/*
- 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/>.
*/
#if !defined(POSITION_H_INCLUDED)
#define POSITION_H_INCLUDED
+// Disable a silly and noisy warning from MSVC compiler
+#if defined(_MSC_VER)
+
+// Forcing value to bool 'true' or 'false' (performance warning)
+#pragma warning(disable: 4800)
+
+#endif
+
////
//// Includes
////
////
/// 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
/// Castle rights, encoded as bit fields:
enum CastleRights {
- NO_CASTLES = 0,
- WHITE_OO = 1, BLACK_OO = 2,
- WHITE_OOO = 4, BLACK_OOO = 8,
+ NO_CASTLES = 0,
+ WHITE_OO = 1,
+ BLACK_OO = 2,
+ WHITE_OOO = 4,
+ BLACK_OOO = 8,
ALL_CASTLES = 15
};
Key key, pawnKey, materialKey;
int rule50;
Move lastMove;
- PieceType capture;
Value mgValue, egValue;
+ PieceType capture;
};
/// 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
class Position {
friend class MaterialInfo;
+ friend class EndgameFunctions;
public:
// Constructors
- Position();
- Position(const Position &pos);
- Position(const std::string &fen);
+ Position() {};
+ 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);
// 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;
Bitboard sliding_attacks(Square s, Direction d) const;
Bitboard ray_attacks(Square s, SignedDirection d) const;
Bitboard pawn_attacks(Color c, Square s) const;
- Bitboard white_pawn_attacks(Square s) const;
- Bitboard black_pawn_attacks(Square s) const;
- Bitboard knight_attacks(Square s) const;
- Bitboard bishop_attacks(Square s) const;
- Bitboard rook_attacks(Square s) const;
- Bitboard queen_attacks(Square s) const;
- Bitboard king_attacks(Square s) const;
+
+ template<PieceType>
+ Bitboard piece_attacks(Square s) const;
// Bitboards for pinned pieces and discovered check candidates
Bitboard discovered_check_candidates(Color c) const;
// Checking pieces
Bitboard checkers() const;
- // Piece lists:
+ // Piece lists
Square piece_list(Color c, PieceType pt, int index) const;
- Square pawn_list(Color c, int index) const;
- Square knight_list(Color c, int index) const;
- Square bishop_list(Color c, int index) const;
- Square rook_list(Color c, int index) const;
- Square queen_list(Color c, int index) const;
// Attack information for a given square
bool square_is_attacked(Square s, Color c) const;
Bitboard attacks_to(Square s) const;
Bitboard attacks_to(Square s, Color c) const;
bool is_check() const;
- bool piece_attacks_square(Square f, Square t) const;
- bool white_pawn_attacks_square(Square f, Square t) const;
- bool black_pawn_attacks_square(Square f, Square t) const;
- bool knight_attacks_square(Square f, Square t) const;
- bool bishop_attacks_square(Square f, Square t) const;
- bool rook_attacks_square(Square f, Square t) const;
- bool queen_attacks_square(Square f, Square t) const;
- bool king_attacks_square(Square f, Square t) const;
+ bool pawn_attacks_square(Color c, Square f, Square t) const;
+
+ 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
// 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 pl_move_is_legal(Move m, Bitboard pinned) 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;
bool move_is_passed_pawn_push(Move m) const;
bool move_was_passed_pawn_push(Move m) const;
// 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;
Value eg_value() const;
Value non_pawn_material(Color c) const;
Phase game_phase() const;
+ 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
// Reset the gamePly variable to 0
void reset_game_ply();
-
+
// Position consistency check, for debugging
- bool is_ok() const;
+ bool is_ok(int* failedStep = NULL) const;
// Static member functions:
static void init_zobrist();
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_ep_move(Move m);
void undo_ep_move(Move m);
void find_checkers();
+ 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) const;
+
// Computing hash keys from scratch (for initialization and debugging)
Key compute_key() const;
Key compute_pawn_key() const;
// Piece counts
int pieceCount[2][8]; // [color][pieceType]
-
+
// Piece lists
Square pieceList[2][8][16]; // [color][pieceType][index]
int index[64];
}
inline Color Position::color_of_piece_on(Square s) const {
- return color_of_piece(this->piece_on(s));
+ return color_of_piece(piece_on(s));
}
