X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=bf90e08c0eeae5817ea427966f63fd74cb124d48;hp=383d9e62f1fec595399c722c8dc59baff9938e63;hb=ed72a1e9ba37a9fa2674da8f46bb0597a1721c2d;hpb=3e2591d83c285597a7400c79b61ab9dc38875163 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 383d9e62..bf90e08c 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -102,6 +102,7 @@ namespace { int kingAdjacentZoneAttacksCount[COLOR_NB]; Bitboard pinnedPieces[COLOR_NB]; + Material::Entry* me; Pawns::Entry* pi; }; @@ -110,7 +111,7 @@ namespace { enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety }; const struct Weight { int mg, eg; } Weights[] = { - {289, 344}, {233, 201}, {221, 273}, {46, 0}, {322, 0} + {266, 334}, {214, 203}, {193, 262}, {47, 0}, {330, 0} }; Score operator*(Score s, const Weight& w) { @@ -126,55 +127,68 @@ namespace { // friendly pieces. const Score MobilityBonus[][32] = { {}, {}, - { 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) } + { S(-70,-52), S(-52,-37), S( -7,-17), S( 0, -6), S( 8, 5), S( 16, 9), // Knights + S( 23, 20), S( 31, 21), S( 36, 22) }, + { S(-49,-44), S(-22,-13), S( 16, 0), S( 27, 11), S( 38, 19), S( 52, 34), // Bishops + S( 56, 44), S( 65, 47), S( 67, 51), S( 73, 56), S( 81, 59), S( 83, 69), + S( 95, 72), S(100, 75) }, + { S(-49,-57), S(-22,-14), S(-10, 18), S( -5, 39), S( -4, 50), S( -2, 58), // Rooks + S( 6, 78), S( 11, 86), S( 17, 92), S( 19,103), S( 26,111), S( 27,115), + S( 36,119), S( 41,121), S( 50,122) }, + { S(-41,-24), S(-26, -8), S( 0, 6), S( 2, 14), S( 12, 27), S( 21, 40), // Queens + S( 22, 45), S( 37, 55), S( 40, 57), S( 43, 63), S( 50, 68), S( 52, 74), + S( 56, 80), S( 66, 84), S( 68, 85), S( 69, 88), S( 71, 92), S( 72, 94), + S( 80, 96), S( 89, 98), S( 94,101), S(102,113), S(106,114), S(107,116), + S(112,125), S(113,127), S(117,137), S(122,143) } }; // 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 + { S(42,11), S(63,17) }, // Knights + { S(18, 5), S(27, 8) } // Bishops }; - // Threat[defended/weak][minor/major attacking][attacked PieceType] contains + // 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 + }; + + // Threat[minor/rook][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 + // Attacks on lesser pieces which are pawn defended are not considered. + const Score Threat[2][PIECE_TYPE_NB] = { + { S(0, 0), S(0, 33), S(45, 43), S(46, 47), S(72, 107), S(48,118) }, // Minor attacks + { S(0, 0), S(0, 25), S(40, 62), S(40, 59), S( 0, 34), S(35, 48) } // Rook attacks }; // ThreatenedByPawn[PieceType] contains a penalty according to which piece - // type is attacked by an enemy pawn. + // type is attacked by a pawn. const Score ThreatenedByPawn[PIECE_TYPE_NB] = { - S(0, 0), S(0, 0), S(107, 138), S(84, 122), S(114, 203), S(121, 217) + S(0, 0), S(0, 0), S(176, 139), S(131, 127), S(217, 218), S(203, 215) }; - // Passed[mg/eg][rank] contains midgame and endgame bonuses for passed pawns. + // 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); + // PassedFile[File] contains a bonus according to the file of a passed pawn. + const Score PassedFile[] = { + S( 12, 10), S( 3, 10), S( 1, -8), S(-27, -12), + S(-27, -12), S( 1, -8), S( 3, 10), S( 12, 10) + }; + + const Score ThreatenedByHangingPawn = S(70, 63); // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S( 2, 58); - const Score KingOnMany = S( 6,125); + const Score KingOnOne = S( 3, 62); + const Score KingOnMany = S( 9,138); const Score RookOnPawn = S( 7, 27); const Score RookOnOpenFile = S(43, 21); const Score RookOnSemiOpenFile = S(19, 10); @@ -182,8 +196,9 @@ namespace { 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); + const Score Hanging = S(48, 28); + const Score PawnAttackThreat = S(31, 19); + const Score Checked = 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 @@ -193,15 +208,6 @@ namespace { #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[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 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 @@ -213,18 +219,17 @@ namespace { // Penalties for enemy's safe checks const int QueenContactCheck = 89; - const int RookContactCheck = 71; const int QueenCheck = 50; - const int RookCheck = 37; + const int RookCheck = 45; const int BishopCheck = 6; const int KnightCheck = 14; - // init_eval_info() initializes king bitboards for given color adding - // pawn attacks. To be done at the beginning of the evaluation. + // eval_init() initializes king and attack bitboards for given color + // adding pawn attacks. To be done at the beginning of the