]> git.sesse.net Git - stockfish/blobdiff - src/material.cpp
Another small material tweak
[stockfish] / src / material.cpp
index 732aded7b3285b9bdd931669fc8d4a569ce5f240..fc2f4b7cf35e454687c4ec2ead6a7276ea0546bd 100644 (file)
@@ -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) 2008-2010 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
@@ -55,17 +55,40 @@ namespace {
   { 41, 41, 41, 41, 41, 41 }, { 37, 41, 41, 41, 41, 41 }, { 10, 62, 41, 41, 41, 41 },
   { 57, 64, 39, 41, 41, 41 }, { 50, 40, 23, -22, 41, 41 }, { 106, 101, 3, 151, 171, 41 } };
 
-  // Named endgame evaluation and scaling functions, these
-  // are accessed direcly and not through the function maps.
-  EvaluationFunction<KmmKm> EvaluateKmmKm(WHITE);
-  EvaluationFunction<KXK>   EvaluateKXK(WHITE), EvaluateKKX(BLACK);
-  ScalingFunction<KBPsK>    ScaleKBPsK(WHITE),  ScaleKKBPs(BLACK);
-  ScalingFunction<KQKRPs>   ScaleKQKRPs(WHITE), ScaleKRPsKQ(BLACK);
-  ScalingFunction<KPsK>     ScaleKPsK(WHITE),   ScaleKKPs(BLACK);
-  ScalingFunction<KPKP>     ScaleKPKPw(WHITE),  ScaleKPKPb(BLACK);
-
   typedef EndgameEvaluationFunctionBase EF;
   typedef EndgameScalingFunctionBase SF;
+
+  // Endgame evaluation and scaling functions accessed direcly and not through
+  // the function maps because correspond to more then one material hash key.
+  EvaluationFunction<KmmKm> EvaluateKmmKm[] = { EvaluationFunction<KmmKm>(WHITE), EvaluationFunction<KmmKm>(BLACK) };
+  EvaluationFunction<KXK>   EvaluateKXK[]   = { EvaluationFunction<KXK>(WHITE),   EvaluationFunction<KXK>(BLACK) };
+  ScalingFunction<KBPsK>    ScaleKBPsK[]    = { ScalingFunction<KBPsK>(WHITE),    ScalingFunction<KBPsK>(BLACK) };
+  ScalingFunction<KQKRPs>   ScaleKQKRPs[]   = { ScalingFunction<KQKRPs>(WHITE),   ScalingFunction<KQKRPs>(BLACK) };
+  ScalingFunction<KPsK>     ScaleKPsK[]     = { ScalingFunction<KPsK>(WHITE),     ScalingFunction<KPsK>(BLACK) };
+  ScalingFunction<KPKP>     ScaleKPKP[]     = { ScalingFunction<KPKP>(WHITE),     ScalingFunction<KPKP>(BLACK) };
+
+  // Helper templates used to detect a given material distribution
+  template<Color Us> bool is_KXK(const Position& pos) {
+    const Color Them = (Us == WHITE ? BLACK : WHITE);
+    return   pos.non_pawn_material(Them) == Value(0)
+          && pos.piece_count(Them, PAWN) == 0
+          && pos.non_pawn_material(Us) >= RookValueMidgame;
+  }
+
+  template<Color Us> bool is_KBPsK(const Position& pos) {
+    return   pos.non_pawn_material(Us)   == BishopValueMidgame
+          && pos.piece_count(Us, BISHOP) == 1
+          && pos.piece_count(Us, PAWN)   >= 1;
+  }
+
+  template<Color Us> bool is_KQKRPs(const Position& pos) {
+    const Color Them = (Us == WHITE ? BLACK : WHITE);
+    return   pos.piece_count(Us, PAWN)    == 0
+          && pos.non_pawn_material(Us)    == QueenValueMidgame
+          && pos.piece_count(Us, QUEEN)   == 1
+          && pos.piece_count(Them, ROOK)  == 1
+          && pos.piece_count(Them, PAWN)  >= 1;
+  }
 }
 
 
@@ -181,22 +204,13 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
   if ((mi->evaluationFunction = funcs->get<EF>(key)) != NULL)
       return mi;
 
