X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fevaluate.cpp;h=bbca9964f4337d9506c23d0d49353af9f0e2e9d3;hp=f70014e293d2ac9d88d5e3fe9d62f8102ea70e2c;hb=7ea5659c5fe0325f1b6ee5fec06ecd0f066e81c3;hpb=460892382a11cca0fe645390ff96910bf03f6b20 diff --git a/src/evaluate.cpp b/src/evaluate.cpp index f70014e2..bbca9964 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) 2008-2014 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 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 @@ -19,6 +19,7 @@ #include #include +#include // For std::memset #include #include @@ -26,22 +27,53 @@ #include "evaluate.h" #include "material.h" #include "pawns.h" -#include "thread.h" -#include "uci.h" namespace { + namespace Trace { + + enum Term { // First 8 entries are for PieceType + MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERM_NB + }; + + double scores[TERM_NB][COLOR_NB][PHASE_NB]; + + double to_cp(Value v) { return double(v) / PawnValueEg; } + + 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)); + } + + void add(int idx, Score w, Score b = SCORE_ZERO) { + add(idx, WHITE, w); add(idx, BLACK, b); + } + + std::ostream& operator<<(std::ostream& os, Term t) { + + 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] << " | "; + + os << std::setw(5) << scores[t][WHITE][MG] - scores[t][BLACK][MG] << " " + << std::setw(5) << scores[t][WHITE][EG] - scores[t][BLACK][EG] << " \n"; + + return os; + } + } + + using namespace Trace; + // 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. + // 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 @@ -58,45 +90,35 @@ namespace { // 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 + // 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 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]. + // 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]; + Pawns::Entry* pi; }; - namespace Tracing { - enum Terms { // First 8 entries are for PieceType - MATERIAL = 8, IMBALANCE, MOBILITY, THREAT, PASSED, SPACE, TOTAL, TERMS_NB - }; + // Evaluation weights, indexed by the corresponding evaluation term + enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety }; - Score scores[COLOR_NB][TERMS_NB]; - EvalInfo ei; - ScaleFactor sf; + const struct Weight { int mg, eg; } Weights[] = { + {289, 344}, {233, 201}, {221, 273}, {46, 0}, {322, 0} + }; - double to_cp(Value v); - void write(int idx, Color c, Score s); - void write(int idx, Score w, Score b = SCORE_ZERO); - void print(std::stringstream& ss, const char* name, int idx); - std::string do_trace(const Position& pos); + Score operator*(Score s, const Weight& w) { + return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); } - // Evaluation weights, indexed by evaluation term - enum { Mobility, PawnStructure, PassedPawns, Space, KingSafety }; - const struct Weight { int mg, eg; } Weights[] = { - {289, 344}, {233, 201}, {221, 273}, {46, 0}, {318, 0} - }; - typedef Value V; + #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) // MobilityBonus[PieceType][attacked] contains bonuses for middle and end @@ -104,64 +126,71 @@ namespace { // 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) } + { S(-68,-49), S(-46,-33), S(-3,-12), S( 5, -4), S( 9, 11), S(15, 16), // Knights + S( 23, 27), S( 33, 28), S(37, 29) }, + { S(-49,-44), S(-23,-16), S(16, 1), S(29, 16), S(40, 25), S(51, 34), // Bishops + S( 55, 43), S( 61, 49), S(64, 51), S(68, 52), S(73, 55), S(75, 60), + S( 80, 65), S( 86, 66) }, + { S(-50,-57), S(-28,-22), S(-11, 7), S(-1, 29), S( 0, 39), S( 1, 46), // Rooks + S( 10, 66), S( 16, 79), S(22, 86), S(23,103), S(30,109), S(33,111), + S( 37,115), S( 38,119), S(48,124) }, + { S(-43,-30), S(-27,-15), S( 1, -5), S( 2, -3), S(14, 10), S(18, 24), // Queens + S( 20, 27), S( 33, 37), S(33, 38), S(34, 43), S(40, 46), S(43, 56), + S( 46, 61), S( 52, 63), S(52, 63), S(57, 65), S(60, 70), S(61, 74), + S( 67, 80), S( 76, 82), S(77, 88), S(82, 94), S(86, 95), S(90, 96), + S( 94, 99), S( 96,100), S(99,111), S(99,112) } }; - // 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[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(42,11), S(63,17) }, // Knights + { S(18, 5), S(27, 8) } // Bishops }; - // Threat[attacking][attacked] contains bonuses according to which piece - // type attacks which one. - const Score Threat[][PIECE_TYPE_NB] = { - { S(0, 0), S(0, 38), S(32, 45), S(32, 45), S(41,100), S(35,104) }, // Minor - { S(0, 