X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.h;h=e29f877782cd6c67501d751394cbc3f599c5dd7b;hp=21e8ab6d6e5b6d249a765f0c4381c9cf7465f93a;hb=7756344d5d2b93970e7cd423f8cbf6fb1da11b74;hpb=039badfda8fa05bc466612bce996837c7d69f22b

diff --git a/src/endgame.h b/src/endgame.h
index 21e8ab6d..e29f8777 100644
--- a/src/endgame.h
+++ b/src/endgame.h
@@ -1,7 +1,8 @@
 /*
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
-  Copyright (C) 2008 Marco Costalba
+  Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2015-2019 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
@@ -17,185 +18,110 @@
   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 <unordered_map>
+#include <memory>
+#include <string>
+#include <type_traits>
+#include <utility>
 
 #include "position.h"
-#include "scale.h"
-#include "value.h"
-
-
-////
-//// Types
-////
-
-/// Abstract base class for all special endgame evaluation functions
-
-class EndgameEvaluationFunction {
-public:
-  EndgameEvaluationFunction(Color c);
-  virtual ~EndgameEvaluationFunction() { }
-
-  virtual Value apply(const Position &pos) = 0;
-
-protected:
-  Color strongerSide, weakerSide;
-};
-
-
-/// Template subclass for various concrete endgames
-
-enum EndgameType {
-    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
+#include "types.h"
+
+
+/// EndgameCode lists all supported endgame functions by corresponding codes
+
+enum EndgameCode {
+
+  EVALUATION_FUNCTIONS,
+  KNNK,  // KNN vs K
+  KNNKP, // KNN vs KP
+  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,
+  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<EndgameType>
-class EvaluationFunction : public EndgameEvaluationFunction {
-public:
-  explicit EvaluationFunction(Color c): EndgameEvaluationFunction(c) {}
-  Value apply(const Position& pos);
-};
 
-/// Abstract base class for all evaluation scaling functions:
+/// Endgame functions can be of two types depending on whether they return a
+/// Value or a ScaleFactor.
 
-class ScalingFunction {
-public:
-  ScalingFunction(Color c);
-  virtual ~ScalingFunction() { }
+template<EndgameCode E> using
+eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
 
-  virtual ScaleFactor apply(const Position &pos) =0;
 
-protected:
-  Color strongerSide, weakerSide;
-};
+/// Base and derived functors for endgame evaluation and scaling functions
 
+template<typename T>
+struct EndgameBase {
 
-/// Subclasses for various concrete endgames:
+  explicit EndgameBase(Color c) : strongSide(c), weakSide(~c) {}
+  virtual ~EndgameBase() = default;
+  virtual T operator()(const Position&) const = 0;
 
-// KBP vs K:
-class KBPKScalingFunction : public ScalingFunction {
-public:
-  KBPKScalingFunction(Color c);
-  ScaleFactor apply(const Position &pos);
+  const Color strongSide, weakSide;
 };
 
-// KQ vs KRP:
-class KQKRPScalingFunction: public ScalingFunction {
-public:
-  KQKRPScalingFunction(Color c);
-  ScaleFactor apply(const Position &pos);
-};
 
-// KRP vs KR:
-class KRPKRScalingFunction : public ScalingFunction {
-public:
-  KRPKRScalingFunction(Color c);
-  ScaleFactor apply(const Position &pos);
-};
+template<EndgameCode E, typename T = eg_type<E>>
+struct Endgame : public EndgameBase<T> {
 
-// KRPP vs KRP:
-class KRPPKRPScalingFunction : public ScalingFunction {
-public:
-  KRPPKRPScalingFunction(Color c);
-  ScaleFactor apply(const Position &pos);
+  explicit Endgame(Color c) : EndgameBase<T>(c) {}
+  T operator()(const Position&) const override;
 };
 
-// King and pawns vs king:
-class KPsKScalingFunction : public ScalingFunction {
-public:
-  KPsKScalingFunction(Color c);
-  ScaleFactor apply(const Position &pos);
-};
-
-// 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);
-};
-
-// 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);
-};
-
-
-////
-//// Constants and variables
-////
-
-extern EvaluationFunction<KXK> EvaluateKXK, EvaluateKKX;       // Generic "mate lone king" eval
-extern EvaluationFunction<KBNK> EvaluateKBNK, EvaluateKKBN;    // KBN vs K
-extern EvaluationFunction<KPK> EvaluateKPK, EvaluateKKP;       // KP vs K
-extern EvaluationFunction<KRKP> EvaluateKRKP, EvaluateKPKR;    // KR vs KP
-extern EvaluationFunction<KRKB> EvaluateKRKB, EvaluateKBKR;    // KR vs KB
-extern EvaluationFunction<KRKN> EvaluateKRKN, EvaluateKNKR;    // KR vs KN
-extern EvaluationFunction<KQKR> EvaluateKQKR, EvaluateKRKQ;    // KQ vs KR
-extern EvaluationFunction<KBBKN> EvaluateKBBKN, EvaluateKNKBB; // KBB vs KN
-extern EvaluationFunction<KmmKm> EvaluateKmmKm; // K and two minors vs K and one or two minors:
-
-// 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;
+/// The Endgames namespace handles 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 KB:
-extern KBPKBScalingFunction ScaleKBPKB, ScaleKBKBP;
+namespace Endgames {
 
-// KBP vs KN:
-extern KBPKNScalingFunction ScaleKBPKN, ScaleKNKBP;
+  template<typename T> using Ptr = std::unique_ptr<EndgameBase<T>>;
+  template<typename T> using Map = std::unordered_map<Key, Ptr<T>>;
 
-// KNP vs K:
-extern KNPKScalingFunction ScaleKNPK, ScaleKKNP;
+  extern std::pair<Map<Value>, Map<ScaleFactor>> maps;
 
-// KP vs KP:
-extern KPKPScalingFunction ScaleKPKPw, ScaleKPKPb;
+  void init();
 
+  template<typename T>
+  Map<T>& map() {
+    return std::get<std::is_same<T, ScaleFactor>::value>(maps);
+  }
 
-////
-//// Prototypes
-////
+  template<EndgameCode E, typename T = eg_type<E>>
+  void add(const std::string& code) {
 
-extern void init_bitbases();
+    StateInfo st;
+    map<T>()[Position().set(code, WHITE, &st).material_key()] = Ptr<T>(new Endgame<E>(WHITE));
+    map<T>()[Position().set(code, BLACK, &st).material_key()] = Ptr<T>(new Endgame<E>(BLACK));
+  }
 
+  template<typename T>
+  const EndgameBase<T>* probe(Key key) {
+    auto it = map<T>().find(key);
+    return it != map<T>().end() ? it->second.get() : nullptr;
+  }
+}
 
-#endif // !defined(ENDGAME_H_INCLUDED)
+#endif // #ifndef ENDGAME_H_INCLUDED