X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=f0ee5f682d02cada44957745849684613f3e4196;hp=27ea5923b492fc9caeb548a29e8dab6c1369da91;hb=6b7efa0cd14b73416c9030462f79a02bbfc7ad2c;hpb=339bb8a524a0a6af093b383da9f61b31504be9fe diff --git a/src/material.cpp b/src/material.cpp index 27ea5923..f0ee5f68 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 @@ -30,6 +30,7 @@ using namespace std; + //// //// Local definitions //// @@ -37,30 +38,34 @@ using namespace std; 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 } }; + { 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 } }; - // Unmapped endgame evaluation and scaling functions, these + // Named 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 ScaleKBPsK(WHITE), ScaleKKBPs(BLACK); + ScalingFunction ScaleKQKRPs(WHITE), ScaleKRPsKQ(BLACK); ScalingFunction ScaleKPsK(WHITE), ScaleKKPs(BLACK); ScalingFunction ScaleKPKPw(WHITE), ScaleKPKPb(BLACK); + + typedef EndgameEvaluationFunctionBase EF; + typedef EndgameScalingFunctionBase SF; } @@ -68,11 +73,10 @@ 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: @@ -86,10 +90,10 @@ private: static Key buildKey(const string& keyCode); static const string swapColors(const string& keyCode); - // Here we store two maps, one for evaluate and one for scaling + // Here we store two maps, for evaluate and scaling functions pair, map > maps; - // Maps accessing functions for const and non-const references + // Maps accessing functions returning const and non-const references template const map& get() const { return maps.first; } template map& get() { return maps.first; } }; @@ -107,25 +111,22 @@ EndgameFunctions::get() { 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) { - cerr << "Failed to allocate " << (numOfEntries * sizeof(MaterialInfo)) + 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; @@ -133,6 +134,22 @@ 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; + else 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 @@ -155,6 +172,9 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { mi->clear(); mi->key = key; + // 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 // configuration one, then a generic one if previous search failed. @@ -175,14 +195,14 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { mi->evaluationFunction = &EvaluateKKX; return mi; } - else if ( pos.pawns() == EmptyBoardBB - && pos.rooks() == EmptyBoardBB - && pos.queens() == EmptyBoardBB) + else 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) @@ -207,29 +227,32 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { return mi; } + // 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 ( pos.non_pawn_material(WHITE) == BishopValueMidgame && pos.piece_count(WHITE, BISHOP) == 1 && pos.piece_count(WHITE, PAWN) >= 1) - mi->scalingFunction[WHITE] = &ScaleKBPK; + mi->scalingFunction[WHITE] = &ScaleKBPsK; if ( pos.non_pawn_material(BLACK) == BishopValueMidgame && pos.piece_count(BLACK, BISHOP) == 1 && pos.piece_count(BLACK, PAWN) >= 1) - mi->scalingFunction[BLACK] = &ScaleKKBP; + mi->scalingFunction[BLACK] = &ScaleKKBPs; 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; + mi->scalingFunction[WHITE] = &ScaleKQKRPs; 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; + mi->scalingFunction[BLACK] = &ScaleKRPsKQ; if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == Value(0)) { @@ -245,6 +268,8 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { } else if (pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1) { + // This is a special case because we set scaling functions + // for both colors instead of only one. mi->scalingFunction[WHITE] = &ScaleKPKPw; mi->scalingFunction[BLACK] = &ScaleKPKPb; } @@ -268,8 +293,8 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { { 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) { @@ -279,7 +304,7 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { { if ( pos.non_pawn_material(c) == pos.non_pawn_material(opposite_color(c)) || pos.non_pawn_material(c) < RookValueMidgame) - mi->factor[c] = 0; + mi->factor[c] = SCALE_FACTOR_ZERO; else { switch (pos.piece_count(c, BISHOP)) { @@ -302,38 +327,35 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { 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 (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++) + for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++) { - int c1 = sign * pieceCount[c][pt1]; - if (!c1) + pc = pieceCount[c][pt1]; + if (!pc) continue; - matValue += c1 * LinearCoefficients[pt1]; + vv = LinearCoefficients[pt1]; - for (int pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++) - { - matValue += c1 * pieceCount[c][pt2] * QuadraticCoefficientsSameColor[pt1][pt2]; - matValue += c1 * pieceCount[them][pt2] * QuadraticCoefficientsOppositeColor[pt1][pt2]; - } + for (pt2 = NO_PIECE_TYPE; 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() { @@ -352,7 +374,6 @@ EndgameFunctions::EndgameFunctions() { add >("KBPPKB"); add >("KBPKN"); add >("KRPPKRP"); - add >("KRPPKRP"); } EndgameFunctions::~EndgameFunctions() { @@ -372,8 +393,8 @@ Key EndgameFunctions::buildKey(const string& keyCode) { 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')