0), S(7, 28), S(20, 49), S(20, 49), S(8 , 42), S(23, 44) } // Major + // Threat[defended/weak][minor/rook attacking][attacked PieceType] contains + // bonuses according to which piece type attacks which one. + const Score Threat[][2][PIECE_TYPE_NB] = { + { { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) }, // Minor on Defended + { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Rook on Defended + { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) }, // Minor on Weak + { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } } // Rook on Weak }; // 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(80, 119), S(80, 119), S(117, 199), S(127, 218) + const Score ThreatenedByPawn[PIECE_TYPE_NB] = { + S(0, 0), S(0, 0), S(107, 138), S(84, 122), S(114, 203), S(121, 217) }; + // Passed[mg/eg][rank] contains midgame and endgame bonuses for passed pawns. + // We don't use a Score because we process the two components independently. + const Value Passed[][RANK_NB] = { + { V(0), V( 1), V(34), V(90), V(214), V(328) }, + { V(7), V(14), V(37), V(63), V(134), V(189) } + }; + + // PassedFile[File] contains a bonus according to the file of a passed pawn. + const Score PassedFile[] = { + S( 14, 13), S( 2, 5), S(-3, -4), S(-19, -14), + S(-19, -14), S(-3, -4), S( 2, 5), S( 14, 13) + }; + + const Score ThreatenedByHangingPawn = S(40, 60); + // Assorted bonuses and penalties used by evaluation - const Score KingOnOne = S(2 , 58); - const Score KingOnMany = S(6 ,125); - const Score RookOnPawn = S(10, 28); - const Score RookOpenFile = S(43, 21); - const Score RookSemiOpenFile = S(19, 10); - const Score BishopPawns = S( 8, 12); - const Score MinorBehindPawn = S(16, 0); - const Score TrappedRook = S(92, 0); - const Score Unstoppable = S( 0, 20); - const Score Hanging = S(23, 20); + const Score KingOnOne = S( 2, 58); + const Score KingOnMany = S( 6,125); + const Score RookOnPawn = S( 7, 27); + const Score RookOnOpenFile = S(43, 21); + const Score RookOnSemiOpenFile = S(19, 10); + const Score BishopPawns = S( 8, 12); + const Score MinorBehindPawn = S(16, 0); + const Score TrappedRook = S(92, 0); + const Score Unstoppable = S( 0, 20); + const Score Hanging = S(31, 26); + const Score PawnAttackThreat = S(20, 20); + const Score Checked = S(20, 20); // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only @@ -169,42 +198,32 @@ namespace { const Score TrappedBishopA1H1 = S(50, 50); #undef S + #undef V // SpaceMask[Color] contains the area of the board which is considered // by the space evaluation. In the middlegame, each side is given a bonus // based on how many squares inside this area are safe and available for // friendly minor pieces. - const Bitboard SpaceMask[] = { + const Bitboard SpaceMask[COLOR_NB] = { (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank2BB | Rank3BB | Rank4BB), (FileCBB | FileDBB | FileEBB | FileFBB) & (Rank7BB | Rank6BB | Rank5BB) }; - // King danger constants and variables. The king danger scores are taken - // from KingDanger[]. Various little "meta-bonuses" measuring the strength + // King danger constants and variables. The king danger scores are looked-up + // in KingDanger[]. Various little "meta-bonuses" measuring the strength // of the enemy attack are added up into an integer, which is used as an // index to KingDanger[]. - // - // KingAttackWeights[PieceType] contains king attack weights by piece type - const int KingAttackWeights[] = { 0, 0, 2, 2, 3, 5 }; - - // Bonuses for enemy's safe checks - const int QueenContactCheck = 24; - const int RookContactCheck = 16; - const int QueenCheck = 12; - const int RookCheck = 8; - const int BishopCheck = 2; - const int KnightCheck = 3; + Score KingDanger[512]; - // KingDanger[attackUnits] contains the actual king danger weighted - // scores, indexed by a calculated integer number. - Score KingDanger[128]; - - const int ScalePawnSpan[2] = { 38, 56 }; + // KingAttackWeights[PieceType] contains king attack weights by piece type + const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 7, 5, 4, 1 }; - // 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); - } + // Penalties for enemy's safe checks + const int QueenContactCheck = 89; + const int QueenCheck = 50; + const int RookCheck = 45; + const int BishopCheck = 6; + const int KnightCheck = 14; // init_eval_info() initializes king bitboards for given color adding @@ -213,16 +232,16 @@ namespace { template void init_eval_info(const Position& pos, EvalInfo& ei) { - const Color Them = (Us == WHITE ? BLACK : WHITE); + const Color Them = (Us == WHITE ? BLACK : WHITE); const Square Down = (Us == WHITE ? DELTA_S : DELTA_N); ei.pinnedPieces[Us] = pos.pinned_pieces(Us); - - 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); + 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); // Init king safety tables only if we are going to use them - if (pos.non_pawn_material(Us) > QueenValueMg + PawnValueMg) + if (pos.non_pawn_material(Us) >= QueenValueMg) { ei.kingRing[Them] = b | shift_bb(b); b &= ei.attackedBy[Us][PAWN]; @@ -234,37 +253,10 @@ namespace { } - // evaluate_outpost() evaluates bishop and knight outpost squares - - template - Score evaluate_outpost(const Position& pos, const EvalInfo& ei, Square s) { - - const Color Them = (Us == WHITE ? BLACK : WHITE); - - assert (Pt == BISHOP || Pt == KNIGHT); - - // Initial bonus based on square - Value bonus = Outpost[Pt == BISHOP][relative_square(Us, s)]; - - // 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)) - { - 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 * 2, bonus / 2); - } - - // 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) { + template + Score evaluate_pieces(const Position& pos, EvalInfo& ei, Score* mobility, const Bitboard* mobilityArea) { Bitboard b; Square s; @@ -272,7 +264,7 @@ namespace { const PieceType NextPt = (Us == WHITE ? Pt : PieceType(Pt + 1)); const Color Them = (Us == WHITE ? BLACK : WHITE); - const Square* pl = pos.list(Us); + const Square* pl = pos.squares(Us); ei.attackedBy[Us][Pt] = 0; @@ -284,7 +276,7 @@ namespace { : pos.attacks_from(s); if (ei.pinnedPieces[Us] & s) - b &= LineBB[pos.king_square(Us)][s]; + b &= LineBB[pos.square(Us)][s]; ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b; @@ -302,96 +294,92 @@ namespace { | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]); - int mob = Pt != QUEEN ? popcount(b & mobilityArea[Us]) - : popcount(b & mobilityArea[Us]); + int mob = popcount(b & mobilityArea[Us]); 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]; - 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 outpost square - if (!(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) - score += evaluate_outpost(pos, ei, s); + // Bonus for outpost square + if ( relative_rank(Us, s) >= RANK_4 + && relative_rank(Us, s) <= RANK_6 + && !(pos.pieces(Them, PAWN) & pawn_attack_span(Us, s))) + score += Outpost[Pt == BISHOP][!!(ei.attackedBy[Us][PAWN] & s)]; - // Bishop or knight behind a pawn + // 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 same color square of 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) { - // Rook piece attacking enemy pawns on the same rank/file + // Bonus for aligning with 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; + Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]; + if (alignedPawns) + score += popcount(alignedPawns) * RookOnPawn; } - // Give a bonus for a rook on a open or semi-open file + // Bonus when on an 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; - - if (mob > 3 || ei.pi->semiopen_file(Us, file_of(s))) - continue; + score += ei.pi->semiopen_file(Them, file_of(s)) ? RookOnOpenFile : RookOnSemiOpenFile; - 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 * 22, 0)) * (1 + !pos.can_castle(Us)); - } + // Penalize when trapped by the king, even more if king cannot castle + if (mob <= 3 && !ei.pi->semiopen_file(Us, file_of(s))) + { + Square ksq = pos.square(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 ( ((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)); + } } } - if (Trace) - Tracing::write(Pt, Us, score); + if (DoTrace) + Trace::add(Pt, Us, score); - return score - evaluate_pieces(pos, ei, mobility, mobilityArea); + // Recursively call evaluate_pieces() of next piece type until KING excluded + return score - evaluate_pieces(pos, ei, mobility, mobilityArea); } template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*, Bitboard*) { return SCORE_ZERO; } + Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } template<> - Score evaluate_pieces(const Position&, EvalInfo&, Score*, Bitboard*) { return SCORE_ZERO; } + Score evaluate_pieces(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; } // evaluate_king() assigns bonuses and penalties to a king of a given color - template + template Score