X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=e84cf44ecba19151c58e9c8e71a041928e5a561c;hp=a5868f504b0b827af8e7320b780f57e6a2c2f656;hb=4626ec2890b140829e9971658ca948005b945fd4;hpb=fa0bffeafaa3554cb914249b4d032526e543359a diff --git a/src/evaluate.cpp b/src/evaluate.cpp index a5868f50..e84cf44e 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -207,8 +207,8 @@ namespace { ((1ULL << SQ_A8) | (1ULL << SQ_H8)) }; - // The SpaceMask[color] contains area of the board which is consdered by - // the space evaluation. In the middle game, each side is given a bonus + // The SpaceMask[color] contains the area of the board which is considered + // by the space evaluation. In the middle game, 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[2] = { @@ -241,6 +241,40 @@ namespace { // Bonus for having a mate threat, initialized from UCI options int MateThreatBonus; + // ThreatBonus[][] contains bonus according to which piece type + // attacks which one. + const Value MidgameThreatBonus[8][8] = { + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0),V(18), V(0),V(37), V(55), V(55), V(0), V(0) }, // KNIGHT attacks + { V(0),V(18),V(37), V(0), V(55), V(55), V(0), V(0) }, // BISHOP attacks + { V(0), V(9),V(27),V(27), V(0), V(37), V(0), V(0) }, // ROOK attacks + { V(0),V(27),V(27),V(27), V(27), V(0), V(0), V(0) }, // QUEEN attacks + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) } // not used + }; + + const Value EndgameThreatBonus[8][8] = { + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0),V(37), V(0),V(47), V(97), V(97), V(0), V(0) }, // KNIGHT attacks + { V(0),V(37),V(47), V(0), V(97), V(97), V(0), V(0) }, // BISHOP attacks + { V(0),V(27),V(47),V(47), V(0), V(47), V(0), V(0) }, // ROOK attacks + { V(0),V(37),V(37),V(37), V(37), V(0), V(0), V(0) }, // QUEEN attacks + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) }, // not used + { V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) } // not used + }; + + // ThreatedByPawnPenalty[] contains a penalty according to which piece + // type is attacked by an enemy pawn. + const Value MidgameThreatedByPawnPenalty[8] = { + V(0), V(0), V(56), V(56), V(76), V(86), V(0), V(0) + }; + + const Value EndgameThreatedByPawnPenalty[8] = { + V(0), V(0), V(70), V(70), V(99), V(118), V(0), V(0) + }; + // InitKingDanger[] contains bonuses based on the position of the defending // king. const int InitKingDanger[64] = { @@ -276,6 +310,9 @@ namespace { template void evaluate_king(const Position& pos, EvalInfo& ei); + template + void evaluate_threats(const Position& pos, EvalInfo& ei); + template void evaluate_space(const Position& pos, EvalInfo& ei); @@ -283,7 +320,8 @@ namespace { void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, EvalInfo& ei); void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei); inline Value apply_weight(Value v, int w); - Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]); + inline Score apply_weight(Score v, int wmg, int weg); + Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]); int weight_option(const std::string& opt, int weight); void init_safety(); } @@ -309,18 +347,17 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { assert(pos.is_ok()); assert(threadID >= 0 && threadID < THREAD_MAX); + assert(!pos.is_check()); memset(&ei, 0, sizeof(EvalInfo)); // Initialize by reading the incrementally updated scores included in the // position object (material + piece square tables) - ei.mgValue = pos.mg_value(); - ei.egValue = pos.eg_value(); + ei.value = pos.value(); // Probe the material hash table ei.mi = MaterialTable[threadID]->get_material_info(pos); - ei.mgValue += ei.mi->material_value(); - ei.egValue += ei.mi->material_value(); + ei.value += ei.mi->material_value(); // If we have a specialized evaluation function for the current material // configuration, call it and return @@ -334,8 +371,7 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // Probe the pawn hash table ei.pi = PawnTable[threadID]->get_pawn_info(pos); - ei.mgValue += apply_weight(ei.pi->mg_value(), WeightPawnStructureMidgame); - ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame); + ei.value += apply_weight(ei.pi->value(), WeightPawnStructureMidgame, WeightPawnStructureEndgame); // Initialize king attack bitboards and king attack zones for both sides ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.king_square(WHITE)); @@ -344,8 +380,8 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8); // Initialize pawn attack bitboards for both sides - ei.attackedBy[WHITE][PAWN] = ((pos.pieces(PAWN, WHITE) << 9) & ~FileABB) | ((pos.pieces(PAWN, WHITE) << 7) & ~FileHBB); - ei.attackedBy[BLACK][PAWN] = ((pos.pieces(PAWN, BLACK) >> 7) & ~FileABB) | ((pos.pieces(PAWN, BLACK) >> 9) & ~FileHBB); + ei.attackedBy[WHITE][PAWN] = ei.pi->pawn_attacks(WHITE); + ei.attackedBy[BLACK][PAWN] = ei.pi->pawn_attacks(BLACK); Bitboard b1 = ei.attackedBy[WHITE][PAWN] & ei.attackedBy[BLACK][KING]; Bitboard b2 = ei.attackedBy[BLACK][PAWN] & ei.attackedBy[WHITE][KING]; if (b1) @@ -364,9 +400,14 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { evaluate_king(pos, ei); evaluate_king(pos, ei); + // Evaluate tactical threats, we need full attack info + evaluate_threats(pos, ei); + evaluate_threats(pos, ei); + // Evaluate passed pawns. We evaluate passed pawns for both sides at once, // because we need to know which side promotes first in positions where - // both sides have an unstoppable passed pawn. + // both sides have an unstoppable passed pawn. To be called after all attacks + // are computed, included king. if (ei.pi->passed_pawns()) evaluate_passed_pawns(pos, ei); @@ -379,14 +420,12 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { if ( square_file(pos.king_square(WHITE)) >= FILE_E && square_file(pos.king_square(BLACK)) <= FILE_D) - ei.mgValue += ei.pi->queenside_storm_value(WHITE) - - ei.pi->kingside_storm_value(BLACK); + ei.value += Score(ei.pi->queenside_storm_value(WHITE) - ei.pi->kingside_storm_value(BLACK), 0); else if ( square_file(pos.king_square(WHITE)) <= FILE_D && square_file(pos.king_square(BLACK)) >= FILE_E) - ei.mgValue += ei.pi->kingside_storm_value(WHITE) - - ei.pi->queenside_storm_value(BLACK); + ei.value += Score(ei.pi->kingside_storm_value(WHITE) - ei.pi->queenside_storm_value(BLACK), 0); // Evaluate space for both sides if (ei.mi->space_weight() > 0) @@ -397,15 +436,14 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { } // Mobility - ei.mgValue += apply_weight(ei.mgMobility, WeightMobilityMidgame); - ei.egValue += apply_weight(ei.egMobility, WeightMobilityEndgame); + ei.value += apply_weight(Score(ei.mgMobility, ei.egMobility), WeightMobilityMidgame, WeightMobilityEndgame); // If we don't already have an unusual scale factor, check for opposite // colored bishop endgames, and use a lower scale for those if ( phase < PHASE_MIDGAME && pos.opposite_colored_bishops() - && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && ei.egValue > Value(0)) - || (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.egValue < Value(0)))) + && ( (factor[WHITE] == SCALE_FACTOR_NORMAL && ei.value.eg() > Value(0)) + || (factor[BLACK] == SCALE_FACTOR_NORMAL && ei.value.eg() < Value(0)))) { ScaleFactor sf; @@ -432,7 +470,7 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { // Interpolate between the middle game and the endgame score Color stm = pos.side_to_move(); - Value v = Sign[stm] * scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor); + Value v = Sign[stm] * scale_by_game_phase(ei.value, phase, factor); return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v); } @@ -450,12 +488,10 @@ Value quick_evaluate(const Position &pos) { static const ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; - Value mgv = pos.mg_value(); - Value egv = pos.eg_value(); Phase ph = pos.game_phase(); Color stm = pos.side_to_move(); - return Sign[stm] * scale_by_game_phase(mgv, egv, ph, sf); + return Sign[stm] * scale_by_game_phase(pos.value(), ph, sf); } @@ -529,7 +565,7 @@ namespace { // evaluate_mobility() computes mobility and attacks for every piece template - int evaluate_mobility(const Position& pos, const Bitboard& mob_bb, EvalInfo& ei) { + int evaluate_mobility(Bitboard b, Bitboard mob_area, EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight }; @@ -537,23 +573,21 @@ namespace { static const Value* EgBonus[] = { 0, 0, EndgameKnightMobilityBonus, EndgameBishopMobilityBonus, EndgameRookMobilityBonus, EndgameQueenMobilityBonus }; // Update attack info - ei.attackedBy[Us][Piece] |= mob_bb; + ei.attackedBy[Us][Piece] |= b; // King attacks - if (mob_bb & ei.kingZone[Us]) + if (b & ei.kingZone[Us]) { ei.kingAttackersCount[Us]++; ei.kingAttackersWeight[Us] += AttackWeight[Piece]; - Bitboard b = (mob_bb & ei.attackedBy[Them][KING]); - if (b) - ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15(b); + Bitboard bb = (b & ei.attackedBy[Them][KING]); + if (bb) + ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15(bb); } - // Remove squares protected by enemy pawns or occupied by our pieces - Bitboard b = mob_bb & ~ei.attackedBy[Them][PAWN] & ~pos.pieces_of_color(Us); - // Mobility - int mob = (Piece != QUEEN ? count_1s_max_15(b) : count_1s(b)); + int mob = (Piece != QUEEN ? count_1s_max_15(b & mob_area) + : count_1s(b & mob_area)); ei.mgMobility += Sign[Us] * MgBonus[Piece][mob]; ei.egMobility += Sign[Us] * EgBonus[Piece][mob]; @@ -582,8 +616,7 @@ namespace { else bonus += bonus / 2; } - ei.mgValue += Sign[Us] * bonus; - ei.egValue += Sign[Us] * bonus; + ei.value += Sign[Us] * Score(bonus, bonus); } @@ -592,7 +625,7 @@ namespace { template void evaluate_pieces(const Position& pos, EvalInfo& ei) { - Bitboard mob_bb; + Bitboard b; Square s, ksq; int mob; File f; @@ -600,19 +633,27 @@ namespace { const Color Them = (Us == WHITE ? BLACK : WHITE); const Square* ptr = pos.piece_list_begin(Us, Piece); + // Do not include in mobility squares protected by enemy pawns or occupied by our pieces + const Bitboard mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us)); + while ((s = *ptr++) != SQ_NONE) { if (Piece == KNIGHT || Piece == QUEEN) - mob_bb = pos.attacks_from(s); + b = pos.attacks_from(s); else if (Piece == BISHOP) - mob_bb = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(QUEEN, Us)); + b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(QUEEN, Us)); else if (Piece == ROOK) - mob_bb = rook_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(ROOK, QUEEN, Us)); + b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(ROOK, QUEEN, Us)); else assert(false); // Attacks and mobility - mob = evaluate_mobility(pos, mob_bb, ei); + mob = evaluate_mobility(b, mob_area, ei); + + // Decrease score if we are attacked by an enemy pawn. Remaining part + // of threat evaluation