X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.h;h=941cb31017a6ef0c3d373c9ba17abfea9036dc5d;hp=ceb93efad91b057a4e2ab60d483a4cd3a6e3a4a2;hb=58d3ee61757215292b48e32caec9931d901c2940;hpb=0fcda095df1caa860e8e3f3a714d5545ec9dc122

diff --git a/src/endgame.h b/src/endgame.h
index ceb93efa..941cb310 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) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+  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
@@ -17,71 +18,128 @@
   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
 
+#include <map>
+#include <memory>
+#include <string>
+#include <type_traits>
+#include <utility>
+
 #include "position.h"
 #include "types.h"
 
-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
-    KNNK,  // KNN vs K
-    KmmKm, // K and two minors vs K and one or two minors
-
-    // Scaling functions
-    KBPsK,   // KB+pawns vs K
-    KQKRPs,  // KQ vs KR+pawns
-    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
+
+/// EndgameCode lists all supported endgame functions by corresponding codes
+
+enum EndgameCode {
+
+  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,
+  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<EndgameCode E> using
+eg_type = typename std::conditional<(E < SCALING_FUNCTIONS), Value, ScaleFactor>::type;
+
+
+/// Base and derived functors 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&) const = 0;
-  Color color() const { return strongerSide; }
+struct EndgameBase {
 
-protected:
-  Color strongerSide, weakerSide;
-};
+  explicit EndgameBase(Color c) : strongSide(c), weakSide(~c) {}
+  virtual ~EndgameBase() = default;
+  virtual T operator()(const Position&) const = 0;
 
-typedef EndgameFunctionBase<Value> EndgameEvaluationFunctionBase;
-typedef EndgameFunctionBase<ScaleFactor> EndgameScalingFunctionBase;
+  const Color strongSide, weakSide;
+};
 
 
-/// Templates subclass for various concrete endgames
+template<EndgameCode E, typename T = eg_type<E>>
+struct Endgame : public EndgameBase<T> {
 
-template<EndgameType>
-struct EvaluationFunction : public EndgameEvaluationFunctionBase {
-  typedef EndgameEvaluationFunctionBase Base;
-  explicit EvaluationFunction(Color c): EndgameEvaluationFunctionBase(c) {}
-  Value apply(const Position&) const;
+  explicit Endgame(Color c) : EndgameBase<T>(c) {}
+  T operator()(const Position&) const override;
 };
 
-template<EndgameType>
-struct ScalingFunction : public EndgameScalingFunctionBase {
-  typedef EndgameScalingFunctionBase Base;
-  explicit ScalingFunction(Color c) : EndgameScalingFunctionBase(c) {}
-  ScaleFactor apply(const Position&) const;
+
+/// 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 {
+
+  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);
+  }
+
+  template<EndgameCode E, typename T = eg_type<E>>
+  void add(const std::string& code) {
+
+    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));
+  }
+
+  std::pair<Map<Value>, Map<ScaleFactor>> maps;
+
+public:
+  Endgames() {
+
+    add<KPK>("KPK");
+    add<KNNK>("KNNK");
+    add<KBNK>("KBNK");
+    add<KRKP>("KRKP");
+    add<KRKB>("KRKB");
+    add<KRKN>("KRKN");
+    add<KQKP>("KQKP");
+    add<KQKR>("KQKR");
+
+    add<KNPK>("KNPK");
+    add<KNPKB>("KNPKB");
+    add<KRPKR>("KRPKR");
+    add<KRPKB>("KRPKB");
+    add<KBPKB>("KBPKB");
+    add<KBPKN>("KBPKN");
+    add<KBPPKB>("KBPPKB");
+    add<KRPPKRP>("KRPPKRP");
+  }
+
+  template<typename T>
+  const 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