X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=3e8dcc2635bfe817ea9d68e5259e354c40f08e48;hp=fe02ca29efc07cf59327428819154bf0ae0728a0;hb=69a1a808c8ed02332914afbb503f3d96fa8bb093;hpb=6fb0a1bc4050dd9b15e9c163c46c60f25c48137d diff --git a/src/evaluate.cpp b/src/evaluate.cpp index fe02ca29..3e8dcc26 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -19,6 +19,7 @@ #include #include +#include // For std::memset #include #include @@ -26,10 +27,26 @@ #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "thread.h" namespace { + namespace Tracing { + + enum Term { // First 8 entries are for PieceType + MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERM_NB + }; + + Score scores[COLOR_NB][TERM_NB]; + + std::ostream& operator<<(std::ostream& os, Term idx); + + double to_cp(Value v); + void write(int idx, Color c, Score s); + void write(int idx, Score w, Score b = SCORE_ZERO); + std::string do_trace(const Position& pos); + } + + // Struct EvalInfo contains various information computed and collected // by the evaluation functions. struct EvalInfo { @@ -57,45 +74,34 @@ namespace { // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the // given color which attack a square in the kingRing of the enemy king. The - // weights of the individual piece types are given by the variables - // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and - // KnightAttackWeight in evaluate.cpp + // weights of the individual piece types are given by the elements in the + // KingAttackWeights array. int kingAttackersWeight[COLOR_NB]; - // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares - // directly adjacent to the king of the given color. Pieces which attack - // more than one square are counted multiple times. For instance, if black's - // king is on g8 and there's a white knight on g5, this knight adds - // 2 to kingAdjacentZoneAttacksCount[BLACK]. + // kingAdjacentZoneAttacksCount[color] is the number of attacks by the given + // color to squares directly adjacent to the enemy king. Pieces which attack + // more than one square are counted multiple times. For instance, if there is + // a white knight on g5 and black's king is on g8, this white knight adds 2 + // to kingAdjacentZoneAttacksCount[WHITE]. int kingAdjacentZoneAttacksCount[COLOR_NB]; Bitboard pinnedPieces[COLOR_NB]; }; - namespace Tracing { - enum Terms { // First 8 entries are for PieceType - MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERMS_NB - }; + // Evaluation weights, indexed by the corresponding evaluation term + enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety }; - Score scores[COLOR_NB][TERMS_NB]; - EvalInfo ei; - ScaleFactor sf; + const struct Weight { int mg, eg; } Weights[] = { + {289, 344}, {233, 201}, {221, 273}, {46, 0}, {322, 0} + }; - double to_cp(Value v); - void write(int idx, Color c, Score s); - void write(int idx, Score w, Score b = SCORE_ZERO); - void print(std::stringstream& ss, const char* name, int idx); - std::string do_trace(const Position& pos); + Score operator*(Score s, const Weight& w) { + return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); } - // Evaluation weights, indexed by evaluation term - enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety }; - const struct Weight { int mg, eg; } Weights[] = { - {289, 344}, {233, 201}, {221, 273}, {46, 0}, {318, 0} - }; - typedef Value V; + #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) // MobilityBonus[PieceType][attacked] contains bonuses for middle and end @@ -103,66 +109,64 @@ namespace { // friendly pieces. const Score MobilityBonus[][32] = { {}, {}, - { S(-65,-50), S(-42,-30), S(-9,-10), S( 3, 0), S(15, 10), S(27, 20), // Knights - S( 37, 28), S( 42, 31), S(44, 33) }, - { S(-52,-47), S(-28,-23), S( 6, 1), S(20, 15), S(34, 29), S(48, 43), // Bishops - S( 60, 55), S( 68, 63), S(74, 68), S(77, 72), S(80, 75), S(82, 77), - S( 84, 79), S( 86, 81) }, - { S(-47,-53), S(-31,-26), S(-5, 0), S( 1, 16), S( 7, 32), S(13, 48), // Rooks - S( 18, 64), S( 22, 80), S(26, 96), S(29,109), S(31,115), S(33,119), - S( 35,122), S( 36,123), S(37,124) }, - { S(-42,-40), S(-28,-23), S(-5, -7), S( 0, 0), S( 6, 10), S(11, 19), // Queens - S( 13, 29), S( 18, 38), S(20, 40), S(21, 41), S(22, 41), S(22, 41), - S( 22, 41), S( 23, 41), S(24, 41), S(25, 41), S(25, 41), S(25, 41), - S( 25, 41), S( 25, 41), S(25, 41), S(25, 