2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
5 Copyright (C) 2015-2016 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
7 Stockfish is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
12 Stockfish is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
21 #ifndef ENDGAME_H_INCLUDED
22 #define ENDGAME_H_INCLUDED
27 #include <type_traits>
34 /// EndgameType lists all supported endgames
38 // Evaluation functions
41 KXK, // Generic "mate lone king" eval
54 KBPsK, // KB and pawns vs K
55 KQKRPs, // KQ vs KR and pawns
58 KRPPKRP, // KRPP vs KRP
59 KPsK, // K and pawns vs K
69 /// Endgame functions can be of two types depending on whether they return a
70 /// Value or a ScaleFactor.
71 template<EndgameType E> using
72 eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
75 /// Base and derived templates for endgame evaluation and scaling functions
80 virtual ~EndgameBase() = default;
81 virtual Color strong_side() const = 0;
82 virtual T operator()(const Position&) const = 0;
86 template<EndgameType E, typename T = eg_type<E>>
87 struct Endgame : public EndgameBase<T> {
89 explicit Endgame(Color c) : strongSide(c), weakSide(~c) {}
90 Color strong_side() const { return strongSide; }
91 T operator()(const Position&) const;
94 Color strongSide, weakSide;
98 /// The Endgames class stores the pointers to endgame evaluation and scaling
99 /// base objects in two std::map. We use polymorphism to invoke the actual
100 /// endgame function by calling its virtual operator().
104 template<typename T> using Map = std::map<Key, std::unique_ptr<EndgameBase<T>>>;
106 template<EndgameType E, typename T = eg_type<E>>
107 void add(const std::string& code);
111 return std::get<std::is_same<T, ScaleFactor>::value>(maps);
114 std::pair<Map<Value>, Map<ScaleFactor>> maps;
120 EndgameBase<T>* probe(Key key) {
121 return map<T>().count(key) ? map<T>()[key].get() : nullptr;
125 #endif // #ifndef ENDGAME_H_INCLUDED