X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=981bad3e846f31cb8459efd82f5884ba5d17aa62;hp=0099ccd2f8e08f1a6e1b3fb2539da5cdff5b4803;hb=0bf45823da3d76d25d0e3cfdf131bf8823ecb58e;hpb=257689dec7a1d64658cb80d285a78e8d49141619

diff --git a/src/position.h b/src/position.h
index 0099ccd2..981bad3e 100644
--- a/src/position.h
+++ b/src/position.h
@@ -1,17 +1,18 @@
 /*
-  Glaurung, a UCI chess playing engine.
-  Copyright (C) 2004-2008 Tord Romstad
+  Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+  Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+  Copyright (C) 2008 Marco Costalba
 
-  Glaurung is free software: you can redistribute it and/or modify
+  Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.
-  
-  Glaurung is distributed in the hope that it will be useful,
+
+  Stockfish is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
-  
+
   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
@@ -24,8 +25,8 @@
 #if defined(_MSC_VER)
 
 // Forcing value to bool 'true' or 'false' (performance warning)
-#pragma warning(disable: 4800) 
-
+#pragma warning(disable: 4800)
+
 #endif
 
 ////
@@ -47,7 +48,7 @@
 ////
 
 /// FEN string for the initial position:
-const std::string StartPosition = 
+const std::string StartPosition =
   "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1";
 
 /// Maximum number of plies per game (220 should be enough, because the
@@ -63,35 +64,34 @@ const int MaxGameLength = 220;
 /// Castle rights, encoded as bit fields:
 
 enum CastleRights {
-  NO_CASTLES = 0, 
+  NO_CASTLES = 0,
   WHITE_OO = 1,
-  BLACK_OO = 2, 
+  BLACK_OO = 2,
   WHITE_OOO = 4,
   BLACK_OOO = 8,
   ALL_CASTLES = 15
 };
 
 
-/// The UndoInfo struct stores information we need to restore a Position
-/// object to its previous state when we retract a move.  Whenever a move
-/// is made on the board (by calling Position::do_move), an UndoInfo object
-/// must be passed as a parameter.  When the move is unmade (by calling
-/// Position::undo_move), the same UndoInfo object must be passed again.
+/// The StateInfo struct stores information we need to restore a Position
+/// object to its previous state when we retract a move. Whenever a move
+/// is made on the board (by calling Position::do_move), an StateInfo object
+/// must be passed as a parameter.
 
-struct UndoInfo {
-  int castleRights;
-  Square epSquare;
-  Bitboard checkersBB;
+struct StateInfo {
+  Bitboard pinners[2], pinned[2], dcCandidates[2], checkersBB;
   Key key, pawnKey, materialKey;
-  int rule50;
+  int castleRights, rule50;
+  Square epSquare;
   Move lastMove;
-  PieceType capture;
   Value mgValue, egValue;
+  PieceType capture;
+  StateInfo* previous;
 };
 
 
 /// The position data structure.  A position consists of the following data:
-///    
+///
 ///    * For each piece type, a bitboard representing the squares occupied
 ///      by pieces of that type.
 ///    * For each color, a bitboard representing the squares occupiecd by
@@ -116,17 +116,18 @@ struct UndoInfo {
 class Position {
 
   friend class MaterialInfo;
+  friend class EndgameFunctions;
 
 public:
   // Constructors
   Position() {};
-  Position(const Position &pos);
-  Position(const std::string &fen);
+  Position(const Position& pos);
+  Position(const std::string& fen);
 
   // Text input/output
-  void from_fen(const std::string &fen);
+  void from_fen(const std::string& fen);
   const std::string to_fen() const;
-  void print() const;
+  void print(Move m = MOVE_NONE) const;
 
   // Copying
   void copy(const Position &pos);
@@ -171,19 +172,14 @@ public:
 
   // Number of pieces of each color and type
   int piece_count(Color c, PieceType pt) const;
-  int pawn_count(Color c) const;
-  int knight_count(Color c) const;
-  int bishop_count(Color c) const;
-  int rook_count(Color c) const;
-  int queen_count(Color c) const;
 
-  // The en passant square:
+  // The en passant square
   Square ep_square() const;
 
   // Current king position for each color
   Square king_square(Color c) const;
 
