X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=ffc549ca6962bb637e9d23059bb991a76f792563;hp=8380ab8f6219c48a9b53e78d91e20d7b47a99fb5;hb=94b9c65e09b5d396bebb29b62d9979139b5fbdfa;hpb=044ad593b3c9fa8ab70f9b2ebfc2c36ce398eb5f diff --git a/src/material.cpp b/src/material.cpp index 8380ab8f..ffc549ca 100644 --- a/src/material.cpp +++ b/src/material.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) 2008-2010 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 @@ -28,7 +28,8 @@ #include "material.h" -using std::string; +using namespace std; + //// //// Local definitions @@ -37,32 +38,59 @@ using std::string; namespace { // Values modified by Joona Kiiski - const Value BishopPairMidgameBonus = Value(109); - const Value BishopPairEndgameBonus = Value(97); + const Value MidgameLimit = Value(15581); + const Value EndgameLimit = Value(3998); // Polynomial material balance parameters const Value RedundantQueenPenalty = Value(320); const Value RedundantRookPenalty = Value(554); - const int LinearCoefficients[6] = { 1709, -137, -1185, -166, 141, 59 }; + + const int LinearCoefficients[6] = { 1617, -162, -1172, -190, 105, 26 }; const int QuadraticCoefficientsSameColor[][6] = { - { 0, 0, 0, 0, 0, 0 }, { 33, -6, 0, 0, 0, 0 }, { 29, 269, -12, 0, 0, 0 }, - { 0, 19, -4, 0, 0, 0 }, { -35, -10, 40, 95, 50, 0 }, { 52, 23, 78, 144, -11, -33 } }; + { 7, 7, 7, 7, 7, 7 }, { 39, 2, 7, 7, 7, 7 }, { 35, 271, -4, 7, 7, 7 }, + { 7, 25, 4, 7, 7, 7 }, { -27, -2, 46, 100, 56, 7 }, { 58, 29, 83, 148, -3, -25 } }; const int QuadraticCoefficientsOppositeColor[][6] = { - { 0, 0, 0, 0, 0, 0 }, { -5, 0, 0, 0, 0, 0 }, { -33, 23, 0, 0, 0, 0 }, - { 17, 25, -3, 0, 0, 0 }, { 10, -2, -19, -67, 0, 0 }, { 69, 64, -41, 116, 137, 0 } }; - - // Unmapped endgame evaluation and scaling functions, these - // are accessed direcly and not through the function maps. - EvaluationFunction EvaluateKmmKm(WHITE); - EvaluationFunction EvaluateKXK(WHITE), EvaluateKKX(BLACK); - ScalingFunction ScaleKBPK(WHITE), ScaleKKBP(BLACK); - ScalingFunction ScaleKQKRP(WHITE), ScaleKRPKQ(BLACK); - ScalingFunction ScaleKPsK(WHITE), ScaleKKPs(BLACK); - ScalingFunction ScaleKPKPw(WHITE), ScaleKPKPb(BLACK); - - Key KNNKMaterialKey, KKNNMaterialKey; + { 41, 41, 41, 41, 41, 41 }, { 37, 41, 41, 41, 41, 41 }, { 10, 62, 41, 41, 41, 41 }, + { 57, 64, 39, 41, 41, 41 }, { 50, 40, 23, -22, 41, 41 }, { 106, 101, 3, 151, 171, 41 } }; + + typedef EndgameEvaluationFunctionBase EF; + typedef EndgameScalingFunctionBase SF; + typedef map EFMap; + typedef map SFMap; + + // Endgame evaluation and scaling functions accessed direcly and not through + // the function maps because correspond to more then one material hash key. + EvaluationFunction EvaluateKmmKm[] = { EvaluationFunction(WHITE), EvaluationFunction(BLACK) }; + EvaluationFunction EvaluateKXK[] = { EvaluationFunction(WHITE), EvaluationFunction(BLACK) }; + ScalingFunction ScaleKBPsK[] = { ScalingFunction(WHITE), ScalingFunction(BLACK) }; + ScalingFunction ScaleKQKRPs[] = { ScalingFunction(WHITE), ScalingFunction(BLACK) }; + ScalingFunction ScaleKPsK[] = { ScalingFunction(WHITE), ScalingFunction(BLACK) }; + ScalingFunction ScaleKPKP[] = { ScalingFunction(WHITE), ScalingFunction(BLACK) }; + + // Helper templates used to detect a given material distribution + template bool is_KXK(const Position& pos) { + const Color Them = (Us == WHITE ? BLACK : WHITE); + return pos.non_pawn_material(Them) == VALUE_ZERO + && pos.piece_count(Them, PAWN) == 0 + && pos.non_pawn_material(Us) >= RookValueMidgame; + } + + template bool is_KBPsK(const Position& pos) { + return pos.non_pawn_material(Us) == BishopValueMidgame + && pos.piece_count(Us, BISHOP) == 1 + && pos.piece_count(Us, PAWN) >= 1; + } + + template bool is_KQKRPs(const Position& pos) { + const Color Them = (Us == WHITE ? BLACK : WHITE); + return pos.piece_count(Us, PAWN) == 0 + && pos.non_pawn_material(Us) == QueenValueMidgame + && pos.piece_count(Us, QUEEN) == 1 + && pos.piece_count(Them, ROOK) == 1 + && pos.piece_count(Them, PAWN) >= 1; + } } @@ -70,11 +98,10 @@ namespace { //// Classes //// -typedef EndgameEvaluationFunctionBase EF; -typedef EndgameScalingFunctionBase SF; - -/// See header for a class description. It is declared here to avoid -/// to include in the header file. +/// EndgameFunctions class stores endgame evaluation and scaling functions +/// in two std::map. Because STL library is not guaranteed to be thread +/// safe even for read access, the maps, although with identical content, +/// are replicated for each thread. This is faster then using locks. class EndgameFunctions { public: @@ -88,46 +115,39 @@ private: static Key buildKey(const string& keyCode); static const string swapColors(const string& keyCode); - std::map EEFmap; - std::map ESFmap; + // Here we store two maps, for evaluate and scaling functions... + pair maps; - // Maps accessing functions for const and non-const references - template const std::map& map() const { return EEFmap; } - template std::map& map() { return EEFmap; } + // ...and here is the accessing template function + template const map& get() const; }; // Explicit specializations of a member function shall be declared in // the namespace of which the class template is a member. -template<> const std::map& -EndgameFunctions::map() const { return ESFmap; } - -template<> std::map& -EndgameFunctions::map() { return ESFmap; } +template<> const EFMap& EndgameFunctions::get() const { return maps.first; } +template<> const SFMap& EndgameFunctions::get() const { return maps.second; } //// //// Functions //// - -/// Constructor for the MaterialInfoTable class +/// MaterialInfoTable c'tor and d'tor, called once by each thread MaterialInfoTable::MaterialInfoTable(unsigned int numOfEntries) { size = numOfEntries; entries = new MaterialInfo[size]; funcs = new EndgameFunctions(); + if (!entries || !funcs) { - std::cerr << "Failed to allocate " << (numOfEntries * sizeof(MaterialInfo)) - << " bytes for material hash table." << std::endl; + cerr << "Failed to allocate " << numOfEntries * sizeof(MaterialInfo) + << " bytes for material hash table." << endl; Application::exit_with_failure(); } } - -/// Destructor for the MaterialInfoTable class - MaterialInfoTable::~MaterialInfoTable() { delete funcs; @@ -135,6 +155,23 @@ MaterialInfoTable::~MaterialInfoTable() { } +/// MaterialInfoTable::game_phase() calculates the phase given the current +/// position. Because the phase is strictly a function of the material, it +/// is stored in MaterialInfo. + +Phase MaterialInfoTable::game_phase(const Position& pos) { + + Value npm = pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK); + + if (npm >= MidgameLimit) + return PHASE_MIDGAME; + + if (npm <= EndgameLimit) + return PHASE_ENDGAME; + + return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit)); +} + /// MaterialInfoTable::get_material_info() takes a position object as input, /// computes or looks up a MaterialInfo object, and returns a pointer to it. /// If the material configuration is not already present in the table, it @@ -144,7 +181,7 @@ MaterialInfoTable::~MaterialInfoTable() { MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { Key key = pos.get_material_key(); - int index = key & (size - 1); + unsigned index = unsigned(key & (size - 1)); MaterialInfo* mi = entries + index; // If mi->key matches the position's material hash key, it means that we @@ -157,13 +194,8 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { mi->clear(); mi->key = key; - // A special case before looking for a specialized evaluation function - // KNN vs K is a draw. - if (key == KNNKMaterialKey || key == KKNNMaterialKey) - { - mi->factor[WHITE] = mi->factor[BLACK] = 0; - return mi; - } + // Store game phase + mi->gamePhase = MaterialInfoTable::game_phase(pos); // Let's look if we have a specialized evaluation function for this // particular material configuration. First we look for a fixed @@ -171,33 +203,25 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { if ((mi->evaluationFunction = funcs->get(key)) != NULL) return mi; - else if ( pos.non_pawn_material(BLACK) == Value(0) - && pos.piece_count(BLACK, PAWN) == 0 - && pos.non_pawn_material(WHITE) >= RookValueMidgame) - { - mi->evaluationFunction = &EvaluateKXK; - return mi; - } - else if ( pos.non_pawn_material(WHITE) == Value(0) - && pos.piece_count(WHITE, PAWN) == 0 - && pos.non_pawn_material(BLACK) >= RookValueMidgame) + if (is_KXK(pos) || is_KXK(pos)) { - mi->evaluationFunction = &EvaluateKKX; + mi->evaluationFunction = is_KXK(pos) ? &EvaluateKXK[WHITE] : &EvaluateKXK[BLACK]; return mi; } - else if ( pos.pawns() == EmptyBoardBB - && pos.rooks() == EmptyBoardBB - && pos.queens() == EmptyBoardBB) + + if ( pos.pieces(PAWN) == EmptyBoardBB + && pos.pieces(ROOK) == EmptyBoardBB + && pos.pieces(QUEEN) == EmptyBoardBB) { - // Minor piece endgame with at least one minor piece per side, - // and no pawns. - assert(pos.knights(WHITE) | pos.bishops(WHITE)); - assert(pos.knights(BLACK) | pos.bishops(BLACK)); + // Minor piece endgame with at least one minor piece per side and + // no pawns. Note that the case KmmK is already handled by KXK. + assert((pos.pieces(KNIGHT, WHITE) | pos.pieces(BISHOP, WHITE))); + assert((pos.pieces(KNIGHT, BLACK) | pos.pieces(BISHOP, BLACK))); if ( pos.piece_count(WHITE, BISHOP) + pos.piece_count(WHITE, KNIGHT) <= 2 && pos.piece_count(BLACK, BISHOP) + pos.piece_count(BLACK, KNIGHT) <= 2) { - mi->evaluationFunction = &EvaluateKmmKm; + mi->evaluationFunction = &EvaluateKmmKm[WHITE]; return mi; } } @@ -205,10 +229,8 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { // OK, we didn't find any special evaluation function for the current // material configuration. Is there a suitable scaling function? // - // The code below is rather messy, and it could easily get worse later, - // if we decide to add more special cases. We face problems when there - // are several conflicting applicable scaling functions and we need to - // decide which one to use. + // We face problems when there are several conflicting applicable + // scaling functions and we need to decide which one to use. SF* sf; if ((sf = funcs->get(key)) != NULL) @@ -217,46 +239,39 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { return mi; } - if ( pos.non_pawn_material(WHITE) == BishopValueMidgame - && pos.piece_count(WHITE, BISHOP) == 1 - && pos.piece_count(WHITE, PAWN) >= 1) - mi->scalingFunction[WHITE] = &ScaleKBPK; - - if ( pos.non_pawn_material(BLACK) == BishopValueMidgame - && pos.piece_count(BLACK, BISHOP) == 1 - && pos.piece_count(BLACK, PAWN) >= 1) - mi->scalingFunction[BLACK] = &ScaleKKBP; - - if ( pos.piece_count(WHITE, PAWN) == 0 - && pos.non_pawn_material(WHITE) == QueenValueMidgame - && pos.piece_count(WHITE, QUEEN) == 1 - && pos.piece_count(BLACK, ROOK) == 1 - && pos.piece_count(BLACK, PAWN) >= 1) - mi->scalingFunction[WHITE] = &ScaleKQKRP; - - else