Use self-describing constants instead of numbers

[stockfish] / src / material.h

diff --git a/src/material.h b/src/material.h
index 9992c0b71c51ba55dafde449f61c75f6b4b2b929..89f8f55685d0979b1cf6f07d748e897ee9df6c08 100644 (file)
--- a/src/material.h
+++ b/src/material.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) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2012 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
@@ -21,12 +21,13 @@
 #define MATERIAL_H_INCLUDED
 
 #include "endgame.h"
+#include "misc.h"
 #include "position.h"
-#include "tt.h"
+#include "types.h"
 
-const int MaterialTableSize = 1024;
+const int MaterialTableSize = 8192;
 
-/// MaterialInfo is a class which contains various information about a
+/// MaterialEntry is a class which contains various information about a
 /// material configuration. It contains a material balance evaluation,
 /// a function pointer to a special endgame evaluation function (which in
 /// most cases is NULL, meaning that the standard evaluation function will
@@ -36,9 +37,9 @@ const int MaterialTableSize = 1024;
 /// For instance, in KRB vs KR endgames, the score is scaled down by a factor
 /// of 4, which will result in scores of absolute value less than one pawn.
 
-class MaterialInfo {
+class MaterialEntry {
 
-  friend class MaterialInfoTable;
+  friend struct MaterialTable;
 
 public:
   Score material_value() const;
@@ -51,91 +52,62 @@ public:
 private:
   Key key;
   int16_t value;
-  uint8_t factor[2];
-  EndgameEvaluationFunctionBase* evaluationFunction;
-  EndgameScalingFunctionBase* scalingFunction[2];
+  uint8_t factor[COLOR_NB];
+  EndgameBase<Value>* evaluationFunction;
+  EndgameBase<ScaleFactor>* scalingFunction[COLOR_NB];
   int spaceWeight;
   Phase gamePhase;
 };
 
-/// The MaterialInfoTable class represents a pawn hash table. The most important
-/// method is get_material_info, which returns a pointer to a MaterialInfo object.
-class EndgameFunctions;
 
-class MaterialInfoTable : public SimpleHash<MaterialInfo, MaterialTableSize> {
-public:
-  MaterialInfoTable();
-  ~MaterialInfoTable();
-  MaterialInfo* get_material_info(const Position& pos);
-  static Phase game_phase(const Position& pos);
-private:
-  EndgameFunctions* funcs;
-};
+/// The MaterialTable class represents a material hash table. The most important
+/// method is probe(), which returns a pointer to a MaterialEntry object.
 
+struct MaterialTable {
 
-/// MaterialInfo::material_value simply returns the material balance
-/// evaluation that is independent from game phase.
-
-inline Score MaterialInfo::material_value() const {
+  MaterialEntry* probe(const Position& pos);
+  static Phase game_phase(const Position& pos);
+  template<Color Us> static int imbalance(const int pieceCount[][PIECE_TYPE_NB]);
 
-  return make_score(value, value);
-}
+  HashTable<MaterialEntry, MaterialTableSize> entries;
+  Endgames endgames;
+};
 
 
-/// MaterialInfo::scale_factor takes a position and a color as input, and
+/// MaterialEntry::scale_factor takes a position and a color as input, and
 /// returns a scale factor for the given color. We have to provide the
 /// position in addition to the color, because the scale factor need not
 /// to be a constant: It can also be a function which should be applied to
 /// the position. For instance, in KBP vs K endgames, a scaling function
 /// which checks for draws with rook pawns and wrong-colored bishops.
 
-inline ScaleFactor MaterialInfo::scale_factor(const Position& pos, Color c) const {
+inline ScaleFactor MaterialEntry::scale_factor(const Position& pos, Color c) const {
 
-  if (scalingFunction[c] != NULL)
-  {
-      ScaleFactor sf = scalingFunction[c]->apply(pos);
-      if (sf != SCALE_FACTOR_NONE)
-          return sf;
-  }
-  return ScaleFactor(factor[c]);
-}
+  if (!scalingFunction[c])
+      return ScaleFactor(factor[c]);
 
+  ScaleFactor sf = (*scalingFunction[c])(pos);
+  return sf == SCALE_FACTOR_NONE ? ScaleFactor(factor[c]) : sf;
+}
 
-/// MaterialInfo::space_weight() simply returns the weight for the space
-/// evaluation for this material configuration.
+inline Value MaterialEntry::evaluate(const Position& pos) const {
+  return (*evaluationFunction)(pos);
+}
 
-inline int MaterialInfo::space_weight() const {
+inline Score MaterialEntry::material_value() const {
+  return make_score(value, value);
+}
 
+inline int MaterialEntry::space_weight() const {
   return spaceWeight;
 }
 
-
-/// MaterialInfo::game_phase() returns the game phase according
-/// to this material configuration.
-
-inline Phase MaterialInfo::game_phase() const {
-
+inline Phase MaterialEntry::game_phase() const {
   return gamePhase;
 }
 
-
-/// MaterialInfo::specialized_eval_exists decides whether there is a
-/// specialized evaluation function for the current material configuration,
-/// or if the normal evaluation function should be used.
-
-inline bool MaterialInfo::specialized_eval_exists() const {
-
+inline bool MaterialEntry::specialized_eval_exists() const {
   return evaluationFunction != NULL;
 }
 
-
-/// MaterialInfo::evaluate applies a specialized evaluation function
-/// to a given position object. It should only be called when
-/// specialized_eval_exists() returns 'true'.
-
-inline Value MaterialInfo::evaluate(const Position& pos) const {
-
-  return evaluationFunction->apply(pos);
-}
-
 #endif // !defined(MATERIAL_H_INCLUDED)