X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=d6c79ee181840553b6858c6dcfcf5416898db506;hp=af1e981cb3370af138d930d290b2d6d41e98db17;hb=2fe4e10b0bf11e98f66185c04084e87a1341af02;hpb=4c3a000211bea046dd9506bae748576ecf6368fa

diff --git a/src/position.h b/src/position.h
index af1e981c..d6c79ee1 100644
--- a/src/position.h
+++ b/src/position.h
@@ -26,40 +26,17 @@
 #include "move.h"
 #include "types.h"
 
-/// Maximum number of plies per game (220 should be enough, because the
-/// maximum search depth is 100, and during position setup we reset the
-/// move counter for every non-reversible move).
-const int MaxGameLength = 220;
 
-class Position;
-
-/// struct checkInfo is initialized at c'tor time and keeps
-/// info used to detect if a move gives check.
+/// The checkInfo struct is initialized at c'tor time and keeps info used
+/// to detect if a move gives check.
 
 struct CheckInfo {
 
     explicit CheckInfo(const Position&);
 
     Bitboard dcCandidates;
+    Bitboard pinned;
     Bitboard checkSq[8];
-    Square ksq;
-};
-
-/// Castle rights, encoded as bit fields
-
-enum CastleRights {
-  CASTLES_NONE = 0,
-  WHITE_OO     = 1,
-  BLACK_OO     = 2,
-  WHITE_OOO    = 4,
-  BLACK_OOO    = 8,
-  ALL_CASTLES  = 15
-};
-
-/// Game phase
-enum Phase {
-  PHASE_ENDGAME = 0,
-  PHASE_MIDGAME = 128
 };
 
 
@@ -67,17 +44,18 @@ enum Phase {
 /// 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.
+class Position;
 
 struct StateInfo {
   Key pawnKey, materialKey;
-  int castleRights, rule50, gamePly, pliesFromNull;
-  Square epSquare;
-  Score value;
   Value npMaterial[2];
+  int castleRights, rule50, pliesFromNull;
+  Score value;
+  Square epSquare;
 
-  PieceType capturedType;
   Key key;
   Bitboard checkersBB;
+  PieceType capturedType;
   StateInfo* previous;
 };
 
@@ -106,16 +84,12 @@ struct StateInfo {
 
 class Position {
 
-  Position(); // No default or copy c'tor allowed
-  Position(const Position& pos);
+  // No defaul, copy c'tor or assignment allowed, default c'tor will not be
+  // generated anyhow because of user-defined c'tors.
+  Position(const Position&);
+  Position& operator=(const Position&);
 
 public:
-  enum GamePhase {
-      MidGame,
-      EndGame
-  };
-
-  // Constructors
   Position(const Position& pos, int threadID);
   Position(const std::string& fen, bool isChess960, int threadID);
 
@@ -124,17 +98,9 @@ public:
   const std::string to_fen() const;
   void print(Move m = MOVE_NONE) const;
 
-  // Copying
-  void flip();
-
   // The piece on a given square
   Piece piece_on(Square s) const;
-  PieceType type_of_piece_on(Square s) const;
-  Color color_of_piece_on(Square s) const;
   bool square_is_empty(Square s) const;
-  bool square_is_occupied(Square s) const;
-  Value midgame_value_of_piece_on(Square s) const;
-  Value endgame_value_of_piece_on(Square s) const;
 
   // Side to move
   Color side_to_move() const;
@@ -142,7 +108,7 @@ public:
   // Bitboard representation of the position
   Bitboard empty_squares() const;
   Bitboard occupied_squares() const;
-  Bitboard pieces_of_color(Color c) const;
+  Bitboard pieces(Color c) const;
   Bitboard pieces(PieceType pt) const;
   Bitboard pieces(PieceType pt, Color c) const;
   Bitboard pieces(PieceType pt1, PieceType pt2) const;
@@ -158,23 +124,20 @@ public:
   Square king_square(Color c) const;
 
   // Castling rights
-  bool can_castle_kingside(Color c) const;
-  bool can_castle_queenside(Color c) const;
+  bool can_castle(CastleRight f) const;
   bool can_castle(Color c) const;
-  Square initial_kr_square(Color c) const;
-  Square initial_qr_square(Color c) const;
+  Square castle_rook_square(CastleRight f) const;
 
   // Bitboards for pinned pieces and discovered check candidates
-  Bitboard discovered_check_candidates(Color c) const;
-  Bitboard pinned_pieces(Color c) const;
+  Bitboard discovered_check_candidates() const;
+  Bitboard pinned_pieces() const;
 
