X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=b1a85a0fcb67cb1692db334b09d437fca3ee356f;hp=b380dbf074874717e93d5adfcfc6f3d80f54f2b3;hb=1d09ee70f7da1f9aa60c7ff97a35881327f69a03;hpb=04be84e0e296d0829aa838c512fc95bf495ce629 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index b380dbf0..b1a85a0f 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -24,7 +24,7 @@ #include #include -#include "bitcount.h" +#include "bitboard.h" #include "evaluate.h" #include "material.h" #include "pawns.h" @@ -77,6 +77,11 @@ namespace { // attacked by a given color and piece type (can be also ALL_PIECES). Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB]; + // attackedBy2[color] are the squares attacked by 2 pieces of a given color, + // possibly via x-ray or by one pawn and one piece. Diagonal x-ray through + // pawn or squares attacked by 2 pawns are not explicitly added. + Bitboard attackedBy2[COLOR_NB]; + // kingRing[color] is the zone around the king which is considered // by the king safety evaluation. This consists of the squares directly // adjacent to the king, and the three (or two, for a king on an edge file) @@ -132,21 +137,21 @@ namespace { // Outpost[knight/bishop][supported by pawn] contains bonuses for knights and // bishops outposts, bigger if outpost piece is supported by a pawn. const Score Outpost[][2] = { - { S(42,11), S(63,17) }, // Knights - { S(18, 5), S(27, 8) } // Bishops + { S(43,11), S(65,20) }, // Knights + { S(20, 3), S(29, 8) } // Bishops }; // ReachableOutpost[knight/bishop][supported by pawn] contains bonuses for // knights and bishops which can reach an outpost square in one move, bigger // if outpost square is supported by a pawn. const Score ReachableOutpost[][2] = { - { S(21, 5), S(31, 8) }, // Knights - { S( 8, 2), S(13, 4) } // Bishops + { S(21, 5), S(35, 8) }, // Knights + { S( 8, 0), S(14, 4) } // Bishops }; // RookOnFile[semiopen/open] contains bonuses for each rook when there is no // friendly pawn on the rook file. - const Score RookOnFile[2] = { S(19, 10), S(43, 21) }; + const Score RookOnFile[2] = { S(20, 7), S(45, 20) }; // ThreatBySafePawn[PieceType] contains bonuses according to which piece // type is attacked by a pawn which is protected or is not attacked. @@ -169,7 +174,7 @@ namespace { // We don't use a Score because we process the two components independently. const Value Passed[][RANK_NB] = { { V(5), V( 5), V(31), V(73), V(166), V(252) }, - { V(7), V(14), V(38), V(64), V(137), V(193) } + { V(7), V(14), V(38), V(73), V(166), V(252) } }; // PassedFile[File] contains a bonus according to the file of a passed pawn @@ -181,12 +186,15 @@ namespace { // Assorted bonuses and penalties used by evaluation const Score MinorBehindPawn = S(16, 0); const Score BishopPawns = S( 8, 12); - const Score RookOnPawn = S( 7, 27); + const Score RookOnPawn = S( 8, 24); const Score TrappedRook = S(92, 0); - const Score Checked = S(20, 20); - const Score ThreatByHangingPawn = S(70, 63); - const Score Hanging = S(48, 28); - const Score ThreatByPawnPush = S(31, 19); + const Score SafeCheck = S(20, 20); + const Score OtherCheck = S(10, 10); + const Score ThreatByHangingPawn = S(71, 61); + const Score LooseEnemies = S( 0, 25); + const Score WeakQueen = S(35, 0); + const Score Hanging = S(48, 27); + const Score ThreatByPawnPush = S(38, 22); const Score Unstoppable = S( 0, 20); // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by @@ -208,10 +216,10 @@ namespace { // Penalties for enemy's safe checks const int QueenContactCheck = 89; - const int QueenCheck = 50; - const int RookCheck = 45; - const int BishopCheck = 6; - const int KnightCheck = 14; + const int QueenCheck = 62; + const int RookCheck = 57; + const int BishopCheck = 48; + const int KnightCheck = 78; // eval_init() initializes king and attack bitboards for a given color @@ -224,16 +232,17 @@ namespace { const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); ei.pinnedPieces[Us] = pos.pinned_pieces(Us); - Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.square(Them)); + Bitboard b = ei.attackedBy[Them][KING]; ei.attackedBy[Them][ALL_PIECES] |= b; ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); + ei.attackedBy2[Us] = ei.attackedBy[Us][PAWN] & ei.attackedBy[Us][KING]; // Init king safety tables only if we are going to use them if (pos.non_pawn_material(Us) >= QueenValueMg) { ei.kingRing[Them] = b | shift_bb(b); b &= ei.attackedBy[Us][PAWN]; - ei.kingAttackersCount[Us] = b ? popcount(b) : 0; + ei.kingAttackersCount[Us] = popcount(b); ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0; } else @@ -269,15 +278,14 @@ namespace { if (ei.pinnedPieces[Us] & s) b &= LineBB[pos.square(Us)][s]; + ei.attackedBy2[Us] |= ei.attackedBy[Us][ALL_PIECES] & b; ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; if (b & ei.kingRing[Them]) { ei.kingAttackersCount[Us]++; ei.kingAttackersWeight[Us] += KingAttackWeights[Pt]; - bb = b & ei.attackedBy[Them][KING]; - if (bb) - ei.kingAdjacentZoneAttacksCount[Us] += popcount(bb); + ei.kingAdjacentZoneAttacksCount[Us] += popcount(b & ei.attackedBy[Them][KING]); } if (Pt == QUEEN) @@ -285,7 +293,7 @@ namespace { | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); - int mob = popcount(b & mobilityArea[Us]); + int mob = popcount(b & mobilityArea[Us]); mobility[Us] += MobilityBonus[Pt][mob]; @@ -330,11 +338,7 @@ namespace { { // Bonus for aligning with enemy pawns on the same rank/file if (relative_rank(Us, s) >= RANK_5) - { - Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; - if (alignedPawns) - score += RookOnPawn * popcount(alignedPawns); - } + score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]); // Bonus when on an open or semi-open file if (ei.pi->semiopen_file(Us, file_of(s))) @@ -351,6 +355,13 @@ namespace { score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); } } + + if (Pt == QUEEN) + { + // Penalty if any relative pin or discovered attack against the queen + if (pos.slider_blockers(pos.pieces(), pos.pieces(Them, ROOK, BISHOP), s)) + score -= WeakQueen; + } } if (DoTrace) @@ -371,9 +382,10 @@ namespace { template Score evaluate_king(const Position& pos, const EvalInfo& ei) { - const Color Them = (Us == WHITE ? BLACK : WHITE); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Square Up = (Us == WHITE ? DELTA_N : DELTA_S); - Bitboard undefended, b, b1, b2, safe; + Bitboard undefended, b, b1, b2, safe, other; int attackUnits; const Square ksq = pos.square(Us); @@ -383,13 +395,14 @@ namespace { // Main king safety evaluation if (ei.kingAttackersCount[Them]) { - // Find the attacked squares around the king which have no defenders - // apart from the king itself. - undefended = ei.attackedBy[Them][ALL_PIECES] - & ei.attackedBy[Us][KING] - & ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] - | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK] - | ei.attackedBy[Us][QUEEN]); + // Find the attacked squares which are defended only by the king... + undefended = ei.attackedBy[Them][ALL_PIECES] + & ei.attackedBy[Us][KING] + & ~ei.attackedBy2[Us]; + + // ... and those which are not defended at all in the larger king ring + b = ei.attackedBy[Them][ALL_PIECES] & ~ei.attackedBy[Us][ALL_PIECES] + & ei.kingRing[Us] & ~pos.pieces(Them); // Initialize the 'attackUnits' variable, which is used later on as an // index into the KingDanger[] array. The initial value is based on the @@ -398,46 +411,60 @@ namespace { // the pawn shelter (current 'score' value). attackUnits = std::min(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) + 9 * ei.kingAdjacentZoneAttacksCount[Them] - + 27 * popcount(undefended) - + 11 * !!ei.pinnedPieces[Us] + + 21 * popcount(undefended) + + 12 * (popcount(b) + !!ei.pinnedPieces[Us]) - 64 * !pos.count(Them) - mg_value(score) / 8; // Analyse the enemy's safe queen contact checks. Firstly, find the // undefended squares around the king reachable by the enemy queen... b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them); - if (b) - { - // ...and then remove squares not supported by another enemy piece - b &= ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] - | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK] - | ei.attackedBy[Them][KING]; - if (b) - attackUnits += QueenContactCheck * popcount(b); - } + // ...and keep squares supported by another enemy piece + attackUnits += QueenContactCheck * popcount(b & ei.attackedBy2[Them]); + + // Analyse the safe enemy's checks which are possible on next move... + safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - // Analyse the enemy's safe distance checks for sliders and knights - safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); + // ... and some other potential checks, only requiring the square to be + // safe from pawn-attacks, and not being occupied by a blocked pawn. + other = ~( ei.attackedBy[Us][PAWN] + | (pos.pieces(Them, PAWN) & shift_bb(pos.pieces(PAWN)))); - b1 = pos.attacks_from(ksq) & safe; - b2 = pos.attacks_from(ksq) & safe; + b1 = pos.attacks_from(ksq); + b2 = pos.attacks_from(ksq); // Enemy queen safe checks - if ((b1 | b2) & ei.attackedBy[Them][QUEEN]) - attackUnits += QueenCheck, score -= Checked; + if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe) + attackUnits += QueenCheck, score -= SafeCheck; + + // For other pieces, also consider the square safe if attacked twice, + // and only defended by a queen. + safe |= ei.attackedBy2[Them] + & ~(ei.attackedBy2[Us] | pos.pieces(Them)) + & ei.attackedBy[Us][QUEEN]; - // Enemy