must be done later when we have full attack info. + if (bit_is_set(ei.attackedBy[Them][PAWN], s)) + ei.value -= Sign[Us] * Score(MidgameThreatedByPawnPenalty[Piece], EndgameThreatedByPawnPenalty[Piece]); // Bishop and knight outposts squares if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Them)) @@ -635,8 +676,8 @@ namespace { if ( relative_rank(Us, s) == RANK_7 && relative_rank(Us, pos.king_square(Them)) == RANK_8) { - ei.mgValue += Sign[Us] * (Piece == ROOK ? MidgameRookOn7thBonus : MidgameQueenOn7thBonus); - ei.egValue += Sign[Us] * (Piece == ROOK ? EndgameRookOn7thBonus : EndgameQueenOn7thBonus); + ei.value += Sign[Us] * (Piece == ROOK ? Score(MidgameRookOn7thBonus, EndgameRookOn7thBonus) + : Score(MidgameQueenOn7thBonus, EndgameQueenOn7thBonus)); } } @@ -648,15 +689,9 @@ namespace { if (ei.pi->file_is_half_open(Us, f)) { if (ei.pi->file_is_half_open(Them, f)) - { - ei.mgValue += Sign[Us] * RookOpenFileBonus; - ei.egValue += Sign[Us] * RookOpenFileBonus; - } + ei.value += Sign[Us] * Score(RookOpenFileBonus, RookOpenFileBonus); else - { - ei.mgValue += Sign[Us] * RookHalfOpenFileBonus; - ei.egValue += Sign[Us] * RookHalfOpenFileBonus; - } + ei.value += Sign[Us] * Score(RookHalfOpenFileBonus, RookHalfOpenFileBonus); } // Penalize rooks which are trapped inside a king. Penalize more if @@ -672,8 +707,8 @@ namespace { { // Is there a half-open file between the king and the edge of the board? if (!ei.pi->has_open_file_to_right(Us, square_file(ksq))) - ei.mgValue -= pos.can_castle(Us)? Sign[Us] * ((TrappedRookPenalty - mob * 16) / 2) - : Sign[Us] * (TrappedRookPenalty - mob * 16); + ei.value -= Sign[Us] * Score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 + : (TrappedRookPenalty - mob * 16), 0); } else if ( square_file(ksq) <= FILE_D && square_file(s) < square_file(ksq) @@ -681,14 +716,47 @@ namespace { { // Is there a half-open file between the king and the edge of the board? if (!ei.pi->has_open_file_to_left(Us, square_file(ksq))) - ei.mgValue -= pos.can_castle(Us)? Sign[Us] * ((TrappedRookPenalty - mob * 16) / 2) - : Sign[Us] * (TrappedRookPenalty - mob * 16); + ei.value -= Sign[Us] * Score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 + : (TrappedRookPenalty - mob * 16), 0); } } } } + // evaluate_threats<>() assigns bonuses according to the type of attacking piece + // and the type of attacked one. + + template + void evaluate_threats(const Position& pos, EvalInfo& ei) { + + const Color Them = (Us == WHITE ? BLACK : WHITE); + + Bitboard b; + Score bonus(0, 0); + + // Enemy pieces not defended by a pawn and under our attack + Bitboard weakEnemies = pos.pieces_of_color(Them) + & ~ei.attackedBy[Them][PAWN] + & ei.attackedBy[Us][0]; + if (!weakEnemies) + return; + + // Add bonus according to type of attacked enemy pieces and to the + // type of attacking piece, from knights to queens. Kings are not + // considered because are already special handled in king evaluation. + for (PieceType pt1 = KNIGHT; pt1 < KING; pt1++) + { + b = ei.attackedBy[Us][pt1] & weakEnemies; + if (b) + for (PieceType pt2 = PAWN; pt2 < KING; pt2++) + if (b & pos.pieces(pt2)) + bonus += Score(MidgameThreatBonus[pt1][pt2], EndgameThreatBonus[pt1][pt2]); + } + ei.value += Sign[Us] * bonus; + } + + // evaluate_pieces_of_color<>() assigns bonuses and penalties to all the // pieces of a given color. @@ -720,7 +788,7 @@ namespace { if (relative_rank(Us, s) <= RANK_4) { shelter = ei.pi->get_king_shelter(pos, Us, s); - ei.mgValue += Sign[Us] * Value(shelter); + ei.value += Sign[Us] * Score(shelter, 0); } // King safety. This is quite complicated, and is almost certainly far @@ -869,7 +937,7 @@ namespace { // change far bigger than the value of the captured piece. Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[Us]); - ei.mgValue -= Sign[Us] * v; + ei.value -= Sign[Us] * Score(v, 0); if (Us == pos.side_to_move()) ei.futilityMargin += v; @@ -877,158 +945,193 @@ namespace { } - // evaluate_passed_pawns() evaluates the passed pawns for both sides + // evaluate_passed_pawns() evaluates the passed pawns of the given color - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { + template + void evaluate_passed_pawns_of_color(const Position& pos, int movesToGo[], Square pawnToGo[], EvalInfo& ei) { - bool hasUnstoppable[2] = {false, false}; - int movesToGo[2] = {100, 100}; + const Color Them = (Us == WHITE ? BLACK : WHITE); - for (Color us = WHITE; us <= BLACK; us++) + Bitboard b2, b3, b4; + Square ourKingSq = pos.king_square(Us); + Square theirKingSq = pos.king_square(Them); + Bitboard b = ei.pi->passed_pawns() & pos.pieces(PAWN, Us); + + while (b) { - Color them = opposite_color(us); - Square ourKingSq = pos.king_square(us); - Square theirKingSq = pos.king_square(them); - Bitboard b = ei.pi->passed_pawns() & pos.pieces(PAWN, us), b2, b3, b4; + Square s = pop_1st_bit(&b); - while (b) - { - Square s = pop_1st_bit(&b); + assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN)); + assert(pos.pawn_is_passed(Us, s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, PAWN)); - assert(pos.pawn_is_passed(us, s)); + int r = int(relative_rank(Us, s) - RANK_2); + int tr = Max(0, r * (r - 1)); - int r = int(relative_rank(us, s) - RANK_2); - int tr = Max(0, r * (r - 1)); - Square blockSq = s + pawn_push(us); + // Base bonus based on rank + Value mbonus = Value(20 * tr); + Value ebonus = Value(10 + r * r * 10); - // Base bonus based on rank - Value mbonus = Value(20 * tr); - Value ebonus = Value(10 + r * r * 10); + // Adjust bonus based on king proximity + if (tr) + { + Square blockSq = s + pawn_push(Us); + + ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr); + ebonus -= Value(square_distance(ourKingSq, blockSq + pawn_push(Us)) * 1 * tr); + ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr); - // Adjust bonus based on king proximity - if (tr != 0) + // If the pawn is free to advance, increase bonus + if (pos.square_is_empty(blockSq)) { - ebonus -= Value(square_distance(ourKingSq, blockSq) * 3 * tr); - ebonus -= Value(square_distance(ourKingSq, blockSq + pawn_push(us)) * 1 * tr); - ebonus += Value(square_distance(theirKingSq, blockSq) * 6 * tr); + // There are no enemy pawns in the pawn's path + b2 = squares_in_front_of(Us, s); - // If the pawn is free to advance, increase bonus - if (pos.square_is_empty(blockSq)) - { - b2 = squares_in_front_of(us, s); - b3 = b2 & ei.attacked_by(them); - b4 = b2 & ei.attacked_by(us); - - // If there is an enemy rook or queen attacking the pawn from behind, - // add all X-ray attacks by the rook or queen. - if ( bit_is_set(ei.attacked_by(them,ROOK) | ei.attacked_by(them,QUEEN),s) - && (squares_behind(us, s) & pos.pieces(ROOK, QUEEN, them))) - b3 = b2; - - // Squares attacked or occupied by enemy pieces - b3 |= (b2 & pos.pieces_of_color(them)); - - // There are no enemy pawns in the pawn's path - assert((b2 & pos.pieces(PAWN, them)) == EmptyBoardBB); - - // Are any of the squares in the pawn's path attacked or occupied by the enemy? - if (b3 == EmptyBoardBB) - // No enemy attacks or pieces, huge bonus! - ebonus += Value(tr * (b2 == b4 ? 