   // Checking pieces and under check information
   Bitboard checkers() const;
   bool in_check() const;
 
   // Piece lists
-  Square piece_list(Color c, PieceType pt, int index) const;
-  const Square* piece_list_begin(Color c, PieceType pt) const;
+  const Square* piece_list(Color c, PieceType pt) const;
 
   // Information about attacks to or from a given square
   Bitboard attackers_to(Square s) const;
@@ -185,13 +148,13 @@ public:
   template<PieceType> Bitboard attacks_from(Square s, Color c) const;
 
   // Properties of moves
-  bool pl_move_is_legal(Move m, Bitboard pinned) const;
-  bool move_is_pl(const Move m) const;
-  bool move_gives_check(Move m) const;
   bool move_gives_check(Move m, const CheckInfo& ci) const;
-  bool move_is_capture(Move m) const;
-  bool move_is_passed_pawn_push(Move m) const;
   bool move_attacks_square(Move m, Square s) const;
+  bool pl_move_is_legal(Move m, Bitboard pinned) const;
+  bool is_pseudo_legal(const Move m) const;
+  bool is_capture(Move m) const;
+  bool is_capture_or_promotion(Move m) const;
+  bool is_passed_pawn_push(Move m) const;
 
   // Piece captured with previous moves
   PieceType captured_piece_type() const;
@@ -199,11 +162,7 @@ public:
   // Information about pawns
   bool pawn_is_passed(Color c, Square s) const;
 
-  // Weak squares
-  bool square_is_weak(Square s, Color c) const;
-
   // Doing and undoing moves
-  void do_setup_move(Move m);
   void do_move(Move m, StateInfo& st);
   void do_move(Move m, StateInfo& st, const CheckInfo& ci, bool moveIsCheck);
   void undo_move(Move m);
@@ -223,13 +182,13 @@ public:
   // Incremental evaluation
   Score value() const;
   Value non_pawn_material(Color c) const;
-  static Score pst_delta(Piece piece, Square from, Square to);
+  Score pst_delta(Piece piece, Square from, Square to) const;
 
   // Game termination checks
   bool is_mate() const;
-  bool is_draw() const;
+  template<bool SkipRepetition> bool is_draw() const;
 
-  // Number of plies from starting position
+  // Plies from start position to the beginning of search
   int startpos_ply_counter() const;
 
   // Other properties of the position
@@ -244,31 +203,27 @@ public:
   void set_nodes_searched(int64_t n);
 
   // Position consistency check, for debugging
-  bool is_ok(int* failedStep = NULL) const;
+  bool pos_is_ok(int* failedStep = NULL) const;
+  void flip_me();
 
-  // Static member functions
-  static void init_zobrist();
-  static void init_piece_square_tables();
+  // Global initialization
+  static void init();
 
 private:
 
   // Initialization helper functions (used while setting up a position)
   void clear();
-  void detach();
   void put_piece(Piece p, Square s);
-  void do_allow_oo(Color c);
-  void do_allow_ooo(Color c);
-  bool set_castling_rights(char token);
-  bool move_is_pl_slow(const Move m) const;
+  void set_castle_right(Square ksq, Square rsq);
+  bool move_is_legal(const Move m) const;
 
   // Helper functions for doing and undoing moves
   void do_capture_move(Key& key, PieceType capture, Color them, Square to, bool ep);
   void do_castle_move(Move m);
   void undo_castle_move(Move m);
-  void find_checkers();
 
   template<bool FindPinned>
-  Bitboard hidden_checkers(Color c) const;
+  Bitboard hidden_checkers() const;
 
   // Computing hash keys from scratch (for initialization and debugging)
   Key compute_key() const;
@@ -276,45 +231,42 @@ private:
   Key compute_material_key() const;
 
   // Computing incremental evaluation scores and material counts
-  static Score pst(Color c, PieceType pt, Square s);
+  Score pst(Piece p, Square s) const;
   Score compute_value() const;
   Value compute_non_pawn_material(Color c) const;
 
   // Board
-  Piece board[64];
+  Piece board[64];             // [square]
 
   // Bitboards
-  Bitboard byTypeBB[8], byColorBB[2];
+  Bitboard byTypeBB[8];        // [pieceType]
+  Bitboard byColorBB[2];       // [color]
 
   // Piece counts
-  int pieceCount[2][8]; // [color][pieceType]
+  int pieceCount[2][8];        // [color][pieceType]
 