evaluation. template - void init_eval_info(const Position& pos, EvalInfo& ei) { + void eval_init(const Position& pos, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); @@ -247,17 +252,20 @@ namespace { } - // evaluate_pieces() assigns bonuses and penalties to the pieces of a given color - - template - Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, const Bitboard* mobilityArea) { + // evaluate_pieces() assigns bonuses and penalties to the pieces of a given + // color and type. - Bitboard b; + template + Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, + const Bitboard* mobilityArea) { + Bitboard b, bb; Square s; Score score = SCORE_ZERO; const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB + : Rank5BB | Rank4BB | Rank3BB); const Square* pl = pos.squares(Us); ei.attackedBy[Us][Pt] = 0; @@ -278,7 +286,7 @@ namespace { { ei.kingAttackersCount[Us]++; ei.kingAttackersWeight[Us] += KingAttackWeights[Pt]; - Bitboard bb = b & ei.attackedBy[Them][KING]; + bb = b & ei.attackedBy[Them][KING]; if (bb) ei.kingAdjacentZoneAttacksCount[Us] += popcount(bb); } @@ -294,10 +302,16 @@ namespace { if (Pt == BISHOP || Pt == KNIGHT) { - // Bonus for outpost square - if ( relative_rank(Us, s) >= RANK_4 - && !(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) + // Bonus for outpost squares + bb = OutpostRanks & ~ei.pi->pawn_attacks_span(Them); + if (bb & s) score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)]; + else + { + bb &= b & ~pos.pieces(Us); + if (bb) + score += ReachableOutpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & bb)]; + } // Bonus when behind a pawn if ( relative_rank(Us, s) < RANK_5 @@ -354,13 +368,13 @@ namespace { Trace::add(Pt, Us, score); // Recursively call evaluate_pieces() of next piece type until KING excluded - return score - evaluate_pieces(pos, ei, mobility, mobilityArea); + return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } + Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } + Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } // evaluate_king() assigns bonuses and penalties to a king of a given color @@ -381,7 +395,7 @@ namespace { if (ei.kingAttackersCount[Them]) { // Find the attacked squares around the king which have no defenders - // apart from the king itself + // apart from the king itself. undefended = ei.attackedBy[Them][ALL_PIECES] & ei.attackedBy[Us][KING] & ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] @@ -393,11 +407,11 @@ namespace { // 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(74, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) - + 8 * ei.kingAdjacentZoneAttacksCount[Them] - + 25 * popcount(undefended) + attackUnits = std::min(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) + + 9 * ei.kingAdjacentZoneAttacksCount[Them] + + 27 * popcount(undefended) + 11 * !!ei.pinnedPieces[Us] - - 60 * !pos.count(Them) + - 64 * !pos.count(Them) - mg_value(score) / 8; // Analyse the enemy's safe queen contact checks. Firstly, find the @@ -407,29 +421,13 @@ 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][ROOK]; + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK] + | ei.attackedBy[Them][KING]; if (b) attackUnits += QueenContactCheck * popcount(b); } - // Analyse the enemy's safe rook contact checks. Firstly, find the - // 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 - b &= PseudoAttacks[ROOK][ksq]; - - 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]); - - if (b) - attackUnits += RookContactCheck * popcount(b); - } - // Analyse the enemy's safe distance checks for sliders and knights safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); @@ -439,22 +437,34 @@ namespace { // Enemy queen safe checks b = (b1 | b2) & ei.attackedBy[Them][QUEEN]; if (b) + { attackUnits += QueenCheck * popcount(b); + score -= Checked; + } // Enemy rooks safe checks b = b1 & ei.attackedBy[Them][ROOK]; if (b) + { attackUnits += RookCheck * popcount(b); + score -= Checked; + } // Enemy bishops safe checks b = b2 & ei.attackedBy[Them][BISHOP]; if (b) + { attackUnits += BishopCheck * popcount(b); + score -= Checked; + } // Enemy knights safe checks b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe; if (b) + { attackUnits += KnightCheck * popcount(b); + score -= Checked; + } // Finally, extract the king danger score from the KingDanger[] // array and subtract the score from evaluation. @@ -481,8 +491,7 @@ namespace { const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); - enum { Defended, Weak }; - enum { Minor, Major }; + enum { Minor, Rook }; Bitboard b, weak, defended, safeThreats; Score score = SCORE_ZERO; @@ -507,33 +516,21 @@ namespace { // Non-pawn enemies defended by a pawn defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Them][PAWN]; - // Add a bonus according to the kind of attacking pieces - if (defended) - { - b = defended & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); - while (b) - score += Threat[Defended][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - - b = defended & (ei.attackedBy[Us][ROOK]); - while (b) - score += Threat[Defended][Major][type_of(pos.piece_on(pop_lsb(&b)))]; - } - // Enemies not defended by a pawn and under our attack weak = pos.pieces(Them) & ~ei.attackedBy[Them][PAWN] & ei.attackedBy[Us][ALL_PIECES]; // Add a bonus according to the kind of attacking pieces - if (weak) + if (defended | weak) { - b = weak & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + b = (defended | weak) & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); while (b) - score += Threat[Weak][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weak & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); + b = (pos.pieces(Them, QUEEN) | weak) & ei.attackedBy[Us][ROOK]; while (b) - score += Threat[Weak][Major][type_of(pos.piece_on(pop_lsb(&b)))]; + score += Threat[Rook ][type_of(pos.piece_on(pop_lsb(&b)))]; b = weak & ~ei.attackedBy[Them][ALL_PIECES]; if (b) @@ -619,7 +616,7 @@ namespace { // If there aren't any enemy attacks, assign a big bonus. Otherwise // assign a smaller bonus if the block square isn't attacked. - int k = !unsafeSquares ? 15 : !(unsafeSquares & blockSq) ? 9 : 0; + int k = !unsafeSquares ? 18 : !(unsafeSquares & blockSq) ? 8 : 0; // If the path to queen is fully defended, assign a big bonus. // Otherwise assign a smaller bonus if the block square is defended. @@ -638,7 +635,7 @@ namespace { if (pos.count(Us) < pos.count(Them)) ebonus += ebonus / 4; - score += make_score(mbonus, ebonus); + score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; } if (DoTrace) @@ -659,11 +656,14 @@ namespace { Score evaluate_space(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); + const Bitboard SpaceMask = + Us == WHITE ? (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank2BB | Rank3BB | Rank4BB) + : (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank7BB | Rank6BB | Rank5BB); // Find the safe squares for our pieces inside the area defined by - // SpaceMask[]. A square is unsafe if it is attacked by an enemy + // SpaceMask. A square is unsafe if it is attacked by an enemy // pawn, or if it is undefended and attacked by an enemy piece. - Bitboard safe = SpaceMask[Us] + Bitboard safe = SpaceMask & ~pos.pieces(Us, PAWN) & ~ei.attackedBy[Them][PAWN] & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); @@ -684,11 +684,67 @@ namespace { return make_score(bonus * weight * weight, 0); } + + // evaluate_initiative() computes the initiative correction value for the + // position, i.e. second order bonus/malus based on the known attacking/defending + // status of the players. + Score evaluate_initiative(const Position& pos, int asymmetry, Value eg) { + + int kingDistance = distance(pos.square(WHITE), pos.square(BLACK)); + int pawns = pos.count(WHITE) + pos.count(BLACK); + + // Compute the initiative bonus for the attacking side + int initiative = 8 * (pawns + asymmetry + kingDistance - 15); + + // Now apply the bonus: note that we find the attacking side by extracting + // the sign of the endgame value, and that we carefully cap the bonus so + // that the endgame score will never be divided by more than two. + int value = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg / 2)); + + return make_score(0, value); + } + + + // evaluate_scale_factor() computes the scale factor for the winning side + ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Score score) { + + Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK; + ScaleFactor sf = ei.