X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fevaluate.cpp;h=da4b9c30b41c3e9d3f4ac17641e7a8fcb3f28233;hb=29b5842da8d5477c0aea924cfd364c9e619456a2;hp=86e5999f85cfe49fd899ee38ae34a2a5fd4309cb;hpb=189a005a0be8dc255ae1e5f2d4d8c416f6b0db75;p=stockfish diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 86e5999f..da4b9c30 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -1,7 +1,8 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2009 Marco Costalba + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -17,1222 +18,871 @@ along with this program. If not, see . */ - -//// -//// Includes -//// - +#include #include -#include +#include // For std::memset +#include +#include -#include "bitcount.h" +#include "bitboard.h" #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "scale.h" -#include "thread.h" -#include "ucioption.h" - - -//// -//// Local definitions -//// namespace { - const int Sign[2] = { 1, -1 }; + namespace Trace { - // Evaluation grain size, must be a power of 2 - const int GrainSize = 8; + enum Term { // The first 8 entries are for PieceType + MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERM_NB + }; - // Evaluation weights, initialized from UCI options - Score WeightMobility, WeightPawnStructure; - Score WeightPassedPawns, WeightSpace; - Score WeightKingSafety[2]; + double scores[TERM_NB][COLOR_NB][PHASE_NB]; - // Internal evaluation weights. These are applied on top of the evaluation - // weights read from UCI parameters. The purpose is to be able to change - // the evaluation weights while keeping the default values of the UCI - // parameters at 100, which looks prettier. - // - // Values modified by Joona Kiiski - const Score WeightMobilityInternal = make_score(248, 271); - const Score WeightPawnStructureInternal = make_score(233, 201); - const Score WeightPassedPawnsInternal = make_score(252, 259); - const Score WeightSpaceInternal = make_score( 46, 0); - const Score WeightKingSafetyInternal = make_score(247, 0); - const Score WeightKingOppSafetyInternal = make_score(259, 0); + double to_cp(Value v) { return double(v) / PawnValueEg; } - // Mobility and outposts bonus modified by Joona Kiiski + void add(int idx, Color c, Score s) { + scores[idx][c][MG] = to_cp(mg_value(s)); + scores[idx][c][EG] = to_cp(eg_value(s)); + } - typedef Value V; - #define S(mg, eg) make_score(mg, eg) + void add(int idx, Score w, Score b = SCORE_ZERO) { + add(idx, WHITE, w); add(idx, BLACK, b); + } - CACHE_LINE_ALIGNMENT + std::ostream& operator<<(std::ostream& os, Term t) { - // Knight mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly piecess. - const Score KnightMobilityBonus[16] = { - S(-38,-33), S(-25,-23), S(-12,-13), S( 0,-3), - S( 12, 7), S( 25, 17), S( 31, 22), S(38, 27), S(38, 27) - }; + if (t == MATERIAL || t == IMBALANCE || t == Term(PAWN) || t == TOTAL) + os << " --- --- | --- --- | "; + else + os << std::setw(5) << scores[t][WHITE][MG] << " " + << std::setw(5) << scores[t][WHITE][EG] << " | " + << std::setw(5) << scores[t][BLACK][MG] << " " + << std::setw(5) << scores[t][BLACK][EG] << " | "; - // Bishop mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. X-ray attacks through - // queens are also included. - const Score BishopMobilityBonus[16] = { - S(-25,-30), S(-11,-16), S( 3, -2), S(17, 12), - S( 31, 26), S( 45, 40), S(57, 52), S(65, 60), - S( 71, 65), S( 74, 69), S(76, 71), S(78, 73), - S( 79, 74), S( 80, 75), S(81, 76), S(81, 76) - }; + os << std::setw(5) << scores[t][WHITE][MG] - scores[t][BLACK][MG] << " " + << std::setw(5) << scores[t][WHITE][EG] - scores[t][BLACK][EG] << " \n"; - // Rook mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. X-ray attacks through - // queens and rooks are also included. - const Score RookMobilityBonus[16] = { - S(-20,-36), S(-14,-19), S(-8, -3), S(-2, 13), - S( 4, 29), S( 10, 46), S(14, 62), S(19, 79), - S( 23, 95), S( 26,106), S(27,111), S(28,114), - S( 29,116), S( 30,117), S(31,118), S(32,118) - }; + return os; + } + } - // Queen mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. - const Score QueenMobilityBonus[32] = { - S(-10,-18), S(-8,-13), S(-6, -7), S(-3, -2), S(-1, 3), S( 1, 8), - S( 3, 13), S( 5, 19), S( 8, 23), S(10, 27), S(12, 32), S(15, 34), - S( 16, 35), S(17, 35), S(18, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), S(20, 35), - S( 20, 35), S(20, 35) + using namespace Trace; + + // Struct EvalInfo contains various information computed and collected + // by the evaluation functions. + struct EvalInfo { + + // attackedBy[color][piece type] is a bitboard representing all squares + // attacked by a given color and piece type (can be also ALL_PIECES). + Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB]; + + // kingRing[color] is the zone around the king which is considered + // by the king safety evaluation. This consists of the squares directly + // adjacent to the king, and the three (or two, for a king on an edge file) + // squares two ranks in front of the king. For instance, if black's king + // is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8, + // f7, g7, h7, f6, g6 and h6. + Bitboard kingRing[COLOR_NB]; + + // kingAttackersCount[color] is the number of pieces of the given color + // which attack a square in the kingRing of the enemy king. + int kingAttackersCount[COLOR_NB]; + + // kingAttackersWeight[color] is the sum of the "weights" 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 elements in the + // KingAttackWeights array. + int kingAttackersWeight[COLOR_NB]; + + // 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]; + Material::Entry* me; + Pawns::Entry* pi; }; - // Pointers table to access mobility tables through piece type - const Score* MobilityBonus[8] = { 0, 0, KnightMobilityBonus, BishopMobilityBonus, - RookMobilityBonus, QueenMobilityBonus, 0, 0 }; - - // Outpost bonuses for knights and bishops, indexed by square (from white's - // point of view). - const Value KnightOutpostBonus[64] = { - // A B C D E F G H - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 1 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2 - V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), // 3 - V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), // 4 - V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), // 5 - V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0), // 6 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8 - }; + #define V(v) Value(v) + #define S(mg, eg) make_score(mg, eg) - const Value BishopOutpostBonus[64] = { - // A B C D E F G H - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 1 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 2 - V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), // 3 - V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), // 4 - V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), // 