-  else if (   pos.non_pawn_material(BLACK) == Value(0)
-           && pos.piece_count(BLACK, PAWN) == 0
-           && pos.non_pawn_material(WHITE) >= RookValueMidgame)
+  else if (is_KXK<WHITE>(pos) || is_KXK<BLACK>(pos))
   {
-      mi->evaluationFunction = &EvaluateKXK;
+      mi->evaluationFunction = is_KXK<WHITE>(pos) ? &EvaluateKXK[WHITE] : &EvaluateKXK[BLACK];
       return mi;
   }
-  else if (   pos.non_pawn_material(WHITE) == Value(0)
-           && pos.piece_count(WHITE, PAWN) == 0
-           && pos.non_pawn_material(BLACK) >= RookValueMidgame)
-  {
-      mi->evaluationFunction = &EvaluateKKX;
-      return mi;
-  }
-  else if (   pos.pieces(PAWN) == EmptyBoardBB
-           && pos.pieces(ROOK) == EmptyBoardBB
+  else if (   pos.pieces(PAWN)  == EmptyBoardBB
+           && pos.pieces(ROOK)  == EmptyBoardBB
            && pos.pieces(QUEEN) == EmptyBoardBB)
   {
       // Minor piece endgame with at least one minor piece per side and
@@ -207,7 +221,7 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
       if (   pos.piece_count(WHITE, BISHOP) + pos.piece_count(WHITE, KNIGHT) <= 2
           && pos.piece_count(BLACK, BISHOP) + pos.piece_count(BLACK, KNIGHT) <= 2)
       {
-          mi->evaluationFunction = &EvaluateKmmKm;
+          mi->evaluationFunction = &EvaluateKmmKm[WHITE];
           return mi;
       }
   }
@@ -230,48 +244,36 @@ MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) {
   // Generic scaling functions that refer to more then one material
   // distribution. Should be probed after the specialized ones.
   // Note that these ones don't return after setting the function.
-  if (   pos.non_pawn_material(WHITE) == BishopValueMidgame
-      && pos.piece_count(WHITE, BISHOP) == 1
-      && pos.piece_count(WHITE, PAWN) >= 1)
-      mi->scalingFunction[WHITE] = &ScaleKBPsK;
-
-  if (   pos.non_pawn_material(BLACK) == BishopValueMidgame
-      && pos.piece_count(BLACK, BISHOP) == 1
-      && pos.piece_count(BLACK, PAWN) >= 1)
-      mi->scalingFunction[BLACK] = &ScaleKKBPs;
-
-  if (   pos.piece_count(WHITE, PAWN) == 0
-      && pos.non_pawn_material(WHITE) == QueenValueMidgame
-      && pos.piece_count(WHITE, QUEEN) == 1
-      && pos.piece_count(BLACK, ROOK) == 1
-      && pos.piece_count(BLACK, PAWN) >= 1)
-      mi->scalingFunction[WHITE] = &ScaleKQKRPs;
-
-  else if (   pos.piece_count(BLACK, PAWN) == 0
-           && pos.non_pawn_material(BLACK) == QueenValueMidgame
-           && pos.piece_count(BLACK, QUEEN) == 1
-           && pos.piece_count(WHITE, ROOK) == 1
-           && pos.piece_count(WHITE, PAWN) >= 1)
-      mi->scalingFunction[BLACK] = &ScaleKRPsKQ;
+  if (is_KBPsK<WHITE>(pos))
+      mi->scalingFunction[WHITE] = &ScaleKBPsK[WHITE];
+
+  if (is_KBPsK<BLACK>(pos))
+      mi->scalingFunction[BLACK] = &ScaleKBPsK[BLACK];
+
+  if (is_KQKRPs<WHITE>(pos))
+      mi->scalingFunction[WHITE] = &ScaleKQKRPs[WHITE];
+
+  else if (is_KQKRPs<BLACK>(pos))
+      mi->scalingFunction[BLACK] = &ScaleKQKRPs[BLACK];
 
   if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) == Value(0))
   {
       if (pos.piece_count(BLACK, PAWN) == 0)
       {
           assert(pos.piece_count(WHITE, PAWN) >= 2);
-          mi->scalingFunction[WHITE] = &ScaleKPsK;
+          mi->scalingFunction[WHITE] = &ScaleKPsK[WHITE];
       }
       else if (pos.piece_count(WHITE, PAWN) == 0)
       {
           assert(pos.piece_count(BLACK, PAWN) >= 2);
-          mi->scalingFunction[BLACK] = &ScaleKKPs;
+          mi->scalingFunction[BLACK] = &ScaleKPsK[BLACK];
       }
       else if (pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1)
       {
           // This is a special case because we set scaling functions
           // for both colors instead of only one.
-          mi->scalingFunction[WHITE] = &ScaleKPKPw;
-          mi->scalingFunction[BLACK] = &ScaleKPKPb;
+          mi->scalingFunction[WHITE] = &ScaleKPKP[WHITE];
+          mi->scalingFunction[BLACK] = &ScaleKPKP[BLACK];
       }
   }