X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fevaluate.cpp;h=d7b83057ff7c2ddb5108f708faed601ae12dd407;hb=d3ffd0ffcad5e467fffd67d82d031fa1cbdba7d2;hp=a291ec466258b0bb336850e3444cffbccb4bc6f0;hpb=17c511922277e49eacdede3c92491ee32c303c30;p=stockfish diff --git a/src/evaluate.cpp b/src/evaluate.cpp index a291ec46..be53a73e 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2009 Marco Costalba + Copyright (C) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,40 +17,84 @@ along with this program. If not, see . */ - -//// -//// Includes -//// - #include -#include +#include +#include +#include #include "bitcount.h" #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "scale.h" #include "thread.h" #include "ucioption.h" +namespace { -//// -//// Local definitions -//// + // Struct EvalInfo contains various information computed and collected + // by the evaluation functions. + struct EvalInfo { + + // Pointers to material and pawn hash table entries + Material::Entry* mi; + Pawns::Entry* pi; + + // attackedBy[color][piece type] is a bitboard representing all squares + // attacked by a given color and piece type, attackedBy[color][ALL_PIECES] + // contains all squares attacked by the given color. + 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 "weight" of the pieces of the + // given color which attack a square in the kingRing of the enemy king. The + // weights of the individual piece types are given by the variables + // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and + // KnightAttackWeight in evaluate.cpp + int kingAttackersWeight[COLOR_NB]; + + // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares + // directly adjacent to the king of the given color. Pieces which attack + // more than one square are counted multiple times. For instance, if black's + // king is on g8 and there's a white knight on g5, this knight adds + // 2 to kingAdjacentZoneAttacksCount[BLACK]. + int kingAdjacentZoneAttacksCount[COLOR_NB]; + + Bitboard pinnedPieces[COLOR_NB]; + }; -namespace { + namespace Tracing { + + enum Terms { // First 8 entries are for PieceType + PST = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERMS_NB + }; - const int Sign[2] = { 1, -1 }; + Score terms[COLOR_NB][TERMS_NB]; + EvalInfo ei; + ScaleFactor sf; - // Evaluation grain size, must be a power of 2 - const int GrainSize = 4; + double to_cp(Value v); + void add_term(int idx, Score term_w, Score term_b = SCORE_ZERO); + void format_row(std::stringstream& ss, const char* name, int idx); + std::string do_trace(const Position& pos); + } // Evaluation weights, initialized from UCI options - int WeightMobilityMidgame, WeightMobilityEndgame; - int WeightPawnStructureMidgame, WeightPawnStructureEndgame; - int WeightPassedPawnsMidgame, WeightPassedPawnsEndgame; - int WeightKingSafety[2]; - int WeightSpace; + enum { Mobility, PawnStructure, PassedPawns, Space, KingDangerUs, KingDangerThem }; + struct Weight { int mg, eg; } Weights[6]; + + typedef Value V; + #define S(mg, eg) make_score(mg, eg) // Internal evaluation weights. These are applied on top of the evaluation // weights read from UCI parameters. The purpose is to be able to change @@ -58,1167 +102,827 @@ namespace { // parameters at 100, which looks prettier. // // Values modified by Joona Kiiski - const int WeightMobilityMidgameInternal = 248; - const int WeightMobilityEndgameInternal = 271; - const int WeightPawnStructureMidgameInternal = 233; - const int WeightPawnStructureEndgameInternal = 201; - const int WeightPassedPawnsMidgameInternal = 252; - const int WeightPassedPawnsEndgameInternal = 259; - const int WeightKingSafetyInternal = 247; - const int WeightKingOppSafetyInternal = 259; - const int WeightSpaceInternal = 46; - - // Mobility and outposts bonus modified by Joona Kiiski - // - // Visually better to define tables constants - typedef Value V; - - // Knight mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly piecess. - const Value MidgameKnightMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 8 - V(-38), V(-25),V(-12), V(0), V(12), V(25), V(31), V(38), V(38) + const Score WeightsInternal[] = { + S(289, 344), S(233, 201), S(221, 273), S(46, 0), S(271, 0), S(307, 0) }; - const Value EndgameKnightMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 8 - V(-33), V(-23),V(-13), V(-3), V(7), V(17), V(22), V(27), V(27) + // MobilityBonus[PieceType][attacked] contains bonuses for middle and end + // game, indexed by piece type and number of attacked squares not occupied by + // friendly pieces. + const Score MobilityBonus[][32] = { + {}, {}, + { S(-65,-50), S(-42,-30), S(-9,-10), S( 3, 0), S(15, 10), S(27, 20), // Knights + S( 37, 28), S( 42, 31), S(44, 33) }, + { S(-52,-47), S(-28,-23), S( 6, 1), S(20, 15), S(34, 29), S(48, 43), // Bishops + S( 60, 55), S( 68, 63), S(74, 68), S(77, 72), S(80, 75), S(82, 77), + S( 84, 79), S( 86, 81) }, + { S(-47,-53), S(-31,-26), S(-5, 0), S( 1, 16), S( 7, 32), S(13, 48), // Rooks + S( 18, 64), S( 22, 80), S(26, 96), S(29,109), S(31,115), S(33,119), + S( 35,122), S( 36,123), S(37,124) }, + { S(-42,-40), S(-28,-23), S(-5, -7), S( 0, 0), S( 6, 10), S(11, 19), // Queens + S( 13, 29), S( 18, 38), S(20, 40), S(21, 41), S(22, 41), S(22, 41), + S( 22, 41), S( 23, 41), S(24, 41), S(25, 41), S(25, 41), S(25, 41), + S( 25, 41), S( 25, 41), S(25, 41), S(25, 41), S(25, 41), S(25, 41), + S( 25, 41), S( 25, 41), S(25, 41), S(25, 41) } }; - // 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 Value MidgameBishopMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-25), V(-11), V(3), V(17), V(31), V(45), V(57), V(65), - // 8 9 10 11 12 13 14 15 - V( 71), V( 74), V(76), V(78), V(79), V(80), V(81), V(81) - }; - - const Value EndgameBishopMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-30), V(-16), V(-2), V(12), V(26), V(40), V(52), V(60), - // 8 9 10 11 12 13 14 15 - V( 65), V( 69), V(71), V(73), V(74), V(75), V(76), V(76) - }; - - // 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 Value MidgameRookMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-20), V(-14), V(-8), V(-2), V(4), V(10), V(14), V(19), - // 8 9 10 11 12 13 14 15 - V( 23), V( 26), V(27), V(28), V(29), V(30), V(31), V(32) - }; - - const Value EndgameRookMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-36), V(-19), V(-3), V(13), V(29), V(46), V(62), V(79), - // 8 9 10 11 12 13 14 15 - V( 