5 - V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0), // 6 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // 7 - V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0) // 8 + // MobilityBonus[PieceType][attacked] contains bonuses for middle and end + // game, indexed by piece type and number of attacked squares in the MobilityArea. + const Score MobilityBonus[][32] = { + {}, {}, + { S(-75,-76), S(-56,-54), S(- 9,-26), S( -2,-10), S( 6, 5), S( 15, 11), // Knights + S( 22, 26), S( 30, 28), S( 36, 29) }, + { S(-48,-58), S(-21,-19), S( 16, -2), S( 26, 12), S( 37, 22), S( 51, 42), // Bishops + S( 54, 54), S( 63, 58), S( 65, 63), S( 71, 70), S( 79, 74), S( 81, 86), + S( 92, 90), S( 97, 94) }, + { S(-56,-78), S(-25,-18), S(-11, 26), S( -5, 55), S( -4, 70), S( -1, 81), // Rooks + S( 8,109), S( 14,120), S( 21,128), S( 23,143), S( 31,154), S( 32,160), + S( 43,165), S( 49,168), S( 59,169) }, + { S(-40,-35), S(-25,-12), S( 2, 7), S( 4, 19), S( 14, 37), S( 24, 55), // Queens + S( 25, 62), S( 40, 76), S( 43, 79), S( 47, 87), S( 54, 94), S( 56,102), + S( 60,111), S( 70,116), S( 72,118), S( 73,122), S( 75,128), S( 77,130), + S( 85,133), S( 94,136), S( 99,140), S(108,157), S(112,158), S(113,161), + S(118,174), S(119,177), S(123,191), S(128,199) } }; - // ThreatBonus[][] contains bonus according to which piece type - // attacks which one. - #define Z S(0, 0) - - const Score ThreatBonus[8][8] = { - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, S(18,37), Z, S(37,47), S(55,97), S(55,97), Z, Z }, // KNIGHT attacks - { Z, S(18,37), S(37,47), Z, S(55,97), S(55,97), Z, Z }, // BISHOP attacks - { Z, S( 9,27), S(27,47), S(27,47), Z, S(37,47), Z, Z }, // ROOK attacks - { Z, S(27,37), S(27,37), S(27,37), S(27,37), Z, Z, Z }, // QUEEN attacks - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, Z, Z, Z, Z, Z, Z, Z }, // not used - { Z, Z, Z, Z, Z, Z, Z, Z } // not used + // 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(43,11), S(65,20) }, // Knights + { S(20, 3), S(29, 8) } // Bishops }; - // ThreatedByPawnPenalty[] contains a penalty according to which piece - // type is attacked by an enemy pawn. - const Score ThreatedByPawnPenalty[8] = { - Z, Z, S(56, 70), S(56, 70), S(76, 99), S(86, 118), Z, Z + // 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(35, 8) }, // Knights + { S( 8, 0), S(14, 4) } // Bishops }; - #undef Z - #undef S - - // Bonus for unstoppable passed pawns - const Value UnstoppablePawnValue = Value(0x500); - - // Rooks and queens on the 7th rank (modified by Joona Kiiski) - const Score RookOn7thBonus = make_score(47, 98); - const Score QueenOn7thBonus = make_score(27, 54); - - // Rooks on open files (modified by Joona Kiiski) - const Score RookOpenFileBonus = make_score(43, 43); - const Score RookHalfOpenFileBonus = make_score(19, 19); + // RookOnFile[semiopen/open] contains bonuses for each rook when there is no + // friendly pawn on the rook file. + const Score RookOnFile[2] = { S(20, 7), S(45, 20) }; + + // ThreatBySafePawn[PieceType] contains bonuses according to which piece + // type is attacked by a pawn which is protected or is not attacked. + const Score ThreatBySafePawn[PIECE_TYPE_NB] = { + S(0, 0), S(0, 0), S(176, 139), S(131, 127), S(217, 218), S(203, 215) }; + + // Threat[by minor/by rook][attacked PieceType] contains + // bonuses according to which piece type attacks which one. + // Attacks on lesser pieces which are pawn-defended are not considered. + const Score Threat[][PIECE_TYPE_NB] = { + { S(0, 0), S(0, 33), S(45, 43), S(46, 47), S(72,107), S(48,118) }, // by Minor + { S(0, 0), S(0, 25), S(40, 62), S(40, 59), S( 0, 34), S(35, 48) } // by Rook + }; - // Penalty for rooks trapped inside a friendly king which has lost the - // right to castle. - const Value TrappedRookPenalty = Value(180); + // ThreatByKing[on one/on many] contains bonuses for King attacks on + // pawns or pieces which are not pawn-defended. + const Score ThreatByKing[2] = { S(3, 62), S(9, 138) }; - // Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by - // enemy pawns. - const Score TrappedBishopA7H7Penalty = make_score(300, 300); + // 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(5), V( 5), V(31), V(73), V(166), V(252) }, + { V(7), V(14), V(38), V(73), V(166), V(252) } + }; - // Bitboard masks for detecting trapped bishops on a7/h7 (a2/h2 for black) - const Bitboard MaskA7H7[2] = { - ((1ULL << SQ_A7) | (1ULL << SQ_H7)), - ((1ULL << SQ_A2) | (1ULL << SQ_H2)) + // PassedFile[File] contains a bonus according to the file of a passed pawn + const Score PassedFile[FILE_NB] = { + S( 9, 10), S( 2, 10), S( 1, -8), S(-20,-12), + S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; + // Assorted bonuses and penalties used by evaluation + const Score MinorBehindPawn = S(16, 0); + const Score BishopPawns = S( 8, 12); + const Score RookOnPawn = S( 8, 24); + const Score TrappedRook = S(92, 0); + const Score Checked = S(20, 20); + const Score ThreatByHangingPawn = S(71, 61); + const Score LooseEnemies = S( 0, 25); + const Score Hanging = S(48, 27); + const Score ThreatByPawnPush = S(38, 22); + const Score Unstoppable = S( 0, 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 // happen in Chess960 games. - const Score TrappedBishopA1H1Penalty = make_score(100, 100); - - // Bitboard masks for detecting trapped bishops on a1/h1 (a8/h8 for black) - const Bitboard MaskA1H1[2] = { - ((1ULL << SQ_A1) | (1ULL << SQ_H1)), - ((1ULL << SQ_A8) | (1ULL << SQ_H8)) - }; - - // 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] = { - (1ULL< - Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID); + // Penalties for enemy's safe checks + const int QueenContactCheck = 89; + const int QueenCheck = 52; + const int RookCheck = 45; + const int BishopCheck = 5; + const int KnightCheck = 17; - template - void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei); - template - void evaluate_king(const Position& pos, EvalInfo& ei); + // eval_init() initializes king and attack bitboards for a given color + // adding pawn attacks. To be done at the beginning of the evaluation. template - void evaluate_threats(const Position& pos, EvalInfo& ei); - - template - void evaluate_space(const Position& pos, EvalInfo& ei); - - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei); - 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 Score apply_weight(Score v, Score weight); - Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]); - Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight); - void init_safety(); -} - - -//// -//// Functions -//// - -/// evaluate() is the main evaluation function. It always computes two -/// values, an endgame score and a middle game score, and interpolates -/// between them based on the remaining material. -Value evaluate(const