17 : 15)); - else - // OK, there are enemy attacks or pieces (but not pawns). Are those - // squares which are attacked by the enemy also attacked by us? - // If yes, big bonus (but smaller than when there are no enemy attacks), - // if no, somewhat smaller bonus. - ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8)); - - // At last, add a small bonus when there are no *friendly* pieces - // in the pawn's path. - if ((b2 & pos.pieces_of_color(us)) == EmptyBoardBB) - ebonus += Value(tr); - } - } + assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB); - // If the pawn is supported by a friendly pawn, increase bonus - b2 = pos.pieces(PAWN, us) & neighboring_files_bb(s); - if (b2 & rank_bb(s)) - ebonus += Value(r * 20); - else if (pos.attacks_from(s, them) & b2) - ebonus += Value(r * 12); + // Squares attacked by us + b4 = b2 & ei.attacked_by(Us); - // If the other side has only a king, check whether the pawn is - // unstoppable - if (pos.non_pawn_material(them) == Value(0)) - { - Square qsq; - int d; + // Squares attacked or occupied by enemy pieces + b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); - qsq = relative_square(us, make_square(square_file(s), RANK_8)); - d = square_distance(s, qsq) - - square_distance(theirKingSq, qsq) - + (us != pos.side_to_move()); + // If there is an enemy rook or queen attacking the pawn from behind, + // add all X-ray attacks by the rook or queen. + if ( (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them)) + && (squares_behind(Us, s) & pos.pieces(ROOK, QUEEN, Them) & pos.attacks_from(s))) + b3 = b2; - if (d < 0) - { - int mtg = RANK_8 - relative_rank(us, s); - int blockerCount = count_1s_max_15(squares_in_front_of(us,s) & pos.occupied_squares()); - mtg += blockerCount; - d += blockerCount; - if (d < 0) - { - hasUnstoppable[us] = true; - movesToGo[us] = Min(movesToGo[us], mtg); - } - } + // Are any of the squares in the pawn's path attacked or occupied by the enemy? + if (b3 == EmptyBoardBB) + // No enemy attacks or pieces, huge bonus! + // Even bigger if we protect the pawn's path + ebonus += Value(tr * (b2 == b4 ? 17 : 15)); + else + // OK, there are enemy attacks or pieces (but not pawns). Are those + // squares which are attacked by the enemy also attacked by us ? + // If yes, big bonus (but smaller than when there are no enemy attacks), + // if no, somewhat smaller bonus. + ebonus += Value(tr * ((b3 & b4) == b3 ? 13 : 8)); + + // At last, add a small bonus when there are no *friendly* pieces + // in the pawn's path. + if ((b2 & pos.pieces_of_color(Us)) == EmptyBoardBB) + ebonus += Value(tr); } - // Rook pawns are a special case: They are sometimes worse, and - // sometimes better than other passed pawns. It is difficult to find - // good rules for determining whether they are good or bad. For now, - // we try the following: Increase the value for rook pawns if the - // other side has no pieces apart from a knight, and decrease the - // value if the other side has a rook or queen. - if (square_file(s) == FILE_A || square_file(s) == FILE_H) + } // tr != 0 + + // If the pawn is supported by a friendly pawn, increase bonus + b2 = pos.pieces(PAWN, Us) & neighboring_files_bb(s); + if (b2 & rank_bb(s)) + ebonus += Value(r * 20); + else if (pos.attacks_from(s, Them) & b2) + ebonus += Value(r * 12); + + // If the other side has only a king, check whether the pawn is + // unstoppable + if (pos.non_pawn_material(Them) == Value(0)) + { + Square qsq; + int d; + + qsq = relative_square(Us, make_square(square_file(s), RANK_8)); + d = square_distance(s, qsq) + - square_distance(theirKingSq, qsq) + + (Us != pos.side_to_move()); + + if (d < 0) { - if ( pos.non_pawn_material(them) <= KnightValueMidgame - && pos.piece_count(them, KNIGHT) <= 1) - ebonus += ebonus / 4; - else if (pos.pieces(ROOK, QUEEN, them)) - ebonus -= ebonus / 4; + int mtg = RANK_8 - relative_rank(Us, s); + int blockerCount = count_1s_max_15(squares_in_front_of(Us,s) & pos.occupied_squares()); + mtg += blockerCount; + d += blockerCount; + if (d < 0 && (!movesToGo[Us] || movesToGo[Us] > mtg)) + { + movesToGo[Us] = mtg; + pawnToGo[Us] = s; + } } + } - // Add the scores for this pawn to the middle game and endgame eval. - ei.mgValue += apply_weight(Sign[us] * mbonus, WeightPassedPawnsMidgame); - ei.egValue += apply_weight(Sign[us] * ebonus, WeightPassedPawnsEndgame); + // Rook pawns are a special case: They are sometimes worse, and + // sometimes better than other passed pawns. It is difficult to find + // good rules for determining whether they are good or bad. For now, + // we try the following: Increase the value for rook pawns if the + // other side has no pieces apart from a knight, and decrease the + // value if the other side has a rook or queen. + if (square_file(s) == FILE_A || square_file(s) == FILE_H) + { + if ( pos.non_pawn_material(Them) <= KnightValueMidgame + && pos.piece_count(Them, KNIGHT) <= 1) + ebonus += ebonus / 4; + else if (pos.pieces(ROOK, QUEEN, Them)) + ebonus -= ebonus / 4; } - } - // Does either side have an unstoppable passed pawn? - if (hasUnstoppable[WHITE] && !hasUnstoppable[BLACK]) - ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]); - else if (hasUnstoppable[BLACK] && !hasUnstoppable[WHITE]) - ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]); - else if (hasUnstoppable[BLACK] && hasUnstoppable[WHITE]) + // Add the scores for this pawn to the middle game and endgame eval. + ei.value += Score(apply_weight(Sign[Us] * mbonus, WeightPassedPawnsMidgame), + apply_weight(Sign[Us] * ebonus, WeightPassedPawnsEndgame)); + + } // while + } + + + // evaluate_passed_pawns() evaluates the passed pawns for both sides + + void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { + + int movesToGo[2] = {0, 0}; + Square pawnToGo[2] = {SQ_NONE, SQ_NONE}; + + // Evaluate pawns for each color + evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); + evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); + + // Neither side has an unstoppable passed pawn? + if (!(movesToGo[WHITE] | movesToGo[BLACK])) + return; + + // Does only one side have an unstoppable passed pawn? + if (!movesToGo[WHITE] || !movesToGo[BLACK]) { - // Both sides have unstoppable pawns! Try to find out who queens + Color winnerSide = movesToGo[WHITE] ? WHITE : BLACK; + ei.value += Score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * movesToGo[winnerSide]))); + } + else + { // Both sides have unstoppable pawns! Try to find out who queens // first. We begin by transforming 'movesToGo' to the number of // plies until the pawn queens for both sides. movesToGo[WHITE] *= 2; movesToGo[BLACK] *= 2; movesToGo[pos.side_to_move()]--; - // If one side queens at least three plies before the other, that - // side wins. - if (movesToGo[WHITE] <= movesToGo[BLACK] - 3) - ei.egValue += UnstoppablePawnValue - Value(0x40 * (movesToGo[WHITE]/2)); - else if (movesToGo[BLACK] <= movesToGo[WHITE] - 3) - ei.egValue -= UnstoppablePawnValue - Value(0x40 * (movesToGo[BLACK]/2)); - - // We could also add some rules about the situation when one side - // queens exactly one ply before the other: Does the first queen - // check the opponent's king, or attack the opponent's queening square? - // This is slightly tricky to get right, because