X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=55462bcf1ca16c2054fab08d1c80826bdc166780;hp=b8a002428d5a1a6cc4e9024438a792267b0a7d10;hb=12e79be91039796299187ba1b2f1559552642ea4;hpb=fc0a1f37cf2029af3d35221423da7ac512afbf88 diff --git a/src/pawns.cpp b/src/pawns.cpp index b8a00242..55462bcf 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, 16); - - // Backward pawn penalty - constexpr Score Backward = S(17, 11); + // Pawn penalties + constexpr Score Isolated = S( 5, 15); + constexpr Score Backward = S( 9, 24); + constexpr Score Doubled = S(11, 56); // 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( -3), V( 81), V( 93), V( 58), V( 39), V( 18), V( 25) }, + { V(-40), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) }, + { V( -7), V( 75), V( 23), V( -2), V( 32), V( 3), V( -45) }, + { V(-36), 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) } }; + // 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 @@ -212,7 +204,6 @@ 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); @@ -224,22 +215,21 @@ Value Entry::evaluate_shelter(const Position& pos, Square ksq) { Value safety = (ourPawns & file_bb(ksq)) ? Value(5) : Value(-5); if (shift(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) - safety += 374; + safety += Value(374); 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;