95), V(106),V(111),V(114),V(116),V(117),V(118),V(118) - }; - - // Queen mobility bonus in middle game and endgame, indexed by the number - // of attacked squares not occupied by friendly pieces. - const Value MidgameQueenMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-10), V(-8), V(-6), V(-3), V(-1), V( 1), V( 3), V( 5), - // 8 9 10 11 12 13 14 15 - V( 8), V(10), V(12), V(15), V(16), V(17), V(18), V(20), - // 16 17 18 19 20 21 22 23 - V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20), - // 24 25 26 27 28 29 30 31 - V( 20), V(20), V(20), V(20), V(20), V(20), V(20), V(20) - }; - - const Value EndgameQueenMobilityBonus[] = { - // 0 1 2 3 4 5 6 7 - V(-18),V(-13), V(-7), V(-2), V( 3), V (8), V(13), V(19), - // 8 9 10 11 12 13 14 15 - V( 23), V(27), V(32), V(34), V(35), V(35), V(35), V(35), - // 16 17 18 19 20 21 22 23 - V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35), - // 24 25 26 27 28 29 30 31 - V( 35), V(35), V(35), V(35), V(35), V(35), V(35), V(35) + // Outpost[PieceType][Square] contains bonuses for knights and bishops outposts, + // indexed by piece type and square (from white's point of view). + const Value Outpost[][SQUARE_NB] = { + {// A B C D E F G H + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Knights + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), + V(0), V(0), V(4), V(8), V(8), V(4), V(0), V(0), + V(0), V(4),V(17),V(26),V(26),V(17), V(4), V(0), + V(0), V(8),V(26),V(35),V(35),V(26), V(8), V(0), + V(0), V(4),V(17),V(17),V(17),V(17), V(4), V(0) }, + { + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), // Bishops + V(0), V(0), V(0), V(0), V(0), V(0), V(0), V(0), + V(0), V(0), V(5), V(5), V(5), V(5), V(0), V(0), + V(0), V(5),V(10),V(10),V(10),V(10), V(5), V(0), + V(0),V(10),V(21),V(21),V(21),V(21),V(10), V(0), + V(0), V(5), V(8), V(8), V(8), V(8), V(5), V(0) } }; - // Outpost 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 + // Threat[attacking][attacked] contains bonuses according to which piece + // type attacks which one. + const Score Threat[][PIECE_TYPE_NB] = { + { S(0, 0), S( 7, 39), S(24, 49), S(24, 49), S(41,100), S(41,100) }, // Minor + { S(0, 0), S(15, 39), S(15, 45), S(15, 45), S(15, 45), S(24, 49) } // Major }; - 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 + // ThreatenedByPawn[PieceType] contains a penalty according to which piece + // type is attacked by an enemy pawn. + const Score ThreatenedByPawn[] = { + S(0, 0), S(0, 0), S(56, 70), S(56, 70), S(76, 99), S(86, 118) }; - // Bonus for unstoppable passed pawns - const Value UnstoppablePawnValue = Value(0x500); - - // Rooks and queens on the 7th rank (modified by Joona Kiiski) - const Value MidgameRookOn7thBonus = Value(47); - const Value EndgameRookOn7thBonus = Value(98); - const Value MidgameQueenOn7thBonus = Value(27); - const Value EndgameQueenOn7thBonus = Value(54); - - // Rooks on open files (modified by Joona Kiiski) - const Value RookOpenFileBonus = Value(43); - const Value RookHalfOpenFileBonus = Value(19); + // Hanging[side to move] contains a bonus for each enemy hanging piece + const Score Hanging[2] = { S(23, 20) , S(35, 45) }; - // Penalty for rooks trapped inside a friendly king which has lost the - // right to castle. - const Value TrappedRookPenalty = Value(180); + #undef S - // Penalty for a bishop on a7/h7 (a2/h2 for black) which is trapped by - // enemy pawns. - const Value TrappedBishopA7H7Penalty = Value(300); - - // 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)) - }; + const Score Tempo = make_score(24, 11); + const Score RookOnPawn = make_score(10, 28); + const Score RookOpenFile = make_score(43, 21); + const Score RookSemiopenFile = make_score(19, 10); + const Score BishopPawns = make_score( 8, 12); + const Score MinorBehindPawn = make_score(16, 0); + const Score UndefendedMinor = make_score(25, 10); + const Score TrappedRook = make_score(90, 0); + const Score Unstoppable = make_score( 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 Value TrappedBishopA1H1Penalty = Value(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)) - }; + const Score TrappedBishopA1H1 = make_score(50, 50); - // 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 + // SpaceMask[Color] contains the area of the board which is considered + // by the space evaluation. In the middlegame, each side is given a bonus // based on how many squares inside this area are safe and available for // friendly minor pieces. - const Bitboard SpaceMask[2] = { - (1ULL< - Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID); + // apply_weight() weighs score 'v' by weight 'w' trying to prevent overflow + Score apply_weight(Score v, const Weight& w) { + return make_score(mg_value(v) * w.mg / 256, eg_value(v) * w.eg / 256); + } - template - void evaluate_pieces(const Position& p, Color us, EvalInfo& ei); - template - void evaluate_king(const Position& p, Color us, EvalInfo &ei); + // weight_option() computes the value of an evaluation weight, by combining + // two UCI-configurable weights (midgame and endgame) with an internal weight. - 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); - template - void evaluate_space(const Position &p, 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[]); + Weight weight_option(const std::string& mgOpt, const std::string& egOpt, Score internalWeight) { - int compute_weight(int uciWeight, int internalWeight); - int weight_option(const std::string& opt, int weight); - void init_safety(); + Weight w = { Options[mgOpt] * mg_value(internalWeight) / 100, + Options[egOpt] * eg_value(internalWeight) / 100 }; + return w; + } -} + // init_eval_info() initializes king bitboards for given color adding + // pawn attacks. To be done at the beginning of the evaluation. -//// -//// Functions -//// + template + void init_eval_info(const Position& pos, EvalInfo& ei) { -/// 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) { + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); - return CpuHasPOPCNT ? do_evaluate(pos, ei, threadID) - : do_evaluate(pos, ei, threadID); -} + ei.pinnedPieces[Us] = pos.pinned_pieces(Us); -namespace { + Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from(pos.king_square(Them)); + ei.attackedBy[Us][ALL_PIECES] = ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us); -template -Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) { - - assert(pos.is_ok()); - assert(threadID >= 0 && threadID < THREAD_MAX); - - 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(); - - // 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(); - - // 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.mgValue += apply_weight(ei.pi->mg_value(), WeightPawnStructureMidgame); - ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame); - - // Initialize king attack bitboards and king attack zones for both sides - ei.attackedBy[WHITE][KING] = pos.piece_attacks(pos.king_square(WHITE)); - ei.attackedBy[BLACK][KING] = pos.piece_attacks(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] = ((pos.pawns(WHITE) << 9) & ~FileABB) | ((pos.pawns(WHITE) << 7) & ~FileHBB); - ei.attackedBy[BLACK][PAWN] = ((pos.pawns(BLACK) >> 7) & ~FileABB) | ((pos.pawns(BLACK) >> 9) & ~FileHBB); - 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 - for (Color c = WHITE; c <= BLACK; c++) - { - evaluate_pieces(pos, c, ei); - evaluate_pieces(pos, c, ei); - evaluate_pieces(pos, c, ei); - evaluate_pieces(pos, c, ei); - - // Sum up all attacked squares - ei.attackedBy[c][0] = ei.attackedBy[c][PAWN] | ei.attackedBy[c][KNIGHT] - | ei.attackedBy[c][BISHOP] | ei.attackedBy[c][ROOK] - | ei.attackedBy[c][QUEEN] | ei.attackedBy[c][KING]; + // Init king safety tables only if we are going to use them + if (pos.count(Us) && pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg) + { + 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; } - // 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. - for (Color c = WHITE; c <= BLACK; c++) - evaluate_king(pos, c, 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. - if (ei.pi->passed_pawns()) - evaluate_passed_pawns(pos, ei); - Phase phase = pos.game_phase(); + // evaluate_outposts() evaluates bishop and knight outpost squares - // 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) + template + Score evaluate_outposts(const Position& pos, EvalInfo& ei, Square s) { - ei.mgValue += ei.pi->queenside_storm_value(WHITE) - - ei.pi->kingside_storm_value(BLACK); + const Color Them = (Us == WHITE ? BLACK : WHITE); - else if ( square_file(pos.king_square(WHITE)) <= FILE_D - && square_file(pos.king_square(BLACK)) >= FILE_E) + assert (Pt == BISHOP || Pt == KNIGHT); - ei.mgValue += ei.pi->kingside_storm_value(WHITE) - - ei.pi->queenside_storm_value(BLACK); + // Initial bonus based on square + Value bonus = Outpost[Pt == BISHOP][relative_square(Us, s)]; - // Evaluate space for both sides - if (ei.mi->space_weight() > 0) + // Increase bonus if supported by pawn, especially if the opponent has + // no minor piece which can trade with the outpost piece. + if (bonus && (ei.attackedBy[Us][PAWN] & s)) { - evaluate_space(pos, WHITE, ei); - evaluate_space(pos, BLACK, ei); + if ( !pos.pieces(Them, KNIGHT) + && !(squares_of_color(s) & pos.pieces(Them, BISHOP))) + bonus += bonus + bonus / 2; + else + bonus += bonus / 2; } + + return make_score(bonus, bonus); } - // Mobility - ei.mgValue += apply_weight(ei.mgMobility, WeightMobilityMidgame); - ei.egValue += apply_weight(ei.egMobility, 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)))) - { - 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 + + template + Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, Bitboard* mobilityArea) { - // Interpolate between the middle game and the endgame score, and - // return - Color stm = pos.side_to_move(); + Bitboard b; + Square s; + Score score = SCORE_ZERO; - Value v = Sign[stm] * scale_by_game_phase(ei.mgValue, ei.egValue, phase, factor); + const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); + const Color Them = (Us == WHITE ? BLACK : WHITE); + const Square* pl = pos.list(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); -/// quick_evaluate() does a very approximate evaluation of the current position. -/// It currently considers only material and piece square table scores. Perhaps -/// we should add scores from the pawn and material hash tables? + if (ei.pinnedPieces[Us] & s) + b &= LineBB[pos.king_square(Us)][s]; -Value quick_evaluate(const Position &pos) { + ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; - assert(pos.is_ok()); + if (b & ei.kingRing[Them]) + { + ei.kingAttackersCount[Us]++; + ei.kingAttackersWeight[Us] += KingAttackWeights[Pt]; + Bitboard bb = b & ei.attackedBy[Them][KING]; + if (bb) + ei.kingAdjacentZoneAttacksCount[Us] += popcount(bb); + } - static const - ScaleFactor sf[2] = {SCALE_FACTOR_NORMAL, SCALE_FACTOR_NORMAL}; + if (Pt == QUEEN) + b &= ~( ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] + | ei.attackedBy[Them][ROOK]); - Value mgv = pos.mg_value(); - Value egv = pos.eg_value(); - Phase ph = pos.game_phase(); - Color stm = pos.side_to_move(); + int mob = Pt != QUEEN ? popcount(b & mobilityArea[Us]) + : popcount(b & mobilityArea[Us]); - return Sign[stm] * scale_by_game_phase(mgv, egv, ph, sf); -} + mobility[Us] += MobilityBonus[Pt][mob]; + // Decrease score if we are attacked by an enemy pawn. The remaining part + // of threat evaluation must be done later when we have full attack info. + if (ei.attackedBy[Them][PAWN] & s) + score -= ThreatenedByPawn[Pt]; -/// init_eval() initializes various tables used by the evaluation function. + if (Pt == BISHOP || Pt == KNIGHT) + { + // Penalty for bishop with same colored pawns + if (Pt == BISHOP) + score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s); + + // Bishop and knight outposts squares + if (!