evaluate_king(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); Bitboard undefended, b, b1, b2, safe; int attackUnits; - const Square ksq = pos.king_square(Us); + const Square ksq = pos.square(Us); // King shelter and enemy pawns storm Score score = ei.pi->king_safety(pos, ksq); @@ -408,153 +396,173 @@ namespace { | 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 + // 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(20, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2) - + 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount(undefended)) - + 2 * (ei.pinnedPieces[Us] != 0) - - mg_value(score) / 32 - - !pos.count(Them) * 15; + 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 that are attacked by the enemy's - // queen... + // undefended squares around the king reachable by the enemy 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); - } - - // 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); - - // Consider only squares where the enemy's rook gives check - b &= PseudoAttacks[ROOK][ksq]; - - if (b) - { - // ...and then remove squares not supported by another enemy piece - b &= ( ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] - | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][QUEEN]); + b &= ei.attackedBy[Them][PAWN] | ei.attackedBy[Them][KNIGHT] + | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]; if (b) - attackUnits += RookContactCheck * popcount(b); + attackUnits += QueenContactCheck * popcount(b); } // Analyse the enemy's safe distance checks for sliders and knights - safe = ~(pos.pieces(Them) | ei.attackedBy[Us][ALL_PIECES]); + safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them)); - b1 = pos.attacks_from(ksq) & safe; + b1 = pos.attacks_from(ksq) & safe; b2 = pos.attacks_from(ksq) & safe; // Enemy queen safe checks b = (b1 | b2) & ei.attackedBy[Them][QUEEN]; if (b) + { attackUnits += QueenCheck * popcount(b); + score -= Checked; + } // Enemy rooks safe checks b = b1 & ei.attackedBy[Them][ROOK]; if (b) + { attackUnits += RookCheck * popcount(b); + score -= Checked; + } // Enemy bishops safe checks b = b2 & ei.attackedBy[Them][BISHOP]; if (b) + { attackUnits += BishopCheck * popcount(b); + score -= Checked; + } // Enemy knights safe checks b = pos.attacks_from(ksq) & ei.attackedBy[Them][KNIGHT] & safe; if (b) + { attackUnits += KnightCheck * popcount(b); - - // To index KingDanger[] attackUnits must be in [0, 99] range - attackUnits = std::min(99, std::max(0, attackUnits)); + score -= Checked; + } // Finally, extract the king danger score from the KingDanger[] // array and subtract the score from evaluation. - score -= KingDanger[attackUnits]; + score -= KingDanger[std::max(std::min(attackUnits, 399), 0)]; } - if (Trace) - Tracing::write(KING, Us, score); + if (DoTrace) + Trace::add(KING, Us, score); return score; } - // max_piece_type() is a helper function used by evaluate_threats() to get - // the value of the biggest PieceType of color C in 'target' bitboard. + // evaluate_threats() assigns bonuses according to the type of attacking piece + // and the type of attacked one. - template - inline PieceType max_piece_type(const Position& pos, const Bitboard target) { + template + Score evaluate_threats(const Position& pos, const EvalInfo& ei) { - assert(target & (pos.pieces(C) ^ pos.pieces(C, KING))); + 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); - for (PieceType pt = QUEEN; pt > PAWN; --pt) - if (target & pos.pieces(C, pt)) - return pt; + enum { Defended, Weak }; + enum { Minor, Rook }; - return PAWN; - } + Bitboard b, weak, defended, safeThreats; + Score score = SCORE_ZERO; + // Non-pawn enemies attacked by a pawn + weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN]; - // evaluate_threats() assigns bonuses according to the type of attacking piece - // and the type of attacked one. + if (weak) + { + b = pos.pieces(Us, PAWN) & ( ~ei.attackedBy[Them][ALL_PIECES] + | ei.attackedBy[Us][ALL_PIECES]); - template - Score evaluate_threats(const Position& pos, const EvalInfo& ei) { + safeThreats = (shift_bb(b) | shift_bb(b)) & weak; - const Color Them = (Us == WHITE ? BLACK : WHITE); + if (weak ^ safeThreats) + score += ThreatenedByHangingPawn; - enum { Minor, Major }; + while (safeThreats) + score += ThreatenedByPawn[type_of(pos.piece_on(pop_lsb(&safeThreats)))]; + } - Bitboard b, weakEnemies, protectedEnemies; - Score score = SCORE_ZERO; + // Non-pawn