Position& pos, EvalInfo& ei, int threadID) { - - return CpuHasPOPCNT ? do_evaluate(pos, ei, threadID) - : do_evaluate(pos, ei, threadID); -} - -namespace { - -template -Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { - - assert(pos.is_ok()); - assert(threadID >= 0 && threadID < MAX_THREADS); - assert(!pos.is_check()); + void eval_init(const Position& pos, EvalInfo& ei) { - memset(&ei, 0, sizeof(EvalInfo)); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); - // Initialize by reading the incrementally updated scores included in the - // position object (material + piece square tables) - ei.value = pos.value(); + ei.pinnedPieces[Us] = pos.pinned_pieces(Us); + Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.square(Them)); + ei.attackedBy[Them][ALL_PIECES] |= b; + ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); - // Probe the material hash table - ei.mi = MaterialTable[threadID]->get_material_info(pos); - ei.value += ei.mi->material_value(); - - // 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); - - // After get_material_info() call that modifies them - ScaleFactor factor[2]; - factor[WHITE] = ei.mi->scale_factor(pos, WHITE); - factor[BLACK] = ei.mi->scale_factor(pos, BLACK); - - // Probe the pawn hash table - ei.pi = PawnTable[threadID]->get_pawn_info(pos); - ei.value += apply_weight(ei.pi->pawns_value(), WeightPawnStructure); - - // Initialize king attack bitboards and king attack zones for both sides - ei.attackedBy[WHITE][KING] = pos.attacks_from(pos.king_square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.attacks_from(pos.king_square(BLACK)); - ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8); - ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8); - - // Initialize pawn attack bitboards for both sides - 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) - ei.kingAttackersCount[WHITE] = count_1s_max_15(b1)/2; - - if (b2) - ei.kingAttackersCount[BLACK] = count_1s_max_15(b2)/2; - - // Evaluate pieces - evaluate_pieces_of_color(pos, ei); - evaluate_pieces_of_color(pos, ei); - - // Kings. Kings are evaluated after all other pieces for both sides, - // because we need complete attack information for all pieces when computing - // the king safety evaluation. - 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. To be called after all attacks - // are computed, included king. - if (ei.pi->passed_pawns()) - evaluate_passed_pawns(pos, ei); - - Phase phase = ei.mi->game_phase(); - - // Middle-game specific evaluation terms - if (phase > PHASE_ENDGAME) - { - // Pawn storms in positions with opposite castling. - if ( square_file(pos.king_square(WHITE)) >= FILE_E - && square_file(pos.king_square(BLACK)) <= FILE_D) - - ei.value += make_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.value += make_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) + // Init king safety tables only if we are going to use them + if (pos.non_pawn_material(Us) >= QueenValueMg) { - evaluate_space(pos, ei); - evaluate_space(pos, ei); + ei.kingRing[Them] = b | shift_bb(b); + b &= ei.attackedBy[Us][PAWN]; + ei.kingAttackersCount[Us] = b ? popcount(b) : 0; + ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0; } + else + ei.kingRing[Them] = ei.kingAttackersCount[Us] = 0; } - // Mobility - ei.value += apply_weight(ei.mobility, WeightMobility); - // 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 && eg_value(ei.value) > Value(0)) - || (factor[BLACK] == SCALE_FACTOR_NORMAL && eg_value(ei.value) < Value(0)))) - { - ScaleFactor sf; - - // Only the two bishops ? - if ( pos.non_pawn_material(WHITE) == BishopValueMidgame - && pos.non_pawn_material(BLACK) == BishopValueMidgame) - { - // Check for KBP vs KB with only a single pawn that is almost - // certainly a draw or at least two pawns. - bool one_pawn = (pos.piece_count(WHITE, PAWN) + pos.piece_count(BLACK, PAWN) == 1); - sf = one_pawn ? ScaleFactor(8) : ScaleFactor(32); - } - else - // Endgame with opposite-colored bishops, but also other pieces. Still - // a bit drawish, but not as drawish as with only the two bishops. - sf = ScaleFactor(50); - - if (factor[WHITE] == SCALE_FACTOR_NORMAL) - factor[WHITE] = sf; - if (factor[BLACK] == SCALE_FACTOR_NORMAL) - factor[BLACK] = sf; - } + // evaluate_pieces() assigns bonuses and penalties to the pieces of a given + // color and type. - // Interpolate between the middle game and the endgame score - Color stm = pos.side_to_move(); + template + Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, + const Bitboard* mobilityArea) { + Bitboard b, bb; + Square s; + Score score = SCORE_ZERO; - Value v = Sign[stm] * scale_by_game_phase(ei.value, phase, factor); + 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); - return (ei.mateThreat[stm] == MOVE_NONE ? v : 8 * QueenValueMidgame - v); -} + ei.attackedBy[Us][Pt] = 0; -} // namespace + while ((s = *pl++) != SQ_NONE) + { + // Find attacked squares, including x-ray attacks for bishops and rooks + b = Pt == BISHOP ? attacks_bb(s, pos.pieces() ^ pos.pieces(Us, QUEEN)) + : Pt == ROOK ? attacks_bb< ROOK>(s, pos.pieces() ^ pos.pieces(Us, ROOK, QUEEN)) + : pos.attacks_from(s); -/// init_eval() initializes various tables used by the evaluation function + if (ei.pinnedPieces[Us] & s) + b &= LineBB[pos.square(Us)][s]; -void init_eval(int threads) { + ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; - assert(threads <= MAX_THREADS); + if (b & ei.kingRing[Them]) + { + ei.kingAttackersCount[Us]++; + ei.kingAttackersWeight[Us] += KingAttackWeights[Pt]; + bb = b & ei.attackedBy[Them][KING]; + if (bb) + ei.kingAdjacentZoneAttacksCount[Us] += popcount(bb); + } - for (int i = 0; i < MAX_THREADS; i++) - { - if (i >= threads) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - continue; - } - if (!PawnTable[i]) - PawnTable[i] = new PawnInfoTable(PawnTableSize); - if (!MaterialTable[i]) - MaterialTable[i] = new MaterialInfoTable(MaterialTableSize); - } -} + if (Pt == QUEEN) + b &= ~( ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] + | ei.attackedBy[Them][ROOK]); + int mob = popcount(b & mobilityArea[Us]); -/// quit_eval() releases heap-allocated memory at program termination + mobility[Us] += MobilityBonus[Pt][mob]; -void quit_eval() { + if (Pt == BISHOP || Pt == KNIGHT) + { + // 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)]; + } - for (int i = 0; i < MAX_THREADS; i++) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - } -} + // 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 the same color square as the 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) + { + // Bonus for aligning with enemy pawns on the same rank/file + if (relative_rank(Us, s) >= RANK_5) + { + Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; + if (alignedPawns) + score += RookOnPawn * popcount(alignedPawns); + } -/// read_weights() reads