(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) + score += evaluate_outposts(pos, ei, s); + + // Bishop or knight behind a pawn + if ( relative_rank(Us, s) < RANK_5 + && (pos.pieces(PAWN) & (s + pawn_push(Us)))) + score += MinorBehindPawn; + } -void init_eval(int threads) { + if (Pt == ROOK) + { + // Rook piece attacking enemy pawns on the same rank/file + if (relative_rank(Us, s) >= RANK_5) + { + Bitboard pawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; + if (pawns) + score += popcount(pawns) * RookOnPawn; + } - assert(threads <= THREAD_MAX); + // Give a bonus for a rook on a open or semi-open file + if (ei.pi->semiopen_file(Us, file_of(s))) + score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOpenFile : RookSemiopenFile; - for (int i = 0; i < THREAD_MAX; i++) - { - if (i >= threads) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - continue; + if (mob > 3 || ei.pi->semiopen_file(Us, file_of(s))) + continue; + + Square ksq = pos.king_square(Us); + + // Penalize rooks which are trapped by a king. Penalize more if the + // king has lost its castling capability. + if ( ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq))) + && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1) + && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq))) + score -= (TrappedRook - make_score(mob * 8, 0)) * (1 + !pos.can_castle(Us)); + } + + // An important Chess960 pattern: A cornered bishop blocked by a friendly + // pawn diagonally in front of it is a very serious problem, especially + // when that pawn is also blocked. + if ( Pt == BISHOP + && pos.is_chess960() + && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1))) + { + Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W); + if (pos.piece_on(s + d) == make_piece(Us, PAWN)) + score -= !pos.empty(s + d + pawn_push(Us)) ? TrappedBishopA1H1 * 4 + : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2 + : TrappedBishopA1H1; + } } - if (!PawnTable[i]) - PawnTable[i] = new PawnInfoTable(PawnTableSize); - if (!MaterialTable[i]) - MaterialTable[i] = new MaterialInfoTable(MaterialTableSize); + + if (Trace) + Tracing::terms[Us][Pt] = score; + + return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } -} + template<> + Score evaluate_pieces(const Position&, EvalInfo&, Score*, Bitboard*) { return SCORE_ZERO; } + template<> + Score evaluate_pieces(const Position&, EvalInfo&, Score*, Bitboard*) { return SCORE_ZERO; } -/// quit_eval() releases heap-allocated memory at program termination. -void quit_eval() { + // evaluate_king() assigns bonuses and penalties to a king of a given color - for (int i = 0; i < THREAD_MAX; i++) - { - delete PawnTable[i]; - delete MaterialTable[i]; - PawnTable[i] = NULL; - MaterialTable[i] = NULL; - } -} + template + Score evaluate_king(const Position& pos, const EvalInfo& ei) { + const Color Them = (Us == WHITE ? BLACK : WHITE); -/// read_weights() reads evaluation weights from the corresponding UCI -/// parameters. + Bitboard undefended, b, b1, b2, safe; + int attackUnits; + const Square ksq = pos.king_square(Us); -void read_weights(Color us) { + // King shelter and enemy pawns storm + Score score = ei.pi->king_safety(pos, ksq); - WeightMobilityMidgame = weight_option("Mobility (Middle Game)", WeightMobilityMidgameInternal); - WeightMobilityEndgame = weight_option("Mobility (Endgame)", WeightMobilityEndgameInternal); - WeightPawnStructureMidgame = weight_option("Pawn Structure (Middle Game)", WeightPawnStructureMidgameInternal); - WeightPawnStructureEndgame = weight_option("Pawn Structure (Endgame)", WeightPawnStructureEndgameInternal); - WeightPassedPawnsMidgame = weight_option("Passed Pawns (Middle Game)", WeightPassedPawnsMidgameInternal); - WeightPassedPawnsEndgame = weight_option("Passed Pawns (Endgame)", WeightPassedPawnsEndgameInternal); + // Main king safety evaluation + if (ei.kingAttackersCount[Them]) + { + // 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 to the KingDanger[] array. The initial value is based on the + // number and types of the enemy's attacking pieces, the number of + // attacked and undefended squares around our king and the quality of + // the pawn shelter (current 'score' value). + attackUnits = std::min(20, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) + + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount(undefended)) + + 2 * (ei.pinnedPieces[Us] != 0) + - mg_value(score) / 32; + + // Analyse the enemy's safe queen contact checks. Firstly, find the + // undefended squares around the king that are attacked by the enemy's + // queen... + b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them); + if (b) + { + // ...and then remove squares not supported by another enemy piece + b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); + + if (b) + attackUnits += QueenContactCheck + * popcount(b) + * (Them == pos.side_to_move() ? 2 : 1); + } - Color them = opposite_color(us); + // Analyse the enemy's safe rook contact checks. Firstly, find the + // undefended squares around the king that are attacked by the enemy's + // rooks... + b = undefended & ei.attackedBy[Them][ROOK] & ~pos.pieces(Them); - WeightKingSafety[us] = weight_option("Cowardice", WeightKingSafetyInternal); - WeightKingSafety[them] = weight_option("Aggressiveness", WeightKingOppSafetyInternal); - // 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]; - } + // Consider only squares where the enemy's rook gives check + b &= PseudoAttacks[ROOK][ksq]; - WeightSpace = weight_option("Space", WeightSpaceInternal); + if (b) + { + // ...and then remove squares not supported by another enemy piece + b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]); + + if (b) + attackUnits += RookContactCheck + * popcount(b) + * (Them == pos.side_to_move() ? 2 : 1); + } - init_safety(); -} + // Analyse the enemy's safe distance checks for sliders and knights + safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]); + b1 = pos.attacks_from(ksq) & safe; + b2 = pos.attacks_from(ksq) & safe; -namespace { + // Enemy queen safe checks + b = (b1 | b2) & ei.attackedBy[Them][QUEEN]; + if (b) + attackUnits += QueenCheck * popcount(b); - // evaluate_mobility() computes mobility and attacks for every piece + // Enemy rooks safe checks + b = b1 & ei.attackedBy[Them][ROOK]; + if (b) + attackUnits += RookCheck * popcount(b); - template - int evaluate_mobility(const Position& p, const Bitboard& b, Color us, Color them, EvalInfo& ei) { + // Enemy bishops safe checks + b = b2 & ei.attackedBy[Them][BISHOP]; + if (b) + attackUnits += BishopCheck * popcount(b); - static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight }; - static const Value* MgBonus[] = { 0, 0, MidgameKnightMobilityBonus, MidgameBishopMobilityBonus, MidgameRookMobilityBonus, MidgameQueenMobilityBonus }; - static const Value* EgBonus[] = { 0, 0, EndgameKnightMobilityBonus, EndgameBishopMobilityBonus, EndgameRookMobilityBonus, EndgameQueenMobilityBonus }; + // Enemy knights safe checks + b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe; + if (b) + attackUnits += KnightCheck * popcount(b); - // Update attack info - ei.attackedBy[us][Piece] |= b; + // To index KingDanger[] attackUnits must be in [0, 99] range + attackUnits = std::min(99, std::max(0, attackUnits)); - // King attacks - if (b & ei.kingZone[us]) - { - 