enemies defended by a pawn + defended = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Them][PAWN]; - // Enemies defended by a pawn and under our attack by a minor piece - protectedEnemies = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) - & ei.attackedBy[Them][PAWN] - & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + // Add a bonus according to the kind of attacking pieces + if (defended) + { + b = defended & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + while (b) + score += Threat[Defended][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - if (protectedEnemies) - score += Threat[Minor][max_piece_type(pos, protectedEnemies)]; + b = defended & ei.attackedBy[Us][ROOK]; + while (b) + score += Threat[Defended][Rook][type_of(pos.piece_on(pop_lsb(&b)))]; + } // Enemies not defended by a pawn and under our attack - weakEnemies = pos.pieces(Them) - & ~ei.attackedBy[Them][PAWN] - & ei.attackedBy[Us][ALL_PIECES]; + weak = 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) + // Add a bonus according to the kind of attacking pieces + if (weak) { - b = weakEnemies & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); - if (b) - score += Threat[Minor][max_piece_type(pos, b)]; + b = weak & (ei.attackedBy[Us][KNIGHT] | ei.attackedBy[Us][BISHOP]); + while (b) + score += Threat[Weak][Minor][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]); - if (b) - score += Threat[Major][max_piece_type(pos, b)]; + b = weak & ei.attackedBy[Us][ROOK]; + while (b) + score += Threat[Weak][Rook][type_of(pos.piece_on(pop_lsb(&b)))]; - b = weakEnemies & ~ei.attackedBy[Them][ALL_PIECES]; + b = weak & ~ei.attackedBy[Them][ALL_PIECES]; if (b) - score += more_than_one(b) ? Hanging * popcount(b) : Hanging; + score += Hanging * popcount(b); - b = weakEnemies & ei.attackedBy[Us][KING]; + b = weak & ei.attackedBy[Us][KING]; if (b) score += more_than_one(b) ? KingOnMany : KingOnOne; } - if (Trace) - Tracing::write(Tracing::THREAT, Us, score); + // 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())); + + b &= ~pos.pieces() + & ~ei.attackedBy[Them][PAWN] + & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]); + + b = (shift_bb(b) | shift_bb(b)) + & pos.pieces(Them) + & ~ei.attackedBy[Us][PAWN]; + + if (b) + score += popcount(b) * PawnAttackThreat; + + if (DoTrace) + Trace::add(THREAT, Us, score); return score; } @@ -562,7 +570,7 @@ namespace { // evaluate_passed_pawns() evaluates the passed pawns of the given color - template + template Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); @@ -581,20 +589,19 @@ namespace { int r = relative_rank(Us, s) - RANK_2; int rr = r * (r - 1); - // Base bonus based on rank - Value mbonus = Value(17 * rr), ebonus = Value(7 * (rr + r + 1)); + Value mbonus = Passed[MG][r], ebonus = Passed[EG][r]; if (rr) { Square blockSq = s + pawn_push(Us); // 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; + ebonus += distance(pos.square(Them), blockSq) * 5 * rr + - distance(pos.square(Us ), blockSq) * 2 * rr; // 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; + ebonus -= distance(pos.square(Us), blockSq + pawn_push(Us)) * rr; // If the pawn is free to advance, then increase the bonus if (pos.empty(blockSq)) @@ -614,7 +621,7 @@ namespace { // If there aren't any enemy attacks, assign a big bonus. Otherwise // assign a smaller bonus if the block square isn't attacked. - int k = !unsafeSquares ? 15 : !(unsafeSquares & blockSq) ? 9 : 0; + int k = !unsafeSquares ? 18 : !(unsafeSquares & blockSq) ? 8 : 0; // If the path to queen is fully defended, assign a big bonus. // Otherwise assign a smaller bonus if the block square is defended. @@ -633,26 +640,14 @@ namespace { if (pos.count(Us) < pos.count(Them)) ebonus += ebonus / 4; - score += make_score(mbonus, ebonus); + score += make_score(mbonus, ebonus) + PassedFile[file_of(s)]; } - if (Trace) - Tracing::write(Tracing::PASSED, Us, apply_weight(score, Weights[PassedPawns])); + if (DoTrace) + Trace::add(PASSED, Us, score * Weights[PassedPawns]); // Add the scores to the middlegame and endgame eval - return apply_weight(score, Weights[PassedPawns]); - } - - - // evaluate_unstoppable_pawns() scores the most advanced passed pawn. In case - // both players have no pieces but pawns, this is somewhat related to the - // possibility that pawns are unstoppable. - - Score evaluate_unstoppable_pawns(Color us, const EvalInfo& ei) { - - Bitboard