41), S(25, 41), S(25, 41), - S( 25, 41), S( 25, 41), S(25, 41), S(25, 41) } + { S(-68,-49), S(-46,-33), S(-3,-12), S( 5, -4), S( 9, 11), S(15, 16), // Knights + S( 23, 27), S( 33, 28), S(37, 29) }, + { S(-49,-44), S(-23,-16), S(16, 1), S(29, 16), S(40, 25), S(51, 34), // Bishops + S( 55, 43), S( 61, 49), S(64, 51), S(68, 52), S(73, 55), S(75, 60), + S( 80, 65), S( 86, 66) }, + { S(-50,-57), S(-28,-22), S(-11, 7), S(-1, 29), S( 0, 39), S( 1, 46), // Rooks + S( 10, 66), S( 16, 79), S(22, 86), S(23,103), S(30,109), S(33,111), + S( 37,115), S( 38,119), S(48,124) }, + { S(-43,-30), S(-27,-15), S( 1, -5), S( 2, -3), S(14, 10), S(18, 24), // Queens + S( 20, 27), S( 33, 37), S(33, 38), S(34, 43), S(40, 46), S(43, 56), + S( 46, 61), S( 52, 63), S(52, 63), S(57, 65), S(60, 70), S(61, 74), + S( 67, 80), S( 76, 82), S(77, 88), S(82, 94), S(86, 95), S(90, 96), + S( 94, 99), S( 96,100), S(99,111), S(99,112) } }; - // Outpost[PieceType][Square] contains bonuses for knights and bishops outposts, - // indexed by piece type and square (from white's point of view). - const Value Outpost[][SQUARE_NB] = { - {// A B C D E F G H - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), - V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), - V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), - V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), - V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0) }, - { - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Bishops - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), - V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), - V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), - V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), - V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) } + // 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(28, 7), S(42,11) }, // Knights + { S(12, 3), S(18, 5) } // Bishops }; - // Threat[attacking][attacked] contains bonuses according to which piece - // type attacks which one. - const Score Threat[][PIECE_TYPE_NB] = { - { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) }, // Protected Minor attacks - { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) }, // Protected Major attacks - { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) }, // Weak Minor attacks - { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } // Weak Major attacks + // Threat[defended/weak][minor/major attacking][attacked PieceType] contains + // bonuses according to which piece type attacks which one. + const Score Threat[][2][PIECE_TYPE_NB] = { + { { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) }, // Defended Minor + { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Defended Major + { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) }, // Weak Minor + { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } } // Weak Major }; // ThreatenedByPawn[PieceType] contains a penalty according to which piece // type is attacked by an enemy pawn. - const Score ThreatenedByPawn[] = { - S(0, 0), S(0, 0), S(87, 118), S(84, 122), S(114, 203), S(121, 217) + const Score ThreatenedByPawn[PIECE_TYPE_NB] = { + S(0, 0), S(0, 0), S(107, 138), S(84, 122), S(114, 203), S(121, 217) + }; + + // Passed[mg/eg][rank] contains midgame and endgame bonuses for passed pawns. + // We don't use a Score because we process the two components independently. + const Value Passed[][RANK_NB] = { + { V(0), V( 1), V(34), V(90), V(214), V(328) }, + { V(7), V(14), V(37), V(63), V(134), V(189) } }; + const Score ThreatenedByHangingPawn = S(40, 60); + // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S(2 , 58); - const Score KingOnMany = S(6 ,125); - const Score RookOnPawn = S(7 , 27); - const Score RookOpenFile = S(43, 21); - const Score RookSemiOpenFile = S(19, 10); - const Score BishopPawns = S( 8, 12); - const Score MinorBehindPawn = S(16, 0); - const Score TrappedRook = S(92, 0); - const Score Unstoppable = S( 0, 20); - const Score Hanging = S(31, 26); + const Score KingOnOne = S( 2, 58); + const Score KingOnMany = S( 6,125); + const Score RookOnPawn = S( 7, 27); + const Score RookOnOpenFile = S(43, 21); + const Score RookOnSemiOpenFile = S(19, 10); + const Score BishopPawns = S( 8, 12); + const Score MinorBehindPawn = S(16, 0); + const Score TrappedRook = S(92, 0); + const Score Unstoppable = S( 0, 20); + const