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); + // Finally, extract the king danger score from the KingDanger[] + // array and subtract the score from evaluation. + score -= KingDanger[Us == Search::RootColor][attackUnits]; } - // Remove squares protected by enemy pawns - Bitboard bb = (b & ~ei.attackedBy[them][PAWN]); + if (Trace) + Tracing::terms[Us][KING] = score; - // Mobility - int mob = (Piece != QUEEN ? count_1s_max_15(bb & ~p.pieces_of_color(us)) - : count_1s(bb & ~p.pieces_of_color(us))); - - ei.mgMobility += Sign[us] * MgBonus[Piece][mob]; - ei.egMobility += Sign[us] * EgBonus[Piece][mob]; - return mob; + return score; } - // evaluate_outposts() evaluates bishop and knight outposts squares + // evaluate_threats() assigns bonuses according to the type of attacking piece + // and the type of attacked one. - template - void evaluate_outposts(const Position& p, Color us, Color them, EvalInfo& ei, Square s) { + template + Score evaluate_threats(const Position& pos, const EvalInfo& ei) { - // Initial bonus based on square - Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(us, s)] - : KnightOutpostBonus[relative_square(us, s)]); + const Color Them = (Us == WHITE ? BLACK : WHITE); - // Increase bonus if supported by pawn, especially if the opponent has - // no minor piece which can exchange the outpost piece - if (bonus && (p.pawn_attacks(them, s) & p.pawns(us))) + Bitboard b, undefendedMinors, weakEnemies; + Score score = SCORE_ZERO; + + // Undefended minors get penalized even if they are not under attack + undefendedMinors = pos.pieces(Them, BISHOP, KNIGHT) + & ~ei.attackedBy[Them][ALL_PIECES]; + + if (undefendedMinors) + score += UndefendedMinor; + + // Enemies not defended by a pawn and under our attack + weakEnemies = pos.pieces(Them) + & ~ei.attackedBy[Them][PAWN] + & ei.attackedBy[Us][ALL_PIECES]; + + // Add a bonus according if the attacking pieces are minor or major + if (weakEnemies) { - if ( p.knights(them) == EmptyBoardBB - && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB) - bonus += bonus + bonus / 2; - else - bonus += bonus / 2; + b = weakEnemies & (ei.attackedBy[Us][PAWN] | ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + if (b) + score += Threat[0][type_of(pos.piece_on(lsb(b)))]; + + b = weakEnemies & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); + if (b) + score += Threat[1][type_of(pos.piece_on(lsb(b)))]; + + b = weakEnemies & ~ei.attackedBy[Them][ALL_PIECES]; + if (b) + score += more_than_one(b) ? Hanging[Us != pos.side_to_move()] * popcount(b) + : Hanging[Us == pos.side_to_move()]; } - ei.mgValue += Sign[us] * bonus; - ei.egValue += Sign[us] * bonus; + + if (Trace) + Tracing::terms[Us][Tracing::THREAT] = score; + + return score; } - // evaluate_pieces<>() assigns bonuses and penalties to the pieces of a given - // color. + // evaluate_passed_pawns() evaluates the passed pawns of the given color - template - void evaluate_pieces(const Position& pos, Color us, EvalInfo& ei) { + template + Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei) { - Bitboard b; - Square s, ksq; - int mob; - File f; - Color them = opposite_color(us); + const Color Them = (Us == WHITE ? BLACK : WHITE); + + Bitboard b, squaresToQueen, defendedSquares, unsafeSquares; + Score score = SCORE_ZERO; - for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++) + b = ei.pi->passed_pawns(Us); + + while (b) { - s = pos.piece_list(us, Piece, i); - - if (Piece == KNIGHT || Piece == QUEEN) - b = pos.piece_attacks(s); - else if (Piece == BISHOP) - b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.queens(us)); - else if (Piece == ROOK) - b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us)); - else - assert(false); + Square s = pop_lsb(&b); + + assert(pos.pawn_passed(Us, s)); - // Attacks and mobility - mob = evaluate_mobility(pos, b, us, them, ei); + int r = relative_rank(Us, s) - RANK_2; + int rr = r * (r - 1); - // Bishop and knight outposts squares - if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, them)) - evaluate_outposts(pos, us, them, ei, s); + // Base bonus based on rank + Value mbonus = Value(17 * rr), ebonus = Value(7 * (rr + r + 1)); - // Special patterns: trapped bishops on a7/h7/a2/h2 - // and trapped bishops on a1/h1/a8/h8 in Chess960. - if (Piece == BISHOP) + if (rr) { - if (bit_is_set(MaskA7H7[us], s)) - evaluate_trapped_bishop_a7h7(pos, s, us, ei); + Square blockSq = s + pawn_push(Us); - if (Chess960 && bit_is_set(MaskA1H1[us], s)) - evaluate_trapped_bishop_a1h1(pos, s, us, ei); - } + // Adjust bonus based on the king's proximity + ebonus += square_distance(pos.king_square(Them), blockSq) * 5 * rr + - square_distance(pos.king_square(Us ), blockSq) * 2 * rr; - if (Piece == ROOK || Piece == QUEEN) - { - // Queen or rook on 7th rank - 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); - } - } + // If blockSq is not the queening square then consider also a second push + if (relative_rank(Us, blockSq) != RANK_8) + ebonus -= square_distance(pos.king_square(Us), blockSq + pawn_push(Us)) * rr; - // 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 the pawn is free to advance, then increase the bonus + if (pos.empty(blockSq)) { - if (ei.pi->file_is_half_open(them, f)) - { - ei.mgValue += Sign[us] * RookOpenFileBonus; - ei.egValue += Sign[us] * RookOpenFileBonus; - } + squaresToQueen = forward_bb(Us, s); + + // If there is an enemy rook or queen attacking the pawn from behind, + // add all X-ray attacks by the rook or queen. Otherwise consider only + // the squares in the pawn's path attacked or occupied by the enemy. + if ( unlikely(forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN)) + && (forward_bb(Them, s) & pos.pieces(Them, ROOK, QUEEN) & pos.attacks_from(s))) + unsafeSquares = squaresToQueen; else - { - ei.mgValue += Sign[us] * RookHalfOpenFileBonus; - ei.egValue += Sign[us] * RookHalfOpenFileBonus; - } - } + unsafeSquares = squaresToQueen & (ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them)); - // 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; + if ( unlikely(forward_bb(Them, s) & pos.pieces(Us, ROOK, QUEEN)) + && (forward_bb(Them, s) & pos.pieces(Us, ROOK, QUEEN) & pos.attacks_from(s))) + defendedSquares = squaresToQueen; + else + defendedSquares = squaresToQueen & ei.attackedBy[Us][ALL_PIECES]; - ksq = pos.king_square(us); + // If there aren't any enemy attacks, assign a big bonus. Otherwise + // assign a smaller bonus if the block square isn't attacked. + int k = !unsafeSquares ? 