+++ /dev/null
-/*
- 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
-
- Stockfish is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, either version 3 of the License, or
- (at your option) any later version.
-
- Stockfish is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-
-#if !defined(MATERIAL_H_INCLUDED)
-#define MATERIAL_H_INCLUDED
-
-////
-//// Includes
-////
-
-#include "endgame.h"
-#include "position.h"
-#include "scale.h"
-
-
-////
-//// Types
-////
-
-/// 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.
-///
-/// 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:
- MaterialInfo() : key(0) { clear(); }
-
- Value material_value() const;
- ScaleFactor scale_factor(const Position& pos, Color c) const;
- int space_weight() const;
- bool specialized_eval_exists() const;
- Value evaluate(const Position& pos) const;
-
-private:
- inline void clear();
-
- Key key;
- int16_t value;
- uint8_t factor[2];
- EndgameEvaluationFunctionBase* evaluationFunction;
- EndgameScalingFunctionBase* scalingFunction[2];
- int spaceWeight;
-};
-
-
-/// EndgameFunctions class stores the endgame evaluation functions std::map.
-/// Because STL library is not thread safe even for read access, the maps,
-/// although with identical content, are replicated for each thread. This
-/// is faster then using locks with an unique set of global maps.
-
-class EndgameFunctions;
-
-
-/// The MaterialInfoTable class represents a pawn hash table. It is basically
-/// just an array of MaterialInfo objects and a few methods for accessing these
-/// objects. The most important method is get_material_info, which looks up a
-/// position in the table and returns a pointer to a MaterialInfo object.
-
-class MaterialInfoTable {
-
-public:
- MaterialInfoTable(unsigned numOfEntries);
- ~MaterialInfoTable();
- MaterialInfo* get_material_info(const Position& pos);
-
-private:
- unsigned size;
- MaterialInfo* entries;
- EndgameFunctions* funcs;
-};
-
-
-////
-//// Inline functions
-////
-
-/// MaterialInfo::material_value simply returns the material balance
-/// evaluation that is independent from game phase.
-
-inline Value MaterialInfo::material_value() const {
-
- return Value(value);
-}
-
-
-/// MaterialInfo::clear() resets a MaterialInfo object to an empty state,
-/// with all slots at their default values but the key.
-
-inline void MaterialInfo::clear() {
-
- value = 0;
- factor[WHITE] = factor[BLACK] = uint8_t(SCALE_FACTOR_NORMAL);
- evaluationFunction = NULL;
- scalingFunction[WHITE] = scalingFunction[BLACK] = NULL;
- spaceWeight = 0;
-}
-
-
-/// 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::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'.
-
-inline Value MaterialInfo::evaluate(const Position& pos) const {
-
- return evaluationFunction->apply(pos);
-}
-
-#endif // !defined(MATERIAL_H_INCLUDED)
projects / stockfish / blobdiff