy[Us][PAWN]; - ei.attackedBy[Us][ALL_PIECES] = b | ei.attackedBy[Us][PAWN]; + 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) >= QueenValueMg) + if (pos.non_pawn_material(Them) >= RookValueMg + KnightValueMg) { - ei.kingRing[Us] = b | shift(b); - ei.kingAttackersCount[Them] = popcount(b & ei.pe->pawn_attacks(Them)); - ei.kingAdjacentZoneAttacksCount[Them] = ei.kingAttackersWeight[Them] = 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[Us] = ei.kingAttackersCount[Them] = 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) { + template template + Score Evaluation::evaluate_pieces() { const Color Them = (Us == WHITE ? BLACK : WHITE); - const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); @@ -273,46 +305,52 @@ namespace { Square s; Score score = SCORE_ZERO; - ei.attackedBy[Us][Pt] = 0; + 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 (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 (b & ei.kingRing[Them]) + if (Pt == QUEEN) + attackedBy[Us][QUEEN_DIAGONAL] |= b & PseudoAttacks[BISHOP][s]; + + 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]); } - int mob = popcount(b & ei.mobilityArea[Us]); + int mob = popcount(b & mobilityArea[Us]); - mobility[Us] += MobilityBonus[Pt-2][mob]; + mobility[Us] += MobilityBonus[Pt - 2][mob]; // Bonus for this piece as a king protector - score += Protector[Pt-2][distance(s, pos.square(Us))]; + score += KingProtector[Pt - 2] * distance(s, pos.square(Us)); if (Pt == BISHOP || Pt == KNIGHT) { // Bonus for outpost squares - bb = OutpostRanks & ~ei.pe->pawn_attacks_span(Them); + bb = OutpostRanks & ~pe->pawn_attacks_span(Them); if (bb & s) - score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)] * 2; + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & s)] * 2; else { bb &= b & ~pos.pieces(Us); if (bb) - score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & bb)]; + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)]; } // Bonus when behind a pawn @@ -320,9 +358,15 @@ 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.pe->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 @@ -331,7 +375,7 @@ 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 ? EAST : WEST); + 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 @@ -346,8 +390,8 @@ namespace { score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]); // Bonus when on an open or semi-open file - if (ei.pe->semiopen_file(Us, file_of(s))) - score += RookOnFile[!!ei.pe->semiopen_file(Them, file_of(s))]; + if (pe->semiopen_file(Us, file_of(s))) + score += RookOnFile[bool(pe->semiopen_file(Them, file_of(s)))]; // Penalty when trapped by the king, even more if the king cannot castle else if (mob <= 3) @@ -355,7 +399,7 @@ namespace { Square ksq = pos.square(Us); if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) - && !ei.pe->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)); } } @@ -369,121 +413,95 @@ 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); + return score; } - template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*) { return SCORE_ZERO; } - template<> - Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*) { return SCORE_ZERO; } - // evaluate_king() assigns bonuses and penalties to a king of a given color - 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 - }; - - 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 ? NORTH : SOUTH); - const Bitboard Camp = (Us == WHITE ? ~Bitboard(0) ^ Rank6BB ^ Rank7BB ^ Rank8BB - : ~Bitboard(0) ^ Rank1BB ^ Rank2BB ^ Rank3BB); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB + : AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB); const Square ksq = pos.square(Us); - Bitboard undefended, b, b1, b2, safe, other; - int kingDanger; + Bitboard weak, b, b1, b2, safe, unsafeChecks; // King shelter and enemy pawns storm - Score score = ei.pe->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 our 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 = ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them] - + 103 * ei.kingAdjacentZoneAttacksCount[Them] - + 190 * popcount(undefended) - + 142 * (popcount(b) + !!pos.pinned_pieces(Us)) - - 810 * !pos.count(Them) - - 6 * mg_value(score) / 5 - 5; + // 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]); + + int kingDanger = unsafeChecks = 0; // Analyse the safe enemy's checks which are possible on next move safe = ~pos.pieces(Them); - safe &= ~ei.attackedBy[Us][ALL_PIECES] | (undefended & ei.attackedBy2[Them]); + safe &= ~attackedBy[Us][ALL_PIECES] | (weak & attackedBy2[Them]); - b1 = pos.attacks_from(ksq); - b2 = pos.attacks_from(ksq); + b1 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN)); + b2 = attacks_bb(ksq, pos.pieces() ^ pos.pieces(Us, QUEEN)); // Enemy queen safe checks - if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe) - kingDanger += QueenCheck; - - // For minors and rooks, also consider the square safe if attacked twice, - // and only defended by our queen. - safe |= ei.attackedBy2[Them] - & ~(ei.attackedBy2[Us] | pos.pieces(Them)) - & ei.attackedBy[Us][QUEEN]; - - // Some other potential checks are also analysed, even from squares - // currently occupied by the opponent own pieces, as long as the square - // is not attacked by our pawns, and is not occupied by a blocked pawn. - other = ~( ei.attackedBy[Us][PAWN] - | (pos.pieces(Them, PAWN) & shift(pos.pieces(PAWN)))); - - // Enemy rooks safe and other checks - if (b1 & ei.attackedBy[Them][ROOK] & safe) - kingDanger += RookCheck; - - else if (b1 & ei.attackedBy[Them][ROOK] & other) - score -= OtherCheck; - - // Enemy bishops safe and other checks - if (b2 & ei.attackedBy[Them][BISHOP] & safe) - kingDanger += BishopCheck; - - else if (b2 & ei.attackedBy[Them][BISHOP] & other) - score -= OtherCheck; - - // Enemy knights safe and other checks - b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT]; + 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; - - else if (b & other) - score -= OtherCheck; - - // Transform the kingDanger units into a Score, and substract 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 subtract it from the evaluation if (kingDanger > 0) - score -= make_score(kingDanger * kingDanger / 4096, 0); + { + int mobilityDanger = mg_value(mobility[Them] - mobility[Us]); + kingDanger = std::max(0, kingDanger + mobilityDanger); + score -= make_score(kingDanger * kingDanger / 4096, kingDanger / 16); + } } // King tropism: firstly, find squares that opponent attacks in our king flank File kf = file_of(ksq); - b = ei.attackedBy[Them][ALL_PIECES] & KingFlank[kf] & Camp; + 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)); @@ -491,7 +509,7 @@ 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); @@ -499,7 +517,7 @@ namespace { if (!(pos.pieces(PAWN) & KingFlank[kf])) score -= PawnlessFlank; - if (DoTrace) + if (T) Trace::add(KING, Us, score); return score; @@ -509,39 +527,35 @@ 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) { + template template + Score Evaluation::evaluate_threats() { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? NORTH : SOUTH); - const Square Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); - const Square Right = (Us == WHITE ? NORTH_EAST : SOUTH_WEST); - const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); - const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + 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, stronglyProtected, safeThreats; Score score = SCORE_ZERO; // 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]); + b = pos.pieces(Us, PAWN) & ( ~attackedBy[Them][ALL_PIECES] + | attackedBy[Us][ALL_PIECES]); safeThreats = (shift(b) | shift(b)) & weak; score += ThreatBySafePawn * popcount(safeThreats); - - if (weak ^ safeThreats) - score += ThreatByHangingPawn; } // 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 = ei.attackedBy[Them][PAWN] - | (ei.attackedBy2[Them] & ~ei.attackedBy2[Us]); + stronglyProtected = attackedBy[Them][PAWN] + | (attackedBy2[Them] & ~attackedBy2[Us]); // Non-pawn enemies, strongly protected defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) @@ -550,12 +564,12 @@ namespace { // Enemies not strongly protected and under our attack weak = pos.pieces(Them) & ~stronglyProtected - & ei.attackedBy[Us][ALL_PIECES]; + & 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) { Square s = pop_lsb(&b); @@ -564,7 +578,7 @@ namespace { 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) { Square s = pop_lsb(&b); @@ -573,72 +587,90 @@ namespace { 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(b | (shift(b & TRank2BB) & ~pos.pieces())); + // Bonus for opponent unopposed weak pawns + if (pos.pieces(Us, ROOK, QUEEN)) + score += WeakUnopposedPawn * pe->weak_unopposed(Them); - b &= ~pos.pieces() - & ~ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); + // 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(); + // Keep only the squares which are not completely unsafe + b &= ~attackedBy[Them][PAWN] + & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]); + + // 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; } + // king_distance() returns an estimate of the distance that the king + // of the given color has to run to reach square s. + template + int Evaluation::king_distance(Color c, Square s) { + return std::min(distance(pos.square(c), s), 5); + } - // evaluate_passer_pawns() evaluates the passed pawns and candidate passed + // evaluate_passed_pawns() evaluates the passed pawns and candidate passed // pawns of the given color. - template - Score evaluate_passer_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, bb, squaresToQueen, defendedSquares, unsafeSquares; Score score = SCORE_ZERO; - b = ei.pe->passed_pawns(Us); + b = pe->passed_pawns(Us); while (b) { Square s = pop_lsb(&b); - assert(!(pos.pieces(PAWN) & forward_bb(Us, s))); + assert(!(pos.pieces(Them, PAWN) & forward_file_bb(Us, s + Up))); - bb = forward_bb(Us, s) & (ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them)); + 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); + int r = relative_rank(Us, s); + int rr = RankFactor[r]; Value mbonus = Passed[MG][r], ebonus = Passed[EG][r]; 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; + ebonus += (king_distance(Them, blockSq) * 5 - king_distance(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; + if (r != RANK_7) + ebonus -= king_distance(Us, blockSq + Up) * rr; // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -646,19 +678,19 @@ 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); - 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. - int k = !unsafeSquares ? 18 : !(unsafeSquares & blockSq) ? 