15 : !(unsafeSquares & blockSq) ? 9 : 0; - 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.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2) - : Sign[us] * (TrappedRookPenalty - mob * 16); - } - 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.mgValue -= pos.can_castle(us)? Sign[us] * ((TrappedRookPenalty - mob * 16) / 2) - : Sign[us] * (TrappedRookPenalty - mob * 16); + // If the path to queen is fully defended, assign a big bonus. + // Otherwise assign a smaller bonus if the block square is defended. + if (defendedSquares == squaresToQueen) + k += 6; + + else if (defendedSquares & blockSq) + k += 4; + + mbonus += k * rr, ebonus += k * rr; } - } + } // rr != 0 + + if (pos.count(Us) < pos.count(Them)) + ebonus += ebonus / 4; + + score += make_score(mbonus, ebonus); } - } + if (Trace) + Tracing::terms[Us][Tracing::PASSED] = apply_weight(score, Weights[PassedPawns]); - // evaluate_king<>() assigns bonuses and penalties to a king of a given color. + // Add the scores to the middlegame and endgame eval + return apply_weight(score, Weights[PassedPawns]); + } - template - void evaluate_king(const Position& p, Color us, EvalInfo& ei) { - int shelter = 0, sign = Sign[us]; - Square s = p.king_square(us); + // evaluate_unstoppable_pawns() scores the most advanced among the passed and + // candidate pawns. In case opponent has no pieces but pawns, this is somewhat + // related to the possibility that pawns are unstoppable. - // King shelter - if (relative_rank(us, s) <= RANK_4) - { - shelter = ei.pi->get_king_shelter(p, us, s); - ei.mgValue += sign * Value(shelter); - } + Score evaluate_unstoppable_pawns(const Position& pos, Color us, const EvalInfo& ei) { - // King safety. This is quite complicated, and is almost certainly far - // from optimally tuned. - Color them = opposite_color(us); + Bitboard b = ei.pi->passed_pawns(us) | ei.pi->candidate_pawns(us); - if ( p.piece_count(them, QUEEN) >= 1 - && ei.kingAttackersCount[them] >= 2 - && p.non_pawn_material(them) >= QueenValueMidgame + RookValueMidgame - && ei.kingAdjacentZoneAttacksCount[them]) - { - // Is it the attackers turn to move? - bool sente = (them == p.side_to_move()); - - // Find the attacked squares around the king which has no defenders - // apart from the king itself - Bitboard undefended = - ei.attacked_by(them) & ~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) - & ei.attacked_by(us, KING); - - Bitboard occ = p.occupied_squares(), b, b2; - - // 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. - int attackUnits = - Min((ei.kingAttackersCount[them] * ei.kingAttackersWeight[them]) / 2, 25) - + (ei.kingAdjacentZoneAttacksCount[them] + count_1s_max_15(undefended)) * 3 - + InitKingDanger[relative_square(us, s)] - (shelter >> 5); - - // Analyse safe queen contact checks - b = undefended & ei.attacked_by(them, QUEEN) & ~p.pieces_of_color(them); - if (b) - { - Bitboard attackedByOthers = - ei.attacked_by(them, PAWN) | ei.attacked_by(them, KNIGHT) - | ei.attacked_by(them, BISHOP) | ei.attacked_by(them, ROOK); - - b &= attackedByOthers; - if (b) - { - // The bitboard b now contains the squares available for safe queen - // contact checks. - int count = count_1s_max_15(b); - attackUnits += QueenContactCheckBonus * count * (sente ? 2 : 1); - - // Is there a mate threat? - if (QueenContactMates && !p.is_check()) - { - Bitboard escapeSquares = - p.piece_attacks(s) & ~p.pieces_of_color(us) & ~attackedByOthers; - - while (b) - { - Square from, to = pop_1st_bit(&b); - 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 < p.piece_count(them, QUEEN); i++) - { - from = p.piece_list(them, QUEEN, i); - if ( bit_is_set(p.piece_attacks(from), to) - && !bit_is_set(p.pinned_pieces(them), from) - && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.rooks_and_queens(us)) - && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & p.bishops_and_queens(us))) - - ei.mateThreat[them] = make_move(from, to); - } - } - } - } - } - } - - // Analyse safe distance checks - if (QueenCheckBonus > 0 || RookCheckBonus > 0) - { - b = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - - // 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 = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - - // 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 = p.piece_attacks(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us); - - // 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 = p.discovered_check_candidates(them) & ~p.pawns(); - 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: - if (attackUnits < 0) - attackUnits = 0; - - if (attackUnits >= 100) - attackUnits = 99; - - // 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. - Value v = apply_weight(SafetyTable[attackUnits], WeightKingSafety[us]); - - ei.mgValue -= sign * v; - - if (us == p.side_to_move()) - ei.futilityMargin += v; - } + if (!b || pos.non_pawn_material(~us)) + return SCORE_ZERO; + + return Unstoppable * int(relative_rank(us, frontmost_sq(us, b))); } - // evaluate_passed_pawns() evaluates the passed pawns for both sides. + // 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. The aim is to improve play on game opening. + template + int evaluate_space(const Position& pos, const EvalInfo& ei) { - void evaluate_passed_pawns(const Position &pos, EvalInfo &ei) { + const Color Them = (Us == WHITE ? BLACK : WHITE); - bool hasUnstoppable[2] = {false, false}; - int movesToGo[2] = {100, 100}; + // 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[Us] + & ~pos.pieces(Us, PAWN) + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); - for (Color us = WHITE; us <= BLACK; us++) - { - Color them = opposite_color(us); - Square ourKingSq = pos.king_square(us); - Square theirKingSq = pos.king_square(them); - Bitboard b = ei.pi->passed_pawns() & pos.pawns(us), b2, b3, b4; + // 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); - while (b) - { - Square s = pop_1st_bit(&b); + // Since SpaceMask[Us] is fully on our half of the board + assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0); - assert(pos.piece_on(s) == piece_of_color_and_type(us, PAWN)); - assert(pos.pawn_is_passed(us, s)); + // Count safe + (behind & safe) with a single popcount + return popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); + } - 