X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=897fc778a467ded318fbbba61f0dc047af32845a;hp=0554f490227b51e4b60ddacb1cee315bf03c174c;hb=55758344d3ccf49353bcd8f3a06a4553ff1b753a;hpb=55b46ffa909cf3873e4ac7129e324ed3eb1d0124 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 0554f490..897fc778 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -126,19 +126,19 @@ 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 @@ -148,17 +148,16 @@ namespace { { S(18, 5), S(27, 8) } // Bishops }; - // Threat[defended/weak][minor/rook attacking][attacked PieceType] contains + // 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) }, // Minor on Defended - { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Rook on Defended - { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) }, // Minor on Weak - { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } } // Rook on Weak + // Attacks on lesser pieces which are pawn defended are not considered. + const Score Threat[2][PIECE_TYPE_NB] = { + { S(0, 0), S(0, 32), S(25, 39), S(28, 44), S(42, 98), S(35,105) }, // Minor attacks + { S(0, 0), S(0, 27), S(26, 57), S(26, 57), S( 0, 30), S(23, 51) } // 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) }; @@ -172,8 +171,8 @@ namespace { // PassedFile[File] contains a bonus according to the file of a passed pawn. const Score PassedFile[] = { - S( 14, 13), S( 2, 5), S(-3, -4), S(-19, -14), - S(-19, -14), S(-3, -4), S( 2, 5), S( 14, 13) + 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(40, 60); @@ -414,7 +413,8 @@ 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); @@ -483,7 +483,6 @@ namespace { const Bitboard TRank2BB = (Us == WHITE ? Rank2BB : Rank7BB); const Bitboard TRank7BB = (Us == WHITE ? Rank7BB : Rank2BB); - enum { Defended, Weak }; enum { Minor, Rook }; Bitboard b, weak, defended, safeThreats; @@ -509,33 +508,21 @@ 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][Rook][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]; + b = (pos.pieces(Them, QUEEN) | weak) & ei.attackedBy[Us][ROOK]; while (b) - score += Threat[Weak][Rook][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) @@ -686,6 +673,28 @@ 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, const EvalInfo& ei, const Score positional_score) { + + int king_separation = distance(pos.square(WHITE), pos.square(BLACK)); + int pawns = pos.count(WHITE) + pos.count(BLACK); + int asymmetry = ei.pi->pawn_asymmetry(); + + // Compute the initiative bonus for the attacking side + int attacker_bonus = 8 * (pawns + asymmetry + king_separation) - 120; + + // Now apply the bonus: note that we find the attacking side by extracting the sign + // of the endgame value of "positional_score", and that we carefully cap the bonus so + // that the endgame score with the correction will never be divided by more than two. + int eg = eg_value(positional_score); + int value = ((eg > 0) - (eg < 0)) * std::max(attacker_bonus, -abs(eg / 2)); + + return make_score(0, value); + } + } // namespace @@ -768,6 +777,9 @@ Value Eval::evaluate(const Position& pos) { if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222) score += (evaluate_space(pos, ei) - evaluate_space(pos, ei)) * Weights[Space]; + // Evaluate initiative + score += evaluate_initiative(pos, ei, score); + // 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); @@ -798,11 +810,6 @@ Value Eval::evaluate(const Position& pos) { sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37); } - // Scale endgame by number of pawns - int p = pos.count(WHITE) + pos.count(BLACK); - int v_eg = 1 + abs(int(eg_value(score))); - sf = ScaleFactor(std::max(sf / 2, sf - 8 * SCALE_FACTOR_NORMAL * (12 - p) / v_eg)); - // 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;