-  // Castling rights.
+  // Castling rights
   bool can_castle_kingside(Color c) const;
   bool can_castle_queenside(Color c) const;
   bool can_castle(Color c) const;
@@ -200,6 +196,7 @@ public:
 
   // Bitboards for pinned pieces and discovered check candidates
   Bitboard discovered_check_candidates(Color c) const;
+  Bitboard pinned_pieces(Color c, Bitboard& p) const;
   Bitboard pinned_pieces(Color c) const;
 
   // Checking pieces
@@ -218,13 +215,11 @@ public:
   template<PieceType>
   Bitboard piece_attacks_square(Square f, Square t) const; // Dispatch at compile-time
 
-  bool piece_attacks_square(Square f, Square t) const; // Dispatch at run-time
+  bool piece_attacks_square(Piece p, Square f, Square t) const; // Dispatch at run-time
 
   // Properties of moves
-  bool move_is_legal(Move m) const;
-  bool move_is_legal(Move m, Bitboard pinned) const;
+  bool pl_move_is_legal(Move m) const;
   bool move_is_check(Move m) const;
-  bool move_is_check(Move m, Bitboard dcCandidates) const;
   bool move_is_capture(Move m) const;
   bool move_is_deep_pawn_push(Move m) const;
   bool move_is_pawn_push_to_7th(Move m) const;
@@ -245,17 +240,15 @@ public:
   bool square_is_weak(Square s, Color c) const;
 
   // Doing and undoing moves
-  void backup(UndoInfo &u) const;
-  void restore(const UndoInfo &u);
-  void do_move(Move m, UndoInfo &u);
-  void do_move(Move m, UndoInfo &u, Bitboard dcCandidates);
-  void undo_move(Move m, const UndoInfo &u);
-  void do_null_move(UndoInfo &u);
-  void undo_null_move(const UndoInfo &u);
+  void do_move(Move m, StateInfo& st);
+  void undo_move(Move m);
+  void do_null_move(StateInfo& st);
+  void undo_null_move();
 
   // Static exchange evaluation
   int see(Square from, Square to) const;
   int see(Move m) const;
+  int see(Square to) const;
 
   // Accessing hash keys
   Key get_key() const;
@@ -270,7 +263,7 @@ public:
   Value mg_pst_delta(Move m) const;
 
   // Game termination checks
-  bool is_mate();
+  bool is_mate() const;
   bool is_draw() const;
 
   // Check if one side threatens a mate in one
@@ -285,7 +278,7 @@ public:
 
   // Reset the gamePly variable to 0
   void reset_game_ply();
-  
+
   // Position consistency check, for debugging
   bool is_ok(int* failedStep = NULL) const;
 
@@ -301,13 +294,21 @@ private:
   void allow_ooo(Color c);
 
   // Helper functions for doing and undoing moves
+  void do_capture_move(Move m, PieceType capture, Color them, Square to);
   void do_castle_move(Move m);
-  void do_promotion_move(Move m, UndoInfo &u);
+  void do_promotion_move(Move m);
   void do_ep_move(Move m);
   void undo_castle_move(Move m);
-  void undo_promotion_move(Move m, const UndoInfo &u);
+  void undo_promotion_move(Move m);
   void undo_ep_move(Move m);
   void find_checkers();
+  void find_pinned();
+
+  template<PieceType Piece>
+  void update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, Square to, Bitboard dcCandidates);
+
+  template<PieceType Piece, bool FindPinned>
+  Bitboard hidden_checks(Color c, Square ksq, Bitboard& pinners) const;
 
   // Computing hash keys from scratch (for initialization and debugging)
   Key compute_key() const;
@@ -315,37 +316,36 @@ private:
   Key compute_material_key() const;
 
   // Computing incremental evaluation scores and material counts
-  Value mg_pst(Color c, PieceType pt, Square s) const;
-  Value eg_pst(Color c, PieceType pt, Square s) const;
-  Value compute_mg_value() const;
-  Value compute_eg_value() const;
+  enum GamePhase {
+      MidGame,
+      EndGame
+  };
+  template<GamePhase> Value pst(Color c, PieceType pt, Square s) const;
+  template<GamePhase> Value compute_value() const;
   Value compute_non_pawn_material(Color c) const;
 
   // Bitboards
   Bitboard byColorBB[2], byTypeBB[8];
-  Bitboard checkersBB;
 
