/*
- Glaurung, a UCI chess playing engine.
- Copyright (C) 2004-2008 Tord Romstad
+ Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+ Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
- Glaurung is free software: you can redistribute it and/or modify
+ 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.
-
- Glaurung is distributed in the hope that it will be useful,
+
+ 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(ENDGAME_H_INCLUDED)
+#ifndef ENDGAME_H_INCLUDED
#define ENDGAME_H_INCLUDED
-////
-//// Includes
-////
+#include <map>
+#include <string>
#include "position.h"
-#include "scale.h"
-#include "value.h"
-
+#include "types.h"
-////
-//// Types
-////
-/// Abstract base class for all special endgame evaluation functions:
+/// EndgameType lists all supported endgames
-class EndgameEvaluationFunction {
-public:
- EndgameEvaluationFunction(Color c);
- virtual ~EndgameEvaluationFunction() { }
+enum EndgameType {
- virtual Value apply(const Position &pos) =0;
+ // Evaluation functions
-protected:
- Color strongerSide, weakerSide;
-};
+ KNNK, // KNN vs K
+ KXK, // Generic "mate lone king" eval
+ KBNK, // KBN vs K
+ KPK, // KP vs K
+ KRKP, // KR vs KP
+ KRKB, // KR vs KB
+ KRKN, // KR vs KN
+ KQKP, // KQ vs KP
+ KQKR, // KQ vs KR
-/// Subclasses for various concrete endgames:
+ // Scaling functions
+ SCALING_FUNCTIONS,
-// Generic "mate lone king" eval:
-class KXKEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KXKEvaluationFunction(Color c);
- Value apply(const Position &pos);
+ KBPsK, // KB and pawns vs K
+ KQKRPs, // KQ vs KR and pawns
+ KRPKR, // KRP vs KR
+ KRPKB, // KRP vs KB
+ KRPPKRP, // KRPP vs KRP
+ KPsK, // K and pawns vs K
+ KBPKB, // KBP vs KB
+ KBPPKB, // KBPP vs KB
+ KBPKN, // KBP vs KN
+ KNPK, // KNP vs K
+ KNPKB, // KNP vs KB
+ KPKP // KP vs KP
};
-// KBN vs K:
-class KBNKEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KBNKEvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
-// KP vs K:
-class KPKEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KPKEvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
+/// Endgame functions can be of two types depending on whether they return a
+/// Value or a ScaleFactor. Type eg_fun<int>::type returns either ScaleFactor
+/// or Value depending on whether the template parameter is 0 or 1.
-// KR vs KP:
-class KRKPEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KRKPEvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
+template<int> struct eg_fun { typedef Value type; };
+template<> struct eg_fun<1> { typedef ScaleFactor type; };
-// KR vs KB:
-class KRKBEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KRKBEvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
-// KR vs KN:
-class KRKNEvaluationFunction : public EndgameEvaluationFunction {
-public:
- KRKNEvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
+/// Base and derived templates for endgame evaluation and scaling functions
-// KQ vs KR:
-class KQKREvaluationFunction : public EndgameEvaluationFunction {
-public:
- KQKREvaluationFunction(Color c);
- Value apply(const Position &pos);
-};
+template<typename T>
+struct EndgameBase {
+ virtual ~EndgameBase() {}
+ virtual Color strong_side() const = 0;
+ virtual T operator()(const Position&) const = 0;
+};
-/// Abstract base class for all evaluation scaling functions:
-class ScalingFunction {
-public:
- ScalingFunction(Color c);
- virtual ~ScalingFunction() { }
+template<EndgameType E, typename T = typename eg_fun<(E > SCALING_FUNCTIONS)>::type>
+struct Endgame : public EndgameBase<T> {
- virtual ScaleFactor apply(const Position &pos) =0;
+ explicit Endgame(Color c) : strongSide(c), weakSide(~c) {}
+ Color strong_side() const { return strongSide; }
+ T operator()(const Position&) const;
-protected:
- Color strongerSide, weakerSide;
+private:
+ const Color strongSide, weakSide;
};
-/// Subclasses for various concrete endgames:
+/// The Endgames class stores the pointers to endgame evaluation and scaling
+/// base objects in two std::map. We use polymorphism to invoke the actual
+/// endgame function by calling its virtual operator().
-// KBP vs K:
-class KBPKScalingFunction : public ScalingFunction {
-public:
- KBPKScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+class Endgames {
-// KQ vs KRP:
-class KQKRPScalingFunction: public ScalingFunction {
-public:
- KQKRPScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+ typedef std::map<Key, EndgameBase<eg_fun<0>::type>*> M1;
+ typedef std::map<Key, EndgameBase<eg_fun<1>::type>*> M2;
-// KRP vs KR:
-class KRPKRScalingFunction : public ScalingFunction {
-public:
- KRPKRScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+ M1 m1;
+ M2 m2;
-// KRPP vs KRP:
-class KRPPKRPScalingFunction : public ScalingFunction {
-public:
- KRPPKRPScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+ M1& map(M1::mapped_type) { return m1; }
+ M2& map(M2::mapped_type) { return m2; }
-// King and pawns vs king:
-class KPsKScalingFunction : public ScalingFunction {
-public:
- KPsKScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+ template<EndgameType E> void add(const std::string& code);
-// KBP vs KB:
-class KBPKBScalingFunction : public ScalingFunction {
public:
- KBPKBScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
-
-// KBP vs KN:
-class KBPKNScalingFunction : public ScalingFunction {
-public:
- KBPKNScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
+ Endgames();
+ ~Endgames();
-// KNP vs K:
-class KNPKScalingFunction : public ScalingFunction {
-public:
- KNPKScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
-};
-
-// KP vs KP:
-class KPKPScalingFunction : public ScalingFunction {
-public:
- KPKPScalingFunction(Color c);
- ScaleFactor apply(const Position &pos);
+ template<typename T> T probe(Key key, T& eg) {
+ return eg = map(eg).count(key) ? map(eg)[key] : NULL;
+ }
};
-
-////
-//// Constants and variables
-////
-
-// Generic "mate lone king" eval:
-extern KXKEvaluationFunction EvaluateKXK, EvaluateKKX;
-
-// KBN vs K:
-extern KBNKEvaluationFunction EvaluateKBNK, EvaluateKKBN;
-
-// KP vs K:
-extern KPKEvaluationFunction EvaluateKPK, EvaluateKKP;
-
-// KR vs KP:
-extern KRKPEvaluationFunction EvaluateKRKP, EvaluateKPKR;
-
-// KR vs KB:
-extern KRKBEvaluationFunction EvaluateKRKB, EvaluateKBKR;
-
-// KR vs KN:
-extern KRKNEvaluationFunction EvaluateKRKN, EvaluateKNKR;
-
-// KQ vs KR:
-extern KQKREvaluationFunction EvaluateKQKR, EvaluateKRKQ;
-
-// KBP vs K:
-extern KBPKScalingFunction ScaleKBPK, ScaleKKBP;
-
-// KQ vs KRP:
-extern KQKRPScalingFunction ScaleKQKRP, ScaleKRPKQ;
-
-// KRP vs KR:
-extern KRPKRScalingFunction ScaleKRPKR, ScaleKRKRP;
-
-// KRPP vs KRP:
-extern KRPPKRPScalingFunction ScaleKRPPKRP, ScaleKRPKRPP;
-
-// King and pawns vs king:
-extern KPsKScalingFunction ScaleKPsK, ScaleKKPs;
-
-// KBP vs KB:
-extern KBPKBScalingFunction ScaleKBPKB, ScaleKBKBP;
-
-// KBP vs KN:
-extern KBPKNScalingFunction ScaleKBPKN, ScaleKNKBP;
-
-// KNP vs K:
-extern KNPKScalingFunction ScaleKNPK, ScaleKKNP;
-
-// KP vs KP:
-extern KPKPScalingFunction ScaleKPKPw, ScaleKPKPb;
-
-
-////
-//// Prototypes
-////
-
-extern void init_bitbases();
-
-
-#endif // !defined(ENDGAME_H_INCLUDED)
+#endif // #ifndef ENDGAME_H_INCLUDED