/*
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
//// Types
////
+/// struct checkInfo is initialized at c'tor time and keeps
+/// info used to detect if a move gives check.
+
+struct CheckInfo {
+
+ CheckInfo(const Position&);
+
+ Bitboard dcCandidates;
+ Bitboard checkSq[8];
+ Square ksq;
+};
+
/// Castle rights, encoded as bit fields
enum CastleRights {
/// must be passed as a parameter.
struct StateInfo {
- Key key, pawnKey, materialKey;
- int castleRights, rule50, pliesFromNull;
+ Key pawnKey, materialKey;
+ int castleRights, rule50, gamePly, pliesFromNull;
Square epSquare;
- Value mgValue, egValue;
+ Score value;
Value npMaterial[2];
PieceType capture;
+ Key key;
Bitboard checkersBB;
StateInfo* previous;
};
};
// Constructors
- Position() {}
- Position(const Position& pos);
- Position(const std::string& fen);
+ Position();
+ explicit Position(const Position& pos);
+ explicit Position(const std::string& fen);
// Text input/output
void from_fen(const std::string& fen);
void print(Move m = MOVE_NONE) const;
// Copying
- void copy(const Position& pos);
void flipped_copy(const Position& pos);
// The piece on a given square
bool pl_move_is_legal(Move m, Bitboard pinned) const;
bool pl_move_is_evasion(Move m, Bitboard pinned) const;
bool move_is_check(Move m) const;
- bool move_is_check(Move m, Bitboard dcCandidates) const;
+ bool move_is_check(Move m, const CheckInfo& ci) const;
bool move_is_capture(Move m) const;
bool move_is_capture_or_promotion(Move m) const;
bool move_is_passed_pawn_push(Move m) const;
bool move_attacks_square(Move m, Square s) const;
+ // Piece captured with previous moves
+ PieceType captured_piece() const;
+
// Information about pawns
bool pawn_is_passed(Color c, Square s) const;
- static bool pawn_is_passed(Bitboard theirPawns, Color c, Square s);
- static bool pawn_is_isolated(Bitboard ourPawns, Square s);
- static bool pawn_is_doubled(Bitboard ourPawns, Color c, Square s);
// Weak squares
bool square_is_weak(Square s, Color c) const;
// Doing and undoing moves
- void saveState();
+ void detach();
void do_move(Move m, StateInfo& st);
- void do_move(Move m, StateInfo& st, Bitboard dcCandidates);
+ void do_move(Move m, StateInfo& st, const CheckInfo& ci, bool moveIsCheck);
void undo_move(Move m);
void do_null_move(StateInfo& st);
void undo_null_move();
// Accessing hash keys
Key get_key() const;
+ Key get_exclusion_key() const;
Key get_pawn_key() const;
Key get_material_key() const;
// Incremental evaluation
- Value mg_value() const;
- Value eg_value() const;
+ Score value() const;
Value non_pawn_material(Color c) const;
- Phase game_phase() const;
- template<GamePhase> Value pst_delta(Piece piece, Square from, Square to) const;
+ Score pst_delta(Piece piece, Square from, Square to) const;
// Game termination checks
bool is_mate() const;
void allow_ooo(Color c);
// Helper functions for doing and undoing moves
- void do_capture_move(Bitboard& key, PieceType capture, Color them, Square to, bool ep);
+ 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<PieceType Piece>
- void update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, Square to, Bitboard dcCandidates);
-
template<bool FindPinned>
Bitboard hidden_checkers(Color c) const;
Key compute_material_key() const;
// Computing incremental evaluation scores and material counts
- template<GamePhase> Value pst(Color c, PieceType pt, Square s) const;
- template<GamePhase> Value compute_value() const;
+ Score pst(Color c, PieceType pt, Square s) const;
+ Score compute_value() const;
