X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=36b10f32f6e1606a91f69bda1964bda11a51b4cb;hp=8b997b6056b99e8a55208fb980bd8312849cbca6;hb=bc3b148d5712ef9ea00e74d3ff5aea10a4d3cabe;hpb=6634f41ac9e76fe623dd36d312b6955ab2c66a4f diff --git a/src/pawns.cpp b/src/pawns.cpp index 8b997b60..36b10f32 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -31,45 +31,37 @@ namespace { #define V Value #define S(mg, eg) make_score(mg, eg) - // Isolated pawn penalty - constexpr Score Isolated = S(13, 18); - - // Backward pawn penalty - constexpr Score Backward = S(24, 12); + // 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(18, 38); - // 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( -9), V(64), V(77), V( 44), V( 4), V( -1), V(-11) }, - { V(-15), V(83), V(51), V(-10), V( 1), V(-10), V(-28) }, - { V(-18), V(84), V(27), V(-12), V(21), V( -7), V(-36) }, - { V( 12), V(79), V(25), V( 19), V( 9), V( -6), V(-33) } + { 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( 4), V( 73), V( 132), V(46), V(31) }, // Unopposed - { V( 1), V( 64), V( 143), V(26), V(13) }, - { V( 1), V( 47), V( 110), V(44), V(24) }, - { V( 0), V( 72), V( 127), V(50), V(31) } }, - { { V( 0), V( 0), V( 19), V(23), V( 1) }, // BlockedByPawn - { V( 0), V( 0), V( 88), V(27), V( 2) }, - { V( 0), V( 0), V( 101), V(16), V( 1) }, - { V( 0), V( 0), V( 111), V(22), V(15) } }, - { { V(22), V( 45), V( 104), V(62), V( 6) }, // Unblocked - { V(31), V( 30), V( 99), V(39), V(19) }, - { V(23), V( 29), V( 96), V(41), V(15) }, - { V(21), V( 23), V( 116), V(41), V(15) } } + // 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) } }; + // Danger of blocked enemy pawns storming our king, by rank + constexpr Value BlockedStorm[RANK_NB] = + { V(0), V(0), V(66), V(6), V(5), V(1), V(15) }; + #undef S #undef V @@ -126,7 +118,6 @@ 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)) e->passedPawns[Us] |= s; @@ -212,34 +203,30 @@ 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; + int ourRank = b ? relative_rank(Us, backmost_sq(Us, b)) : 0; b = theirPawns & file_bb(f); - Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1; + int theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0; 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)) ? BlockedStorm[theirRank] + : UnblockedStorm[d][theirRank]; } return safety; @@ -258,15 +245,15 @@ Score Entry::do_king_safety(const Position& pos, Square ksq) { 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);