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); + // do_evaluate() is the evaluation entry point, called directly from evaluate() - // Adjust bonus based on king proximity - if (tr != 0) - { - 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)) - { - 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.rooks_and_queens(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_of_color(them) & pos.pieces_of_type(PAWN)) == 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); - } - } + template + Value do_evaluate(const Position& pos) { - // If the pawn is supported by a friendly pawn, increase bonus - b2 = pos.pawns(us) & neighboring_files_bb(s); - if (b2 & rank_bb(s)) - ebonus += Value(r * 20); - else if (pos.pawn_attacks(them, s) & b2) - ebonus += Value(r * 12); + assert(!pos.checkers()); - // 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) - { - 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); - } - } - } - // 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.rooks_and_queens(them)) - ebonus -= ebonus / 4; - } + EvalInfo ei; + Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; + Thread* thisThread = pos.this_thread(); - // 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); - } - } + // Initialize score by reading the incrementally updated scores included + // in the position object (material + piece square tables) and adding a + // Tempo bonus. Score is computed from the point of view of white. + score = pos.psq_score() + (pos.side_to_move() == WHITE ? Tempo : -Tempo); - // 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]) - { - // 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. - } - } + // Probe the material hash table + ei.mi = Material::probe(pos, thisThread->materialTable, thisThread->endgames); + score += 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); - // 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. + // Probe the pawn hash table + ei.pi = Pawns::probe(pos, thisThread->pawnsTable); + score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); - void evaluate_trapped_bishop_a7h7(const Position &pos, Square s, Color us, - EvalInfo &ei) { - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + // Initialize attack and king safety bitboards + init_eval_info(pos, ei); + init_eval_info(pos, ei); - 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); + ei.attackedBy[WHITE][ALL_PIECES] |= ei.attackedBy[WHITE][KING]; + ei.attackedBy[BLACK][ALL_PIECES] |= ei.attackedBy[BLACK][KING]; - 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.mgValue -= Sign[us] * TrappedBishopA7H7Penalty; - ei.egValue -= Sign[us] * TrappedBishopA7H7Penalty; - } - } + // Do not include in mobility squares protected by enemy pawns or occupied by our pawns or king + Bitboard mobilityArea[] = { ~(ei.attackedBy[BLACK][PAWN] | pos.pieces(WHITE, PAWN, KING)), + ~(ei.attackedBy[WHITE][PAWN] | pos.pieces(BLACK, PAWN, KING)) }; + + // Evaluate pieces and mobility + score += evaluate_pieces(pos, ei, mobility, mobilityArea); + score += apply_weight(mobility[WHITE] - mobility[BLACK], Weights[Mobility]); + // Evaluate kings after all other pieces because we need complete attack + // information when computing the king safety evaluation. + score += evaluate_king(pos, ei) + - evaluate_king(pos, ei); - // 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 tactical threats, we need full attack information including king + score += evaluate_threats(pos, ei) + - evaluate_threats(pos, ei); - void evaluate_trapped_bishop_a1h1(const Position &pos, Square s, Color us, - EvalInfo &ei) { - Piece pawn = piece_of_color_and_type(us, PAWN); - Square b2, b3, c3; + // Evaluate passed pawns, we need full attack information including king + score += evaluate_passed_pawns(pos, ei) + - evaluate_passed_pawns(pos, ei); - assert(Chess960); - assert(square_is_ok(s)); - assert(pos.piece_on(s) == piece_of_color_and_type(us, BISHOP)); + // If one side has only a king, score for potential unstoppable pawns + if (!pos.non_pawn_material(WHITE) || !pos.non_pawn_material(BLACK)) + score += evaluate_unstoppable_pawns(pos, WHITE, ei) + - evaluate_unstoppable_pawns(pos, BLACK, ei); - if (square_file(s) == FILE_A) + // Evaluate space for both sides, only in middlegame + if (ei.mi->space_weight()) { - b2 = relative_square(us, SQ_B2); - b3 = relative_square(us, SQ_B3); - c3 = relative_square(us, SQ_C3); + int s = evaluate_space(pos, ei) - evaluate_space(pos, ei); + score += apply_weight(s * ei.mi->space_weight(), Weights[Space]); } - else + + // Scale winning side if position is more drawish than it appears + ScaleFactor sf = eg_value(score) > VALUE_DRAW ? ei.mi->scale_factor(pos, WHITE) + : ei.mi->scale_factor(pos, BLACK); + + // If we don't already have an unusual scale factor, check for opposite + // colored bishop endgames, and use a lower scale for those. + if ( ei.mi->game_phase() < PHASE_MIDGAME + && pos.opposite_bishops() + && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) { - b2 = relative_square(us, SQ_G2); - b3 = relative_square(us, SQ_G3); - c3 = relative_square(us, SQ_F3); + // Ignoring any pawns, do both sides only have a single bishop and no + // other pieces? + if ( pos.non_pawn_material(WHITE) == BishopValueMg + && pos.non_pawn_material(BLACK) == BishopValueMg) + { + // 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.count(WHITE) + pos.count(BLACK) == 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 * sf / SCALE_FACTOR_NORMAL); } - if (pos.piece_on(b2) == pawn) - { - Value penalty; + // Interpolate between a middlegame and a (scaled by 'sf') endgame score + Value v = mg_value(score) * int(ei.mi->game_phase()) + + eg_value(score) * int(PHASE_MIDGAME - ei.mi->game_phase()) * sf / SCALE_FACTOR_NORMAL; - if (!pos.square_is_empty(b3)) - penalty = 2*TrappedBishopA1H1Penalty; - else if (pos.piece_on(c3) == pawn) - penalty = TrappedBishopA1H1Penalty; - else - penalty = TrappedBishopA1H1Penalty / 2; + v /= PHASE_MIDGAME; - ei.mgValue -= Sign[us] * penalty; - ei.egValue -= Sign[us] * penalty; + // In case of tracing add all single evaluation contributions for both white and black + if (Trace) + { + Tracing::add_term(Tracing::PST, pos.psq_score()); + Tracing::add_term(Tracing::IMBALANCE, ei.mi->material_value()); + Tracing::add_term(PAWN, ei.pi->pawns_value()); + Tracing::add_term(Tracing::MOBILITY, apply_weight(mobility[WHITE], Weights[Mobility]) + , apply_weight(mobility[BLACK], Weights[Mobility])); + Score