X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=d2aab71df68c393c5e0323d87514efdaf523aa64;hp=e39bcb4a8e99721820fa637151ace370d009f5d9;hb=fc0a1f37cf2029af3d35221423da7ac512afbf88;hpb=06a8fd2154db41c4e438a1b065c1471d0dfd5815 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index e39bcb4a..d2aab71d 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -146,23 +146,23 @@ namespace { // PassedRank[Rank] contains a bonus according to the rank of a passed pawn constexpr Score PassedRank[RANK_NB] = { - S(0, 0), S(5, 7), S(5, 13), S(32, 42), S(70, 70), S(172, 170), S(217, 269) + S(0, 0), S(5, 7), S(5, 13), S(18, 23), S(74, 58), S(164, 166), S(268, 243) }; // PassedFile[File] contains a bonus according to the file of a passed pawn constexpr Score PassedFile[FILE_NB] = { - S( 9, 10), S(2, 10), S(1, -8), S(-20,-12), - S(-20,-12), S(1, -8), S(2, 10), S( 9, 10) + S( 15, 7), S(-5, 14), S( 1, -5), S(-22,-11), + S(-22,-11), S( 1, -5), S(-5, 14), S( 15, 7) }; // PassedDanger[Rank] contains a term to weight the passed score - constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 2, 7, 12, 19 }; + constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 3, 6, 12, 21 }; // KingProtector[PieceType-2] contains a penalty according to distance from king constexpr Score KingProtector[] = { S(3, 5), S(4, 3), S(3, 0), S(1, -1) }; // Assorted bonuses and penalties - constexpr Score BishopPawns = S( 8, 12); + constexpr Score BishopPawns = S( 3, 5); constexpr Score CloseEnemies = S( 7, 0); constexpr Score Connectivity = S( 3, 1); constexpr Score CorneredBishop = S( 50, 50); @@ -171,6 +171,7 @@ namespace { constexpr Score KnightOnQueen = S( 21, 11); constexpr Score LongDiagonalBishop = S( 22, 0); constexpr Score MinorBehindPawn = S( 16, 0); + constexpr Score Overload = S( 10, 5); constexpr Score PawnlessFlank = S( 20, 80); constexpr Score RookOnPawn = S( 8, 24); constexpr Score SliderOnQueen = S( 42, 21); @@ -257,9 +258,9 @@ 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 controlled by enemy pawns + // 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.square(Us) | pe->pawn_attacks(Them)); + mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them)); // Initialise attackedBy bitboards for kings and pawns attackedBy[Us][KING] = pos.attacks_from(pos.square(Us)); @@ -292,7 +293,8 @@ namespace { template template Score Evaluation::pieces() { - constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Color Them = (Us == WHITE ? BLACK : WHITE); + constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH); constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); @@ -348,8 +350,12 @@ namespace { if (Pt == BISHOP) { - // Penalty according to number of pawns on the same color square as the bishop - score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s); + // Penalty according to number of pawns on the same color square as the + // bishop, bigger when the center files are blocked with pawns. + Bitboard blocked = pos.pieces(Us, PAWN) & shift(pos.pieces()); + + score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s) + * (1 + popcount(blocked & CenterFiles)); // Bonus for bishop on a long diagonal which can "see" both center squares if (more_than_one(Center & (attacks_bb(s, pos.pieces(PAWN)) | s))) @@ -518,16 +524,9 @@ namespace { Bitboard b, weak, defended, nonPawnEnemies, stronglyProtected, safeThreats; Score score = SCORE_ZERO; - // Non-pawn enemies attacked by a pawn + // Non-pawn enemies nonPawnEnemies = pos.pieces(Them) ^ pos.pieces(Them, PAWN); - // Our safe or protected pawns - b = pos.pieces(Us, PAWN) - & (~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]); - - safeThreats = pawn_attacks_bb(b) & nonPawnEnemies; - score += ThreatBySafePawn * popcount(safeThreats); - // Squares strongly protected by the enemy, either because they defend the // square with a pawn, or because they defend the square twice and we don't. stronglyProtected = attackedBy[Them][PAWN] @@ -560,17 +559,30 @@ namespace { score += ThreatByRank * (int)relative_rank(Them, s); } - score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]); - b = weak & attackedBy[Us][KING]; if (b) score += ThreatByKing[more_than_one(b)]; + + score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]); + + // Bonus for overload (non-pawn enemies attacked and defended exactly once) + b = nonPawnEnemies + & attackedBy[Us][ALL_PIECES] & ~attackedBy2[Us] + & attackedBy[Them][ALL_PIECES] & ~attackedBy2[Them]; + score += Overload * popcount(b); } // Bonus for enemy unopposed weak pawns if (pos.pieces(Us, ROOK, QUEEN)) score += WeakUnopposedPawn * pe->weak_unopposed(Them); + // Our safe or protected pawns + b = pos.pieces(Us, PAWN) + & (~attackedBy[Them][ALL_PIECES] | attackedBy[Us][ALL_PIECES]); + + safeThreats = pawn_attacks_bb(b) & nonPawnEnemies; + score += ThreatBySafePawn * popcount(safeThreats); + // 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(); @@ -691,7 +703,7 @@ namespace { } // w != 0 // Scale down bonus for candidate passers which need more than one - // pawn push to become passed or have a pawn in front of them. + // 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))) bonus = bonus / 2; @@ -724,13 +736,10 @@ namespace { if (pos.non_pawn_material() < SpaceThreshold) return SCORE_ZERO; - // Find the safe squares for our pieces inside the area defined by - // SpaceMask. A square is unsafe if it is attacked by an enemy - // pawn, or if it is undefended and attacked by an enemy piece. + // Find the available squares for our pieces inside the area defined by SpaceMask Bitboard safe = SpaceMask & ~pos.pieces(Us, PAWN) - & ~attackedBy[Them][PAWN] - & (attackedBy[Us][ALL_PIECES] | ~attackedBy[Them][ALL_PIECES]); + & ~attackedBy[Them][PAWN]; // Find all squares which are at most three squares behind some friendly pawn Bitboard behind = pos.pieces(Us, PAWN); @@ -790,9 +799,8 @@ namespace { Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK; int sf = me->scale_factor(pos, strongSide); - // If we don't already have an unusual scale factor, check for certain - // types of endgames, and use a lower scale for those. - if (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN) + // If scale is not already specific, scale down the endgame via general heuristics + if (sf == SCALE_FACTOR_NORMAL) { if (pos.opposite_bishops()) { @@ -806,12 +814,8 @@ namespace { else sf = 46; } - // Endings where weaker side can place his king in front of the enemy's - // pawns are drawish. - else if ( abs(eg) <= BishopValueEg - && pos.count(strongSide) <= 2 - && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) - sf = 37 + 7 * pos.count(strongSide); + else + sf = std::min(40 + 7 * pos.count(strongSide), sf); } return ScaleFactor(sf);