   // Piece lists
-  Square pieceList[2][8][16]; // [color][pieceType][index]
-  int index[64]; // [square]
+  Square pieceList[2][8][16];  // [color][pieceType][index]
+  int index[64];               // [square]
 
   // Other info
-  Color sideToMove;
-  Key history[MaxGameLength];
-  int castleRightsMask[64];
+  int castleRightsMask[64];    // [square]
+  Square castleRookSquare[16]; // [castleRight]
   StateInfo startState;
-  File initialKFile, initialKRFile, initialQRFile;
-  bool chess960;
-  int startPosPlyCounter;
-  int threadID;
   int64_t nodes;
+  int startPosPly;
+  Color sideToMove;
+  int threadID;
   StateInfo* st;
+  int chess960;
 
   // Static variables
-  static Key zobrist[2][8][64];
-  static Key zobEp[64];
-  static Key zobCastle[16];
+  static Score pieceSquareTable[16][64]; // [piece][square]
+  static Key zobrist[2][8][64];          // [color][pieceType][square]/[piece count]
+  static Key zobEp[64];                  // [square]
+  static Key zobCastle[16];              // [castleRight]
   static Key zobSideToMove;
-  static Score PieceSquareTable[16][64];
   static Key zobExclusion;
-  static const Value seeValues[8];
-  static const Value PieceValueMidgame[17];
-  static const Value PieceValueEndgame[17];
 };
 
 inline int64_t Position::nodes_searched() const {
@@ -329,28 +281,8 @@ inline Piece Position::piece_on(Square s) const {
   return board[s];
 }
 
-inline Color Position::color_of_piece_on(Square s) const {
-  return color_of_piece(piece_on(s));
-}
-
-inline PieceType Position::type_of_piece_on(Square s) const {
-  return type_of_piece(piece_on(s));
-}
-
 inline bool Position::square_is_empty(Square s) const {
-  return piece_on(s) == PIECE_NONE;
-}
-
-inline bool Position::square_is_occupied(Square s) const {
-  return !square_is_empty(s);
-}
-
-inline Value Position::midgame_value_of_piece_on(Square s) const {
-  return PieceValueMidgame[piece_on(s)];
-}
-
-inline Value Position::endgame_value_of_piece_on(Square s) const {
-  return PieceValueEndgame[piece_on(s)];
+  return board[s] == PIECE_NONE;
 }
 
 inline Color Position::side_to_move() const {
@@ -362,10 +294,10 @@ inline Bitboard Position::occupied_squares() const {
 }
 
 inline Bitboard Position::empty_squares() const {
-  return ~occupied_squares();
+  return ~byTypeBB[0];
 }
 
-inline Bitboard Position::pieces_of_color(Color c) const {
+inline Bitboard Position::pieces(Color c) const {
   return byColorBB[c];
 }
 
@@ -389,11 +321,7 @@ inline int Position::piece_count(Color c, PieceType pt) const {
   return pieceCount[c][pt];
 }
 
-inline Square Position::piece_list(Color c, PieceType pt, int idx) const {
-  return pieceList[c][pt][idx];
-}
-
-inline const Square* Position::piece_list_begin(Color c, PieceType pt) const {
+inline const Square* Position::piece_list(Color c, PieceType pt) const {
   return pieceList[c][pt];
 }
 
@@ -405,24 +333,16 @@ inline Square Position::king_square(Color c) const {
   return pieceList[c][KING][0];
 }
 
-inline bool Position::can_castle_kingside(Color side) const {
-  return st->castleRights & (1+int(side));
-}
-
-inline bool Position::can_castle_queenside(Color side) const {
-  return st->castleRights & (4+4*int(side));
-}
-
-inline bool Position::can_castle(Color side) const {
-  return can_castle_kingside(side) || can_castle_queenside(side);
+inline bool Position::can_castle(CastleRight f) const {
+  return st->castleRights & f;
 }
 
-inline Square Position::initial_kr_square(Color c) const {
-  return relative_square(c, make_square(initialKRFile, RANK_1));
+inline bool Position::can_castle(Color c) const {
+  return st->castleRights & ((WHITE_OO | WHITE_OOO) << c);
 }
 
-inline Square Position::initial_qr_square(Color c) const {
-  return relative_square(c, make_square(initialQRFile, RANK_1));
+inline Square Position::castle_rook_square(CastleRight f) const {
+  return castleRookSquare[f];
 }
 
 template<>
@@ -450,20 +370,24 @@ inline Bitboard Position::attacks_from<QUEEN>(Square s) const {
   return attacks_from<ROOK>(s) | attacks_from<BISHOP>(s);
 }
 