Score Hanging = S(31, 26); + const Score PawnAttackThreat = S(20, 20); // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only @@ -170,40 +174,33 @@ namespace { const Score TrappedBishopA1H1 = S(50, 50); #undef S + #undef V // SpaceMask[Color] contains the area of the board which is considered // by the space evaluation. In the middlegame, each side is given a bonus // based on how many squares inside this area are safe and available for // friendly minor pieces. - const Bitboard SpaceMask[] = { + const Bitboard SpaceMask[COLOR_NB] = { (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank2BB | Rank3BB | Rank4BB), (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank7BB | Rank6BB | Rank5BB) }; - // King danger constants and variables. The king danger scores are taken - // from KingDanger[]. Various little "meta-bonuses" measuring the strength + // 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[] = { 0, 0, 2, 2, 3, 5 }; - - // Bonuses for enemy's safe checks - const int QueenContactCheck = 24; - const int RookContactCheck = 16; - const int QueenCheck = 12; - const int RookCheck = 8; - const int BishopCheck = 2; - const int KnightCheck = 3; - - // KingDanger[attackUnits] contains the actual king danger weighted - // scores, indexed by a calculated integer number. - Score KingDanger[128]; - - // apply_weight() weighs score 'v' by weight 'w' trying to prevent overflow - Score apply_weight(Score v, const Weight& w) { - return make_score(mg_value(v) * w.mg / 256, eg_value(v) * w.eg / 256); - } + const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 7, 5, 4, 1 }; + + // Penalties for enemy's safe checks + const int QueenContactCheck = 89; + const int RookContactCheck = 71; + const int QueenCheck = 50; + const int RookCheck = 37; + const int BishopCheck = 6; + const int KnightCheck = 14; // init_eval_info() initializes king bitboards for given color adding @@ -212,13 +209,12 @@ namespace { template void init_eval_info(const Position& pos, EvalInfo& ei) { - const Color Them = (Us == WHITE ? BLACK : WHITE); + const Color Them = (Us == WHITE ? BLACK : WHITE); 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.king_square(Them)); ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); + Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.square(Them)); // Init king safety tables only if we are going to use them if (pos.non_pawn_material(Us) >= QueenValueMg) @@ -233,33 +229,6 @@ namespace { } - // evaluate_outpost() evaluates bishop and knight outpost squares - - template - Score evaluate_outpost(const Position& pos, const EvalInfo& ei, Square s) { - - const Color Them = (Us == WHITE ? BLACK : WHITE); - - assert (Pt == BISHOP || Pt == KNIGHT); - - // Initial bonus based on square - Value bonus = Outpost[Pt == BISHOP][relative_square(Us, s)]; - - // Increase bonus if supported by pawn, especially if the opponent has - // no minor piece which can trade with the outpost piece. - if (bonus && (ei.attackedBy[Us][PAWN] & s)) - { - if ( !pos.pieces(Them, KNIGHT) - && !(squares_of_color(s) & pos.pieces(Them, BISHOP))) - bonus += bonus + bonus / 2; - else - bonus += bonus / 2; - } - - return make_score(bonus * 2, bonus / 2); - } - - // evaluate_pieces() assigns bonuses and penalties to the pieces of a given color template @@ -271,7 +240,7 @@ namespace { const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square* pl = pos.list(Us); + const Square* pl = pos.squares(Us); ei.attackedBy[Us][Pt] = 0; @@ -283,7 +252,7 @@ namespace { : pos.attacks_from(s); if (ei.pinnedPieces[Us] & s) - b &= LineBB[pos.king_square(Us)][s]; + b &= LineBB[pos.square(Us)][s]; ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; @@ -301,77 +270,72 @@ namespace { | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); - int mob = Pt != QUEEN ? popcount(b & mobilityArea[Us]) - : popcount(b & mobilityArea[Us]); + int mob = popcount(b & mobilityArea[Us]); mobility[Us] += MobilityBonus[Pt][mob]; - // Decrease score if we are attacked by an enemy pawn. The remaining part - // of threat evaluation must be done later when we have full attack info. - if (ei.attackedBy[Them][PAWN] & s) - score -= ThreatenedByPawn[Pt]; - if (Pt == BISHOP || Pt == KNIGHT) { - // Penalty for bishop with same colored pawns - if (Pt == BISHOP) - score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); - - // Bishop and knight outpost square - if (!