evaluation weights from the corresponding UCI parameters + // Bonus when on an open or semi-open file + if (ei.pi->semiopen_file(Us, file_of(s))) + score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))]; -void read_weights(Color us) { + // Penalize when trapped by the king, even more if the king cannot castle + else if (mob <= 3) + { + Square ksq = pos.square(Us); - Color them = opposite_color(us); + 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)); + } + } + } - WeightMobility = weight_option("Mobility (Middle Game)", "Mobility (Endgame)", WeightMobilityInternal); - WeightPawnStructure = weight_option("Pawn Structure (Middle Game)", "Pawn Structure (Endgame)", WeightPawnStructureInternal); - WeightPassedPawns = weight_option("Passed Pawns (Middle Game)", "Passed Pawns (Endgame)", WeightPassedPawnsInternal); - WeightSpace = weight_option("Space", "Space", WeightSpaceInternal); - WeightKingSafety[us] = weight_option("Cowardice", "Cowardice", WeightKingSafetyInternal); - WeightKingSafety[them] = weight_option("Aggressiveness", "Aggressiveness", WeightKingOppSafetyInternal); + if (DoTrace) + Trace::add(Pt, Us, score); - // If running in analysis mode, make sure we use symmetrical king safety. We do this - // by replacing both WeightKingSafety[us] and WeightKingSafety[them] by their average. - if (get_option_value_bool("UCI_AnalyseMode")) - { - WeightKingSafety[us] = (WeightKingSafety[us] + WeightKingSafety[them]) / 2; - WeightKingSafety[them] = WeightKingSafety[us]; + // Recursively call evaluate_pieces() of next piece type until KING is excluded + return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } - init_safety(); -} + template<> + Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } + template<> + Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } -namespace { - // evaluate_outposts() evaluates bishop and knight outposts squares + // evaluate_king() assigns bonuses and penalties to a king of a given color - template - void evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) { + template + Score evaluate_king(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); - // Initial bonus based on square - Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(Us, s)] - : KnightOutpostBonus[relative_square(Us, s)]); - - // Increase bonus if supported by pawn, especially if the opponent has - // no minor piece which can exchange the outpost piece - if (bonus && bit_is_set(ei.attackedBy[Us][PAWN], s)) - { - if ( pos.pieces(KNIGHT, Them) == EmptyBoardBB - && (SquaresByColorBB[square_color(s)] & pos.pieces(BISHOP, Them)) == EmptyBoardBB) - bonus += bonus + bonus / 2; - else - bonus += bonus / 2; - } - ei.value += Sign[Us] * make_score(bonus, bonus); - } + Bitboard undefended, b, b1, b2, safe; + int attackUnits; + const Square ksq = pos.square(Us); + // King shelter and enemy pawns storm + Score score = ei.pi->king_safety(pos, ksq); - // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given color - - template - void evaluate_pieces(const Position& pos, EvalInfo& ei, Bitboard no_mob_area) { - - Bitboard b; - Square s, ksq; - int mob; - File f; - - const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square* ptr = pos.piece_list_begin(Us, Piece); - - while ((s = *ptr++) != SQ_NONE) + // Main king safety evaluation + if (ei.kingAttackersCount[Them]) { - // Find attacked squares, including x-ray attacks for bishops and rooks - if (Piece == KNIGHT || Piece == QUEEN) - b = pos.attacks_from(s); - else if (Piece == BISHOP) - b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(QUEEN, Us)); - else if (Piece == ROOK) - b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(ROOK, QUEEN, Us)); - else - assert(false); - - // Update attack info - ei.attackedBy[Us][Piece] |= b; - - // King attacks - if (b & ei.kingZone[Us]) + // Find the attacked squares around the king which have no defenders + // apart from the king itself. + undefended = ei.attackedBy[Them][ALL_PIECES] + & ei.attackedBy[Us][KING] + & ~( ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] + | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK] + | ei.attackedBy[Us][QUEEN]); + + // Initialize the 'attackUnits' variable, which is used later on as an + // 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(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) + + 9 * ei.kingAdjacentZoneAttacksCount[Them] + + 27 * popcount(undefended) + + 11 * !!ei.pinnedPieces[Us] + - 64 * !pos.count(Them) + - mg_value(score) / 8; + + // Analyse the enemy's safe queen contact checks. Firstly, find the + // undefended squares around the king reachable by the enemy queen... + b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them); + if (b) { - ei.kingAttackersCount[Us]++; - ei.kingAttackersWeight[Us] += AttackWeight[Piece]; - Bitboard bb = (b & ei.attackedBy[Them][KING]); - if (bb) - ei.kingAdjacentZoneAttacksCount[Us] += count_1s_max_15(bb); + // ...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][KING]; + + if (b) + attackUnits += QueenContactCheck * popcount(b); } - // Mobility - mob = (Piece != QUEEN ? count_1s_max_15(b & no_mob_area) - : count_1s(b & no_mob_area)); + // Analyse the enemy's safe distance checks for sliders and knights + safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - ei.mobility += Sign[Us] * MobilityBonus[Piece][mob]; + b1 = pos.attacks_from(ksq) & safe; + b2 = pos.attacks_from(ksq) & safe; - // 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] * ThreatedByPawnPenalty[Piece]; + // Enemy queen safe checks + if ((b1 | b2) & ei.attackedBy[Them][QUEEN]) + attackUnits += QueenCheck, score -= Checked; - // Bishop and knight outposts squares - if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, Them)) - evaluate_outposts(pos, ei, s); + // Enemy rooks safe checks + if (b1 & ei.attackedBy[Them][ROOK]) + attackUnits += RookCheck, score -= Checked; - // Special patterns: trapped bishops on a7/h7/a2/h2 - // and trapped bishops on a1/h1/a8/h8 in Chess960. - if (Piece == BISHOP) - { - if (bit_is_set(MaskA7H7[Us], s)) - evaluate_trapped_bishop_a7h7(pos, s, Us, ei); + // Enemy bishops safe checks + if (b2 & ei.attackedBy[Them][BISHOP]) + attackUnits += BishopCheck, score -= Checked; - if (Chess960 && bit_is_set(MaskA1H1[Us], s)) - evaluate_trapped_bishop_a1h1(pos, s, Us, ei); - } + // Enemy knights safe checks + if (pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe) + attackUnits += KnightCheck, score -= Checked; - // Queen or rook on 7th rank - if ( (Piece == ROOK || Piece == QUEEN) - && relative_rank(Us, s) == RANK_7 - && relative_rank(Us, pos.king_square(Them)) == RANK_8) - { - ei.value += Sign[Us] * (Piece == ROOK ? RookOn7thBonus : QueenOn7thBonus); - } + // Finally, extract the king danger score from the KingDanger[] + // array and subtract the