X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=510ee167801bac972aca4b6133929c1903ae3c7f;hp=03b422f8b1155252a7a8930eae5e87a5523fc377;hb=b24bd762b2aff6cac30e1ae673775ea6f6aa8d11;hpb=9f8f093fd63f612ff28ca8b4812d0701f6d64ea7 diff --git a/src/pawns.cpp b/src/pawns.cpp index 03b422f8..510ee167 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -32,16 +32,13 @@ namespace { #define S(mg, eg) make_score(mg, eg) // Isolated pawn penalty by opposed flag - const Score Isolated[2] = { S(45, 40), S(30, 27) }; + const Score Isolated[] = { S(27, 30), S(13, 18) }; // Backward pawn penalty by opposed flag - const Score Backward[2] = { S(56, 33), S(41, 19) }; + const Score Backward[] = { S(40, 26), S(24, 12) }; - // Unsupported pawn penalty for pawns which are neither isolated or backward - const Score Unsupported = S(17, 8); - - // Connected pawn bonus by opposed, phalanx, twice supported and rank - Score Connected[2][2][2][RANK_NB]; + // Connected pawn bonus by opposed, phalanx, #support and rank + Score Connected[2][2][3][RANK_NB]; // Doubled pawn penalty const Score Doubled = S(18, 38); @@ -99,13 +96,13 @@ namespace { const Square Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST); Bitboard b, neighbours, stoppers, doubled, supported, phalanx; + Bitboard lever, leverPush; Square s; - bool opposed, lever, connected, backward; + bool opposed, backward; Score score = SCORE_ZERO; const Square* pl = pos.squares(Us); - const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)]; - Bitboard ourPawns = pos.pieces(Us , PAWN); + Bitboard ourPawns = pos.pieces( Us, PAWN); Bitboard theirPawns = pos.pieces(Them, PAWN); e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0; @@ -126,14 +123,14 @@ namespace { e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s); // Flag the pawn - opposed = theirPawns & forward_bb(Us, s); + opposed = theirPawns & forward_file_bb(Us, s); stoppers = theirPawns & passed_pawn_mask(Us, s); - lever = theirPawns & pawnAttacksBB[s]; - doubled = ourPawns & (s + Up); + lever = theirPawns & PawnAttacks[Us][s]; + leverPush = theirPawns & PawnAttacks[Us][s + Up]; + doubled = ourPawns & (s - Up); neighbours = ourPawns & adjacent_files_bb(f); phalanx = neighbours & rank_bb(s); supported = neighbours & rank_bb(s - Up); - connected = supported | phalanx; // A pawn is backward when it is behind all pawns of the same color on the // adjacent files and cannot be safely advanced. @@ -149,28 +146,39 @@ namespace { // stopper on adjacent file which controls the way to that rank. backward = (b | shift(b & adjacent_files_bb(f))) & stoppers; - assert(!backward || !(pawn_attack_span(Them, s + Up) & neighbours)); + assert(!(backward && (forward_ranks_bb(Them, s + Up) & neighbours))); } // Passed pawns will be properly scored in evaluation because we need - // full attack info to evaluate them. - if (!stoppers && !(ourPawns & forward_bb(Us, s))) + // full attack info to evaluate them. Include also not passed pawns + // 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) + && popcount(phalanx) >= popcount(leverPush)) e->passedPawns[Us] |= s; + else if ( stoppers == SquareBB[s + Up] + && relative_rank(Us, s) >= RANK_5) + { + b = shift(supported) & ~theirPawns; + while (b) + if (!more_than_one(theirPawns & PawnAttacks[Us][pop_lsb(&b)])) + e->passedPawns[Us] |= s; + } + // Score this pawn - if (!neighbours) + if (supported | phalanx) + score += Connected[opposed][!!phalanx][popcount(supported)][relative_rank(Us, s)]; + + else if (!neighbours) score -= Isolated[opposed]; else if (backward) score -= Backward[opposed]; - else if (!supported) - score -= Unsupported; - - if (connected) - score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)]; - - if (doubled) + if (doubled && !supported) score -= Doubled; if (lever) @@ -194,12 +202,13 @@ void init() { for (int opposed = 0; opposed <= 1; ++opposed) for (int phalanx = 0; phalanx <= 1; ++phalanx) - for (int apex = 0; apex <= 1; ++apex) + for (int support = 0; support <= 2; ++support) for (Rank r = RANK_2; r < RANK_8; ++r) { - int v = (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed; - v += (apex ? v / 2 : 0); - Connected[opposed][phalanx][apex][r] = make_score(v, v * (r-2) / 4); + int v = 17 * support; + v += (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed; + + Connected[opposed][phalanx][support][r] = make_score(v, v * (r - 2) / 4); } } @@ -235,7 +244,7 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) { enum { BlockedByKing, Unopposed, BlockedByPawn, Unblocked }; - Bitboard b = pos.pieces(PAWN) & (in_front_bb(Us, rank_of(ksq)) | rank_bb(ksq)); + Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq)); Bitboard ourPawns = b & pos.pieces(Us); Bitboard theirPawns = b & pos.pieces(Them); Value safety = MaxSafetyBonus; @@ -246,15 +255,16 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) { b = ourPawns & file_bb(f); Rank rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1; - b = theirPawns & file_bb(f); + b = theirPawns & file_bb(f); Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1; - safety -= ShelterWeakness[std::min(f, FILE_H - f)][rkUs] + int d = std::min(f, FILE_H - f); + safety -= ShelterWeakness[d][rkUs] + StormDanger [f == file_of(ksq) && rkThem == relative_rank(Us, ksq) + 1 ? BlockedByKing : rkUs == RANK_1 ? Unopposed : rkThem == rkUs + 1 ? BlockedByPawn : Unblocked] - [std::min(f, FILE_H - f)][rkThem]; + [d][rkThem]; } return safety;