X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=daf0c1d74d7b2c1e1b5460b5714852ce94ec9e08;hp=8cb0d11cd324a35d138199e5a4d7d42bb81907cb;hb=4a0db9ea3c34d7663a039c40ce810ba9cb743cca;hpb=002bf4d8dbf804ce8303e01733341a0922af2e71 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 8cb0d11c..daf0c1d7 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 @@ -28,122 +28,82 @@ #include "evaluate.h" #include "material.h" #include "pawns.h" +#include "thread.h" -namespace { - - 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 - }; - - double scores[TERM_NB][COLOR_NB][PHASE_NB]; +namespace Trace { - double to_cp(Value v) { return double(v) / PawnValueEg; } + enum Tracing { NO_TRACE, TRACE }; - void add(int idx, Color c, Score s) { - scores[idx][c][MG] = to_cp(mg_value(s)); - scores[idx][c][EG] = to_cp(eg_value(s)); - } + enum Term { // The first 8 entries are reserved for PieceType + MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, INITIATIVE, TOTAL, TERM_NB + }; - void add(int idx, Score w, Score b = SCORE_ZERO) { - add(idx, WHITE, w); add(idx, BLACK, b); - } + Score scores[TERM_NB][COLOR_NB]; - std::ostream& operator<<(std::ostream& os, Term t) { + double to_cp(Value v) { return double(v) / PawnValueEg; } - if (t == MATERIAL || t == IMBALANCE || t == Term(PAWN) || t == TOTAL) - os << " --- --- | --- --- | "; - else - os << std::setw(5) << scores[t][WHITE][MG] << " " - << std::setw(5) << scores[t][WHITE][EG] << " | " - << std::setw(5) << scores[t][BLACK][MG] << " " - << std::setw(5) << scores[t][BLACK][EG] << " | "; + void add(int idx, Color c, Score s) { + scores[idx][c] = s; + } - os << std::setw(5) << scores[t][WHITE][MG] - scores[t][BLACK][MG] << " " - << std::setw(5) << scores[t][WHITE][EG] - scores[t][BLACK][EG] << " \n"; + void add(int idx, Score w, Score b = SCORE_ZERO) { + scores[idx][WHITE] = w; + scores[idx][BLACK] = b; + } - return os; - } + std::ostream& operator<<(std::ostream& os, Score s) { + os << std::setw(5) << to_cp(mg_value(s)) << " " + << std::setw(5) << to_cp(eg_value(s)); + return os; } - using namespace Trace; + std::ostream& operator<<(std::ostream& os, Term t) { - // Evaluation class contains various information computed and collected - // by the evaluation functions. - template - class Evaluation { + if (t == MATERIAL || t == IMBALANCE || t == INITIATIVE || t == TOTAL) + os << " ---- ----" << " | " << " ---- ----"; + else + os << scores[t][WHITE] << " | " << scores[t][BLACK]; - public: - Evaluation() = delete; - Evaluation(const Position& p) : pos(p) {} - Evaluation& operator=(const Evaluation&) = delete; + os << " | " << scores[t][WHITE] - scores[t][BLACK] << "\n"; + return os; + } +} - Value value(); +using namespace Trace; - 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). - Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB]; +namespace { - // attackedBy2[color] are the squares attacked by 2 pieces of a given color, - // possibly via x-ray or by one pawn and one piece. Diagonal x-ray through - // pawn or squares attacked by 2 pawns are not explicitly added. - Bitboard attackedBy2[COLOR_NB]; + constexpr Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; + constexpr Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; + constexpr Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; + constexpr Bitboard Center = (FileDBB | FileEBB) & (Rank4BB | Rank5BB); - // 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 (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. - Bitboard kingRing[COLOR_NB]; + constexpr Bitboard KingFlank[FILE_NB] = { + QueenSide ^ FileDBB, QueenSide, QueenSide, + CenterFiles, CenterFiles, + KingSide, KingSide, KingSide ^ FileEBB + }; - // kingAttackersCount[color] is the number of pieces of the given color - // which attack a square in the kingRing of the enemy king. - int kingAttackersCount[COLOR_NB]; + // Threshold for lazy and space evaluation + constexpr Value LazyThreshold = Value(1500); + constexpr Value SpaceThreshold = Value(12222); - // 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. - int kingAttackersWeight[COLOR_NB]; + // KingAttackWeights[PieceType] contains king attack weights by piece type + constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 77, 55, 44, 10 }; - // kingAdjacentZoneAttacksCount[color] is the number of attacks by the given - // color to squares directly adjacent to the enemy king. Pieces which attack - // more than one square are counted multiple times. For instance, if there is - // a white knight on g5 and black's king is on g8, this white knight adds 2 - // to kingAdjacentZoneAttacksCount[WHITE]. - int kingAdjacentZoneAttacksCount[COLOR_NB]; - }; + // Penalties for enemy's safe checks + constexpr int QueenSafeCheck = 780; + constexpr int RookSafeCheck = 880; + constexpr int BishopSafeCheck = 435; + constexpr int KnightSafeCheck = 790; - #define V(v) Value(v) - #define S(mg, eg) make_score(mg, eg) +#define S(mg, eg) make_score(mg, eg) // 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(-57,-54), S( -9,-28), S( -2,-10), S( 6, 5), S( 14, 12), // Knights - S( 22, 26), S( 29, 29), S( 36, 29) }, + constexpr Score MobilityBonus[][32] = { + { S(-62,-81), S(-53,-56), S(-12,-30), S( -4,-14), S( 3, 8), S( 13, 15), // Knights + S( 22, 23), S( 28, 27), S( 33, 33) }, { 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) }, @@ -158,132 +118,178 @@ namespace { }; // 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(22, 6), S(33, 9) }, // Knight - { S( 9, 2), S(14, 4) } // Bishop + // pieces if they occupy or can reach an outpost square, bigger if that + // square is supported by a pawn. + constexpr Score Outpost[][2] = { + { 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[] = { S(20, 7), S(45, 20) }; + // RookOnFile[semiopen/open] contains bonuses for each rook when there is + // no (friendly) pawn on the rook file. + constexpr 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) + constexpr Score ThreatByMinor[PIECE_TYPE_NB] = { + S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(62, 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) + constexpr Score ThreatByRook[PIECE_TYPE_NB] = { + S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(51, 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) }; - - // 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) } + // PassedRank[Rank] contains a bonus according to the rank of a passed pawn + constexpr Score PassedRank[RANK_NB] = { + S(0, 0), S(5, 18), S(12, 23), S(10, 31), S(57, 62), S(163, 167), S(271, 250) }; // 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) + constexpr Score PassedFile[FILE_NB] = { + S( -1, 7), S( 0, 9), S(-9, -8), S(-30,-14), + S(-30,-14), S(-9, -8), S( 0, 9), S( -1, 7) }; - // 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); - const Score TrappedBishopA1H1 = S( 50, 50); - - #undef S - #undef V + // PassedDanger[Rank] contains a term to weight the passed score + constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 3, 7, 11, 20 }; + + // Assorted bonuses and penalties + constexpr Score BishopPawns = S( 3, 7); + constexpr Score CloseEnemies = S( 6, 0); + constexpr Score CorneredBishop = S( 50, 50); + constexpr Score Hanging = S( 57, 32); + constexpr Score KingProtector = S( 6, 6); + constexpr Score KnightOnQueen = S( 21, 11); + constexpr Score LongDiagonalBishop = S( 46, 0); + constexpr Score MinorBehindPawn = S( 16, 0); + constexpr Score Overload = S( 13, 6); + constexpr Score PawnlessFlank = S( 19, 84); + constexpr Score RookOnPawn = S( 10, 30); + constexpr Score SliderOnQueen = S( 42, 21); + constexpr Score ThreatByKing = S( 22, 78); + constexpr Score ThreatByPawnPush = S( 45, 40); + constexpr Score ThreatByRank = S( 16, 3); + constexpr Score ThreatBySafePawn = S(173,102); + constexpr Score TrappedRook = S( 92, 0); + constexpr Score WeakQueen = S( 50, 10); + constexpr Score WeakUnopposedPawn = S( 15, 19); + +#undef S + + // Evaluation class computes and stores attacks tables and other working data + template + class Evaluation { - // KingAttackWeights[PieceType] contains king attack weights by piece type - const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 }; + public: + Evaluation() = delete; + explicit Evaluation(const Position& p) : pos(p) {} + Evaluation& operator=(const Evaluation&) = delete; + Value value(); - // Penalties for enemy's safe checks - const int QueenCheck = 780; - const int RookCheck = 880; - const int BishopCheck = 435; - const int KnightCheck = 790; + private: + template void initialize(); + template Score pieces(); + template Score king() const; + template Score threats() const; + template Score passed() const; + template Score space() const; + ScaleFactor scale_factor(Value eg) const; + Score initiative(Value eg) const; - // Threshold for lazy and space evaluation - const Value