   // Board
   Piece board[64];
 
   // Piece counts
   int pieceCount[2][8]; // [color][pieceType]
-  
+
   // Piece lists
   Square pieceList[2][8][16]; // [color][pieceType][index]
   int index[64];
 
   // Other info
-  Color sideToMove;
-  int castleRights;
-  File initialKFile, initialKRFile, initialQRFile;
-  Square epSquare;
   Square kingSquare[2];
-  Move lastMove;
-  Key key, pawnKey, materialKey, history[MaxGameLength];
-  int rule50, gamePly;
-  Value mgValue, egValue;
+  Color sideToMove;
+  int gamePly;
+  Key history[MaxGameLength];
   Value npMaterial[2];
+  File initialKFile, initialKRFile, initialQRFile;
+  StateInfo startState;
+  StateInfo* st;
 
   // Static variables
   static int castleRightsMask[64];
@@ -491,32 +491,12 @@ inline int Position::piece_count(Color c, PieceType pt) const {
   return pieceCount[c][pt];
 }
 
-inline int Position::pawn_count(Color c) const {
-  return piece_count(c, PAWN);
-}
-
-inline int Position::knight_count(Color c) const {
-  return piece_count(c, KNIGHT);
-}
-
-inline int Position::bishop_count(Color c) const {
-  return piece_count(c, BISHOP);
-}
-
-inline int Position::rook_count(Color c) const {
-  return piece_count(c, ROOK);
-}
-
-inline int Position::queen_count(Color c) const {
-  return piece_count(c, QUEEN);
-}
-
 inline Square Position::piece_list(Color c, PieceType pt, int index) const {
   return pieceList[c][pt][index];
 }
 
 inline Square Position::ep_square() const {
-  return epSquare;
+  return st->epSquare;
 }
 
 inline Square Position::king_square(Color c) const {
@@ -524,11 +504,11 @@ inline Square Position::king_square(Color c) const {
 }
 
 inline bool Position::can_castle_kingside(Color side) const {
-  return castleRights & (1+int(side));
+  return st->castleRights & (1+int(side));
 }
 
 inline bool Position::can_castle_queenside(Color side) const {
-  return castleRights & (4+4*int(side));
+  return st->castleRights & (4+4*int(side));
 }
 
 inline bool Position::can_castle(Color side) const {
@@ -544,7 +524,12 @@ inline Square Position::initial_qr_square(Color c) const {
 }
 
 inline Bitboard Position::pawn_attacks(Color c, Square s) const {
-  return StepAttackBB[pawn_of_color(c)][s];
+  return StepAttackBB[piece_of_color_and_type(c, PAWN)][s];
+}
+
+template<>
+inline Bitboard Position::piece_attacks<PAWN>(Square s) const {
+  return StepAttackBB[piece_of_color_and_type(opposite_color(sideToMove), PAWN)][s];
 }
 
 template<>
@@ -572,12 +557,25 @@ inline Bitboard Position::piece_attacks<KING>(Square s) const {
   return StepAttackBB[KING][s];
 }
 
+inline Bitboard Position::pinned_pieces(Color c) const {
+  return st->pinned[c];
+}
+
+inline Bitboard Position::pinned_pieces(Color c, Bitboard& p) const {
+  p = st->pinners[c];
+  return st->pinned[c];
+}
+
+inline Bitboard Position::discovered_check_candidates(Color c) const {
+  return st->dcCandidates[c];
+}
+
 inline Bitboard Position::checkers() const {
-  return checkersBB;
+  return st->checkersBB;
 }
 
 inline bool Position::is_check() const {
-  return checkers() != EmptyBoardBB;
+  return st->checkersBB != EmptyBoardBB;
 }
 
 inline bool Position::pawn_attacks_square(Color c, Square f, Square t) const {
@@ -589,6 +587,16 @@ Bitboard Position::piece_attacks_square(Square f, Square t) const {
   return bit_is_set(piece_attacks<Piece>(f), t);
 }
 