b = ei.pi->passed_pawns(us); - - return b ? Unstoppable * int(relative_rank(us, frontmost_sq(us, b))) : SCORE_ZERO; + return score * Weights[PassedPawns]; } @@ -660,10 +655,10 @@ namespace { // 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. + // twice. Finally, the space bonus is multiplied by a weight. The aim is to + // improve play on game opening. template - int evaluate_space(const Position& pos, const EvalInfo& ei) { + Score evaluate_space(const Position& pos, const EvalInfo& ei) { const Color Them = (Us == WHITE ? BLACK : WHITE); @@ -680,242 +675,228 @@ namespace { behind |= (Us == WHITE ? behind >> 8 : behind << 8); behind |= (Us == WHITE ? behind >> 16 : behind << 16); - // Since SpaceMask[Us] is fully on our half of the board + // 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 - return popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe)); - } - - - // do_evaluate() is the evaluation entry point, called directly from evaluate() + // ...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); - template - Value do_evaluate(const Position& pos) { - - assert(!pos.checkers()); - - EvalInfo ei; - Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; - Thread* thisThread = pos.this_thread(); + return make_score(bonus * weight * weight, 0); + } - // Initialize score by reading the incrementally updated scores included - // in the position object (material + piece square tables). - // Score is computed from the point of view of white. - score = pos.psq_score(); - // Probe the material hash table - ei.mi = Material::probe(pos, thisThread->materialTable, thisThread->endgames); - score += ei.mi->material_value(); + // evaluate_initiative() computes the initiative correction value for the position, i.e. + // second order bonus/malus based on the known attacking/defending status of the players. + Score evaluate_initiative(const Position& pos, const EvalInfo& ei, const Score positional_score) { - // 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) + Eval::Tempo; + int pawns = pos.count(WHITE) + pos.count(BLACK); + int king_separation = distance(pos.square(WHITE), pos.square(BLACK)); + int asymmetry = ei.pi->pawn_asymmetry(); - // Probe the pawn hash table - ei.pi = Pawns::probe(pos, thisThread->pawnsTable); - score += apply_weight(ei.pi->pawns_value(), Weights[PawnStructure]); + // Compute the initiative bonus for the attacking side + int attacker_bonus = 8 * (pawns + asymmetry + king_separation) - 120; - // Initialize attack and king safety bitboards - init_eval_info(pos, ei); - init_eval_info(pos, ei); + // Now apply the bonus: note that we find the attacking side by extracting the sign + // of the endgame value of "positional_score", and that we carefully cap the bonus so + // that the endgame score with the correction will never be divided by more than two. + int eg = eg_value(positional_score); + int value = ((eg > 0) - (eg < 0)) * std::max( attacker_bonus , -abs( eg / 2 ) ); - ei.attackedBy[WHITE][ALL_PIECES] |= ei.attackedBy[WHITE][KING]; - ei.attackedBy[BLACK][ALL_PIECES] |= ei.attackedBy[BLACK][KING]; + return make_score( 0 , value ) ; + } - // 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)) }; +} // namespace - // 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() is the main evaluation function. It returns a static evaluation +/// of the position always from the point of view of the side to move. - // Evaluate tactical threats, we need full attack information including king - score += evaluate_threats(pos, ei) - - evaluate_threats(pos, ei); +template +Value Eval::evaluate(const Position& pos) { - // Evaluate passed pawns, we need full attack information including king - score += evaluate_passed_pawns(pos, ei) - - evaluate_passed_pawns(pos, ei); + assert(!pos.checkers()); - // If both sides have only pawns, score for potential unstoppable pawns - if (!pos.non_pawn_material(WHITE) && !pos.non_pawn_material(BLACK)) - score += evaluate_unstoppable_pawns(WHITE, ei) - - evaluate_unstoppable_pawns(BLACK, ei); + EvalInfo ei; + Score score, mobility[2] = { SCORE_ZERO, SCORE_ZERO }; - // Evaluate space for both sides, only in middlegame - if (ei.mi->space_weight()) - { - int s = evaluate_space(pos, ei) - evaluate_space(pos, ei); - score += apply_weight(s * ei.mi->space_weight(), Weights[Space]); - } + // Initialize score by reading the incrementally updated scores included + // in the position object (material + piece square tables). + // Score is computed from the point of view of white. + score = pos.psq_score(); - // Scale winning side if position is more drawish than it appears - Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK; - ScaleFactor sf = ei.mi->scale_factor(pos, strongSide); + // Probe the material hash table + Material::Entry* me = Material::probe(pos); + score += me->imbalance(); - // 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.mi->game_phase() < PHASE_MIDGAME - && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) - { - if (pos.opposite_bishops()) - { - // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) - // is almost a draw, in case of KBP vs KB is even more a draw. - if ( pos.non_pawn_material(WHITE) == BishopValueMg - && pos.non_pawn_material(BLACK) == BishopValueMg) - sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(32) : ScaleFactor(8); - - // Endgame with opposite-colored bishops, but also other pieces. Still - // a bit drawish, but not as drawish as with only the two bishops. - else - sf = ScaleFactor(50 * sf / SCALE_FACTOR_NORMAL); - } - // Endings where weaker side can place his king in front of the opponent's - // pawns are drawish. - else if ( abs(eg_value(score)) <= BishopValueEg - && ei.pi->pawn_span(strongSide) <= 1 - && !pos.pawn_passed(~strongSide, pos.king_square(~strongSide))) - sf = ScaleFactor(ScalePawnSpan[ei.pi->pawn_span(strongSide)]); - } + // If we have a specialized evaluation function for the current material + // configuration, call it and return. + if (me->specialized_eval_exists()) + return me->evaluate(pos); - // 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; + // Probe the pawn hash table + ei.pi = Pawns::probe(pos); + score += ei.pi->pawns_score() * Weights[PawnStructure]; - v /= int(PHASE_MIDGAME); + // Initialize attack and king safety bitboards + ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; + init_eval_info(pos, ei); + init_eval_info(pos, ei); - // In case of tracing add all single evaluation contributions for both white and black - if (Trace) - { - Tracing::write(Tracing::MATERIAL, pos.psq_score()); - Tracing::write(Tracing::IMBALANCE, ei.mi->material_value()); - Tracing::write(PAWN, ei.pi->pawns_value()); - Tracing::write(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::write(Tracing::SPACE, apply_weight(w, Weights[Space]), apply_weight(b, Weights[Space])); - Tracing::write(Tracing::TOTAL, score); - Tracing::ei = ei; - Tracing::sf = sf; - } + // 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) + }; - return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; - } + // Do not include in mobility squares protected by enemy pawns, or occupied + // by our blocked pawns or king. + Bitboard mobilityArea[] = { + ~(ei.attackedBy[BLACK][PAWN] | blockedPawns[WHITE] | pos.square(WHITE)), + ~(ei.attackedBy[WHITE][PAWN] | blockedPawns[BLACK] | pos.square(BLACK)) + }; + // Evaluate pieces and mobility + score += evaluate_pieces(pos, ei, mobility, mobilityArea); + score += (mobility[WHITE] - mobility[BLACK]) * Weights[Mobility]; - // Tracing function definitions + // 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); - double Tracing::to_cp(Value v) { return double(v) / PawnValueEg; } + // Evaluate tactical threats, we need full attack information including king + score += evaluate_threats(pos, ei) + - evaluate_threats(pos, ei); - void Tracing::write(int idx, Color c, Score s) { scores[c][idx] = s; } + // Evaluate passed pawns, we need full attack information including king + score += evaluate_passed_pawns(pos, ei) + - evaluate_passed_pawns(pos, ei); - void Tracing::write(int idx, Score w, Score b) { + // 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 += int(relative_rank(WHITE, frontmost_sq(WHITE, b))) * Unstoppable; - write(idx, WHITE, w); - write(idx, BLACK, b); + if ((b = ei.pi->passed_pawns(BLACK)) != 0) + score -= int(relative_rank(BLACK, frontmost_sq(BLACK, b))) * Unstoppable; } - void Tracing::print(std::stringstream& ss, const char* name, int idx) { - - Score wScore = scores[WHITE][idx]; - Score bScore = scores[BLACK][idx]; - - switch (idx) { - case MATERIAL: case IMBALANCE: case PAWN: case TOTAL: - ss << std::setw(15) << 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(15) << 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"; - } + // 