score from the evaluation. + score -= KingDanger[std::max(std::min(attackUnits, 399), 0)]; + } - // Special extra evaluation for rooks - if (Piece == ROOK) - { - // Open and half-open files - f = square_file(s); - if (ei.pi->file_is_half_open(Us, f)) - { - if (ei.pi->file_is_half_open(Them, f)) - ei.value += Sign[Us] * RookOpenFileBonus; - else - ei.value += Sign[Us] * RookHalfOpenFileBonus; - } + if (DoTrace) + Trace::add(KING, Us, score); - // Penalize rooks which are trapped inside a king. Penalize more if - // king has lost right to castle. - if (mob > 6 || ei.pi->file_is_half_open(Us, f)) - continue; + return score; + } - ksq = pos.king_square(Us); - if ( square_file(ksq) >= FILE_E - && square_file(s) > square_file(ksq) - && (relative_rank(Us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s))) - { - // 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.value -= Sign[Us] * make_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) - && (relative_rank(Us, ksq) == RANK_1 || square_rank(ksq) == square_rank(s))) - { - // 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.value -= Sign[Us] * make_score(pos.can_castle(Us) ? (TrappedRookPenalty - mob * 16) / 2 - : (TrappedRookPenalty - mob * 16), 0); - } - } - } - } + // evaluate_threats() assigns bonuses according to the types of the attacking + // and the attacked pieces. + template + Score evaluate_threats(const Position& pos, const EvalInfo& ei) { - // evaluate_threats<>() assigns bonuses according to the type of attacking piece - // and the type of attacked one. + 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); - template - void evaluate_threats(const Position& pos, EvalInfo& ei) { + enum { Minor, Rook }; - const Color Them = (Us == WHITE ? BLACK : WHITE); + Bitboard b, weak, defended, safeThreats; + Score score = SCORE_ZERO; - Bitboard b; - Score bonus = make_score(0, 0); + // Small bonus if the opponent has loose pawns or pieces + if ( (pos.pieces(Them) ^ pos.pieces(Them, QUEEN, KING)) + & ~(ei.attackedBy[Us][ALL_PIECES] | ei.attackedBy[Them][ALL_PIECES])) + score += LooseEnemies; - // 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; + // Non-pawn enemies attacked by a pawn + weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN]; - // 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++) + if (weak) { - b = ei.attackedBy[Us][pt1] & weakEnemies; - if (b) - for (PieceType pt2 = PAWN; pt2 < KING; pt2++) - if (b & pos.pieces(pt2)) - bonus += ThreatBonus[pt1][pt2]; - } - ei.value += Sign[Us] * bonus; - } + b = pos.pieces(Us, PAWN) & ( ~ei.attackedBy[Them][ALL_PIECES] + | ei.attackedBy[Us][ALL_PIECES]); + safeThreats = (shift_bb(b) | shift_bb(b)) & weak; - // evaluate_pieces_of_color<>() assigns bonuses and penalties to all the - // pieces of a given color. + if (weak ^ safeThreats) + score += ThreatByHangingPawn; - template - void evaluate_pieces_of_color(const Position& pos, EvalInfo& ei) { + while (safeThreats) + score += ThreatBySafePawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; + } - const Color Them = (Us == WHITE ? BLACK : WHITE); + // Non-pawn enemies defended by a pawn + defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Them][PAWN]; - // Do not include in mobility squares protected by enemy pawns or occupied by our pieces - const Bitboard no_mob_area = ~(ei.attackedBy[Them][PAWN] | pos.pieces_of_color(Us)); + // Enemies not defended by a pawn and under our attack + weak = pos.pieces(Them) + & ~ei.attackedBy[Them][PAWN] + & ei.attackedBy[Us][ALL_PIECES]; - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); - evaluate_pieces(pos, ei, no_mob_area); + // Add a bonus according to the kind of attacking pieces + if (defended | weak) + { + b = (defended | weak) & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + while (b) + score += Threat[Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - // Sum up all attacked squares - ei.attackedBy[Us][0] = ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] - | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK] - | ei.attackedBy[Us][QUEEN] | ei.attackedBy[Us][KING]; - } + b = (pos.pieces(Them, QUEEN) | weak) & ei.attackedBy[Us][ROOK]; + while (b) + score += Threat[Rook ][type_of(pos.piece_on(pop_lsb(&b)))]; + b = weak & ~ei.attackedBy[Them][ALL_PIECES]; + if (b) + score += Hanging * popcount(b); - // evaluate_king<>() assigns bonuses and penalties to a king of a given color + b = weak & ei.attackedBy[Us][KING]; + if (b) + score += ThreatByKing[more_than_one(b)]; + } - template - void evaluate_king(const Position& pos, EvalInfo& ei) { + // 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())); - const Color Them = (Us == WHITE ? BLACK : WHITE); + b &= ~pos.pieces() + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); - Bitboard undefended, attackedByOthers, escapeSquares, occ, b, b2, safe; - Square from, to; - bool sente; - int attackUnits, count, shelter = 0; - const Square s = pos.king_square(Us); + b = (shift_bb(b) | shift_bb(b)) + & pos.pieces(Them) + & ~ei.attackedBy[Us][PAWN]; - // King shelter - if (relative_rank(Us, s) <= RANK_4) - { - shelter = ei.pi->get_king_shelter(pos, Us, s); - ei.value += Sign[Us] * make_score(shelter, 0); - } + if (b) + score += ThreatByPawnPush * popcount(b); - // King safety. This is quite complicated, and is almost certainly far - // from optimally tuned. - if ( pos.piece_count(Them, QUEEN) >= 1 - && ei.kingAttackersCount[Them] >= 2 - && pos.non_pawn_material(Them) >= QueenValueMidgame + RookValueMidgame - && ei.kingAdjacentZoneAttacksCount[Them]) - { - // Is it the attackers turn to move? - sente = (Them == pos.side_to_move()); - - // Find the attacked squares around the king which has no defenders - // apart from the king itself - undefended = ei.attacked_by(Them) & ei.attacked_by(Us, KING); - undefended &= ~( ei.attacked_by(Us, PAWN) | ei.attacked_by(Us, KNIGHT) - | ei.attacked_by(Us, BISHOP) | ei.attacked_by(Us, ROOK) - | ei.attacked_by(Us, QUEEN)); - - // Initialize the 'attackUnits' variable, which is used later on as an - // index to the SafetyTable[] array. The initial value is based on the - // number and types of the attacking pieces, the number of attacked and - // undefended squares around the king, the square of the king, and the - // quality of the pawn shelter. - attackUnits = Min(25, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) - + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + count_1s_max_15(undefended)) - + InitKingDanger[relative_square(Us, s)] - - (shelter >> 5); - - // Analyse safe queen contact checks - b = undefended & ei.attacked_by(Them, QUEEN) & ~pos.pieces_of_color(Them); - if (b) - { - attackedByOthers = ei.attacked_by(Them, PAWN) | ei.attacked_by(Them, KNIGHT) - | ei.attacked_by(Them, BISHOP) | ei.attacked_by(Them, ROOK); - - b &= attackedByOthers; - - // Squares attacked by the queen and supported by another enemy piece and - // not defended by other pieces but our king. - if (b) - { - // The bitboard b now contains the squares available for safe queen - // contact checks. - count = count_1s_max_15(b); - attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1); + if (DoTrace) + Trace::add(THREAT, Us, score); - // Is there a mate threat? - if (QueenContactMates && !pos.is_check()) - { - escapeSquares = pos.attacks_from(s) & ~pos.pieces_of_color(Us) & ~attackedByOthers; - occ = pos.occupied_squares(); - while (b) - { - to = pop_1st_bit(&b); - - // Do we have escape squares from queen contact check attack ? - if (!