X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=7c7ce95cebcf27d72960c0d34d45857e3d10f052;hp=a52cdf0928ab5cdc72800eb4439464979cd57110;hb=384bff4264f199ded8fa28d241ce0e7dc021a97c;hpb=82d66f6b72c656a3efc4fd54b6eb489a8f74a945 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index a52cdf09..7c7ce95c 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) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2020 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 @@ -78,7 +78,7 @@ namespace { constexpr Value SpaceThreshold = Value(12222); // KingAttackWeights[PieceType] contains king attack weights by piece type - constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 77, 55, 44, 10 }; + constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 }; // Penalties for enemy's safe checks constexpr int QueenSafeCheck = 780; @@ -108,32 +108,25 @@ namespace { // RookOnFile[semiopen/open] contains bonuses for each rook when there is // no (friendly) pawn on the rook file. - constexpr Score RookOnFile[] = { S(18, 7), S(44, 20) }; + constexpr Score RookOnFile[] = { S(21, 4), S(47, 25) }; // 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. constexpr Score ThreatByMinor[PIECE_TYPE_NB] = { - S(0, 0), S(0, 31), S(39, 42), S(57, 44), S(68, 112), S(62, 120) + S(0, 0), S(6, 32), S(59, 41), S(79, 56), S(90, 119), S(79, 161) }; constexpr Score ThreatByRook[PIECE_TYPE_NB] = { - S(0, 0), S(0, 24), S(38, 71), S(38, 61), S(0, 38), S(51, 38) + S(0, 0), S(3, 44), S(38, 71), S(38, 61), S(0, 38), S(51, 38) }; // 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 - 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) + S(0, 0), S(10, 28), S(17, 33), S(15, 41), S(62, 72), S(168, 177), S(276, 260) }; // Assorted bonuses and penalties - constexpr Score AttacksOnSpaceArea = S( 4, 0); constexpr Score BishopPawns = S( 3, 7); constexpr Score CorneredBishop = S( 50, 50); constexpr Score FlankAttacks = S( 8, 0); @@ -142,16 +135,17 @@ namespace { constexpr Score KnightOnQueen = S( 16, 12); constexpr Score LongDiagonalBishop = S( 45, 0); constexpr Score MinorBehindPawn = S( 18, 3); - constexpr Score Outpost = S( 18, 6); + constexpr Score Outpost = S( 30, 21); + constexpr Score PassedFile = S( 11, 8); constexpr Score PawnlessFlank = S( 17, 95); constexpr Score RestrictedPiece = S( 7, 7); - constexpr Score RookOnPawn = S( 10, 32); + constexpr Score ReachableOutpost = S( 32, 10); + constexpr Score RookOnQueenFile = S( 7, 6); constexpr Score SliderOnQueen = S( 59, 18); constexpr Score ThreatByKing = S( 24, 89); constexpr Score ThreatByPawnPush = S( 48, 39); - constexpr Score ThreatByRank = S( 13, 0); constexpr Score ThreatBySafePawn = S(173, 94); - constexpr Score TrappedRook = S( 47, 4); + constexpr Score TrappedRook = S( 52, 10); constexpr Score WeakQueen = S( 49, 15); #undef S @@ -174,7 +168,7 @@ namespace { template Score passed() const; template Score space() const; ScaleFactor scale_factor(Value eg) const; - Score initiative(Value eg) const; + Score initiative(Score score) const; const Position& pos; Material::Entry* me; @@ -220,8 +214,8 @@ namespace { void Evaluation::initialize() { constexpr Color Them = (Us == WHITE ? BLACK : WHITE); - constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); - constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); + constexpr Direction Up = pawn_push(Us); + constexpr Direction Down = -Up; constexpr Bitboard LowRanks = (Us == WHITE ? Rank2BB | Rank3BB : Rank7BB | Rank6BB); const Square ksq = pos.square(Us); @@ -231,9 +225,9 @@ namespace { // 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 queen or controlled by - // enemy pawns are excluded from the mobility area. - mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them)); + // Squares occupied by those pawns, by our king or queen, by blockers to attacks on our king + // or controlled by enemy pawns are excluded from the mobility area. + mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pos.blockers_for_king(Us) | pe->pawn_attacks(Them)); // Initialize attackedBy[] for king