if ( pos.piece_count(BLACK, PAWN) == 0 - && pos.non_pawn_material(BLACK) == QueenValueMidgame - && pos.piece_count(BLACK, QUEEN) == 1 - && pos.piece_count(WHITE, ROOK) == 1 - && pos.piece_count(WHITE, PAWN) >= 1) - mi->scalingFunction[BLACK] = &ScaleKRPKQ; - - if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == Value(0)) + // Generic scaling functions that refer to more then one material + // distribution. Should be probed after the specialized ones. + // Note that these ones don't return after setting the function. + if (is_KBPsK(pos)) + mi->scalingFunction[WHITE] = &ScaleKBPsK[WHITE]; + + if (is_KBPsK(pos)) + mi->scalingFunction[BLACK] = &ScaleKBPsK[BLACK]; + + if (is_KQKRPs(pos)) + mi->scalingFunction[WHITE] = &ScaleKQKRPs[WHITE]; + + else if (is_KQKRPs(pos)) + mi->scalingFunction[BLACK] = &ScaleKQKRPs[BLACK]; + + if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == VALUE_ZERO) { if (pos.piece_count(BLACK, PAWN) == 0) { assert(pos.piece_count(WHITE, PAWN) >= 2); - mi->scalingFunction[WHITE] = &ScaleKPsK; + mi->scalingFunction[WHITE] = &ScaleKPsK[WHITE]; } else if (pos.piece_count(WHITE, PAWN) == 0) { assert(pos.piece_count(BLACK, PAWN) >= 2); - mi->scalingFunction[BLACK] = &ScaleKKPs; + mi->scalingFunction[BLACK] = &ScaleKPsK[BLACK]; } else if (pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1) { - mi->scalingFunction[WHITE] = &ScaleKPKPw; - mi->scalingFunction[BLACK] = &ScaleKPKPb; + // This is a special case because we set scaling functions + // for both colors instead of only one. + mi->scalingFunction[WHITE] = &ScaleKPKP[WHITE]; + mi->scalingFunction[BLACK] = &ScaleKPKP[BLACK]; } } @@ -273,11 +288,13 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { } // Evaluate the material balance - - const int bishopsPair_count[2] = { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(BLACK, BISHOP) > 1 }; + const int pieceCount[2][6] = { { pos.piece_count(WHITE, BISHOP) > 1, pos.piece_count(WHITE, PAWN), pos.piece_count(WHITE, KNIGHT), + pos.piece_count(WHITE, BISHOP), pos.piece_count(WHITE, ROOK), pos.piece_count(WHITE, QUEEN) }, + { pos.piece_count(BLACK, BISHOP) > 1, pos.piece_count(BLACK, PAWN), pos.piece_count(BLACK, KNIGHT), + pos.piece_count(BLACK, BISHOP), pos.piece_count(BLACK, ROOK), pos.piece_count(BLACK, QUEEN) } }; Color c, them; - int sign; - int matValue = 0; + int sign, pt1, pt2, pc; + int v, vv, matValue = 0; for (c = WHITE, sign = 1; c <= BLACK; c++, sign = -sign) { @@ -307,50 +324,42 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { // Redundancy of major pieces, formula based on Kaufman's paper // "The Evaluation of Material Imbalances in Chess" // http://mywebpages.comcast.net/danheisman/Articles/evaluation_of_material_imbalance.htm - if (pos.piece_count(c, ROOK) >= 1) - matValue -= sign * ((pos.piece_count(c, ROOK) - 1) * RedundantRookPenalty + pos.piece_count(c, QUEEN) * RedundantQueenPenalty); + if (pieceCount[c][ROOK] >= 1) + matValue -= sign * ((pieceCount[c][ROOK] - 1) * RedundantRookPenalty + pieceCount[c][QUEEN] * RedundantQueenPenalty); + + them = opposite_color(c); + v = 0; // Second-degree polynomial material imbalance by Tord Romstad // // We use NO_PIECE_TYPE as a place holder for the bishop pair "extended piece", // this allow us to be more flexible in defining bishop pair bonuses. - them = opposite_color(c); - for (PieceType pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++) + for (pt1 = PIECE_TYPE_NONE; pt1 <= QUEEN; pt1++) { - int c1, c2, c3; - c1 = sign * (pt1 != NO_PIECE_TYPE ? pos.piece_count(c, pt1) : bishopsPair_count[c]); - if (!c1) + pc = pieceCount[c][pt1]; + if (!pc) continue; - matValue += c1 * LinearCoefficients[pt1]; + vv = LinearCoefficients[pt1]; - for (PieceType pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++) - { - c2 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(c, pt2) : bishopsPair_count[c]); - c3 = (pt2 != NO_PIECE_TYPE ? pos.piece_count(them, pt2) : bishopsPair_count[them]); - matValue += c1 * c2 * QuadraticCoefficientsSameColor[pt1][pt2]; - matValue += c1 * c3 * QuadraticCoefficientsOppositeColor[pt1][pt2]; - } + for (pt2 = PIECE_TYPE_NONE; pt2 <= pt1; pt2++) + vv += pieceCount[c][pt2] * QuadraticCoefficientsSameColor[pt1][pt2] + + pieceCount[them][pt2] * QuadraticCoefficientsOppositeColor[pt1][pt2]; + + v += pc * vv; } + matValue += sign * v; } - mi->value = int16_t(matValue / 16); return mi; } -/// EndgameFunctions member definitions. This class is used to store the maps -/// of end game and scaling functions that MaterialInfoTable will query for -/// each key. The maps are constant and are populated only at construction, -/// but are per-thread instead of globals to avoid expensive locks needed -/// because std::map is not guaranteed to be thread-safe even if accessed -/// only for a lookup. +/// EndgameFunctions member definitions. EndgameFunctions::EndgameFunctions() { - KNNKMaterialKey = buildKey("KNNK"); - KKNNMaterialKey = buildKey("KKNN"); - + add >("KNNK"); add >("KPK"); add >("KBNK"); add >("KRKP"); @@ -365,16 +374,15 @@ EndgameFunctions::EndgameFunctions() { add >("KBPPKB"); add >("KBPKN"); add >("KRPPKRP"); - add >("KRPPKRP"); } EndgameFunctions::~EndgameFunctions() { - for (std::map::iterator it = EEFmap.begin(); it != EEFmap.end(); ++it) - delete (*it).second; + for (EFMap::const_iterator it = maps.first.begin(); it != maps.first.end(); ++it) + delete it->second; - for (std::map::iterator it = ESFmap.begin(); it != ESFmap.end(); ++it) - delete (*it).second; + for (SFMap::const_iterator it = maps.second.begin(); it != maps.second.end(); ++it) + delete it->second; } Key EndgameFunctions::buildKey(const string& keyCode) { @@ -382,20 +390,20 @@ Key EndgameFunctions::buildKey(const string& keyCode) { assert(keyCode.length() > 0 && keyCode[0] == 'K'); assert(keyCode.length() < 8); - std::stringstream s; + stringstream s; bool upcase = false; - // Build up a fen substring with the given pieces, note - // that the fen string could be of an illegal position. + // Build up a fen string with the given pieces, note that + // the fen string could be of an illegal position. for (size_t i = 0; i < keyCode.length(); i++) { if (keyCode[i] == 'K') upcase = !upcase; - s << char(upcase? toupper(keyCode[i]) : tolower(keyCode[i])); + s << char(upcase ? toupper(keyCode[i]) : tolower(keyCode[i])); } - s << 8 - keyCode.length() << "/8/8/8/8/8/8/8 w -"; - return Position(s.str()).get_material_key(); + s << 8 - keyCode.length() << "/8/8/8/8/8/8/8 w - -"; + return Position(s.str(), 0).get_material_key(); } const string EndgameFunctions::swapColors(const string& keyCode) { @@ -409,14 +417,15 @@ template void EndgameFunctions::add(const string& keyCode) { typedef typename T::Base F; + typedef map M; - map().insert(std::pair(buildKey(keyCode), new T(WHITE))); - map().insert(std::pair(buildKey(swapColors(keyCode)), new T(BLACK))); + const_cast(get()).insert(pair(buildKey(keyCode), new T(WHITE))); + const_cast(get()).insert(pair(buildKey(swapColors(keyCode)), new T(BLACK))); } template T* EndgameFunctions::get(Key key) const { - typename std::map::const_iterator it(map().find(key)); - return (it != map().end() ? it->second : NULL); + typename map::const_iterator it = get().find(key); + return it != get().end() ? it->second : NULL; }