Rename castling flag to castling right

[stockfish] / src / pawns.cpp

diff --git a/src/pawns.cpp b/src/pawns.cpp
index 74ae4c2ff5ee78d47036d32aae73d260d0d51468..88c63ce3a3d4ad518720d887cdb7fab974f92b16 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -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) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
+  Copyright (C) 2008-2014 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
@@ -240,6 +240,7 @@ template<Color Us>
 Value Entry::shelter_storm(const Position& pos, Square ksq) {
 
   const Color Them = (Us == WHITE ? BLACK : WHITE);
+  static const Bitboard MiddleEdges = (FileABB | FileHBB) & (Rank2BB | Rank3BB);
 
   Value safety = MaxSafetyBonus;
   Bitboard b = pos.pieces(PAWN) & (in_front_bb(Us, rank_of(ksq)) | rank_bb(ksq));
@@ -252,11 +253,17 @@ Value Entry::shelter_storm(const Position& pos, Square ksq) {
   {
       b = ourPawns & file_bb(f);
       rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1;
-      safety -= ShelterWeakness[rkUs];
 
       b  = theirPawns & file_bb(f);
       rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
-      safety -= StormDanger[rkUs == RANK_1 ? 0 : rkThem == rkUs + 1 ? 2 : 1][rkThem];
+
+      if (   (MiddleEdges & (f | rkThem))
+          && file_of(ksq) == f
+          && relative_rank(Us, ksq) == rkThem - 1)
+          safety += Value(200);
+      else
+          safety -= ShelterWeakness[rkUs]
+                  + StormDanger[rkUs == RANK_1 ? 0 : rkThem == rkUs + 1 ? 2 : 1][rkThem];
   }
 
   return safety;
@@ -271,7 +278,7 @@ template<Color Us>
 Score Entry::update_safety(const Position& pos, Square ksq) {
 
   kingSquares[Us] = ksq;
-  castlingFlags[Us] = pos.can_castle(Us);
+  castlingRights[Us] = pos.can_castle(Us);
   minKPdistance[Us] = 0;
 
   Bitboard pawns = pos.pieces(Us, PAWN);
@@ -284,10 +291,10 @@ Score Entry::update_safety(const Position& pos, Square ksq) {
   Value bonus = shelter_storm<Us>(pos, ksq);
 
   // If we can castle use the bonus after the castling if it is bigger
-  if (pos.can_castle(make_castling_flag(Us, KING_SIDE)))
+  if (pos.can_castle(MakeCastling<Us, KING_SIDE>::right))
       bonus = std::max(bonus, shelter_storm<Us>(pos, relative_square(Us, SQ_G1)));
 
-  if (pos.can_castle(make_castling_flag(Us, QUEEN_SIDE)))
+  if (pos.can_castle(MakeCastling<Us, QUEEN_SIDE>::right))
       bonus = std::max(bonus, shelter_storm<Us>(pos, relative_square(Us, SQ_C1)));
 
   return kingSafety[Us] = make_score(bonus, -16 * minKPdistance[Us]);