and pawns attackedBy[Us][KING] = pos.attacks_from(ksq); @@ -242,15 +236,9 @@ namespace { attackedBy2[Us] = dblAttackByPawn | (attackedBy[Us][KING] & attackedBy[Us][PAWN]); // Init our king safety tables - kingRing[Us] = attackedBy[Us][KING]; - if (relative_rank(Us, ksq) == RANK_1) - kingRing[Us] |= shift(kingRing[Us]); - - if (file_of(ksq) == FILE_H) - kingRing[Us] |= shift(kingRing[Us]); - - else if (file_of(ksq) == FILE_A) - kingRing[Us] |= shift(kingRing[Us]); + Square s = make_square(clamp(file_of(ksq), FILE_B, FILE_G), + clamp(rank_of(ksq), RANK_2, RANK_7)); + kingRing[Us] = PseudoAttacks[KING][s] | s; kingAttackersCount[Them] = popcount(kingRing[Us] & pe->pawn_attacks(Them)); kingAttacksCount[Them] = kingAttackersWeight[Them] = 0; @@ -265,7 +253,7 @@ namespace { Score Evaluation::pieces() { constexpr Color Them = (Us == WHITE ? BLACK : WHITE); - constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); + constexpr Direction Down = -pawn_push(Us); constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); @@ -305,11 +293,11 @@ namespace { // Bonus if piece is on an outpost square or can reach one bb = OutpostRanks & attackedBy[Us][PAWN] & ~pe->pawn_attacks_span(Them); if (bb & s) - score += Outpost * (Pt == KNIGHT ? 4 : 2); - - else if (bb & b & ~pos.pieces(Us)) score += Outpost * (Pt == KNIGHT ? 2 : 1); + else if (Pt == KNIGHT && bb & b & ~pos.pieces(Us)) + score += ReachableOutpost; + // Knight and Bishop bonus for being right behind a pawn if (shift(pos.pieces(PAWN)) & s) score += MinorBehindPawn; @@ -329,32 +317,31 @@ namespace { // 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 - // when that pawn is also blocked. - if ( Pt == BISHOP - && pos.is_chess960() - && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) - { - 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)) ? CorneredBishop * 4 - : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2 - : CorneredBishop; + // An important Chess960 pattern: a cornered bishop blocked by a friendly + // pawn diagonally in front of it is a very serious problem, especially + // when that pawn is also blocked. + if ( pos.is_chess960() + && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) + { + 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)) ? CorneredBishop * 4 + : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2 + : CorneredBishop; + } } } if (Pt == ROOK) { - // 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 for rook on the same file as a queen + if (file_bb(s) & pos.pieces(QUEEN)) + score += RookOnQueenFile; // Bonus for rook on an open or semi-open file if (pos.is_on_semiopen_file(Us, s)) - score += RookOnFile[bool(pos.is_on_semiopen_file(Them, s))]; + score += RookOnFile[pos.is_on_semiopen_file(Them, s)]; // Penalty when trapped by the king, even more if the king cannot castle else if (mob <= 3) @@ -388,7 +375,7 @@ namespace { constexpr Bitboard Camp = (Us == WHITE ? AllSquares ^ Rank6BB ^ Rank7BB ^ Rank8BB : AllSquares ^ Rank1BB ^ Rank2BB ^ Rank3BB); - Bitboard weak, b1, b2, safe, unsafeChecks = 0; + Bitboard weak, b1, b2, b3, safe, unsafeChecks = 0; Bitboard rookChecks, queenChecks, bishopChecks, knightChecks; int kingDanger = 0; const Square ksq = pos.square(Us); @@ -447,28 +434,27 @@ namespace { else unsafeChecks |= knightChecks; - // Unsafe or occupied checking squares will also be considered, as long as - // the square is in the attacker's mobility area. - unsafeChecks &= mobilityArea[Them]; - - // Find the squares that opponent attacks in our king flank, and the squares - // which are attacked twice in that flank. + // Find the squares that opponent attacks in our king flank, the squares + // which they attack twice in that flank, and the squares that we defend. b1 = attackedBy[Them][ALL_PIECES] & KingFlank[file_of(ksq)] & Camp; b2 = b1 & attackedBy2[Them]; + b3 = attackedBy[Us][ALL_PIECES] & KingFlank[file_of(ksq)] & Camp; - int kingFlankAttacks = popcount(b1) + popcount(b2); + int kingFlankAttack = popcount(b1) + popcount(b2); + int kingFlankDefense = popcount(b3); kingDanger += kingAttackersCount[Them] * kingAttackersWeight[Them] - + 69 * kingAttacksCount[Them] + 185 * popcount(kingRing[Us] & weak) - - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING]) - - 35 * bool(attackedBy[Us][BISHOP] & attackedBy[Us][KING]) - + 150 * popcount(pos.blockers_for_king(Us) | unsafeChecks) + + 148 * popcount(unsafeChecks) + + 98 * popcount(pos.blockers_for_king(Us)) + + 69 * kingAttacksCount[Them] + + 3 * kingFlankAttack * kingFlankAttack / 8 + + mg_value(mobility[Them] - mobility[Us]) - 873 * !pos.count(Them) + - 100 * bool(attackedBy[Us][KNIGHT] & attackedBy[Us][KING]) - 6 * mg_value(score) / 8 - + mg_value(mobility[Them] - mobility[Us]) - + 5 * kingFlankAttacks * kingFlankAttacks / 16 - - 7; + - 4 * kingFlankDefense + + 37; // Transform the kingDanger units into a Score, and subtract it from the evaluation if (kingDanger > 100) @@ -479,7 +465,7 @@ namespace { score -= PawnlessFlank; // Penalty if king flank is under attack, potentially moving toward the king - score -= FlankAttacks * kingFlankAttacks; + score -= FlankAttacks * kingFlankAttack; if (T) Trace::add(KING, Us, score); @@ -494,7 +480,7 @@ namespace { Score Evaluation::threats() const { constexpr Color Them = (Us == WHITE ? BLACK : WHITE); - constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Direction Up = pawn_push(Us); constexpr Bitboard TRank3BB = (Us == WHITE ? Rank3BB : Rank6BB); Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safe; @@ -514,29 +500,16 @@ namespace { // Enemies not strongly protected and under our attack weak = pos.pieces(Them) & ~stronglyProtected & attackedBy[Us][ALL_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]); while (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); - } + score += ThreatByMinor[type_of(pos.piece_on(pop_lsb(&b)))]; b = weak & attackedBy[Us][ROOK]; while (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 += ThreatByRook[type_of(pos.piece_on(pop_lsb(&b)))]; if (weak & attackedBy[Us][KING]) score += ThreatByKing; @@ -553,6 +526,14 @@ namespace { score += RestrictedPiece * popcount(b); + // Protected or unattacked squares + safe = ~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]; + + // Bonus for attacking enemy pieces with our relatively safe pawns + b = pos.pieces(Us, PAWN) & safe; + b = pawn_attacks_bb(b) & nonPawnEnemies; + score += ThreatBySafePawn * popcount(b); + // 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(); @@ -564,12 +545,6 @@ namespace { b = pawn_attacks_bb(b) & nonPawnEnemies; 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) { @@ -599,13 +574,13 @@ namespace { Score Evaluation::passed() const { constexpr Color Them = (Us == WHITE ? BLACK : WHITE); - constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); + constexpr Direction Up = pawn_push(Us); auto king_proximity = [&](Color c, Square s) { return std::min(distance(pos.square(c), s), 5); }; - Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares; + Bitboard b, bb, squaresToQueen, unsafeSquares; Score score = SCORE_ZERO; b = pe->passed_pawns(Us); @@ -622,12 +597,12 @@ namespace { if (r > RANK_3) { - int w = (r-2) * (r-2) + 2; + int w = 5 * r - 13; Square blockSq = s + Up; // Adjust bonus based on the king's proximity - bonus += make_score(0, ( king_proximity(Them, blockSq) * 5 - - king_proximity(Us, blockSq) * 2) * w); + bonus += make_score(0, ( (king_proximity(Them, blockSq) * 19) / 4 + - king_proximity(Us, blockSq) * 2) * w); // If blockSq is not the queening square then consider also a second push if (r != RANK_7) @@ -636,16 +611,13 @@ namespace { // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) { - defendedSquares = squaresToQueen = forward_file_bb(Us, s); + squaresToQueen = forward_file_bb(Us, s); unsafeSquares = passed_pawn_span(Us, s); bb = forward_file_bb(Them, s) & pos.pieces(ROOK, QUEEN); - if (!(pos.pieces(Us) & bb)) - defendedSquares &= attackedBy[Us][ALL_PIECES]; - if (!