X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.h;h=b472c3fd266c362cd0b032448908475b20291ec2;hp=9992c0b71c51ba55dafde449f61c75f6b4b2b929;hb=6ed81f09ffa513f0938c1a16fa4edd55e552c178;hpb=0fcda095df1caa860e8e3f3a714d5545ec9dc122 diff --git a/src/material.h b/src/material.h index 9992c0b7..b472c3fd 100644 --- a/src/material.h +++ b/src/material.h @@ -1,7 +1,8 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, 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 @@ -17,125 +18,56 @@ along with this program. If not, see . */ -#if !defined(MATERIAL_H_INCLUDED) +#ifndef MATERIAL_H_INCLUDED #define MATERIAL_H_INCLUDED #include "endgame.h" +#include "misc.h" #include "position.h" -#include "tt.h" +#include "types.h" -const int MaterialTableSize = 1024; +namespace Material { -/// MaterialInfo is a class which contains various information about a -/// material configuration. It contains a material balance evaluation, -/// a function pointer to a special endgame evaluation function (which in -/// most cases is NULL, meaning that the standard evaluation function will -/// be used), and "scale factors" for black and white. +/// Material::Entry contains various information about a material configuration. +/// It contains a material imbalance evaluation, a function pointer to a special +/// endgame evaluation function (which in most cases is NULL, meaning that the +/// standard evaluation function will be used), and scale factors. /// -/// The scale factors are used to scale the evaluation score up or down. -/// For instance, in KRB vs KR endgames, the score is scaled down by a factor -/// of 4, which will result in scores of absolute value less than one pawn. - -class MaterialInfo { - - friend class MaterialInfoTable; - -public: - Score material_value() const; - ScaleFactor scale_factor(const Position& pos, Color c) const; - int space_weight() const; - Phase game_phase() const; - bool specialized_eval_exists() const; - Value evaluate(const Position& pos) const; +/// The scale factors are used to scale the evaluation score up or down. For +/// instance, in KRB vs KR endgames, the score is scaled down by a factor of 4, +/// which will result in scores of absolute value less than one pawn. + +struct Entry { + + Score imbalance() const { return make_score(value, value); } + Phase game_phase() const { return gamePhase; } + bool specialized_eval_exists() const { return evaluationFunction != nullptr; } + Value evaluate(const Position& pos) const { return (*evaluationFunction)(pos); } + + // scale_factor takes a position and a color as input and returns a scale factor + // for the given color. We have to provide the position in addition to the color + // because the scale factor may also be a function which should be applied to + // the position. For instance, in KBP vs K endgames, the scaling function looks + // for rook pawns and wrong-colored bishops. + ScaleFactor scale_factor(const Position& pos, Color c) const { + ScaleFactor sf = scalingFunction[c] ? (*scalingFunction[c])(pos) + : SCALE_FACTOR_NONE; + return sf != SCALE_FACTOR_NONE ? sf : ScaleFactor(factor[c]); + } -private: Key key; + const EndgameBase* evaluationFunction; + const EndgameBase* scalingFunction[COLOR_NB]; // Could be one for each + // side (e.g. KPKP, KBPsK) int16_t value; - uint8_t factor[2]; - EndgameEvaluationFunctionBase* evaluationFunction; - EndgameScalingFunctionBase* scalingFunction[2]; - int spaceWeight; + uint8_t factor[COLOR_NB]; Phase gamePhase; }; -/// The MaterialInfoTable class represents a pawn hash table. The most important -/// method is get_material_info, which returns a pointer to a MaterialInfo object. -class EndgameFunctions; - -class MaterialInfoTable : public SimpleHash { -public: - MaterialInfoTable(); - ~MaterialInfoTable(); - MaterialInfo* get_material_info(const Position& pos); - static Phase game_phase(const Position& pos); -private: - EndgameFunctions* funcs; -}; - - -/// MaterialInfo::material_value simply returns the material balance -/// evaluation that is independent from game phase. - -inline Score MaterialInfo::material_value() const { - - return make_score(value, value); -} - - -/// MaterialInfo::scale_factor takes a position and a color as input, and -/// returns a scale factor for the given color. We have to provide the -/// position in addition to the color, because the scale factor need not -/// to be a constant: It can also be a function which should be applied to -/// the position. For instance, in KBP vs K endgames, a scaling function -/// which checks for draws with rook pawns and wrong-colored bishops. - -inline ScaleFactor MaterialInfo::scale_factor(const Position& pos, Color c) const { - - if (scalingFunction[c] != NULL) - { - ScaleFactor sf = scalingFunction[c]->apply(pos); - if (sf != SCALE_FACTOR_NONE) - return sf; - } - return ScaleFactor(factor[c]); -} - - -/// MaterialInfo::space_weight() simply returns the weight for the space -/// evaluation for this material configuration. - -inline int MaterialInfo::space_weight() const { - - return spaceWeight; -} - - -/// MaterialInfo::game_phase() returns the game phase according -/// to this material configuration. - -inline Phase MaterialInfo::game_phase() const { - - return gamePhase; -} - - -/// MaterialInfo::specialized_eval_exists decides whether there is a -/// specialized evaluation function for the current material configuration, -/// or if the normal evaluation function should be used. - -inline bool MaterialInfo::specialized_eval_exists() const { - - return evaluationFunction != NULL; -} - - -/// MaterialInfo::evaluate applies a specialized evaluation function -/// to a given position object. It should only be called when -/// specialized_eval_exists() returns 'true'. +typedef HashTable Table; -inline Value MaterialInfo::evaluate(const Position& pos) const { +Entry* probe(const Position& pos); - return evaluationFunction->apply(pos); -} +} // namespace Material -#endif // !defined(MATERIAL_H_INCLUDED) +#endif // #ifndef MATERIAL_H_INCLUDED