(escapeSquares & ~queen_attacks_bb(to, occ & ClearMaskBB[s]))) - { - // We have a mate, unless the queen is pinned or there - // is an X-ray attack through the queen. - for (int i = 0; i < pos.piece_count(Them, QUEEN); i++) - { - from = pos.piece_list(Them, QUEEN, i); - if ( bit_is_set(pos.attacks_from(from), to) - && !bit_is_set(pos.pinned_pieces(Them), from) - && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(ROOK, QUEEN, Us)) - && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & pos.pieces(BISHOP, QUEEN, Us))) - - // Set the mate threat move - ei.mateThreat[Them] = make_move(from, to); - } - } - } - } - } - } - - // Analyse safe distance checks - safe = ~(pos.pieces_of_color(Them) | ei.attacked_by(Us)); - - if (QueenCheckBonus > 0 || RookCheckBonus > 0) - { - b = pos.attacks_from(s) & safe; - - // Queen checks - b2 = b & ei.attacked_by(Them, QUEEN); - if (b2) - attackUnits += QueenCheckBonus * count_1s_max_15(b2); - - // Rook checks - b2 = b & ei.attacked_by(Them, ROOK); - if (b2) - attackUnits += RookCheckBonus * count_1s_max_15(b2); - } - if (QueenCheckBonus > 0 || BishopCheckBonus > 0) - { - b = pos.attacks_from(s) & safe; - - // Queen checks - b2 = b & ei.attacked_by(Them, QUEEN); - if (b2) - attackUnits += QueenCheckBonus * count_1s_max_15(b2); - - // Bishop checks - b2 = b & ei.attacked_by(Them, BISHOP); - if (b2) - attackUnits += BishopCheckBonus * count_1s_max_15(b2); - } - if (KnightCheckBonus > 0) - { - b = pos.attacks_from(s) & safe; - - // Knight checks - b2 = b & ei.attacked_by(Them, KNIGHT); - if (b2) - attackUnits += KnightCheckBonus * count_1s_max_15(b2); - } - - // Analyse discovered checks (only for non-pawns right now, consider - // adding pawns later). - if (DiscoveredCheckBonus) - { - b = pos.discovered_check_candidates(Them) & ~pos.pieces(PAWN); - if (b) - attackUnits += DiscoveredCheckBonus * count_1s_max_15(b) * (sente ? 2 : 1); - } - - // Has a mate threat been found? We don't do anything here if the - // side with the mating move is the side to move, because in that - // case the mating side will get a huge bonus at the end of the main - // evaluation function instead. - if (ei.mateThreat[Them] != MOVE_NONE) - attackUnits += MateThreatBonus; - - // Ensure that attackUnits is between 0 and 99, in order to avoid array - // out of bounds errors. - attackUnits = Min(99, Max(0, attackUnits)); - - // Finally, extract the king safety score from the SafetyTable[] array. - // Add the score to the evaluation, and also to ei.futilityMargin. The - // reason for adding the king safety score to the futility margin is - // that the king safety scores can sometimes be very big, and that - // capturing a single attacking piece can therefore result in a score - // change far bigger than the value of the captured piece. - Score v = apply_weight(make_score(SafetyTable[attackUnits], 0), WeightKingSafety[Us]); - ei.value -= Sign[Us] * v; - ei.futilityMargin[Us] += mg_value(v); - } + return score; } // evaluate_passed_pawns() evaluates the passed pawns of the given color - template - void evaluate_passed_pawns_of_color(const Position& pos, int movesToGo[], Square pawnToGo[], EvalInfo& ei) { + template + Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); - 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); + Bitboard b, squaresToQueen, defendedSquares, unsafeSquares; + Score score = SCORE_ZERO; + + b = ei.pi->passed_pawns(Us); while (b) { - Square s = pop_1st_bit(&b); + Square s = pop_lsb(&b); - assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN)); - assert(pos.pawn_is_passed(Us, s)); + assert(pos.pawn_passed(Us, s)); - int r = int(relative_rank(Us, s) - RANK_2); - int tr = Max(0, r * (r - 1)); + int r = relative_rank(Us, s) - RANK_2; + int rr = r * (r - 1); - // Base bonus based on rank - Value mbonus = Value(20 * tr); - Value ebonus = Value(10 + r * r * 10); + Value mbonus = Passed[MG][r], ebonus = Passed[EG][r]; - // Adjust bonus based on king proximity - if (tr) + if (rr) { 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); - - // If the pawn is free to advance, increase bonus - if (pos.square_is_empty(blockSq)) - { - // There are no enemy pawns in the pawn's path - b2 = squares_in_front_of(Us, s); - - assert((b2 & pos.pieces(PAWN, Them)) == EmptyBoardBB); - - // Squares attacked by us - b4 = b2 & ei.attacked_by(Us); - - // Squares attacked or occupied by enemy pieces - b3 = b2 & (ei.attacked_by(Them) | pos.pieces_of_color(Them)); - - // 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; - - // 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); - } - } // 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; + // Adjust bonus based on the king's proximity + ebonus += distance(pos.square(Them), blockSq) * 5 * rr + - distance(pos.square(Us ), blockSq) * 2 * rr; - 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 blockSq is not the queening square then consider also a second push + if (relative_rank(Us, blockSq) != RANK_8) + ebonus -= distance(pos.square(Us), blockSq + pawn_push(Us)) * rr; - if (d < 0) + // If the pawn is free to advance, then increase the bonus + if (pos.empty(blockSq)) { - 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; - } - } - } + // If there is a rook or queen attacking/defending the pawn from behind, + // consider all the squaresToQueen. Otherwise consider only the squares + // in the pawn's path attacked or occupied by the enemy. + defendedSquares = unsafeSquares = squaresToQueen = forward_bb(Us, s); - // 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; - } + Bitboard bb = forward_bb(Them, s) & pos.pieces(ROOK, QUEEN) & pos.attacks_from(s); - // Add the scores for this pawn to the middle game and endgame eval. - ei.value += Sign[Us] * apply_weight(make_score(mbonus, ebonus), WeightPassedPawns); - - } // while - } + if (!(pos.pieces(Us) & bb)) + defendedSquares &= ei.attackedBy[Us][ALL_PIECES]; + if (!(pos.pieces(Them) & bb)) + unsafeSquares &= ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them); - // evaluate_passed_pawns() evaluates the passed pawns for both sides + // 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 ? 