X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fevaluate.cpp;h=3095838820632331b5f5ac805dd5ed867af83cf9;hb=28240d375c837f2342163e84675bc9230124cd30;hp=d533eed8c76d17172c10632c2c0cdada03a5a7a6;hpb=5cffc032da8402df79cf6cba4238b83ff5d29f7e;p=stockfish diff --git a/src/evaluate.cpp b/src/evaluate.cpp index d533eed8..30958388 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -206,21 +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[400]; - // 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 @@ -360,7 +354,8 @@ namespace { if (Pt == QUEEN) { // Penalty if any relative pin or discovered attack against the queen - if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s)) + Bitboard pinners; + if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s, pinners)) score -= WeakQueen; } } @@ -400,7 +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 @@ -418,24 +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)); @@ -450,7 +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. @@ -460,14 +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; @@ -475,14 +470,14 @@ 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 @@ -706,9 +701,9 @@ namespace { // ...count safe + (behind & safe) with a single popcount int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); bonus = std::min(16, bonus); - int weight = pos.count(Us); + int weight = pos.count(Us) - 2 * ei.pi->open_files(); - return make_score(bonus * weight * weight / 22, 0); + return make_score(bonus * weight * weight / 18, 0); } @@ -779,23 +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(); @@ -920,19 +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); - } -}