w = ei.mi->space_weight() * evaluate_space(pos, ei); + Score b = ei.mi->space_weight() * evaluate_space(pos, ei); + Tracing::add_term(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); + Tracing::add_term(Tracing::TOTAL, score); + Tracing::ei = ei; + Tracing::sf = sf; } + + return pos.side_to_move() == WHITE ? v : -v; } - // 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, Color us, EvalInfo &ei) { + // Tracing function definitions - Color them = opposite_color(us); + double Tracing::to_cp(Value v) { return double(v) / PawnValueEg; } - // Find the safe squares for our pieces inside the area defined by - // SpaceMask[us]. A square is unsafe it is attacked by an enemy - // pawn, or if it is undefended and attacked by an enemy piece. + void Tracing::add_term(int idx, Score wScore, Score bScore) { - Bitboard safeSquares = SpaceMask[us] - & ~pos.pawns(us) - & ~ei.attacked_by(them, PAWN) - & ~(~ei.attacked_by(us) & ei.attacked_by(them)); + terms[WHITE][idx] = wScore; + terms[BLACK][idx] = bScore; + } - // Find all squares which are at most three squares behind some friendly - // pawn. - Bitboard behindFriendlyPawns = pos.pawns(us); - if (us == WHITE) - { - behindFriendlyPawns |= (behindFriendlyPawns >> 8); - behindFriendlyPawns |= (behindFriendlyPawns >> 16); - } - else - { - behindFriendlyPawns |= (behindFriendlyPawns << 8); - behindFriendlyPawns |= (behindFriendlyPawns << 16); + void Tracing::format_row(std::stringstream& ss, const char* name, int idx) { + + Score wScore = terms[WHITE][idx]; + Score bScore = terms[BLACK][idx]; + + switch (idx) { + case PST: case IMBALANCE: case PAWN: case TOTAL: + ss << std::setw(20) << name << " | --- --- | --- --- | " + << std::setw(5) << to_cp(mg_value(wScore - bScore)) << " " + << std::setw(5) << to_cp(eg_value(wScore - bScore)) << " \n"; + break; + default: + ss << std::setw(20) << name << " | " << std::noshowpos + << std::setw(5) << to_cp(mg_value(wScore)) << " " + << std::setw(5) << to_cp(eg_value(wScore)) << " | " + << std::setw(5) << to_cp(mg_value(bScore)) << " " + << std::setw(5) << to_cp(eg_value(bScore)) << " | " + << std::setw(5) << to_cp(mg_value(wScore - bScore)) << " " + << std::setw(5) << to_cp(eg_value(wScore - bScore)) << " \n"; } - - 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); } + std::string Tracing::do_trace(const Position& pos) { - // apply_weight() applies an evaluation weight to a value - - inline Value apply_weight(Value v, int w) { - return (v*w) / 0x100; - } + std::memset(terms, 0, sizeof(terms)); + Value v = do_evaluate(pos); + v = pos.side_to_move() == WHITE ? v : -v; // White's point of view - // 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. + 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"; - Value scale_by_game_phase(Value mv, Value ev, Phase ph, const ScaleFactor sf[]) { + format_row(ss, "Material, PST, Tempo", PST); + format_row(ss, "Material imbalance", IMBALANCE); + format_row(ss, "Pawns", PAWN); + format_row(ss, "Knights", KNIGHT); + format_row(ss, "Bishops", BISHOP); + format_row(ss, "Rooks", ROOK); + format_row(ss, "Queens", QUEEN); + format_row(ss, "Mobility", MOBILITY); + format_row(ss, "King safety", KING); + format_row(ss, "Threats", THREAT); + format_row(ss, "Passed pawns", PASSED); + format_row(ss, "Space", SPACE); - assert(mv > -VALUE_INFINITE && mv < VALUE_INFINITE); - assert(ev > -VALUE_INFINITE && ev < VALUE_INFINITE); - assert(ph >= PHASE_ENDGAME && ph <= PHASE_MIDGAME); + ss << "---------------------+-------------+-------------+-------------\n"; + format_row(ss, "Total", TOTAL); - ev = apply_scale_factor(ev, sf[(ev > Value(0) ? WHITE : BLACK)]); + ss << "\nTotal Evaluation: " << to_cp(v) << " (white side)\n"; - Value result = Value(int((mv * ph + ev * (128 - ph)) / 128)); - return Value(int(result) & ~(GrainSize - 1)); + return ss.str(); } +} // namespace + - // compute_weight() computes the value of an evaluation weight, by combining - // an UCI-configurable weight with an internal weight. +namespace Eval { - int compute_weight(int uciWeight, int internalWeight) { + /// evaluate() is the main evaluation function. It returns a static evaluation + /// of the position always from the point of view of the side to move. - uciWeight = (uciWeight * 0x100) / 100; - return (uciWeight * internalWeight) / 0x100; + Value evaluate(const Position& pos) { + return do_evaluate(pos); } - // helper used in read_weights() - int weight_option(const std::string& opt, int weight) { - - return compute_weight(get_option_value_int(opt), weight); + /// 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. It's mainly used for + /// debugging. + std::string trace(const Position& pos) { + return Tracing::do_trace(pos); } - // init_safety() initizes the king safety evaluation, based on UCI - // parameters. It is called from read_weights(). - - void init_safety() { + /// init() computes evaluation weights from the corresponding UCI parameters + /// and setup king tables. - 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"); + void init() { - 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"); + Weights[Mobility] = weight_option("Mobility (Midgame)", "Mobility (Endgame)", WeightsInternal[Mobility]); + Weights[PawnStructure] = weight_option("Pawn Structure (Midgame)", "Pawn Structure (Endgame)", WeightsInternal[PawnStructure]); + Weights[PassedPawns] = weight_option("Passed Pawns (Midgame)", "Passed Pawns (Endgame)", WeightsInternal[PassedPawns]); + Weights[Space] = weight_option("Space", "Space", WeightsInternal[Space]); + Weights[KingDangerUs] = weight_option("Cowardice", "Cowardice", WeightsInternal[KingDangerUs]); + Weights[KingDangerThem] = weight_option("Aggressiveness", "Aggressiveness", WeightsInternal[KingDangerThem]); - 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))); - } + const double MaxSlope = 30; + const double Peak = 1280; - for (int i = 0; i < 100; i++) + for (int t = 0, i = 1; 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); + t = int(std::min(Peak, std::min(0.4 * i * i, t + MaxSlope))); - if (SafetyTable[i] > Value(peak)) - SafetyTable[i] = Value(peak); + KingDanger[1][i] = apply_weight(make_score(t, 0), Weights[KingDangerUs]); + KingDanger[0][i] = apply_weight(make_score(t, 0), Weights[KingDangerThem]); } } -} + +} // namespace Eval