LazyThreshold = Value(1500); - const Value SpaceThreshold = Value(12222); + 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. Special "piece types" which + // is also calculated is ALL_PIECES. + Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB]; + + // attackedBy2[color] are the squares attacked by 2 pieces of a given color, + // possibly via x-ray or by one pawn and one piece. Diagonal x-ray through + // pawn or squares attacked by 2 pawns are not explicitly added. + Bitboard attackedBy2[COLOR_NB]; + // kingRing[color] are the squares adjacent to the king, plus (only for a + // king on its first rank) the squares two ranks in front. For instance, + // if black's king is on g8, kingRing[BLACK] is f8, h8, f7, g7, h7, f6, g6 + // and h6. It is set to 0 when king safety evaluation is skipped. + Bitboard kingRing[COLOR_NB]; + + // kingAttackersCount[color] is the number of pieces of the given color + // which attack a square in the kingRing of the enemy king. + int kingAttackersCount[COLOR_NB]; + + // 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. + int kingAttackersWeight[COLOR_NB]; + + // kingAttacksCount[color] is the number of attacks by the given color to + // squares directly adjacent to the enemy king. Pieces which attack more + // than one square are counted multiple times. For instance, if there is + // a white knight on g5 and black's king is on g8, this white knight adds 2 + // to kingAttacksCount[WHITE]. + int kingAttacksCount[COLOR_NB]; + }; - // initialize() computes king and pawn attacks, and the king ring bitboard - // for a given color. This is done at the beginning of the evaluation. + // 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 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 Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); + constexpr Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB: Rank7BB | Rank6BB); - // Find our pawns on the first two ranks, and those which are blocked + // Find our pawns that are blocked or on the first two ranks Bitboard b = pos.pieces(Us, PAWN) & (shift(pos.pieces()) | LowRanks); - // Squares occupied by those pawns, by our king, or controlled by enemy pawns + // Squares occupied by those pawns, by our king or queen, or controlled by enemy pawns // are excluded from the mobility area. - mobilityArea[Us] = ~(b | pos.square(Us) | pe->pawn_attacks(Them)); + mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them)); - // Initialise the attack bitboards with the king and pawn information - b = attackedBy[Us][KING] = pos.attacks_from(pos.square(Us)); + // Initialise attackedBy bitboards for kings and pawns + 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]; + attackedBy[Us][ALL_PIECES] = attackedBy[Us][KING] | attackedBy[Us][PAWN]; + attackedBy2[Us] = attackedBy[Us][KING] & attackedBy[Us][PAWN]; // Init our king safety tables only if we are going to use them if (pos.non_pawn_material(Them) >= RookValueMg + KnightValueMg) { - kingRing[Us] = b; + kingRing[Us] = attackedBy[Us][KING]; if (relative_rank(Us, pos.square(Us)) == RANK_1) - kingRing[Us] |= shift(b); + kingRing[Us] |= shift(kingRing[Us]); + + if (file_of(pos.square(Us)) == FILE_H) + kingRing[Us] |= shift(kingRing[Us]); + + else if (file_of(pos.square(Us)) == FILE_A) + kingRing[Us] |= shift(kingRing[Us]); - kingAttackersCount[Them] = popcount(b & pe->pawn_attacks(Them)); - kingAdjacentZoneAttacksCount[Them] = kingAttackersWeight[Them] = 0; + kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them)); + kingAttacksCount[Them] = kingAttackersWeight[Them] = 0; } else kingRing[Us] = kingAttackersCount[Them] = 0; } - // evaluate_pieces() assigns bonuses and penalties to the pieces of a given - // color and type. + // Evaluation::pieces() scores pieces of a given color and type + template template + Score Evaluation::pieces() { - template template - Score Evaluation::evaluate_pieces() { - - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB - : Rank5BB | Rank4BB | Rank3BB); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); + constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB + : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); Bitboard b, bb; @@ -295,51 +301,58 @@ namespace { 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) + if (pos.blockers_for_king(Us) & s) b &= LineBB[pos.square(Us)][s]; attackedBy2[Us] |= attackedBy[Us][ALL_PIECES] & b; - attackedBy[Us][ALL_PIECES] |= attackedBy[Us][Pt] |= b; + attackedBy[Us][Pt] |= b; + attackedBy[Us][ALL_PIECES] |= b; if (b & kingRing[Them]) { kingAttackersCount[Us]++; kingAttackersWeight[Us] += KingAttackWeights[Pt]; - kingAdjacentZoneAttacksCount[Us] += popcount(b & attackedBy[Them][KING]); + kingAttacksCount[Us] += popcount(b & attackedBy[Them][KING]); } int mob = popcount(b & mobilityArea[Us]); 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 + // Bonus if piece is on an outpost square or can reach one bb = OutpostRanks & ~pe->pawn_attacks_span(Them); if (bb & s) - score += Outpost[Pt == BISHOP][!!