+inline Bitboard Position::attacks_to(Square s, Color c) const {
+
+  return attacks_to(s) & pieces_of_color(c);
+}
+
+inline bool Position::square_is_attacked(Square s, Color c) const {
+
+  return attacks_to(s, c) != EmptyBoardBB;
+}
+
 inline bool Position::pawn_is_passed(Color c, Square s) const {
   return !(pawns(opposite_color(c)) & passed_pawn_mask(c, s));
 }
@@ -612,21 +620,23 @@ inline bool Position::file_is_half_open(Color c, File f) const {
 inline bool Position::square_is_weak(Square s, Color c) const {
   return !(pawns(c) & outpost_mask(opposite_color(c), s));
 }
-                                
+
 inline Key Position::get_key() const {
-  return key;
+  return st->key;
 }
 
 inline Key Position::get_pawn_key() const {
-  return pawnKey;
+  return st->pawnKey;
 }
 
 inline Key Position::get_material_key() const {
-  return materialKey;
+  return st->materialKey;
 }
 
-inline Value Position::mg_pst(Color c, PieceType pt, Square s) const {
-  return MgPieceSquareTable[piece_of_color_and_type(c, pt)][s];
+template<Position::GamePhase Phase>
+inline Value Position::pst(Color c, PieceType pt, Square s) const {
+  return (Phase == MidGame ? MgPieceSquareTable[piece_of_color_and_type(c, pt)][s]
+                           : EgPieceSquareTable[piece_of_color_and_type(c, pt)][s]);
 }
 
 inline Value Position::mg_pst_delta(Move m) const {
@@ -634,16 +644,12 @@ inline Value Position::mg_pst_delta(Move m) const {
         -MgPieceSquareTable[piece_on(move_from(m))][move_from(m)];
 }
 
-inline Value Position::eg_pst(Color c, PieceType pt, Square s) const {
-  return EgPieceSquareTable[piece_of_color_and_type(c, pt)][s];
-}
-
 inline Value Position::mg_value() const {
-  return mgValue;
+  return st->mgValue;
 }
 
 inline Value Position::eg_value() const {
-  return egValue;
+  return st->egValue;
 }
 
 inline Value Position::non_pawn_material(Color c) const {
@@ -663,7 +669,7 @@ inline Phase Position::game_phase() const {
   static const Value EndgameLimit = 4 * RookValueMidgame - Value(325);
 
   Value npm = non_pawn_material(WHITE) + non_pawn_material(BLACK);
-  
+
   if (npm >= MidgameLimit)
       return PHASE_MIDGAME;
   else if(npm <= EndgameLimit)
@@ -675,40 +681,40 @@ inline Phase Position::game_phase() const {
 inline bool Position::move_is_deep_pawn_push(Move m) const {
 
   Color c = side_to_move();
-  return   piece_on(move_from(m)) == pawn_of_color(c)
+  return   piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN)
         && relative_rank(c, move_to(m)) > RANK_4;
 }
 
 inline bool Position::move_is_pawn_push_to_7th(Move m) const {
 
   Color c = side_to_move();
-  return   piece_on(move_from(m)) == pawn_of_color(c)
+  return   piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN)
         && relative_rank(c, move_to(m)) == RANK_7;
 }
 
 inline bool Position::move_is_passed_pawn_push(Move m) const {
 
   Color c = side_to_move();
-  return   piece_on(move_from(m)) == pawn_of_color(c)
+  return   piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN)
         && pawn_is_passed(c, move_to(m));
 }
 
 inline bool Position::move_was_passed_pawn_push(Move m) const {
 
   Color c = opposite_color(side_to_move());
-  return   piece_on(move_to(m)) == pawn_of_color(c)
+  return   piece_on(move_to(m)) == piece_of_color_and_type(c, PAWN)
         && pawn_is_passed(c, move_to(m));
 }
 
 inline int Position::rule_50_counter() const {
 
-  return rule50;
+  return st->rule50;
 }
 
 inline bool Position::opposite_colored_bishops() const {
 
-  return   bishop_count(WHITE) == 1
-        && bishop_count(BLACK) == 1        
+  return   piece_count(WHITE, BISHOP) == 1
+        && piece_count(BLACK, BISHOP) == 1
         && square_color(piece_list(WHITE, BISHOP, 0)) != square_color(piece_list(BLACK, BISHOP, 0));
 }
 
@@ -716,6 +722,6 @@ inline bool Position::has_pawn_on_7th(Color c) const {
 
   return pawns(c) & relative_rank_bb(c, RANK_7);
 }
-                   
+
 
 #endif // !defined(POSITION_H_INCLUDED)