/*
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) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2016 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
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-
-#if !defined(MATERIAL_H_INCLUDED)
+#ifndef MATERIAL_H_INCLUDED
#define MATERIAL_H_INCLUDED
-////
-//// Includes
-////
-
#include "endgame.h"
+#include "misc.h"
#include "position.h"
-#include "scale.h"
-
+#include "types.h"
-////
-//// Types
-////
+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:
- MaterialInfo() : key(0) { clear(); }
-
- Score 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();
+/// 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 {
+ return !scalingFunction[c]
+ || (*scalingFunction[c])(pos) == SCALE_FACTOR_NONE ? ScaleFactor(factor[c])
+ : (*scalingFunction[c])(pos);
+ }
Key key;
int16_t value;
- uint8_t factor[2];
- EndgameEvaluationFunctionBase* evaluationFunction;
- EndgameScalingFunctionBase* scalingFunction[2];
- int spaceWeight;
+ uint8_t factor[COLOR_NB];
+ EndgameBase<Value>* evaluationFunction;
+ EndgameBase<ScaleFactor>* scalingFunction[COLOR_NB]; // Could be one for each
+ // side (e.g. KPKP, KBPsKs)
+ Phase gamePhase;
};
-/// 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 EndgameFunctions;
-
-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 Score MaterialInfo::material_value() const {
-
- return make_score(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'.
+typedef HashTable<Entry, 8192> 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
projects / stockfish / blobdiff