(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) - score += evaluate_outpost(pos, ei, s); + // Bonus for outpost square + if ( relative_rank(Us, s) >= RANK_4 + && !(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) + score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)]; - // Bishop or knight behind a pawn + // Bonus when behind a pawn if ( relative_rank(Us, s) < RANK_5 && (pos.pieces(PAWN) & (s + pawn_push(Us)))) score += MinorBehindPawn; + + // Penalty for pawns on same color square of bishop + if (Pt == BISHOP) + score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); + + // An important Chess960 pattern: A cornered bishop blocked by a friendly + // pawn diagonally in front of it is a very serious problem, especially + // when that pawn is also blocked. + if ( Pt == BISHOP + && pos.is_chess960() + && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) + { + Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); + if (pos.piece_on(s + d) == make_piece(Us, PAWN)) + score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 + : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 + : TrappedBishopA1H1; + } } if (Pt == ROOK) { - // Rook piece attacking enemy pawns on the same rank/file + // Bonus for aligning with enemy pawns on the same rank/file if (relative_rank(Us, s) >= RANK_5) { - Bitboard pawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; - if (pawns) - score += popcount(pawns) * RookOnPawn; + Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; + if (alignedPawns) + score += popcount(alignedPawns) * RookOnPawn; } - // Give a bonus for a rook on a open or semi-open file + // Bonus when on an open or semi-open file if (ei.pi->semiopen_file(Us, file_of(s))) - score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOpenFile : RookSemiOpenFile; - - if (mob > 3 || ei.pi->semiopen_file(Us, file_of(s))) - continue; + score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOnOpenFile : RookOnSemiOpenFile; - Square ksq = pos.king_square(Us); - - // Penalize rooks which are trapped by a king. Penalize more if the - // king has lost its castling capability. - if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) - && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) - && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) - score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); - } + // Penalize when trapped by the king, even more if king cannot castle + if (mob <= 3 && !ei.pi->semiopen_file(Us, file_of(s))) + { + Square ksq = pos.square(Us); - // An important Chess960 pattern: A cornered bishop blocked by a friendly - // pawn diagonally in front of it is a very serious problem, especially - // when that pawn is also blocked. - if ( Pt == BISHOP - && pos.is_chess960() - && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) - { - Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); - if (pos.piece_on(s + d) == make_piece(Us, PAWN)) - score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 - : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 - : TrappedBishopA1H1; + if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) + && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) + && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us)); + } } } if (Trace) Tracing::write(Pt, Us, score); + // Recursively call evaluate_pieces() of next piece type until KING excluded return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } @@ -390,7 +354,7 @@ namespace { Bitboard undefended, b, b1, b2, safe; int attackUnits; - const Square ksq = pos.king_square(Us); + const Square ksq = pos.square(Us); // King shelter and enemy pawns storm Score score = ei.pi->king_safety(pos, ksq); @@ -407,33 +371,32 @@ namespace { | ei.attackedBy[Us][QUEEN]); // Initialize the 'attackUnits' variable, which is used later on as an - // index to the KingDanger[] array. The initial value is based on the + // index into the KingDanger[] array. 