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 ( ei.me->game_phase() < PHASE_MIDGAME + && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) + { + if (pos.opposite_bishops()) + { + // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) + // is almost a draw, in case of KBP vs KB is even more a draw. + if ( pos.non_pawn_material(WHITE) == BishopValueMg + && pos.non_pawn_material(BLACK) == BishopValueMg) + sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(31) : ScaleFactor(9); + + // 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); + } + // Endings where weaker side can place his king in front of the opponent's + // pawns are drawish. + else if ( abs(eg_value(score)) <= BishopValueEg + && ei.pi->pawn_span(strongSide) <= 1 + && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) + sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37); + } + + return sf; + } + } // namespace /// evaluate() is the main evaluation function. It returns a static evaluation -/// of the position always from the point of view of the side to move. +/// of the position from the point of view of the side to move. template Value Eval::evaluate(const Position& pos) { @@ -698,19 +754,19 @@ Value Eval::evaluate(const Position& pos) { EvalInfo ei; Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; - // Initialize score by reading the incrementally updated scores included - // in the position object (material + piece square tables). - // Score is computed from the point of view of white. + // 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 - Material::Entry* me = Material::probe(pos); - score += me->imbalance(); + 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 (me->specialized_eval_exists()) - return me->evaluate(pos); + if (ei.me->specialized_eval_exists()) + return ei.me->evaluate(pos); // Probe the pawn hash table ei.pi = Pawns::probe(pos); @@ -718,27 +774,27 @@ Value Eval::evaluate(const Position& pos) { // Initialize attack and king safety bitboards ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; - init_eval_info(pos, ei); - init_eval_info(pos, ei); + eval_init(pos, ei); + eval_init(pos, ei); - // Pawns blocked or on ranks 2 and 3. Will be excluded from the mobility area + // 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 + // Do not include in mobility area 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); + // Evaluate all pieces but king and pawns + score += evaluate_pieces(pos, ei, mobility, mobilityArea); score += (mobility[WHITE] - mobility[BLACK]) * Weights[Mobility]; - // Evaluate kings after all other pieces because we need complete attack + // Evaluate kings after all other pieces because we need full attack // information when computing the king safety evaluation. score += evaluate_king(pos, ei) - evaluate_king(pos, ei); @@ -763,50 +819,27 @@ Value Eval::evaluate(const Position& pos) { } // 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]; + if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222) + 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 = me->scale_factor(pos, strongSide); + // Evaluate position potential for the winning side + score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score)); - // If we don't already have an unusual scale factor, check for certain - // types of endgames, and use a lower scale for those. - if ( me->game_phase() < PHASE_MIDGAME - && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) - { - if (pos.opposite_bishops()) - { - // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) - // is almost a draw, in case of KBP vs KB is even more a draw. - if ( pos.non_pawn_material(WHITE) == BishopValueMg - && pos.non_pawn_material(BLACK) == BishopValueMg) - sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(32) : ScaleFactor(8); - - // 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(50 * sf / SCALE_FACTOR_NORMAL); - } - // Endings where weaker side can place his king in front of the opponent's - // pawns are drawish. - else if ( abs(eg_value(score)) <= BishopValueEg - && ei.pi->pawn_span(strongSide) <= 1 - && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) - sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(56) : ScaleFactor(38); - } + // Evaluate scale factor for the winning side + ScaleFactor sf = evaluate_scale_factor(pos, ei, score); // Interpolate between a middlegame and a (scaled by 'sf') endgame score - Value v = mg_value(score) * int(me->game_phase()) - + eg_value(score) * int(PHASE_MIDGAME - me->game_phase()) * sf / SCALE_FACTOR_NORMAL; + Value v = mg_value(score) * int(ei.me->game_phase()) + + eg_value(score) * int(PHASE_MIDGAME - ei.me->game_phase()) * sf / SCALE_FACTOR_NORMAL; v /= int(PHASE_MIDGAME); - // In case of tracing add all single evaluation terms + // In case of tracing add all remaining individual evaluation terms if (DoTrace) { Trace::add(MATERIAL, pos.psq_score()); - Trace::add(IMBALANCE, me->imbalance()); + Trace::add(IMBALANCE, ei.me->imbalance()); Trace::add(PAWN, ei.pi->pawns_score()); Trace::add(MOBILITY, mobility[WHITE] * Weights[Mobility] , mobility[BLACK] * Weights[Mobility]);