18 : !(unsafeSquares & blockSq) ? 8 : 0; - void evaluate_passed_pawns(const Position& pos, EvalInfo& ei) { + // If the path to the queen is fully defended, assign a big bonus. + // Otherwise assign a smaller bonus if the block square is defended. + if (defendedSquares == squaresToQueen) + k += 6; - int movesToGo[2] = {0, 0}; - Square pawnToGo[2] = {SQ_NONE, SQ_NONE}; + else if (defendedSquares & blockSq) + k += 4; - // Evaluate pawns for each color - evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); - evaluate_passed_pawns_of_color(pos, movesToGo, pawnToGo, ei); + mbonus += k * rr, ebonus += k * rr; + } + else if (pos.pieces(Us) & blockSq) + mbonus += rr + r * 2, ebonus += rr + r * 2; + } // rr != 0 - // Neither side has an unstoppable passed pawn? - if (!(movesToGo[WHITE] | movesToGo[BLACK])) - return; + if (pos.count(Us) < pos.count(Them)) + ebonus += ebonus / 4; - // Does only one side have an unstoppable passed pawn? - if (!movesToGo[WHITE] || !movesToGo[BLACK]) - { - Color winnerSide = movesToGo[WHITE] ? WHITE : BLACK; - ei.value += make_score(0, Sign[winnerSide] * (UnstoppablePawnValue - Value(0x40 * movesToGo[winnerSide]))); + score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; } - 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()]--; - - 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 += Sign[winnerSide] * make_score(0, 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)); + if (DoTrace) + Trace::add(PASSED, Us, score); - 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 += Sign[winnerSide] * make_score(0, UnstoppablePawnValue - Value(0x40 * (movesToGo[winnerSide]/2))); - } - } + // Add the scores to the middlegame and endgame eval + return score; } - // evaluate_trapped_bishop_a7h7() determines whether a bishop on a7/h7 - // (a2/h2 for black) is trapped by enemy pawns, and assigns a penalty - // if it is. + // evaluate_space() computes the space evaluation for a given side. The + // 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 multiplied by a weight. The aim is to + // improve play on game opening. + template + Score evaluate_space(const Position& pos, const EvalInfo& ei) { - void evaluate_trapped_bishop_a7h7(const Position& pos, Square s, Color us, 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); - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + // Find the safe squares for our pieces inside the area defined by + // 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 + & ~pos.pieces(Us, PAWN) + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); - Square b6 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B6 : SQ_G6); - Square b8 = relative_square(us, (square_file(s) == FILE_A) ? SQ_B8 : SQ_G8); + // Find all squares which are at most three squares behind some friendly pawn + Bitboard behind = pos.pieces(Us, PAWN); + behind |= (Us == WHITE ? behind >> 8 : behind << 8); + behind |= (Us == WHITE ? behind >> 16 : behind << 16); - if ( pos.piece_on(b6) == piece_of_color_and_type(opposite_color(us), PAWN) - && pos.see(s, b6) < 0 - && pos.see(s, b8) < 0) - { - ei.value -= Sign[us] * TrappedBishopA7H7Penalty; - } + // Since SpaceMask[Us] is fully on our half of the board... + assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); + + // ...count safe + (behind & safe) with a single popcount + 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 * 2 / 11, 0); } - // evaluate_trapped_bishop_a1h1() determines whether a bishop on a1/h1 - // (a8/h8 for black) is trapped by a friendly pawn on b2/g2 (b7/g7 for - // black), and assigns a penalty if it is. This pattern can obviously - // only occur in Chess960 games. + // 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) { - void evaluate_trapped_bishop_a1h1(const Position& pos, Square s, Color us, EvalInfo& ei) { + int kingDistance = distance(pos.square(WHITE), pos.square(BLACK)) + - distance(pos.square(WHITE), pos.square(BLACK)); + int pawns = pos.count(WHITE) + pos.count(BLACK); - Piece pawn = piece_of_color_and_type(us, PAWN); - Square b2, b3, c3; + // Compute the initiative bonus for the attacking side + int initiative = 8 * (asymmetry + kingDistance - 15) + 12 * pawns; - assert(Chess960); - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + // 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)); - if (square_file(s) == FILE_A) - { - b2 = relative_square(us, SQ_B2); - b3 = relative_square(us, SQ_B3); - c3 = relative_square(us, SQ_C3); - } - else - { - b2 = relative_square(us, SQ_G2); - b3 = relative_square(us, SQ_G3); - c3 = relative_square(us, SQ_F3); - } + return make_score(0, value); + } - if (pos.piece_on(b2) == pawn) - { - Score penalty; - if (!pos.square_is_empty(b3)) - penalty = 2 * TrappedBishopA1H1Penalty; - else if (pos.piece_on(c3) == pawn) - penalty = TrappedBishopA1H1Penalty; - else - penalty = TrappedBishopA1H1Penalty / 2; + // evaluate_scale_factor() computes the scale factor for the winning side + ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Value eg) { + + Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK; + ScaleFactor sf = ei.me->scale_factor(pos, strongSide); - ei.value -= Sign[us] * penalty; + // 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, it 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) <= 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_space() computes the space evaluation for a given side. The - // 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. - template - void evaluate_space(const Position& pos, EvalInfo& ei) { - const Color Them = (Us == WHITE ? BLACK : WHITE); +/// evaluate() is the main evaluation function. It returns a static evaluation +/// of the position from the point of view of the side to move. - // Find the safe squares for our pieces inside the area defined by - // SpaceMask[us]. A square is unsafe if it is attacked by an enemy - // pawn, or if it is undefended and attacked by an enemy piece. +template +Value Eval::evaluate(const Position& pos) { - Bitboard safeSquares = SpaceMask[Us] - & ~pos.pieces(PAWN, Us) - & ~ei.attacked_by(Them, PAWN) - & ~(~ei.attacked_by(Us) & ei.attacked_by(Them)); + assert(!pos.checkers()); - // Find all squares which are at most three squares behind some friendly - // pawn. - Bitboard behindFriendlyPawns = pos.pieces(PAWN, Us); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 8 : behindFriendlyPawns << 8); - behindFriendlyPawns |= (Us == WHITE ? behindFriendlyPawns >> 16 : behindFriendlyPawns << 16); + EvalInfo ei; + Score score, mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO }; - int space = count_1s_max_15(safeSquares) - + count_1s_max_15(behindFriendlyPawns & safeSquares); + // 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(); - ei.value += Sign[Us] * apply_weight(make_score(space * ei.mi->space_weight(), 0), WeightSpace); - } + // Probe the material hash table + ei.me = Material::probe(pos); + score += ei.me->imbalance(); + // If we have a specialized evaluation function for the current material + // configuration, call it and return. + if (ei.me->specialized_eval_exists()) + return ei.me->evaluate(pos); - // apply_weight() applies an evaluation weight to a value trying to prevent overflow + // Probe the pawn hash table + ei.pi = Pawns::probe(pos); + score += ei.pi->pawns_score(); + + // Initialize attack and king safety bitboards + ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; + eval_init(pos, ei); + eval_init(pos, ei); + + // 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) + }; - inline Score apply_weight(Score v, Score w) { - return make_score((int(mg_value(v)) * mg_value(w)) / 0x100, (int(eg_value(v)) * eg_value(w)) / 0x100); - } + // 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 all pieces but king and pawns + score += evaluate_pieces(pos, ei, mobility, mobilityArea); + score += mobility[WHITE] - mobility[BLACK]; - // 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. + // 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); - Value scale_by_game_phase(const Score& v, Phase ph, const ScaleFactor sf[]) { + // Evaluate tactical threats, we need full attack information including king + score += evaluate_threats(pos, ei) + - evaluate_threats(pos, ei); - assert(mg_value(v) > -VALUE_INFINITE && mg_value(v) < VALUE_INFINITE); - assert(eg_value(v) > -VALUE_INFINITE && eg_value(v) < VALUE_INFINITE); - assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); + // Evaluate passed pawns, we need full attack information including king + score += evaluate_passed_pawns(pos, ei) + - evaluate_passed_pawns(pos, ei); - Value ev = apply_scale_factor(eg_value(v), sf[(eg_value(v) > Value(0) ? WHITE : BLACK)]); + // If both sides have only pawns, score for potential unstoppable pawns + if (!pos.non_pawn_material(WHITE) && !pos.non_pawn_material(BLACK)) + { + Bitboard b; + if ((b = ei.pi->passed_pawns(WHITE)) != 0) + score += Unstoppable * int(relative_rank(WHITE, frontmost_sq(WHITE, b))); - int result = (mg_value(v) * ph + ev * (128 - ph)) / 128; - return Value(result & ~(GrainSize - 1)); + if ((b = ei.pi->passed_pawns(BLACK)) != 0) + score -= Unstoppable * int(relative_rank(BLACK, frontmost_sq(BLACK, b))); } + // Evaluate space for both sides, only during opening + if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222) + score += evaluate_space(pos, ei) + - evaluate_space(pos, ei); - // weight_option() computes the value of an evaluation weight, by combining - // two UCI-configurable weights (midgame and endgame) with an internal weight. + // Evaluate position potential for the winning side + score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score)); - Score weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { + // Evaluate scale factor for the winning side + ScaleFactor sf = evaluate_scale_factor(pos, ei, eg_value(score)); - Score uciWeight = make_score(get_option_value_int(mgOpt), get_option_value_int(egOpt)); + // Interpolate between a middlegame and a (scaled by 'sf') endgame score + Value v = mg_value(score) * int(ei.me->game_phase()) + + eg_value(score) * int(PHASE_MIDGAME - ei.me->game_phase()) * sf / SCALE_FACTOR_NORMAL; - // Convert to integer to prevent overflow - int mg = mg_value(uciWeight); - int eg = eg_value(uciWeight); + v /= int(PHASE_MIDGAME); - mg = (mg * 0x100) / 100; - eg = (eg * 0x100) / 100; - mg = (mg * mg_value(internalWeight)) / 0x100; - eg = (eg * eg_value(internalWeight)) / 0x100; - return make_score(mg, eg); + // In case of tracing add all remaining individual evaluation terms + if (DoTrace) + { + Trace::add(MATERIAL, pos.psq_score()); + Trace::add(IMBALANCE, ei.me->imbalance()); + Trace::add(PAWN, ei.pi->pawns_score()); + Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); + Trace::add(SPACE, evaluate_space(pos, ei) + , evaluate_space(pos, ei)); + Trace::add(TOTAL, score); } - // init_safety() initizes the king safety evaluation, based on UCI - // parameters. It is called from read_weights(). + return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; // Side to move point of view +} - void init_safety() { +// Explicit template instantiations +template Value Eval::evaluate(const Position&); +template Value Eval::evaluate(const Position&); + + +/// trace() is like evaluate(), but instead of returning a value, it returns +/// a string (suitable for outputting to stdout) that contains the detailed +/// descriptions and values of each evaluation term. Useful for debugging. + +std::string Eval::trace(const Position& pos) { + + std::memset(scores, 0, sizeof(scores)); + + Value v = evaluate(pos); + v = pos.side_to_move() == WHITE ? v : -v; // White's point of view + + std::stringstream ss; + ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2) + << " Eval term | White | Black | Total \n" + << " | MG EG | MG EG | MG EG \n" + << "----------------+-------------+-------------+-------------\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"; + + return ss.str(); +} - QueenContactCheckBonus = get_option_value_int("Queen Contact Check Bonus"); - QueenCheckBonus = get_option_value_int("Queen Check Bonus"); - RookCheckBonus = get_option_value_int("Rook Check Bonus"); - BishopCheckBonus = get_option_value_int("Bishop Check Bonus"); - KnightCheckBonus = get_option_value_int("Knight Check Bonus"); - DiscoveredCheckBonus = get_option_value_int("Discovered Check Bonus"); - MateThreatBonus = get_option_value_int("Mate Threat Bonus"); - int maxSlope = get_option_value_int("King Safety Max Slope"); - int peak = get_option_value_int("King Safety Max Value") * 256 / 100; - double a = get_option_value_int("King Safety Coefficient") / 100.0; - double b = get_option_value_int("King Safety X Intercept"); - bool quad = (get_option_value_string("King Safety Curve") == "Quadratic"); - bool linear = (get_option_value_string("King Safety Curve") == "Linear"); +/// init() computes evaluation weights, usually at startup - for (int i = 0; i < 100; i++) - { - if (i < b) - SafetyTable[i] = Value(0); - else if (quad) - SafetyTable[i] = Value((int)(a * (i - b) * (i - b))); - else if (linear) - SafetyTable[i] = Value((int)(100 * a * (i - b))); - } +void Eval::init() { - for (int i = 0; i < 100; i++) - { - if (SafetyTable[i+1] - SafetyTable[i] > maxSlope) - for (int j = i + 1; j < 100; j++) - SafetyTable[j] = SafetyTable[j-1] + Value(maxSlope); + const int MaxSlope = 322; + const int Peak = 47410; + int t = 0; - if (SafetyTable[i] > Value(peak)) - SafetyTable[i] = Value(peak); - } + for (int i = 0; i < 400; ++i) + { + t = std::min(Peak, std::min(i * i - 16, t + MaxSlope)); + KingDanger[i] = make_score(t * 268 / 7700, 0); } }