it is possible that - // the opponent's king has moved somewhere before the first pawn queens. + Color winnerSide = movesToGo[WHITE] < movesToGo[BLACK] ? WHITE : BLACK; + Color loserSide = opposite_color(winnerSide); + + // If one side queens at least three plies before the other, that side wins + if (movesToGo[winnerSide] <= movesToGo[loserSide] - 3) + ei.value += Score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2)))); + + // If one side queens one ply before the other and checks the king or attacks + // the undefended opponent's queening square, that side wins. To avoid cases + // where the opponent's king could move somewhere before first pawn queens we + // consider only free paths to queen for both pawns. + else if ( !(squares_in_front_of(WHITE, pawnToGo[WHITE]) & pos.occupied_squares()) + && !(squares_in_front_of(BLACK, pawnToGo[BLACK]) & pos.occupied_squares())) + { + assert(movesToGo[loserSide] - movesToGo[winnerSide] == 1); + + Square winnerQSq = relative_square(winnerSide, make_square(square_file(pawnToGo[winnerSide]), RANK_8)); + Square loserQSq = relative_square(loserSide, make_square(square_file(pawnToGo[loserSide]), RANK_8)); + + Bitboard b = pos.occupied_squares(); + clear_bit(&b, pawnToGo[winnerSide]); + clear_bit(&b, pawnToGo[loserSide]); + b = queen_attacks_bb(winnerQSq, b); + + if ( (b & pos.pieces(KING, loserSide)) + ||(bit_is_set(b, loserQSq) && !bit_is_set(ei.attacked_by(loserSide), loserQSq))) + ei.value += Score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2)))); + } } } @@ -1049,8 +1152,7 @@ namespace { && pos.see(s, b6) < 0 && pos.see(s, b8) < 0) { - ei.mgValue -= Sign[us] * TrappedBishopA7H7Penalty; - ei.egValue -= Sign[us] * TrappedBishopA7H7Penalty; + ei.value -= Sign[us] * Score(TrappedBishopA7H7Penalty, TrappedBishopA7H7Penalty); } } @@ -1093,8 +1195,7 @@ namespace { else penalty = TrappedBishopA1H1Penalty / 2; - ei.mgValue -= Sign[us] * penalty; - ei.egValue -= Sign[us] * penalty; + ei.value -= Sign[us] * Score(penalty, penalty); } } @@ -1128,7 +1229,7 @@ namespace { int space = count_1s_max_15(safeSquares) + count_1s_max_15(behindFriendlyPawns & safeSquares); - ei.mgValue += Sign[Us] * apply_weight(Value(space * ei.mi->space_weight()), WeightSpace); + ei.value += Sign[Us] * Score(apply_weight(Value(space * ei.mi->space_weight()), WeightSpace), 0); } @@ -1138,20 +1239,24 @@ namespace { return (v*w) / 0x100; } + inline Score apply_weight(Score v, int wmg, int weg) { + return Score(v.mg()*wmg, v.eg()*weg) / 0x100; + } + // scale_by_game_phase() interpolates between a middle game and an endgame // score, based on game phase. It also scales the return value by a // ScaleFactor array. - Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) { + Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]) { - assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE); - assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE); + assert(v.mg() > -VALUE_INFINITE && v.mg() < VALUE_INFINITE); + assert(v.eg() > -VALUE_INFINITE && v.eg() < VALUE_INFINITE); assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); - ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]); + Value ev = apply_scale_factor(v.eg(), sf[(v.eg() > Value(0) ? WHITE : BLACK)]); - Value result = Value(int((mv * ph + ev * (128 - ph)) / 128)); + Value result = Value(int((v.mg() * ph + ev * (128 - ph)) / 128)); return Value(int(result) & ~(GrainSize - 1)); } @@ -1208,3 +1313,8 @@ namespace { } } } + +std::ostream& operator<<(std::ostream &os, Score s) { + + return os << "(" << s.mg() << ", " << s.eg() << ")"; +}