Value compute_non_pawn_material(Color c) const;
// Board
// Other info
Color sideToMove;
- int gamePly;
Key history[MaxGameLength];
- File initialKFile, initialKRFile, initialQRFile;
+ int castleRightsMask[64];
StateInfo startState;
+ File initialKFile, initialKRFile, initialQRFile;
StateInfo* st;
// Static variables
- static int castleRightsMask[64];
static Key zobrist[2][8][64];
static Key zobEp[64];
static Key zobCastle[16];
- static Key zobMaterial[2][8][16];
static Key zobSideToMove;
- static Value MgPieceSquareTable[16][64];
- static Value EgPieceSquareTable[16][64];
+ static Score PieceSquareTable[16][64];
+ static Key zobExclusion;
};
return pieceCount[c][pt];
}
-inline Square Position::piece_list(Color c, PieceType pt, int index) const {
- return pieceList[c][pt][index];
+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 {
return !(pieces(PAWN, opposite_color(c)) & passed_pawn_mask(c, s));
}
-inline bool Position::pawn_is_passed(Bitboard theirPawns, Color c, Square s) {
- return !(theirPawns & passed_pawn_mask(c, s));
-}
-
-inline bool Position::pawn_is_isolated(Bitboard ourPawns, Square s) {
- return !(ourPawns & neighboring_files_bb(s));
-}
-
-inline bool Position::pawn_is_doubled(Bitboard ourPawns, Color c, Square s) {
- return ourPawns & squares_behind(c, s);
-}
-
inline bool Position::square_is_weak(Square s, Color c) const {
- return !(pieces(PAWN, c) & outpost_mask(opposite_color(c), s));
+ return !(pieces(PAWN, opposite_color(c)) & attack_span_mask(c, s));
}
inline Key Position::get_key() const {
return st->key;
}
+inline Key Position::get_exclusion_key() const {
+ return st->key ^ zobExclusion;
+}
+
inline Key Position::get_pawn_key() const {
return st->pawnKey;
}
return st->materialKey;
}
-template<Position::GamePhase Ph>
-inline Value Position::pst(Color c, PieceType pt, Square s) const {
- return (Ph == MidGame ? MgPieceSquareTable[piece_of_color_and_type(c, pt)][s]
- : EgPieceSquareTable[piece_of_color_and_type(c, pt)][s]);
+inline Score Position::pst(Color c, PieceType pt, Square s) const {
+ return PieceSquareTable[piece_of_color_and_type(c, pt)][s];
}
-template<Position::GamePhase Ph>
-inline Value Position::pst_delta(Piece piece, Square from, Square to) const {
- return (Ph == MidGame ? MgPieceSquareTable[piece][to] - MgPieceSquareTable[piece][from]
- : EgPieceSquareTable[piece][to] - EgPieceSquareTable[piece][from]);
+inline Score Position::pst_delta(Piece piece, Square from, Square to) const {
+ return PieceSquareTable[piece][to] - PieceSquareTable[piece][from];
}
-inline Value Position::mg_value() const {
- return st->mgValue;
-}
-
-inline Value Position::eg_value() const {
- return st->egValue;
+inline Score Position::value() const {
+ return st->value;
}
inline Value Position::non_pawn_material(Color c) const {
return st->npMaterial[c];
}
-inline Phase Position::game_phase() const {
-
- // Values modified by Joona Kiiski
- static const Value MidgameLimit = Value(15581);
- static const Value EndgameLimit = Value(3998);
-
- Value npm = non_pawn_material(WHITE) + non_pawn_material(BLACK);
-
- if (npm >= MidgameLimit)
- return PHASE_MIDGAME;
- else if(npm <= EndgameLimit)
- return PHASE_ENDGAME;
- else
- return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
-}
-
inline bool Position::move_is_passed_pawn_push(Move m) const {
Color c = side_to_move();
return (m & (0x1F << 12)) ? !move_is_castle(m) : !square_is_empty(move_to(m));
}
+inline PieceType Position::captured_piece() const {
+ return st->capture;
+}
+
#endif // !defined(POSITION_H_INCLUDED)