+inline Bitboard Position::attacks_from(Piece p, Square s) const {
+  return attacks_from(p, s, occupied_squares());
+}
+
+inline Bitboard Position::attackers_to(Square s) const {
+  return attackers_to(s, occupied_squares());
+}
+
 inline Bitboard Position::checkers() const {
   return st->checkersBB;
 }
 
 inline bool Position::in_check() const {
-  return st->checkersBB != EmptyBoardBB;
+  return st->checkersBB != 0;
 }
 
 inline bool Position::pawn_is_passed(Color c, Square s) const {
-  return !(pieces(PAWN, opposite_color(c)) & passed_pawn_mask(c, s));
-}
-
-inline bool Position::square_is_weak(Square s, Color c) const {
-  return !(pieces(PAWN, opposite_color(c)) & attack_span_mask(c, s));
+  return !(pieces(PAWN, flip(c)) & passed_pawn_mask(c, s));
 }
 
 inline Key Position::get_key() const {
@@ -482,12 +406,12 @@ inline Key Position::get_material_key() const {
   return st->materialKey;
 }
 
-inline Score Position::pst(Color c, PieceType pt, Square s) {
-  return PieceSquareTable[make_piece(c, pt)][s];
+inline Score Position::pst(Piece p, Square s) const {
+  return pieceSquareTable[p][s];
 }
 
-inline Score Position::pst_delta(Piece piece, Square from, Square to) {
-  return PieceSquareTable[piece][to] - PieceSquareTable[piece][from];
+inline Score Position::pst_delta(Piece piece, Square from, Square to) const {
+  return pieceSquareTable[piece][to] - pieceSquareTable[piece][from];
 }
 
 inline Score Position::value() const {
@@ -498,21 +422,21 @@ inline Value Position::non_pawn_material(Color c) const {
   return st->npMaterial[c];
 }
 
-inline bool Position::move_is_passed_pawn_push(Move m) const {
+inline bool Position::is_passed_pawn_push(Move m) const {
 
-  Color c = side_to_move();
-  return   piece_on(move_from(m)) == make_piece(c, PAWN)
-        && pawn_is_passed(c, move_to(m));
+  return   board[move_from(m)] == make_piece(sideToMove, PAWN)
+        && pawn_is_passed(sideToMove, move_to(m));
 }
 
 inline int Position::startpos_ply_counter() const {
-  return startPosPlyCounter;
+  return startPosPly + st->pliesFromNull; // HACK
 }
 
 inline bool Position::opposite_colored_bishops() const {
 
-  return   piece_count(WHITE, BISHOP) == 1 && piece_count(BLACK, BISHOP) == 1
-        && opposite_color_squares(piece_list(WHITE, BISHOP, 0), piece_list(BLACK, BISHOP, 0));
+  return   pieceCount[WHITE][BISHOP] == 1
+        && pieceCount[BLACK][BISHOP] == 1
+        && opposite_colors(pieceList[WHITE][BISHOP][0], pieceList[BLACK][BISHOP][0]);
 }
 
 inline bool Position::has_pawn_on_7th(Color c) const {
@@ -523,10 +447,17 @@ inline bool Position::is_chess960() const {
   return chess960;
 }
 
-inline bool Position::move_is_capture(Move m) const {
+inline bool Position::is_capture_or_promotion(Move m) const {
 
-  assert (m != MOVE_NONE && m != MOVE_NULL);
-  return !move_is_special(m) ? !square_is_empty(move_to(m)) : move_is_ep(m);
+  assert(is_ok(m));
+  return is_special(m) ? !is_castle(m) : !square_is_empty(move_to(m));
+}
+
+inline bool Position::is_capture(Move m) const {
+
+  // Note that castle is coded as "king captures the rook"
+  assert(is_ok(m));
+  return (!square_is_empty(move_to(m)) && !is_castle(m)) || is_enpassant(m);
 }
 
 inline PieceType Position::captured_piece_type() const {
@@ -537,12 +468,4 @@ inline int Position::thread() const {
   return threadID;
 }
 
-inline void Position::do_allow_oo(Color c) {
-  st->castleRights |= (1 + int(c));
-}
-
-inline void Position::do_allow_ooo(Color c) {
-  st->castleRights |= (4 + 4*int(c));
-}
-
 #endif // !defined(POSITION_H_INCLUDED)