(attackedBy[Us][PAWN] & s)] * 2; - else - { - bb &= b & ~pos.pieces(Us); - if (bb) - score += Outpost[Pt == BISHOP][!!(attackedBy[Us][PAWN] & bb)]; - } + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & s)] * 2; + + else if (bb &= b & ~pos.pieces(Us)) + score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)]; - // Bonus when behind a pawn - if ( relative_rank(Us, s) < RANK_5 - && (pos.pieces(PAWN) & (s + pawn_push(Us)))) + // Knight and Bishop bonus for being right behind a pawn + if (shift(pos.pieces(PAWN)) & s) score += MinorBehindPawn; - // Penalty for pawns on the same color square as the bishop + // Penalty if the piece is far from the king + score -= KingProtector * distance(s, pos.square(Us)); + if (Pt == BISHOP) - score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s); + { + // Penalty according to number of pawns on the same color square as the + // bishop, bigger when the center files are blocked with pawns. + Bitboard blocked = pos.pieces(Us, PAWN) & shift(pos.pieces()); + + score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s) + * (1 + popcount(blocked & CenterFiles)); + + // Bonus for bishop on a long diagonal which can "see" both center squares + if (more_than_one(attacks_bb(s, pos.pieces(PAWN)) & Center)) + score += LongDiagonalBishop; + } // An important Chess960 pattern: A cornered bishop blocked by a friendly // pawn diagonally in front of it is a very serious problem, especially @@ -348,31 +361,29 @@ 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 - : TrappedBishopA1H1; + score -= !pos.empty(s + d + pawn_push(Us)) ? CorneredBishop * 4 + : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2 + : CorneredBishop; } } if (Pt == ROOK) { - // Bonus for aligning with enemy pawns on the same rank/file + // Bonus for aligning rook with enemy pawns on the same rank/file if (relative_rank(Us, s) >= RANK_5) score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]); - // Bonus when on an open or semi-open file + // Bonus for rook on an open or semi-open file if (pe->semiopen_file(Us, file_of(s))) - score += RookOnFile[!!pe->semiopen_file(Them, 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) { - Square ksq = pos.square(Us); - - if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) - && !pe->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + File kf = file_of(pos.square(Us)); + if ((kf < FILE_E) == (file_of(s) < kf)) score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); } } @@ -380,12 +391,11 @@ namespace { if (Pt == QUEEN) { // Penalty if any relative pin or discovered attack against the queen - Bitboard pinners; - if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s, pinners)) + Bitboard queenPinners; + if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s, queenPinners)) score -= WeakQueen; } } - if (T) Trace::add(Pt, Us, score); @@ -393,126 +403,101 @@ namespace { } - // 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 template - Score Evaluation::evaluate_king() { + // Evaluation::king() assigns bonuses and penalties to a king of a given color + template template + Score Evaluation::king() const { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? NORTH : SOUTH); - const Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB - : AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB + : AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB); const Square ksq = pos.square(Us); - Bitboard kingOnlyDefended, undefended, b, b1, b2, safe, other; - int kingDanger; + Bitboard kingFlank, weak, b, b1, b2, safe, unsafeChecks; // King shelter and enemy pawns storm Score score = pe->king_safety(pos, ksq); + // Find the squares that opponent attacks in our king flank, and the squares + // which are attacked twice in that flank but not defended by our pawns. + kingFlank = KingFlank[file_of(ksq)]; + b1 = attackedBy[Them][ALL_PIECES] & kingFlank & Camp; + b2 = b1 & attackedBy2[Them] & ~attackedBy[Us][PAWN]; + + int tropism = popcount(b1) + popcount(b2); + // Main king safety evaluation - if (kingAttackersCount[Them] > (1 - pos.count(Them))) + if (kingAttackersCount[Them] > 1 - pos.count(Them)) { - // Find the attacked squares which are defended only by our king... - kingOnlyDefended = attackedBy[Them][ALL_PIECES] - & attackedBy[Us][KING] - & ~attackedBy2[Us]; - - // ... and those which are not defended at all in the larger king ring - undefended = attackedBy[Them][ALL_PIECES] - & ~attackedBy[Us][ALL_PIECES] - & 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 weak squares around our king, the absence of queen and - // the quality of the pawn shelter (current 'score' value). - kingDanger = kingAttackersCount[Them] * kingAttackersWeight[Them] - + 102 * kingAdjacentZoneAttacksCount[Them] - + 201 * popcount(kingOnlyDefended) - + 143 * (popcount(undefended) + !!pos.pinned_pieces(Us)) - - 848 * !pos.count(Them) - - 9 * mg_value(score) / 8 - + 40; + int kingDanger = 0; + unsafeChecks = 0; + + // Attacked squares defended at most once by our queen or king + weak = attackedBy[Them][ALL_PIECES] + & ~attackedBy2[Us] + & (~attackedBy[Us][ALL_PIECES] | attackedBy[Us][KING] | attackedBy[Us][QUEEN]); // Analyse the safe enemy's checks which are possible on next move safe = ~pos.pieces(Them); - safe &= ~attackedBy[Us][ALL_PIECES] | (kingOnlyDefended & attackedBy2[Them]); + safe &= ~attackedBy[Us][ALL_PIECES] | (weak & attackedBy2[Them]); - b1 = pos.attacks_from< ROOK>(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) & 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 |= attackedBy2[Them] - & ~(attackedBy2[Us] | pos.pieces(Them)) - & 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 = ~( attackedBy[Us][PAWN] - | (pos.pieces(Them, PAWN) & shift(pos.pieces(PAWN)))); + if ((b1 | b2) & attackedBy[Them][QUEEN] & safe & ~attackedBy[Us][QUEEN]) + kingDanger += QueenSafeCheck; - // Enemy rooks safe and other checks - if (b1 & attackedBy[Them][ROOK] & safe) - kingDanger += RookCheck; + b1 &= attackedBy[Them][ROOK]; + b2 &= attackedBy[Them][BISHOP]; - else if (b1 & attackedBy[Them][ROOK] & other) - score -= OtherCheck; + // Enemy rooks checks + if (b1 & safe) + kingDanger += RookSafeCheck; + else + unsafeChecks |= b1; - // Enemy bishops safe and other checks - if (b2 & attackedBy[Them][BISHOP] & safe) - kingDanger += BishopCheck; + // Enemy bishops checks + if (b2 & safe) + kingDanger += BishopSafeCheck; + else + unsafeChecks |= b2; - else if (b2 & attackedBy[Them][BISHOP] & other) - score -= OtherCheck; - - // Enemy knights safe and other checks + // 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] + + 69 * kingAttacksCount[Them] + + 185 * popcount(kingRing[Us] & weak) + + 150 * popcount(pos.blockers_for_king(Us) | unsafeChecks) + + 4 * tropism + - 873 * !pos.count(Them) + - 6 * mg_value(score) / 8 + - 30; + + // Transform the kingDanger units into a Score, and subtract it from the evaluation if (kingDanger > 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 = 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)); - - // 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 & attackedBy2[Them] & ~attackedBy[Us][PAWN]); - - score -= CloseEnemies * popcount(b); - // Penalty when our king is on a pawnless flank - if (!(pos.pieces(PAWN) & KingFlank[kf])) + if (!(pos.pieces(PAWN) & kingFlank)) score -= PawnlessFlank; + // King tropism bonus, to anticipate slow motion attacks on our king + score -= CloseEnemies * tropism; + if (T) Trace::add(KING, Us, score); @@ -520,52 +505,36 @@ namespace { } - // evaluate_threats() assigns bonuses according to the types of the attacking - // and the attacked pieces. - - template template - Score Evaluation::evaluate_threats() { + // Evaluation::threats() assigns bonuses according to the types of the + // attacking and the attacked pieces. + template template + Score Evaluation::threats() const { - 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 TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); - Bitboard b, weak, defended, stronglyProtected, safeThreats; + Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe; Score score = SCORE_ZERO; - // Non-pawn enemies attacked by a pawn - weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & attackedBy[Us][PAWN]; - - if (weak) - { - b = pos.pieces(Us, PAWN) & ( ~attackedBy[Them][ALL_PIECES] - | attackedBy[Us][ALL_PIECES]); - - safeThreats = (shift(b) | shift(b)) & weak; + // Non-pawn enemies + nonPawnEnemies = pos.pieces(Them) ^ pos.pieces(Them, PAWN); - 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. + // Squares strongly protected by the enemy, either because they defend the + // square with a pawn, or because they defend 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; + defended = nonPawnEnemies & stronglyProtected; // Enemies not strongly protected and under our attack - weak = pos.pieces(Them) - & ~stronglyProtected - & attackedBy[Us][ALL_PIECES]; + weak = pos.pieces(Them) & ~stronglyProtected & attackedBy[Us][ALL_PIECES]; - // Add a bonus according to the kind of attacking pieces + // Safe or protected squares + safe = ~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]; + + // Bonus according to the kind of attacking pieces if (defended | weak) { b = (defended | weak) & (attackedBy[Us][KNIGHT] | attackedBy[Us][BISHOP]); @@ -577,7 +546,7 @@ namespace { score += ThreatByRank * (int)relative_rank(Them, s); } - b = (pos.pieces(Them, QUEEN) | weak) & attackedBy[Us][ROOK]; + b = weak & attackedBy[Us][ROOK]; while (b) { Square s = pop_lsb(&b); @@ -586,43 +555,70 @@ namespace { score += ThreatByRank * (int)relative_rank(Them, s); } + if (weak & attackedBy[Us][KING]) + score += ThreatByKing; + score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]); - b = weak & attackedBy[Us][KING]; - if (b) - score += ThreatByKing[more_than_one(b)]; + b = weak & nonPawnEnemies & attackedBy[Them][ALL_PIECES]; + score += Overload * popcount(b); } + // Bonus for enemy 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(); - // 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) - & ~attackedBy[Us][PAWN]; + // Keep only the squares which are relatively safe + b &= ~attackedBy[Them][PAWN] & safe; + // Bonus for safe pawn threats on the next move + b = pawn_attacks_bb(b) & pos.pieces(Them); score += ThreatByPawnPush * popcount(b); + // Our safe or protected pawns + b = pos.pieces(Us, PAWN) & safe; + + b = pawn_attacks_bb(b) & nonPawnEnemies; + score += ThreatBySafePawn * popcount(b); + + // Bonus for threats on the next moves against enemy queen + if (pos.count(Them) == 1) + { + Square s = pos.square(Them); + safe = mobilityArea[Us] & ~stronglyProtected; + + b = attackedBy[Us][KNIGHT] & pos.attacks_from(s); + + score += KnightOnQueen * popcount(b & safe); + + b = (attackedBy[Us][BISHOP] & pos.attacks_from(s)) + | (attackedBy[Us][ROOK ] & pos.attacks_from(s)); + + score += SliderOnQueen * popcount(b & safe & attackedBy2[Us]); + } + if (T) Trace::add(THREAT, Us, score); return score; } - - // evaluate_passed_pawns() evaluates the passed pawns and candidate passed + // Evaluation::passed() evaluates the passed pawns and candidate passed // pawns of the given color. - template template - Score Evaluation::evaluate_passed_pawns() { + template template + Score Evaluation::passed() const { - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + + auto king_proximity = [&](Color c, Square s) { + return std::min(distance(pos.square(c), s), 5); + }; Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares; Score score = SCORE_ZERO; @@ -635,25 +631,22 @@ namespace { 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); + int w = PassedDanger[r]; - int r = relative_rank(Us, s) - RANK_2; - int rr = r * (r - 1); + Score bonus = PassedRank[r]; - Value mbonus = Passed[MG][r], ebonus = Passed[EG][r]; - - if (rr) + if (w) { 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; + bonus += make_score(0, ( king_proximity(Them, blockSq) * 5 + - king_proximity(Us, blockSq) * 2) * w); // 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 + Up) * rr; + if (r != RANK_7) + bonus -= make_score(0, king_proximity(Us, blockSq + Up) * w); // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -673,7 +666,7 @@ namespace { // 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. @@ -683,18 +676,17 @@ namespace { else if (defendedSquares & blockSq) k += 4; - mbonus += k * rr, ebonus += k * rr; + bonus += make_score(k * w, k * w); } - else if (pos.pieces(Us) & blockSq) - mbonus += rr + r * 2, ebonus += rr + r * 2; - } // rr != 0 + } // w != 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; + // 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))) + bonus = bonus / 2; - score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; + score += bonus + PassedFile[file_of(s)]; } if (T) @@ -704,107 +696,106 @@ namespace { } - // evaluate_space() computes the space evaluation for a given side. The + // Evaluation::space() computes the space evaluation for a given side. The // space evaluation is a simple bonus based on the number of safe squares // available for minor pieces on the central four files on ranks 2--4. Safe // 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 template - Score Evaluation::evaluate_space() { + template template + Score Evaluation::space() const { + + if (pos.non_pawn_material() < SpaceThreshold) + return SCORE_ZERO; - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Bitboard SpaceMask = + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Bitboard SpaceMask = 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. + // Find the available squares for our pieces inside the area defined by SpaceMask Bitboard safe = SpaceMask & ~pos.pieces(Us, PAWN) - & ~attackedBy[Them][PAWN] - & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]); + & ~attackedBy[Them][PAWN]; // Find all squares which are at most three squares behind some friendly pawn Bitboard behind = pos.pieces(Us, PAWN); behind |= (Us == WHITE ? behind >> 8 : behind << 8); behind |= (Us == WHITE ? behind >> 16 : behind << 16); - // 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. - int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); + int bonus = popcount(safe) + popcount(behind & safe); int weight = pos.count(Us) - 2 * pe->open_files(); - return make_score(bonus * weight * weight / 16, 0); + Score score = make_score(bonus * weight * weight / 16, 0); + + if (T) + Trace::add(SPACE, Us, score); + + return score; } - // 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. + // Evaluation::initiative() computes the initiative correction value + // for the position. It is a second order bonus/malus based on the + // known attacking/defending status of the players. template - Score Evaluation::evaluate_initiative(Value eg) { + Score Evaluation::initiative(Value eg) const { - 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); + int outflanking = distance(pos.square(WHITE), pos.square(BLACK)) + - distance(pos.square(WHITE), pos.square(BLACK)); + + bool pawnsOnBothFlanks = (pos.pieces(PAWN) & QueenSide) + && (pos.pieces(PAWN) & KingSide); // Compute the initiative bonus for the attacking side - int initiative = 8 * (pe->pawn_asymmetry() + kingDistance - 17) + 12 * pos.count() + 16 * bothFlanks; + int complexity = 8 * pe->pawn_asymmetry() + + 12 * pos.count() + + 12 * outflanking + + 16 * pawnsOnBothFlanks + + 48 * !pos.non_pawn_material() + -118 ; // 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 v = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg)); + int v = ((eg > 0) - (eg < 0)) * std::max(complexity, -abs(eg)); + + 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 + // Evaluation::scale_factor() computes the scale factor for the winning side template - ScaleFactor Evaluation::evaluate_scale_factor(Value eg) { + ScaleFactor Evaluation::scale_factor(Value eg) const { Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK; - ScaleFactor sf = me->scale_factor(pos, strongSide); + int 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 (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN) + // If scale is not already specific, scale down the endgame via general heuristics + if (sf == SCALE_FACTOR_NORMAL) { - 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, it is even more a draw. - if ( pos.non_pawn_material(WHITE) == BishopValueMg - && pos.non_pawn_material(BLACK) == BishopValueMg) - 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. - 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))) - return ScaleFactor(37 + 7 * pos.count(strongSide)); + if ( pos.opposite_bishops() + && pos.non_pawn_material(WHITE) == BishopValueMg + && pos.non_pawn_material(BLACK) == BishopValueMg) + sf = 8 + 4 * pe->pawn_asymmetry(); + else + sf = std::min(40 + (pos.opposite_bishops() ? 