8 : 0; + int k = !unsafeSquares ? 20 : !(unsafeSquares & blockSq) ? 9 : 0; // If the path to the queen is fully defended, assign a big bonus. // Otherwise assign a smaller bonus if the block square is defended. @@ -675,14 +707,14 @@ namespace { } // rr != 0 // Scale down bonus for candidate passers which need more than one - // pawn push to become passed. - if (!pos.pawn_passed(Us, s + pawn_push(Us))) + // 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); return score; @@ -695,8 +727,9 @@ 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 = @@ -708,8 +741,8 @@ namespace { // 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); @@ -721,7 +754,7 @@ namespace { // ...count safe + (behind & safe) with a single popcount. int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); - int weight = pos.count(Us) - 2 * ei.pe->open_files(); + int weight = pos.count(Us) - 2 * pe->open_files(); return make_score(bonus * weight * weight / 16, 0); } @@ -730,29 +763,36 @@ namespace { // 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)); bool bothFlanks = (pos.pieces(PAWN) & QueenSide) && (pos.pieces(PAWN) & KingSide); // Compute the initiative bonus for the attacking side - int initiative = 8 * (asymmetry + kingDistance - 17) + 12 * pos.count() + 16 * bothFlanks; + 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 change sign after the bonus. - int value = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg)); + int v = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg)); - return make_score(0, value); + if (T) + Trace::add(INITIATIVE, make_score(0, v)); + + 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. @@ -781,101 +821,99 @@ namespace { 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() { + + assert(!pos.checkers()); + + // Probe the material hash table + me = Material::probe(pos); + + // 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); + + // 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; + + // Probe the pawn hash table + pe = Pawns::probe(pos); + score += pe->pawns_score(); + + // 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; -template -Value Eval::evaluate(const Position& pos) { - - assert(!pos.checkers()); - - Score mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; - Value v; - EvalInfo ei; - - // Probe the material hash table - ei.me = Material::probe(pos); - - // 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); - - // 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(); - - // Probe the pawn hash table - ei.pe = Pawns::probe(pos); - score += ei.pe->pawns_score(); - - // Early exit if score is high - v = (mg_value(score) + eg_value(score)) / 2; - if (abs(v) > LazyThreshold) - return pos.side_to_move() == WHITE ? v : -v; - - // Initialize attack and king safety bitboards - eval_init(pos, ei); - eval_init(pos, ei); - - // Evaluate all pieces but king and pawns - score += evaluate_pieces(pos, ei, mobility); - score += mobility[WHITE] - mobility[BLACK]; - - // 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); - - // Evaluate tactical threats, we need full attack information including king - score += evaluate_threats(pos, ei) - - evaluate_threats(pos, ei); - - // Evaluate passed pawns, we need full attack information including king - score += evaluate_passer_pawns(pos, ei) - - evaluate_passer_pawns(pos, ei); - - // Evaluate space for both sides, only during opening - if (pos.non_pawn_material() >= SpaceThreshold) - score += evaluate_space(pos, ei) - - evaluate_space(pos, ei); - - // Evaluate position potential for the winning side - score += evaluate_initiative(pos, ei.pe->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 - 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.pe->pawns_score()); - Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); - if (pos.non_pawn_material() >= SpaceThreshold) - Trace::add(SPACE, evaluate_space(pos, ei) - , evaluate_space(pos, ei)); - Trace::add(TOTAL, score); + // Main evaluation begins here + + initialize(); + initialize(); + + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); + score += evaluate_pieces() - evaluate_pieces(); + + score += mobility[WHITE] - mobility[BLACK]; + + score += evaluate_king() + - evaluate_king(); + + score += evaluate_threats() + - evaluate_threats(); + + score += evaluate_passed_pawns() + - evaluate_passed_pawns(); + + if (pos.non_pawn_material() >= SpaceThreshold) + score += evaluate_space() + - evaluate_space(); + + score += evaluate_initiative(eg_value(score)); + + // 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); + } + + 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 + +Score Eval::Contempt = SCORE_ZERO; -// Explicit template instantiations -template Value Eval::evaluate(const Position&); -template Value Eval::evaluate(const Position&); +/// 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 @@ -885,7 +923,7 @@ 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; @@ -897,7 +935,7 @@ 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) @@ -905,6 +943,7 @@ std::string Eval::trace(const Position& pos) { << " Threats | " << Term(THREAT) << " Passed pawns | " << Term(PASSED) << " Space | " << Term(SPACE) + << " Initiative | " << Term(INITIATIVE) << "----------------+-------------+-------------+-------------\n" << " Total | " << Term(TOTAL);