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)) * Weights[Space]; + + // Evaluate initiative + score += evaluate_initiative(pos, ei, score); + + // Scale winning side if position is more drawish than it appears + Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK; + ScaleFactor sf = me->scale_factor(pos, strongSide); + + // If we don't already have an unusual scale factor, check for certain + // types of endgames, and use a lower scale for those. + if ( me->game_phase() < PHASE_MIDGAME + && (sf == SCALE_FACTOR_NORMAL || sf == SCALE_FACTOR_ONEPAWN)) + { + if (pos.opposite_bishops()) + { + // Endgame with opposite-colored bishops and no other pieces (ignoring pawns) + // is almost a draw, in case of KBP vs KB is even more a draw. + if ( pos.non_pawn_material(WHITE) == BishopValueMg + && pos.non_pawn_material(BLACK) == BishopValueMg) + sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(31) : ScaleFactor(9); + + // Endgame with opposite-colored bishops, but also other pieces. Still + // a bit drawish, but not as drawish as with only the two bishops. + else + sf = ScaleFactor(46 * sf / SCALE_FACTOR_NORMAL); + } + // Endings where weaker side can place his king in front of the opponent's + // pawns are drawish. + else if ( abs(eg_value(score)) <= BishopValueEg + && ei.pi->pawn_span(strongSide) <= 1 + && !pos.pawn_passed(~strongSide, pos.square(~strongSide))) + sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37); } - std::string Tracing::do_trace(const Position& pos) { - - std::memset(scores, 0, sizeof(scores)); + // Interpolate between a middlegame and a (scaled by 'sf') endgame score + Value v = mg_value(score) * int(me->game_phase()) + + eg_value(score) * int(PHASE_MIDGAME - me->game_phase()) * sf / SCALE_FACTOR_NORMAL; - Value v = do_evaluate(pos); - v = pos.side_to_move() == WHITE ? v : -v; // White's point of view + v /= int(PHASE_MIDGAME); - 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"; - - print(ss, "Material", MATERIAL); - print(ss, "Imbalance", IMBALANCE); - print(ss, "Pawns", PAWN); - print(ss, "Knights", KNIGHT); - print(ss, "Bishops", BISHOP); - print(ss, "Rooks", ROOK); - print(ss, "Queens", QUEEN); - print(ss, "Mobility", MOBILITY); - print(ss, "King safety", KING); - print(ss, "Threats", THREAT); - print(ss, "Passed pawns", PASSED); - print(ss, "Space", SPACE); + // In case of tracing add all single evaluation terms + if (DoTrace) + { + Trace::add(MATERIAL, pos.psq_score()); + Trace::add(IMBALANCE, me->imbalance()); + Trace::add(PAWN, ei.pi->pawns_score()); + Trace::add(MOBILITY, mobility[WHITE] * Weights[Mobility] + , mobility[BLACK] * Weights[Mobility]); + Trace::add(SPACE, evaluate_space(pos, ei) * Weights[Space] + , evaluate_space(pos, ei) * Weights[Space]); + Trace::add(TOTAL, score); + } - ss << "----------------+-------------+-------------+-------------\n"; - print(ss, "Total", TOTAL); + return (pos.side_to_move() == WHITE ? v : -v) + Eval::Tempo; // Side to move point of view +} - ss << "\nTotal Evaluation: " << to_cp(v) << " (white side)\n"; +// Explicit template instantiations +template Value Eval::evaluate(const Position&); +template Value Eval::evaluate(const Position&); - return ss.str(); - } -} // namespace +/// 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) { -namespace Eval { + std::memset(scores, 0, sizeof(scores)); - /// 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. + Value v = evaluate(pos); + v = pos.side_to_move() == WHITE ? v : -v; // White's point of view - Value evaluate(const Position& pos) { - return do_evaluate(pos); - } + 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"; - /// 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); - } + return ss.str(); +} - /// init() computes evaluation weights from the corresponding UCI parameters - /// and setup king tables. +/// init() computes evaluation weights, usually at startup - void init() { +void Eval::init() { - const double MaxSlope = 30; - const double Peak = 1280; + const int MaxSlope = 8700; + const int Peak = 1280000; + int t = 0; - for (int t = 0, i = 1; i < 100; ++i) - { - t = int(std::min(Peak, std::min(0.4 * i * i, t + MaxSlope))); - KingDanger[i] = apply_weight(make_score(t, 0), Weights[KingSafety]); - } + for (int i = 0; i < 400; ++i) + { + t = std::min(Peak, std::min(i * i * 27, t + MaxSlope)); + KingDanger[i] = make_score(t / 1000, 0) * Weights[KingSafety]; } - -} // namespace Eval +}