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(20, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) - + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount(undefended)) - + 2 * (ei.pinnedPieces[Us] != 0) - - mg_value(score) / 32 - - !pos.count(Them) * 15; + attackUnits = std::min(74, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) + + 8 * ei.kingAdjacentZoneAttacksCount[Them] + + 25 * popcount(undefended) + + 11 * (ei.pinnedPieces[Us] != 0) + - mg_value(score) / 8 + - !pos.count(Them) * 60; // Analyse the enemy's safe queen contact checks. Firstly, find the - // undefended squares around the king that are attacked by the enemy's - // queen... + // 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]); + b &= ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]; if (b) - attackUnits += QueenContactCheck * popcount(b); + attackUnits += QueenContactCheck * popcount(b); } // Analyse the enemy's safe rook contact checks. Firstly, find the - // undefended squares around the king that are attacked by the enemy's - // rooks... + // undefended squares around the king reachable by the enemy rooks... b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces(Them); // Consider only squares where the enemy's rook gives check @@ -443,16 +406,16 @@ namespace { { // ...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][QUEEN]); + | ei.attackedBy[Them][BISHOP]); if (b) - attackUnits += RookContactCheck * popcount(b); + attackUnits += RookContactCheck * popcount(b); } // Analyse the enemy's safe distance checks for sliders and knights - safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]); + safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - b1 = pos.attacks_from(ksq) & safe; + b1 = pos.attacks_from(ksq) & safe; b2 = pos.attacks_from(ksq) & safe; // Enemy queen safe checks @@ -475,12 +438,9 @@ namespace { if (b) attackUnits += KnightCheck * popcount(b); - // To index KingDanger[] attackUnits must be in [0, 99] range - attackUnits = std::min(99, std::max(0, attackUnits)); - // Finally, extract the king danger score from the KingDanger[] // array and subtract the score from evaluation. - score -= KingDanger[attackUnits]; + score -= KingDanger[std::max(std::min(attackUnits, 399), 0)]; } if (Trace) @@ -490,63 +450,97 @@ namespace { } - - // evaluate_threats() assigns bonuses according to the type of attacking piece // and the type of attacked one. template Score evaluate_threats(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); + const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE); + const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW); + const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); + const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); + + enum { Defended, Weak }; + enum { Minor, Major }; - enum { Protected_Minor, Protected_Major, Minor, Major }; - Bitboard b, weakEnemies, protectedEnemies; + Bitboard b, weak, defended, safeThreats; Score score = SCORE_ZERO; - // Enemies defended by a pawn and under our attack - protectedEnemies = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) - & ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]); + // Non-pawn enemies attacked by a pawn + weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN]; + + if (weak) + { + b = pos.pieces(Us, PAWN) & ( ~ei.attackedBy[Them][ALL_PIECES] + | ei.attackedBy[Us][ALL_PIECES]); + + safeThreats = (shift_bb(b) | shift_bb(b)) & weak; + + if (weak ^ safeThreats) + score += ThreatenedByHangingPawn; + + while (safeThreats) + score += ThreatenedByPawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; + } + + // Non-pawn enemies defended by a pawn + defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Them][PAWN]; - if (protectedEnemies) + // Add a bonus according to the kind of attacking pieces + if (defended) { - // Enemies defended by a pawn and under our attack by a minor piece - b = protectedEnemies & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + b = defended & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); while (b) - score += Threat[Protected_Minor][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Defended][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - // Enemies defended by a pawn and under our attack by a ROOK - b = protectedEnemies & (ei.attackedBy[Us][ROOK]); + b = defended & (ei.attackedBy[Us][ROOK]); while (b) - score += Threat[Protected_Major][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Defended][Major][type_of(pos.piece_on(pop_lsb(&b)))]; } // Enemies not defended by a pawn and under our attack - weakEnemies = pos.pieces(Them) - & ~ei.attackedBy[Them][PAWN] - & ei.attackedBy[Us][ALL_PIECES]; + weak = pos.pieces(Them) + & ~ei.attackedBy[Them][PAWN] + & ei.attackedBy[Us][ALL_PIECES]; - // Add