Sync with master

[stockfish] / src / endgame.h

diff --git a/src/endgame.h b/src/endgame.h
index 4426ef186c5bacd4347bf94f712cbe08fef7a88a..cd05f0cd1b6273cfa91341d379bc36439d3271d5 100644 (file)
--- a/src/endgame.h
+++ b/src/endgame.h
@@ -1,7 +1,7 @@
 /*
   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
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -17,89 +17,108 @@
   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 <memory>
+#include <string>
+#include <type_traits>
+#include <utility>
 
 #include "position.h"
-#include "scale.h"
-#include "value.h"
+#include "types.h"
 
 
-////
-//// Types
-////
+/// EndgameType lists all supported endgames
 
 enum EndgameType {
 
-    // Evaluation functions
-    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
-    KQKR,  // KQ vs KR
-    KBBKN, // KBB vs KN
-    KmmKm, // K and two minors vs K and one or two minors
-
-    // Scaling functions
-    KBPK,    // KBP vs K
-    KQKRP,   // KQ vs KRP
-    KRPKR,   // KRP vs KR
-    KRPPKRP, // KRPP vs KRP
-    KPsK,    // King and pawns vs king
-    KBPKB,   // KBP vs KB
-    KBPPKB,  // KBPP vs KB
-    KBPKN,   // KBP vs KN
-    KNPK,    // KNP vs K
-    KPKP     // KP vs KP
+  // Evaluation functions
+
+  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
+
+
+  // Scaling functions
+  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,    // 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
 };
 
-/// Template abstract base class for all special endgame functions
+
+/// Endgame functions can be of two types depending on whether they return a
+/// Value or a ScaleFactor.
+template<EndgameType E> using
+eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
+
+
+/// Base and derived templates for endgame evaluation and scaling functions
 
 template<typename T>
-class EndgameFunctionBase {
-public:
-  EndgameFunctionBase(Color c) : strongerSide(c), weakerSide(opposite_color(c)) {}
-  virtual ~EndgameFunctionBase() {}
-  virtual T apply(const Position&) = 0;
-  Color color() const { return strongerSide; }
+struct EndgameBase {
 
-protected:
-  Color strongerSide, weakerSide;
+  virtual ~EndgameBase() {}
+  virtual Color strong_side() const = 0;
+  virtual T operator()(const Position&) const = 0;
 };
 
-typedef EndgameFunctionBase<Value> EndgameEvaluationFunctionBase;
-typedef EndgameFunctionBase<ScaleFactor> EndgameScalingFunctionBase;
 
+template<EndgameType E, typename T = eg_type<E>>
+struct Endgame : public EndgameBase<T> {
 
-/// Templates subclass for various concrete endgames
+  explicit Endgame(Color c) : strongSide(c), weakSide(~c) {}
+  Color strong_side() const { return strongSide; }
+  T operator()(const Position&) const;
 
-template<EndgameType>
-struct EvaluationFunction : public EndgameEvaluationFunctionBase {
-  typedef EndgameEvaluationFunctionBase Base;
-  explicit EvaluationFunction(Color c): EndgameEvaluationFunctionBase(c) {}
-  Value apply(const Position&);
+private:
+  Color strongSide, weakSide;
 };
 
-template<EndgameType>
-struct ScalingFunction : public EndgameScalingFunctionBase {
-  typedef EndgameScalingFunctionBase Base;
-  explicit ScalingFunction(Color c) : EndgameScalingFunctionBase(c) {}
-  ScaleFactor apply(const Position&);
-};
 
+/// 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().
 
-////
-//// Prototypes
-////
+class Endgames {
 
-extern void init_bitbases();
+  template<typename T> using Map = std::map<Key, std::unique_ptr<EndgameBase<T>>>;
 
+  template<EndgameType E, typename T = eg_type<E>>
+  void add(const std::string& code);
+
+  template<typename T>
+  Map<T>& map() {
+    return std::get<std::is_same<T, ScaleFactor>::value>(maps);
+  }
+
+  std::pair<Map<Value>, Map<ScaleFactor>> maps;
+
+public:
+  Endgames();
+
+  template<typename T>
+  EndgameBase<T>* probe(Key key) {
+    return map<T>().count(key) ? map<T>()[key].get() : nullptr;
+  }
+};
 
-#endif // !defined(ENDGAME_H_INCLUDED)
+#endif // #ifndef ENDGAME_H_INCLUDED