rooks safe checks - if (b1 & ei.attackedBy[Them][ROOK]) - attackUnits += RookCheck, score -= Checked; + // Enemy rooks safe and other checks + if (b1 & ei.attackedBy[Them][ROOK] & safe) + attackUnits += RookCheck, score -= SafeCheck; - // Enemy bishops safe checks - if (b2 & ei.attackedBy[Them][BISHOP]) - attackUnits += BishopCheck, score -= Checked; + else if (b1 & ei.attackedBy[Them][ROOK] & other) + score -= OtherCheck; - // Enemy knights safe checks - if (pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe) - attackUnits += KnightCheck, score -= Checked; + // Enemy bishops safe and other checks + if (b2 & ei.attackedBy[Them][BISHOP] & safe) + attackUnits += BishopCheck, score -= SafeCheck; + + else if (b2 & ei.attackedBy[Them][BISHOP] & other) + score -= OtherCheck; + + // Enemy knights safe and other checks + b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT]; + if (b & safe) + attackUnits += KnightCheck, score -= SafeCheck; + + else if (b & other) + score -= OtherCheck; // Finally, extract the king danger score from the KingDanger[] // array and subtract the score from the evaluation. @@ -464,11 +491,28 @@ namespace { const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + const Bitboard TheirCamp = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB + : Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB); + + const Bitboard QueenSide = TheirCamp & (FileABB | FileBBB | FileCBB | FileDBB); + const Bitboard CenterFiles = TheirCamp & (FileCBB | FileDBB | FileEBB | FileFBB); + const Bitboard KingSide = TheirCamp & (FileEBB | FileFBB | FileGBB | FileHBB); + + const Bitboard KingFlank[FILE_NB] = { + QueenSide, QueenSide, QueenSide, CenterFiles, + CenterFiles, KingSide, KingSide, KingSide + }; + enum { Minor, Rook }; Bitboard b, weak, defended, safeThreats; Score score = SCORE_ZERO; + // Small bonus if the opponent has loose pawns or pieces + if ( (pos.pieces(Them) ^ pos.pieces(Them, QUEEN, KING)) + & ~(ei.attackedBy[Us][ALL_PIECES] | ei.attackedBy[Them][ALL_PIECES])) + score += LooseEnemies; + // Non-pawn enemies attacked by a pawn weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN]; @@ -505,9 +549,7 @@ namespace { while (b) score += Threat[Rook ][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weak & ~ei.attackedBy[Them][ALL_PIECES]; - if (b) - score += Hanging * popcount(b); + score += Hanging * popcount(weak & ~ei.attackedBy[Them][ALL_PIECES]); b = weak & ei.attackedBy[Us][KING]; if (b) @@ -526,8 +568,19 @@ namespace { & pos.pieces(Them) & ~ei.attackedBy[Us][PAWN]; - if (b) - score += ThreatByPawnPush * popcount(b); + score += ThreatByPawnPush * popcount(b); + + // King tropism: firstly, find squares that we attack in the enemy king flank + b = ei.attackedBy[Us][ALL_PIECES] & KingFlank[file_of(pos.square(Them))]; + + // Secondly, add to the bitboard the squares which we attack twice in that flank + // but which are not protected by a enemy pawn. Note the trick to shift away the + // previous attack bits to the empty part of the bitboard. + b = (b & ei.attackedBy2[Us] & ~ei.attackedBy[Them][PAWN]) + | (Us == WHITE ? b >> 4 : b << 4); + + // Count all these squares with a single popcount + score += make_score(7 * popcount(b), 0); if (DoTrace) Trace::add(THREAT, Us, score); @@ -553,6 +606,7 @@ namespace { Square s = pop_lsb(&b); assert(pos.pawn_passed(Us, s)); + assert(!(pos.pieces(PAWN) & forward_bb(Us, s))); int r = relative_rank(Us, s) - RANK_2; int rr = r * (r - 1); @@ -605,9 +659,6 @@ namespace { mbonus += rr + r * 2, ebonus += rr + r * 2; } // rr != 0 - if (pos.count(Us) < pos.count(Them)) - ebonus += ebonus / 4; - score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; } @@ -650,7 +701,7 @@ namespace { assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); // ...count safe + (behind & safe) with a single popcount - int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); + int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); int weight = pos.count(Us) + pos.count(Us) + pos.count(Them) + pos.count(Them); @@ -701,7 +752,7 @@ namespace { // Endgame with opposite-colored bishops, but also other pieces. Still // a bit drawish, but not as drawish as with only the two bishops. else - sf = ScaleFactor(46 * sf / SCALE_FACTOR_NORMAL); + sf = ScaleFactor(46); } // Endings where weaker side can place his king in front of the opponent's // pawns are drawish. @@ -748,6 +799,8 @@ Value Eval::evaluate(const Position& pos) { // Initialize attack and king safety bitboards ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; + ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.square(WHITE)); + ei.attackedBy[BLACK][KING] = pos.attacks_from(pos.square(BLACK)); eval_init(pos, ei); eval_init(pos, ei);