X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=fc2f4b7cf35e454687c4ec2ead6a7276ea0546bd;hp=9a20292bd010fda49a36b7ff3e060109eda749f5;hb=cb9399445f5ce6f9e209a7ae35ad00ce45dc9c0d;hpb=76bed11f7b79d939c250c02d73d0c1e2628e7a17 diff --git a/src/material.cpp b/src/material.cpp index 9a20292b..fc2f4b7c 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 @@ -37,10 +37,15 @@ using namespace std; namespace { + // Values modified by Joona Kiiski + 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] = { 1617, -162, -1172, -190, 105, 26 }; + + const int LinearCoefficients[6] = { 1617, -162, -1172, -190, 105, 26 }; const int QuadraticCoefficientsSameColor[][6] = { { 7, 7, 7, 7, 7, 7 }, { 39, 2, 7, 7, 7, 7 }, { 35, 271, -4, 7, 7, 7 }, @@ -50,17 +55,40 @@ namespace { { 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 } }; - // 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 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; + + // 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(0) + && 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; + } } @@ -129,6 +157,22 @@ 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 @@ -151,39 +195,33 @@ 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. 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) + else if (is_KXK(pos) || is_KXK(pos)) { - mi->evaluationFunction = &EvaluateKXK; + mi->evaluationFunction = is_KXK(pos) ? &EvaluateKXK[WHITE] : &EvaluateKXK[BLACK]; return mi; } - else if ( pos.non_pawn_material(WHITE) == Value(0) - && pos.piece_count(WHITE, PAWN) == 0 - && pos.non_pawn_material(BLACK) >= RookValueMidgame) - { - mi->evaluationFunction = &EvaluateKKX; - return mi; - } - else if ( pos.pieces() == EmptyBoardBB - && pos.pieces() == EmptyBoardBB - && pos.pieces() == 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. Note that the case KmmK is already handled by KXK. - assert((pos.pieces(WHITE) | pos.pieces(WHITE))); - assert((pos.pieces(BLACK) | pos.pieces(BLACK))); + 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; } } @@ -206,48 +244,36 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { // 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] = &ScaleKBPsK; - - if ( pos.non_pawn_material(BLACK) == BishopValueMidgame - && pos.piece_count(BLACK, BISHOP) == 1 - && pos.piece_count(BLACK, PAWN) >= 1) - 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] = &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] = &ScaleKRPsKQ; + 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(0)) { 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) { // 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; + mi->scalingFunction[WHITE] = &ScaleKPKP[WHITE]; + mi->scalingFunction[BLACK] = &ScaleKPKP[BLACK]; } } @@ -269,8 +295,8 @@ 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) { @@ -304,25 +330,27 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) { 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. - 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; @@ -348,7 +376,6 @@ EndgameFunctions::EndgameFunctions() { add >("KBPPKB"); add >("KBPKN"); add >("KRPPKRP"); - add >("KRPPKRP"); } EndgameFunctions::~EndgameFunctions() {