(pos.pieces(Them) & bb)) - unsafeSquares &= attackedBy[Them][ALL_PIECES] | pos.pieces(Them); + unsafeSquares &= attackedBy[Them][ALL_PIECES]; // If there are no enemy attacks on passed pawn span, assign a big bonus. // Otherwise assign a smaller bonus if the path to queen is not attacked @@ -656,7 +628,7 @@ namespace { 0 ; // Assign a larger bonus if the block square is defended - if (defendedSquares & blockSq) + if ((pos.pieces(Us) & bb) || (attackedBy[Us][ALL_PIECES] & blockSq)) k += 5; bonus += make_score(k * w, k * w); @@ -666,10 +638,10 @@ namespace { // 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))) + || (pos.pieces(PAWN) & (s + Up))) bonus = bonus / 2; - score += bonus + PassedFile[file_of(s)]; + score += bonus - PassedFile * map_to_queenside(file_of(s)); } if (T) @@ -693,7 +665,7 @@ namespace { return SCORE_ZERO; constexpr Color Them = (Us == WHITE ? BLACK : WHITE); - constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); + constexpr Direction Down = -pawn_push(Us); constexpr Bitboard SpaceMask = Us == WHITE ? CenterFiles & (Rank2BB | Rank3BB | Rank4BB) : CenterFiles & (Rank7BB | Rank6BB | Rank5BB); @@ -708,12 +680,10 @@ namespace { behind |= shift(behind); behind |= shift(behind); - int bonus = popcount(safe) + popcount(behind & safe); + int bonus = popcount(safe) + popcount(behind & safe & ~attackedBy[Them][ALL_PIECES]); int weight = pos.count(Us) - 1; Score score = make_score(bonus * weight * weight / 16, 0); - score -= AttacksOnSpaceArea * popcount(attackedBy[Them][ALL_PIECES] & behind & safe); - if (T) Trace::add(SPACE, Us, score); @@ -726,31 +696,44 @@ namespace { // known attacking/defending status of the players. template - Score Evaluation::initiative(Value eg) const { + Score Evaluation::initiative(Score score) const { + + Value mg = mg_value(score); + Value eg = eg_value(score); int outflanking = distance(pos.square(WHITE), pos.square(BLACK)) - distance(pos.square(WHITE), pos.square(BLACK)); + bool infiltration = rank_of(pos.square(WHITE)) > RANK_4 + || rank_of(pos.square(BLACK)) < RANK_5; + bool pawnsOnBothFlanks = (pos.pieces(PAWN) & QueenSide) && (pos.pieces(PAWN) & KingSide); + bool almostUnwinnable = !pe->passed_count() + && outflanking < 0 + && !pawnsOnBothFlanks; + // Compute the initiative bonus for the attacking side int complexity = 9 * pe->passed_count() + 11 * pos.count() + 9 * outflanking - + 18 * pawnsOnBothFlanks - + 49 * !pos.non_pawn_material() - -103 ; - - // 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. + + 12 * infiltration + + 21 * pawnsOnBothFlanks + + 51 * !pos.non_pawn_material() + - 43 * almostUnwinnable + - 100 ; + + // Now apply the bonus: note that we find the attacking side by extracting the + // sign of the midgame or endgame values, and that we carefully cap the bonus + // so that the midgame and endgame scores do not change sign after the bonus. + int u = ((mg > 0) - (mg < 0)) * std::max(std::min(complexity + 50, 0), -abs(mg)); int v = ((eg > 0) - (eg < 0)) * std::max(complexity, -abs(eg)); if (T) - Trace::add(INITIATIVE, make_score(0, v)); + Trace::add(INITIATIVE, make_score(u, v)); - return make_score(0, v); + return make_score(u, v); } @@ -767,10 +750,11 @@ namespace { { if ( pos.opposite_bishops() && pos.non_pawn_material() == 2 * BishopValueMg) - sf = 16 + 4 * pe->passed_count(); + sf = 22 ; else - sf = std::min(40 + (pos.opposite_bishops() ? 2 : 7) * pos.count(strongSide), sf); + sf = std::min(sf, 36 + (pos.opposite_bishops() ? 2 : 7) * pos.count(strongSide)); + sf = std::max(0, sf - (pos.rule50_count() - 12) / 4); } return ScaleFactor(sf); @@ -826,7 +810,7 @@ namespace { + passed< WHITE>() - passed< BLACK>() + space< WHITE>() - space< BLACK>(); - score += initiative(eg_value(score)); + score += initiative(score); // Interpolate between a middlegame and a (scaled by 'sf') endgame score ScaleFactor sf = scale_factor(eg_value(score)); @@ -866,6 +850,9 @@ Value Eval::evaluate(const Position& pos) { std::string Eval::trace(const Position& pos) { + if (pos.checkers()) + return "Total evaluation: none (in check)"; + std::memset(scores, 0, sizeof(scores)); pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt