/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2018 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
#define ENDGAME_H_INCLUDED
#include <map>
+#include <memory>
#include <string>
+#include <type_traits>
+#include <utility>
#include "position.h"
#include "types.h"
-/// EndgameType lists all supported endgames
+/// EndgameCode lists all supported endgame functions by corresponding codes
-enum EndgameType {
-
- // Evaluation functions
+enum EndgameCode {
+ EVALUATION_FUNCTIONS,
KNNK, // KNN vs K
KXK, // Generic "mate lone king" eval
KBNK, // KBN vs K
KRKN, // KR vs KN
KQKP, // KQ vs KP
KQKR, // KQ vs KR
- KBBKN, // KBB vs KN
- KmmKm, // K and two minors vs K and one or two minors
-
- // Scaling functions
- SCALE_FUNS,
-
- KBPsK, // KB+pawns vs K
- KQKRPs, // KQ vs KR+pawns
+ SCALING_FUNCTIONS,
+ 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, // King and pawns vs king
+ KPsK, // K and pawns vs K
KBPKB, // KBP vs KB
KBPPKB, // KBPP vs KB
KBPKN, // KBP vs KN
};
-/// Endgame functions can be of two types according if return a Value or a
-/// ScaleFactor. Type eg_fun<int>::type equals to either ScaleFactor or Value
-/// depending if the template parameter is 0 or 1.
-
-template<int> struct eg_fun { typedef Value type; };
-template<> struct eg_fun<1> { typedef ScaleFactor type; };
+/// Endgame functions can be of two types depending on whether they return a
+/// Value or a ScaleFactor.
+template<EndgameCode E> using
+eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
-/// Base and derived templates for endgame evaluation and scaling functions
+/// Base and derived functors for endgame evaluation and scaling functions
template<typename T>
struct EndgameBase {
- virtual ~EndgameBase() {}
- virtual Color color() const = 0;
+ explicit EndgameBase(Color c) : strongSide(c), weakSide(~c) {}
+ virtual ~EndgameBase() = default;
virtual T operator()(const Position&) const = 0;
+
+ const Color strongSide, weakSide;
};
-template<EndgameType E, typename T = typename eg_fun<(E > SCALE_FUNS)>::type>
+template<EndgameCode E, typename T = eg_type<E>>
struct Endgame : public EndgameBase<T> {
- explicit Endgame(Color c) : strongerSide(c), weakerSide(~c) {}
- Color color() const { return strongerSide; }
- T operator()(const Position&) const;
-
-private:
- Color strongerSide, weakerSide;
+ explicit Endgame(Color c) : EndgameBase<T>(c) {}
+ T operator()(const Position&) const override;
};
-/// Endgames class stores in two std::map the pointers to endgame evaluation
-/// and scaling base objects. Then we use polymorphism to invoke the actual
-/// endgame function calling its operator() that is virtual.
+/// 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().
class Endgames {
- typedef std::map<Key, EndgameBase<eg_fun<0>::type>*> M1;
- typedef std::map<Key, EndgameBase<eg_fun<1>::type>*> M2;
+ template<typename T> using Ptr = std::unique_ptr<EndgameBase<T>>;
+ template<typename T> using Map = std::map<Key, Ptr<T>>;
+
+ template<typename T>
+ Map<T>& map() {
+ return std::get<std::is_same<T, ScaleFactor>::value>(maps);
+ }
- M1 m1;
- M2 m2;
+ template<EndgameCode E, typename T = eg_type<E>, typename P = Ptr<T>>
+ void add(const std::string& code) {
- M1& map(M1::mapped_type) { return m1; }
- M2& map(M2::mapped_type) { return m2; }
+ StateInfo st;
+ map<T>()[Position().set(code, WHITE, &st).material_key()] = P(new Endgame<E>(WHITE));
+ map<T>()[Position().set(code, BLACK, &st).material_key()] = P(new Endgame<E>(BLACK));
+ }
- template<EndgameType E> void add(const std::string& code);
+ std::pair<Map<Value>, Map<ScaleFactor>> maps;
public:
Endgames();
- ~Endgames();
- template<typename T> T probe(Key key, T& eg)
- { return eg = map(eg).count(key) ? map(eg)[key] : NULL; }
+ template<typename T>
+ EndgameBase<T>* probe(Key key) {
+ return map<T>().count(key) ? map<T>()[key].get() : nullptr;
+ }
};
#endif // #ifndef ENDGAME_H_INCLUDED