X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=c581c8e72e90fa7ef4ac64408b1fa56405b1d21b;hp=b8a002428d5a1a6cc4e9024438a792267b0a7d10;hb=8df1cd10df0869f05916d1eb19e33b66127fcb86;hpb=fc0a1f37cf2029af3d35221423da7ac512afbf88 diff --git a/src/pawns.cpp b/src/pawns.cpp index b8a00242..c581c8e7 100644 --- a/src/pawns.cpp +++ b/src/pawns.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) 2015-2018 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad + Copyright (C) 2015-2019 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 @@ -31,43 +31,31 @@ namespace { #define V Value #define S(mg, eg) make_score(mg, eg) - // Isolated pawn penalty - constexpr Score Isolated = S(13, 16); - - // Backward pawn penalty - constexpr Score Backward = S(17, 11); + // Pawn penalties + constexpr Score Backward = S( 9, 24); + constexpr Score Doubled = S(11, 56); + constexpr Score Isolated = S( 5, 15); // Connected pawn bonus by opposed, phalanx, #support and rank Score Connected[2][2][3][RANK_NB]; - // Doubled pawn penalty - constexpr Score Doubled = S(13, 40); - // Strength of pawn shelter for our king by [distance from edge][rank]. // RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king. constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = { - { V( 7), V(76), V(84), V( 38), V( 7), V( 30), V(-19) }, - { V(-3), V(93), V(52), V(-17), V(12), V(-22), V(-35) }, - { V(-6), V(83), V(25), V(-24), V(15), V( 22), V(-39) }, - { V(11), V(83), V(19), V( 8), V(18), V(-21), V(-30) } + { V( -6), V( 81), V( 93), V( 58), V( 39), V( 18), V( 25) }, + { V(-43), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) }, + { V(-10), V( 75), V( 23), V( -2), V( 32), V( 3), V( -45) }, + { V(-39), V(-13), V(-29), V(-52), V(-48), V(-67), V(-166) } }; - // Danger of enemy pawns moving toward our king by [type][distance from edge][rank]. - // For the unopposed and unblocked cases, RANK_1 = 0 is used when opponent has - // no pawn on the given file, or their pawn is behind our king. - constexpr Value StormDanger[][4][RANK_NB] = { - { { V(11), V( 79), V(132), V( 68), V( 33) }, // Unopposed - { V( 4), V(104), V(155), V( 4), V( 21) }, - { V(-7), V( 59), V(142), V( 45), V( 30) }, - { V( 0), V( 62), V(113), V( 43), V( 13) } }, - { { V( 0), V( 0), V( 37), V( 5), V(-48) }, // BlockedByPawn - { V( 0), V( 0), V( 68), V(-12), V( 13) }, - { V( 0), V( 0), V(111), V(-25), V( -3) }, - { V( 0), V( 0), V(108), V( 14), V( 21) } }, - { { V(38), V( 78), V( 83), V( 35), V( 22) }, // Unblocked - { V(33), V(-15), V(108), V( 12), V( 28) }, - { V( 8), V( 25), V( 94), V( 68), V( 25) }, - { V( 6), V( 48), V(120), V( 68), V( 40) } } + // Danger of enemy pawns moving toward our king by [distance from edge][rank]. + // RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn + // is behind our king. + constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = { + { V( 89), V(107), V(123), V(93), V(57), V( 45), V( 51) }, + { V( 44), V(-18), V(123), V(46), V(39), V( -7), V( 23) }, + { V( 4), V( 52), V(162), V(37), V( 7), V(-14), V( -2) }, + { V(-10), V(-14), V( 90), V(15), V( 2), V( -7), V(-16) } }; #undef S @@ -79,7 +67,7 @@ namespace { constexpr Color Them = (Us == WHITE ? BLACK : WHITE); constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH); - Bitboard b, neighbours, stoppers, doubled, supported, phalanx; + Bitboard b, neighbours, stoppers, doubled, support, phalanx; Bitboard lever, leverPush; Square s; bool opposed, backward; @@ -114,7 +102,7 @@ namespace { doubled = ourPawns & (s - Up); neighbours = ourPawns & adjacent_files_bb(f); phalanx = neighbours & rank_bb(s); - supported = neighbours & rank_bb(s - Up); + support = neighbours & rank_bb(s - Up); // A pawn is backward when it is behind all pawns of the same color // on the adjacent files and cannot be safely advanced. @@ -126,23 +114,22 @@ namespace { // which could become passed after one or two pawn pushes when are // not attacked more times than defended. if ( !(stoppers ^ lever ^ leverPush) - && !