a bonus according if the attacking pieces are minor or major - if (weakEnemies) + // Add a bonus according to the kind of attacking pieces + if (weak) { - b = weakEnemies & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + b = weak & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); while (b) - score += Threat[Minor][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Weak][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); + b = weak & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); while (b) - score += Threat[Major][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Weak][Major][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & ~ei.attackedBy[Them][ALL_PIECES]; + b = weak & ~ei.attackedBy[Them][ALL_PIECES]; if (b) - score += more_than_one(b) ? Hanging * popcount(b) : Hanging; + score += Hanging * popcount(b); - b = weakEnemies & ei.attackedBy[Us][KING]; + b = weak & ei.attackedBy[Us][KING]; if (b) score += more_than_one(b) ? KingOnMany : KingOnOne; } + // Bonus if some pawns can safely push and attack an enemy piece + b = pos.pieces(Us, PAWN) & ~TRank7BB; + b = shift_bb(b | (shift_bb(b & TRank2BB) & ~pos.pieces())); + + b &= ~pos.pieces() + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); + + b = (shift_bb(b) | shift_bb(b)) + & pos.pieces(Them) + & ~ei.attackedBy[Us][PAWN]; + + if (b) + score += popcount(b) * PawnAttackThreat; + if (Trace) Tracing::write(Tracing::THREAT, Us, score); @@ -575,20 +569,19 @@ namespace { int r = relative_rank(Us, s) - RANK_2; int rr = r * (r - 1); - // Base bonus based on rank - Value mbonus = Value(17 * rr), ebonus = Value(7 * (rr + r + 1)); + Value mbonus = Passed[MG][r], ebonus = Passed[EG][r]; if (rr) { Square blockSq = s + pawn_push(Us); // Adjust bonus based on the king's proximity - ebonus += distance(pos.king_square(Them), blockSq) * 5 * rr - - distance(pos.king_square(Us ), blockSq) * 2 * rr; + ebonus += distance(pos.square(Them), blockSq) * 5 * rr + - distance(pos.square(Us ), blockSq) * 2 * rr; // If blockSq is not the queening square then consider also a second push if (relative_rank(Us, blockSq) != RANK_8) - ebonus -= distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr; + ebonus -= distance(pos.square(Us), blockSq + pawn_push(Us)) * rr; // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -631,22 +624,10 @@ namespace { } if (Trace) - Tracing::write(Tracing::PASSED, Us, apply_weight(score, Weights[PassedPawns])); + Tracing::write(Tracing::PASSED, Us, score * Weights[PassedPawns]); // Add the scores to the middlegame and endgame eval - return apply_weight(score, Weights[PassedPawns]); - } - - - // evaluate_unstoppable_pawns() scores the most advanced passed pawn. In case - // both players have no pieces but pawns, this is somewhat related to the - // possibility that pawns are unstoppable. - - Score evaluate_unstoppable_pawns(Color us, const EvalInfo& ei) { - - Bitboard b = ei.pi->passed_pawns(us); - - return b ? Unstoppable * int(relative_rank(us, frontmost_sq(us, b))) : SCORE_ZERO; + return score * Weights[PassedPawns]; } @@ -654,10 +635,10 @@ namespace { // space evaluation is a simple bonus based on the number of safe squares // available for minor pieces on the central four files on ranks 2--4. Safe // squares one, two or three squares behind a friendly pawn are counted - // twice. Finally, the space bonus is scaled by a weight taken from the - // material hash table. The aim is to improve play on game opening. + // twice. Finally, the space bonus is multiplied by a weight. The aim is to + // improve play on game opening. template - int evaluate_space(const Position& pos, const EvalInfo& ei) { + Score evaluate_space(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); @@ -678,7 +659,11 @@ namespace { assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); // Count safe + (behind & safe) with a single popcount - return 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); + + return make_score(bonus * weight * weight, 0); } @@ -691,7 +676,6 @@ namespace { EvalInfo ei; Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; - Thread* thisThread = pos.this_thread(); // Initialize score by reading the incrementally updated scores included // in the position object (material + piece square tables). @@ -699,17 +683,17 @@ namespace { score = pos.psq_score(); // Probe the material hash table - ei.mi = Material::probe(pos, thisThread->materialTable, thisThread->endgames); - score += ei.mi->material_value(); + ei.mi = Material::probe(pos); + score += ei.mi->imbalance(); // If we have a specialized evaluation function for the current material // configuration, call it and return. if (ei.mi->specialized_eval_exists()) - return ei.mi->evaluate(pos) + Eval::Tempo; + return ei.mi->evaluate(pos); // Probe the pawn hash table - ei.pi = Pawns::probe(pos, thisThread->pawnsTable); - score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); + ei.pi = Pawns::probe(pos); + score += ei.pi->pawns_score() * Weights[PawnStructure]; // Initialize attack and king safety bitboards init_eval_info(pos, ei); @@ -718,13 +702,22 @@ namespace { ei.attackedBy[WHITE][ALL_PIECES] |= ei.attackedBy[WHITE][KING]; ei.attackedBy[BLACK][ALL_PIECES] |= ei.attackedBy[BLACK][KING]; - // Do not include in mobility squares protected by enemy pawns or occupied by our pawns or king - Bitboard mobilityArea[] = { ~(ei.attackedBy[BLACK][PAWN] | pos.pieces(WHITE, PAWN, KING)), - ~(ei.attackedBy[WHITE][PAWN] | pos.pieces(BLACK, PAWN, KING)) }; + // Pawns blocked or on ranks 2 and 3. Will be excluded from the mobility area + Bitboard blockedPawns[] = { + pos.pieces(WHITE, PAWN) & (shift_bb(pos.pieces()) | Rank2BB | Rank3BB), + pos.pieces(BLACK, PAWN) & (shift_bb(pos.pieces()) | Rank7BB | Rank6BB) + }; + + // Do not include in mobility squares protected by enemy pawns, or occupied + // by our blocked pawns or king. + Bitboard mobilityArea[] = { + ~(ei.attackedBy[BLACK][PAWN] | blockedPawns[WHITE] | pos.square(WHITE)), + ~(ei.attackedBy[WHITE][PAWN] | blockedPawns[BLACK] | pos.square(BLACK)) + }; // Evaluate pieces and mobility score += evaluate_pieces(pos, ei, mobility, mobilityArea); - score += apply_weight(mobility[WHITE] - mobility[BLACK], Weights[Mobility]); + score += (mobility[WHITE] - mobility[BLACK]) * Weights[Mobility]; // Evaluate kings after all other pieces because we need complete attack // information when computing the king safety evaluation. @@ -741,16 +734,19 @@ namespace { // If both sides have only pawns, score for potential unstoppable pawns if (!pos.non_pawn_material(WHITE) && !pos.non_pawn_material(BLACK)) - score += evaluate_unstoppable_pawns(WHITE, ei) - - evaluate_unstoppable_pawns(BLACK, ei); - - // Evaluate space for both sides, only in middlegame - if (ei.mi->space_weight()) { - int s = evaluate_space(pos, ei) - evaluate_space(pos, ei); - score += apply_weight(s * ei.mi->space_weight(), Weights[Space]); + Bitboard b; + if ((b = ei.pi->passed_pawns(WHITE)) != 0) + score += int(relative_rank(WHITE, frontmost_sq(WHITE, b))) * Unstoppable; + + if ((b = ei.pi->passed_pawns(BLACK)) != 0) + score -= int(relative_rank(BLACK, frontmost_sq(BLACK, b))) * Unstoppable; } + // Evaluate space for both sides, only during opening + if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 11756) + score += (evaluate_space(pos, ei) - evaluate_space(pos, ei)) * Weights[Space]; + // Scale winning side if position is more drawish than it appears Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK; ScaleFactor sf = ei.mi->scale_factor(pos, strongSide); @@ -777,7 +773,7 @@ namespace { // pawns are drawish. else if ( abs(eg_value(score)) <= BishopValueEg && ei.pi->pawn_span(strongSide) <= 1 - && !pos.pawn_passed(~strongSide, pos.king_square(~strongSide))) + && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(56) : ScaleFactor(38); } @@ -787,58 +783,48 @@ namespace { v /= int(PHASE_MIDGAME); - // In case of tracing add all single evaluation contributions for both white and black + // In case of tracing add all single evaluation terms for both white and black if (Trace) { Tracing::write(Tracing::MATERIAL, pos.psq_score()); - Tracing::write(Tracing::IMBALANCE, ei.mi->material_value()); - Tracing::write(PAWN, ei.pi->pawns_value()); - Tracing::write(Tracing::MOBILITY, apply_weight(mobility[WHITE], Weights[Mobility]) - , apply_weight(mobility[BLACK], Weights[Mobility])); - Score w = ei.mi->space_weight() * evaluate_space(pos, ei); - Score b = ei.mi->space_weight() * evaluate_space(pos, ei); - Tracing::write(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); + Tracing::write(Tracing::IMBALANCE, ei.mi->imbalance()); + Tracing::write(PAWN, ei.pi->pawns_score()); + Tracing::write(Tracing::MOBILITY, mobility[WHITE] * Weights[Mobility] + , mobility[BLACK] * Weights[Mobility]); + Tracing::write(Tracing::SPACE, evaluate_space(pos, ei) * Weights[Space] + , evaluate_space(pos, ei) * Weights[Space]); Tracing::write(Tracing::TOTAL, score); - Tracing::ei = ei; - Tracing::sf = sf; } - return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; + return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; // Side to move point of view } - // Tracing function definitions + // Tracing functions double Tracing::to_cp(Value v) { return double(v) / PawnValueEg; } void Tracing::write(int idx, Color c, Score s) { scores[c][idx] = s; } void Tracing::write(int idx, Score w, Score b) { - - write(idx, WHITE, w); - write(idx, BLACK, b); + scores[WHITE][idx] = w, scores[BLACK][idx] = b; } - void Tracing::print(std::stringstream& ss, const char* name, int idx) { - - Score wScore = scores[WHITE][idx]; - Score bScore = scores[BLACK][idx]; - - switch (idx) { - case MATERIAL: case IMBALANCE: case PAWN: case TOTAL: - ss << std::setw(15) << name << " | --- --- | --- --- | " - << std::setw(5) << to_cp(mg_value(wScore - bScore)) << " " - << std::setw(5) << to_cp(eg_value(wScore - bScore)) << " \n"; - break; - default: - ss << std::setw(15) << name << " | " << std::noshowpos - << std::setw(5) << to_cp(mg_value(wScore)) << " " - << std::setw(5) << to_cp(eg_value(wScore)) << " | " - << std::setw(5) << to_cp(mg_value(bScore)) << " " - << std::setw(5) << to_cp(eg_value(bScore)) << " | " - << std::setw(5) << to_cp(mg_value(wScore - bScore)) << " " - << std::setw(5) << to_cp(eg_value(wScore - bScore)) << " \n"; - } + std::ostream& Tracing::operator<<(std::ostream& os, Term t) { + + double wScore[] = { to_cp(mg_value(scores[WHITE][t])), to_cp(eg_value(scores[WHITE][t])) }; + double bScore[] = { to_cp(mg_value(scores[BLACK][t])), to_cp(eg_value(scores[BLACK][t])) }; + + if (t == MATERIAL || t == IMBALANCE || t == Term(PAWN) || t == TOTAL) + os << " --- --- | --- --- | "; + else + os << std::setw(5) << wScore[MG] << " " << std::setw(5) << wScore[EG] << " | " + << std::setw(5) << bScore[MG] << " " << std::setw(5) << bScore[EG] << " | "; + + os << std::setw(5) << wScore[MG] - bScore[MG] << " " + << std::setw(5) << wScore[EG] - bScore[EG] << " \n"; + + return os; } std::string Tracing::do_trace(const Position& pos) { @@ -852,23 +838,21 @@ namespace { ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2) << " Eval term | White | Black | Total \n" << " | MG EG | MG EG | MG EG \n" - << "----------------+-------------+-------------+-------------\n"; - - print(ss, "Material", MATERIAL); - print(ss, "Imbalance", IMBALANCE); - print(ss, "Pawns", PAWN); - print(ss, "Knights", KNIGHT); - print(ss, "Bishops", BISHOP); - print(ss, "Rooks", ROOK); - print(ss, "Queens", QUEEN); - print(ss, "Mobility", MOBILITY); - print(ss, "King safety", KING); - print(ss, "Threats", THREAT); - print(ss, "Passed pawns", PASSED); - print(ss, "Space", SPACE); - - ss << "----------------+-------------+-------------+-------------\n"; - print(ss, "Total", TOTAL); + << "----------------+-------------+-------------+-------------\n" + << " Material | " << Term(MATERIAL) + << " Imbalance | " << Term(IMBALANCE) + << " Pawns | " << Term(PAWN) + << " Knights | " << Term(KNIGHT) + << " Bishop | " << Term(BISHOP) + << " Rooks | " << Term(ROOK) + << " Queens | " << Term(QUEEN) + << " Mobility | " << Term(MOBILITY) + << " King safety | " << Term(KING) + << " Threats | " << Term(THREAT) + << " Passed pawns | " << Term(PASSED) + << " Space | " << Term(SPACE) + << "----------------+-------------+-------------+-------------\n" + << " Total | " << Term(TOTAL); ss << "\nTotal Evaluation: " << to_cp(v) << " (white side)\n"; @@ -897,17 +881,18 @@ namespace Eval { } - /// init() computes evaluation weights. + /// init() computes evaluation weights, usually at startup void init() { - const double MaxSlope = 30; - const double Peak = 1280; + const int MaxSlope = 8700; + const int Peak = 1280000; + int t = 0; - for (int t = 0, i = 1; i < 100; ++i) + for (int i = 0; i < 400; ++i) { - t = int(std::min(Peak, std::min(0.4 * i * i, t + MaxSlope))); - KingDanger[i] = apply_weight(make_score(t, 0), Weights[KingSafety]); + t = std::min(Peak, std::min(i * i * 27, t + MaxSlope)); + KingDanger[i] = make_score(t / 1000, 0) * Weights[KingSafety]; } }