2 : 7) * pos.count(strongSide), sf); + } - return sf; + return ScaleFactor(sf); } - // 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. + // Evaluation::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. template Value Evaluation::value() { @@ -822,11 +813,11 @@ namespace { // 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(); + Score score = pos.psq_score() + me->imbalance() + pos.this_thread()->contempt; // Probe the pawn hash table pe = Pawns::probe(pos); - score += pe->pawns_score(); + score += pe->pawn_score(WHITE) - pe->pawn_score(BLACK); // Early exit if score is high Value v = (mg_value(score) + eg_value(score)) / 2; @@ -838,30 +829,23 @@ namespace { initialize(); initialize(); - score += evaluate_pieces() - evaluate_pieces(); - score += evaluate_pieces() - evaluate_pieces(); - score += evaluate_pieces() - evaluate_pieces(); - score += evaluate_pieces() - evaluate_pieces(); + // Pieces should be evaluated first (populate attack tables) + score += pieces() - pieces() + + pieces() - pieces() + + pieces() - pieces() + + pieces() - pieces(); score += mobility[WHITE] - mobility[BLACK]; - score += evaluate_king() - - evaluate_king(); - - score += evaluate_threats() - - evaluate_threats(); + score += king< WHITE>() - king< BLACK>() + + threats() - threats() + + passed< WHITE>() - passed< BLACK>() + + space< WHITE>() - space< BLACK>(); - score += evaluate_passed_pawns() - - evaluate_passed_pawns(); - - if (pos.non_pawn_material() >= SpaceThreshold) - score += evaluate_space() - - evaluate_space(); - - score += evaluate_initiative(eg_value(score)); + score += initiative(eg_value(score)); // Interpolate between a middlegame and a (scaled by 'sf') endgame score - ScaleFactor sf = evaluate_scale_factor(eg_value(score)); + ScaleFactor sf = 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; @@ -872,28 +856,26 @@ namespace { { Trace::add(MATERIAL, pos.psq_score()); Trace::add(IMBALANCE, me->imbalance()); - Trace::add(PAWN, pe->pawns_score()); + Trace::add(PAWN, pe->pawn_score(WHITE), pe->pawn_score(BLACK)); 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) + Eval::Tempo; // Side to move point of view + return (pos.side_to_move() == WHITE ? v : -v) // Side to move point of view + + Eval::Tempo; } } // namespace -/// 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. +/// 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(); +Value Eval::evaluate(const Position& pos) { + return Evaluation(pos).value(); } + /// trace() is like evaluate(), but instead of returning a value, it returns /// a string (suitable for outputting to stdout) that contains the detailed /// descriptions and values of each evaluation term. Useful for debugging. @@ -902,30 +884,34 @@ std::string Eval::trace(const Position& pos) { std::memset(scores, 0, sizeof(scores)); + pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt + Value v = Evaluation(pos).value(); - v = pos.side_to_move() == WHITE ? v : -v; // White's point of view + + v = pos.side_to_move() == WHITE ? v : -v; // Trace scores are from white's point of view std::stringstream ss; ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2) - << " Eval term | White | Black | Total \n" - << " | MG EG | MG EG | MG EG \n" - << "----------------+-------------+-------------+-------------\n" - << " Material | " << Term(MATERIAL) - << " Imbalance | " << Term(IMBALANCE) - << " Pawns | " << Term(PAWN) - << " Knights | " << Term(KNIGHT) - << " Bishops | " << Term(BISHOP) - << " Rooks | " << Term(ROOK) - << " Queens | " << Term(QUEEN) - << " Mobility | " << Term(MOBILITY) - << " King safety | " << Term(KING) - << " Threats | " << Term(THREAT) - << " Passed pawns | " << Term(PASSED) - << " Space | " << Term(SPACE) - << "----------------+-------------+-------------+-------------\n" - << " Total | " << Term(TOTAL); - - ss << "\nTotal Evaluation: " << to_cp(v) << " (white side)\n"; + << " Term | White | Black | Total \n" + << " | MG EG | MG EG | MG EG \n" + << " ------------+-------------+-------------+------------\n" + << " Material | " << Term(MATERIAL) + << " Imbalance | " << Term(IMBALANCE) + << " Initiative | " << Term(INITIATIVE) + << " Pawns | " << Term(PAWN) + << " Knights | " << Term(KNIGHT) + << " Bishops | " << Term(BISHOP) + << " Rooks | " << Term(ROOK) + << " Queens | " << Term(QUEEN) + << " Mobility | " << Term(MOBILITY) + << " King safety | " << Term(KING) + << " Threats | " << Term(THREAT) + << " Passed | " << Term(PASSED) + << " Space | " << Term(SPACE) + << " ------------+-------------+-------------+------------\n" + << " Total | " << Term(TOTAL); + + ss << "\nTotal evaluation: " << to_cp(v) << " (white side)\n"; return ss.str(); }