(ourPawns & forward_file_bb(Us, s)) - && popcount(supported) >= popcount(lever) - 1 - && popcount(phalanx) >= popcount(leverPush)) + && popcount(support) >= popcount(lever) - 1 + && popcount(phalanx) >= popcount(leverPush)) e->passedPawns[Us] |= s; else if ( stoppers == SquareBB[s + Up] && relative_rank(Us, s) >= RANK_5) { - b = shift(supported) & ~theirPawns; + b = shift(support) & ~theirPawns; while (b) if (!more_than_one(theirPawns & PawnAttacks[Us][pop_lsb(&b)])) e->passedPawns[Us] |= s; } // Score this pawn - if (supported | phalanx) - score += Connected[opposed][bool(phalanx)][popcount(supported)][relative_rank(Us, s)]; + if (support | phalanx) + score += Connected[opposed][bool(phalanx)][popcount(support)][relative_rank(Us, s)]; else if (!neighbours) score -= Isolated, e->weakUnopposed[Us] += !opposed; @@ -150,7 +137,7 @@ namespace { else if (backward) score -= Backward, e->weakUnopposed[Us] += !opposed; - if (doubled && !supported) + if (doubled && !support) score -= Doubled; } @@ -198,7 +185,6 @@ Entry* probe(const Position& pos) { e->key = key; e->scores[WHITE] = evaluate(pos, e); e->scores[BLACK] = evaluate(pos, e); - e->openFiles = popcount(e->semiopenFiles[WHITE] & e->semiopenFiles[BLACK]); e->asymmetry = popcount( (e->passedPawns[WHITE] | e->passedPawns[BLACK]) | (e->semiopenFiles[WHITE] ^ e->semiopenFiles[BLACK])); @@ -212,34 +198,30 @@ Entry* probe(const Position& pos) { template Value Entry::evaluate_shelter(const Position& pos, Square ksq) { - enum { Unopposed, BlockedByPawn, Unblocked }; constexpr Color Them = (Us == WHITE ? BLACK : WHITE); constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); constexpr Bitboard BlockRanks = (Us == WHITE ? Rank1BB | Rank2BB : Rank8BB | Rank7BB); - Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq)); + Bitboard b = pos.pieces(PAWN) & ~forward_ranks_bb(Them, ksq); Bitboard ourPawns = b & pos.pieces(Us); Bitboard theirPawns = b & pos.pieces(Them); - Value safety = (ourPawns & file_bb(ksq)) ? Value(5) : Value(-5); - - if (shift(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) - safety += 374; + Value safety = (shift(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) ? + Value(374) : Value(5); File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq))); for (File f = File(center - 1); f <= File(center + 1); ++f) { b = ourPawns & file_bb(f); - Rank rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1; + Rank ourRank = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1; b = theirPawns & file_bb(f); - Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1; + Rank theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1; int d = std::min(f, ~f); - safety += ShelterStrength[d][rkUs] - - StormDanger[rkUs == RANK_1 ? Unopposed : - rkUs == rkThem - 1 ? BlockedByPawn : Unblocked] - [d][rkThem]; + safety += ShelterStrength[d][ourRank]; + safety -= (ourRank && (ourRank == theirRank - 1)) ? 66 * (theirRank == RANK_3) + : UnblockedStorm[d][theirRank]; } return safety; @@ -250,30 +232,31 @@ Value Entry::evaluate_shelter(const Position& pos, Square ksq) { /// when king square changes, which is about 20% of total king_safety() calls. template -Score Entry::do_king_safety(const Position& pos, Square ksq) { +Score Entry::do_king_safety(const Position& pos) { + Square ksq = pos.square(Us); kingSquares[Us] = ksq; - castlingRights[Us] = pos.can_castle(Us); + castlingRights[Us] = pos.castling_rights(Us); int minKingPawnDistance = 0; Bitboard pawns = pos.pieces(Us, PAWN); if (pawns) - while (!(DistanceRingBB[ksq][minKingPawnDistance++] & pawns)) {} + while (!(DistanceRingBB[ksq][++minKingPawnDistance] & pawns)) {} Value bonus = evaluate_shelter(pos, ksq); // If we can castle use the bonus after the castling if it is bigger - if (pos.can_castle(MakeCastling::right)) + if (pos.can_castle(Us | KING_SIDE)) bonus = std::max(bonus, evaluate_shelter(pos, relative_square(Us, SQ_G1))); - if (pos.can_castle(MakeCastling::right)) + if (pos.can_castle(Us | QUEEN_SIDE)) bonus = std::max(bonus, evaluate_shelter(pos, relative_square(Us, SQ_C1))); return make_score(bonus, -16 * minKingPawnDistance); } // Explicit template instantiation -template Score Entry::do_king_safety(const Position& pos, Square ksq); -template Score Entry::do_king_safety(const Position& pos, Square ksq); +template Score Entry::do_king_safety(const Position& pos); +template Score Entry::do_king_safety(const Position& pos); } // namespace Pawns