X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=3095838820632331b5f5ac805dd5ed867af83cf9;hp=489422fc96f163770aa71791f987baa6d4b0a8a4;hb=8662bdfa124ae3ec90d9bf88842d9cfab9a43532;hpb=f619f1d38c3d77c315b509ae2fe637926c9059fd diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 489422fc..30958388 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -119,7 +119,7 @@ namespace { // game, indexed by piece type and number of attacked squares in the MobilityArea. const Score MobilityBonus[][32] = { {}, {}, - { S(-75,-76), S(-56,-54), S(- 9,-26), S( -2,-10), S( 6, 5), S( 15, 11), // Knights + { S(-75,-76), S(-56,-54), S( -9,-26), S( -2,-10), S( 6, 5), S( 15, 11), // Knights S( 22, 26), S( 30, 28), S( 36, 29) }, { S(-48,-58), S(-21,-19), S( 16, -2), S( 26, 12), S( 37, 22), S( 51, 42), // Bishops S( 54, 54), S( 63, 58), S( 65, 63), S( 71, 70), S( 79, 74), S( 81, 86), @@ -188,6 +188,7 @@ namespace { const Score BishopPawns = S( 8, 12); const Score RookOnPawn = S( 8, 24); const Score TrappedRook = S(92, 0); + const Score CloseEnemies = S( 7, 0); const Score SafeCheck = S(20, 20); const Score OtherCheck = S(10, 10); const Score ThreatByHangingPawn = S(71, 61); @@ -205,21 +206,15 @@ namespace { #undef S #undef V - // King danger constants and variables. The king danger scores are looked-up - // in KingDanger[]. Various little "meta-bonuses" measuring the strength - // of the enemy attack are added up into an integer, which is used as an - // index to KingDanger[]. - Score KingDanger[512]; - // KingAttackWeights[PieceType] contains king attack weights by piece type - const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 7, 5, 4, 1 }; + const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 }; // Penalties for enemy's safe checks - const int QueenContactCheck = 89; - const int QueenCheck = 62; - const int RookCheck = 57; - const int BishopCheck = 48; - const int KnightCheck = 78; + const int QueenContactCheck = 997; + const int QueenCheck = 695; + const int RookCheck = 638; + const int BishopCheck = 538; + const int KnightCheck = 874; // eval_init() initializes king and attack bitboards for a given color @@ -359,7 +354,8 @@ namespace { 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)) + Bitboard pinners; + if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s, pinners)) score -= WeakQueen; } } @@ -379,6 +375,19 @@ namespace { // evaluate_king() assigns bonuses and penalties to a king of a given color + const Bitboard WhiteCamp = Rank1BB | Rank2BB | Rank3BB | Rank4BB | Rank5BB; + const Bitboard BlackCamp = Rank8BB | Rank7BB | Rank6BB | Rank5BB | Rank4BB; + const Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; + const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; + const Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; + + const Bitboard KingFlank[COLOR_NB][FILE_NB] = { + { QueenSide & WhiteCamp, QueenSide & WhiteCamp, QueenSide & WhiteCamp, CenterFiles & WhiteCamp, + CenterFiles & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp }, + { QueenSide & BlackCamp, QueenSide & BlackCamp, QueenSide & BlackCamp, CenterFiles & BlackCamp, + CenterFiles & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp }, + }; + template Score evaluate_king(const Position& pos, const EvalInfo& ei) { @@ -386,7 +395,7 @@ namespace { const Square Up = (Us == WHITE ? DELTA_N : DELTA_S); Bitboard undefended, b, b1, b2, safe, other; - int attackUnits; + int kingDanger; const Square ksq = pos.square(Us); // King shelter and enemy pawns storm @@ -404,24 +413,24 @@ namespace { 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 + // Initialize the 'kingDanger' variable, which will be transformed + // later into a king danger score. The initial value is based on the // number and types of the enemy's attacking pieces, the number of // attacked and undefended squares around our king and the quality of // the pawn shelter (current 'score' value). - attackUnits = std::min(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) - + 9 * ei.kingAdjacentZoneAttacksCount[Them] - + 21 * popcount(undefended) - + 12 * (popcount(b) + !!ei.pinnedPieces[Us]) - - 64 * !pos.count(Them) - - mg_value(score) / 8; + kingDanger = std::min(807, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) + + 101 * ei.kingAdjacentZoneAttacksCount[Them] + + 235 * popcount(undefended) + + 134 * (popcount(b) + !!ei.pinnedPieces[Us]) + - 717 * !pos.count(Them) + - 7 * mg_value(score) / 5 - 5; // 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); // ...and keep squares supported by another enemy piece - attackUnits += QueenContactCheck * popcount(b & ei.attackedBy2[Them]); + kingDanger += 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)); @@ -436,7 +445,7 @@ namespace { // Enemy queen safe checks if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe) - attackUnits += QueenCheck, score -= SafeCheck; + kingDanger += QueenCheck, score -= SafeCheck; // For other pieces, also consider the square safe if attacked twice, // and only defended by a queen. @@ -446,14 +455,14 @@ namespace { // Enemy rooks safe and other checks if (b1 & ei.attackedBy[Them][ROOK] & safe) - attackUnits += RookCheck, score -= SafeCheck; + kingDanger += RookCheck, score -= SafeCheck; else if (b1 & ei.attackedBy[Them][ROOK] & other) score -= OtherCheck; // Enemy bishops safe and other checks if (b2 & ei.attackedBy[Them][BISHOP] & safe) - attackUnits += BishopCheck, score -= SafeCheck; + kingDanger += BishopCheck, score -= SafeCheck; else if (b2 & ei.attackedBy[Them][BISHOP] & other) score -= OtherCheck; @@ -461,16 +470,29 @@ namespace { // Enemy knights safe and other checks b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT]; if (b & safe) - attackUnits += KnightCheck, score -= SafeCheck; + kingDanger += 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. - score -= KingDanger[std::max(std::min(attackUnits, 399), 0)]; + // Compute the king danger score and subtract it from the evaluation + if (kingDanger > 0) + score -= make_score(std::min(kingDanger * kingDanger / 4096, 2 * int(BishopValueMg)), 0); } + // King tropism: firstly, find squares that opponent attacks in our king flank + b = ei.attackedBy[Them][ALL_PIECES] & KingFlank[Us][file_of(ksq)]; + + assert(((Us == WHITE ? b << 4 : b >> 4) & b) == 0); + assert(popcount(Us == WHITE ? b << 4 : b >> 4) == popcount(b)); + + // Secondly, add the squares which are attacked twice in that flank and + // which are not defended by our pawns. + b = (Us == WHITE ? b << 4 : b >> 4) + | (b & ei.attackedBy2[Them] & ~ei.attackedBy[Us][PAWN]); + + score -= CloseEnemies * popcount(b); + if (DoTrace) Trace::add(KING, Us, score); @@ -481,19 +503,6 @@ namespace { // evaluate_threats() assigns bonuses according to the types of the attacking // and the attacked pieces. - const Bitboard WhiteCamp = Rank4BB | Rank5BB | Rank6BB | Rank7BB | Rank8BB; - const Bitboard BlackCamp = Rank5BB | Rank4BB | Rank3BB | Rank2BB | Rank1BB; - const Bitboard QueenSide = FileABB | FileBBB | FileCBB | FileDBB; - const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB; - const Bitboard KingSide = FileEBB | FileFBB | FileGBB | FileHBB; - - const Bitboard KingFlank[COLOR_NB][FILE_NB] = { - { QueenSide & WhiteCamp, QueenSide & WhiteCamp, QueenSide & WhiteCamp, CenterFiles & WhiteCamp, - CenterFiles & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp, KingSide & WhiteCamp }, - { QueenSide & BlackCamp, QueenSide & BlackCamp, QueenSide & BlackCamp, CenterFiles & BlackCamp, - CenterFiles & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp, KingSide & BlackCamp }, - }; - template Score evaluate_threats(const Position& pos, const EvalInfo& ei) { @@ -571,18 +580,6 @@ namespace { score += ThreatByPawnPush * popcount(b); - // King tropism: firstly, find squares that we attack in the enemy king flank - b = ei.attackedBy[Us][ALL_PIECES] & KingFlank[Us][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); @@ -703,10 +700,10 @@ namespace { // ...count safe + (behind & safe) with a single popcount 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); + bonus = std::min(16, bonus); + int weight = pos.count(Us) - 2 * ei.pi->open_files(); - return make_score(bonus * weight * weight * 2 / 11, 0); + return make_score(bonus * weight * weight / 18, 0); } @@ -758,9 +755,9 @@ namespace { // Endings where weaker side can place his king in front of the opponent's // pawns are drawish. else if ( abs(eg) <= BishopValueEg - && ei.pi->pawn_span(strongSide) <= 1 + && pos.count(strongSide) <= 2 && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) - sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37); + sf = ScaleFactor(37 + 7 * pos.count(strongSide)); } return sf; @@ -777,23 +774,22 @@ Value Eval::evaluate(const Position& pos) { assert(!pos.checkers()); + Score mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; EvalInfo ei; - Score score, mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; - - // Initialize score by reading the incrementally updated scores included in - // the position object (material + piece square tables). Score is computed - // internally from the white point of view. - score = pos.psq_score(); // Probe the material hash table ei.me = Material::probe(pos); - score += ei.me->imbalance(); // If we have a specialized evaluation function for the current material // configuration, call it and return. if (ei.me->specialized_eval_exists()) return ei.me->evaluate(pos); + // Initialize score by reading the incrementally updated scores included in + // the position object (material + piece square tables) and the material + // imbalance. Score is computed internally from the white point of view. + Score score = pos.psq_score() + ei.me->imbalance(); + // Probe the pawn hash table ei.pi = Pawns::probe(pos); score += ei.pi->pawns_score(); @@ -918,19 +914,3 @@ std::string Eval::trace(const Position& pos) { return ss.str(); } - - -/// init() computes evaluation weights, usually at startup - -void Eval::init() { - - const int MaxSlope = 322; - const int Peak = 47410; - int t = 0; - - for (int i = 0; i < 400; ++i) - { - t = std::min(Peak, std::min(i * i - 16, t + MaxSlope)); - KingDanger[i] = make_score(t * 268 / 7700, 0); - } -}