inline PieceType Position::type_of_piece_on(Square s) const {
- return type_of_piece(this->piece_on(s));
+ return type_of_piece(piece_on(s));
}
inline bool Position::square_is_empty(Square s) const {
- return this->piece_on(s) == EMPTY;
+ return piece_on(s) == EMPTY;
}
inline bool Position::square_is_occupied(Square s) const {
- return !this->square_is_empty(s);
+ return !square_is_empty(s);
}
inline Value Position::midgame_value_of_piece_on(Square s) const {
- return piece_value_midgame(this->piece_on(s));
+ return piece_value_midgame(piece_on(s));
}
inline Value Position::endgame_value_of_piece_on(Square s) const {
- return piece_value_endgame(this->piece_on(s));
+ return piece_value_endgame(piece_on(s));
}
inline Color Position::side_to_move() const {
}
inline Bitboard Position::empty_squares() const {
- return ~(this->occupied_squares());
+ return ~(occupied_squares());
}
inline Bitboard Position::pieces_of_color(Color c) const {
return byTypeBB[pt];
}
-inline Bitboard Position::pieces_of_color_and_type(Color c, PieceType pt)
- const {
- return this->pieces_of_color(c) & this->pieces_of_type(pt);
+inline Bitboard Position::pieces_of_color_and_type(Color c, PieceType pt) const {
+ return pieces_of_color(c) & pieces_of_type(pt);
}
inline Bitboard Position::pawns() const {
- return this->pieces_of_type(PAWN);
+ return pieces_of_type(PAWN);
}
inline Bitboard Position::knights() const {
- return this->pieces_of_type(KNIGHT);
+ return pieces_of_type(KNIGHT);
}
inline Bitboard Position::bishops() const {
- return this->pieces_of_type(BISHOP);
+ return pieces_of_type(BISHOP);
}
inline Bitboard Position::rooks() const {
- return this->pieces_of_type(ROOK);
+ return pieces_of_type(ROOK);
}
inline Bitboard Position::queens() const {
- return this->pieces_of_type(QUEEN);
+ return pieces_of_type(QUEEN);
}
inline Bitboard Position::kings() const {
- return this->pieces_of_type(KING);
+ return pieces_of_type(KING);
}
inline Bitboard Position::rooks_and_queens() const {
- return this->rooks() | this->queens();
+ return rooks() | queens();
}
inline Bitboard Position::bishops_and_queens() const {
- return this->bishops() | this->queens();
+ return bishops() | queens();
}
inline Bitboard Position::sliders() const {
- return this->bishops() | this->queens() | this->rooks();
+ return bishops() | queens() | rooks();
}
inline Bitboard Position::pawns(Color c) const {
- return this->pieces_of_color_and_type(c, PAWN);
+ return pieces_of_color_and_type(c, PAWN);
}
inline Bitboard Position::knights(Color c) const {
- return this->pieces_of_color_and_type(c, KNIGHT);
+ return pieces_of_color_and_type(c, KNIGHT);
}
inline Bitboard Position::bishops(Color c) const {
- return this->pieces_of_color_and_type(c, BISHOP);
+ return pieces_of_color_and_type(c, BISHOP);
}
inline Bitboard Position::rooks(Color c) const {
- return this->pieces_of_color_and_type(c, ROOK);
+ return pieces_of_color_and_type(c, ROOK);
}
inline Bitboard Position::queens(Color c) const {
- return this->pieces_of_color_and_type(c, QUEEN);
+ return pieces_of_color_and_type(c, QUEEN);
}
inline Bitboard Position::kings(Color c) const {
- return this->pieces_of_color_and_type(c, KING);
+ return pieces_of_color_and_type(c, KING);
}
inline Bitboard Position::rooks_and_queens(Color c) const {
- return this->rooks_and_queens() & this->pieces_of_color(c);
+ return rooks_and_queens() & pieces_of_color(c);
}
inline Bitboard Position::bishops_and_queens(Color c) const {
- return this->bishops_and_queens() & this->pieces_of_color(c);
+ return bishops_and_queens() & pieces_of_color(c);
}
inline Bitboard Position::sliders_of_color(Color c) const {
- return this->sliders() & this->pieces_of_color(c);
+ return sliders() & pieces_of_color(c);
}
inline int Position::piece_count(Color c, PieceType pt) const {
return pieceCount[c][pt];
}
-inline int Position::pawn_count(Color c) const {
- return this->piece_count(c, PAWN);
-}
-
-inline int Position::knight_count(Color c) const {
- return this->piece_count(c, KNIGHT);
-}
-
-inline int Position::bishop_count(Color c) const {
- return this->piece_count(c, BISHOP);
-}
-
-inline int Position::rook_count(Color c) const {
- return this->piece_count(c, ROOK);
-}
-
-inline int Position::queen_count(Color c) const {
- return this->piece_count(c, QUEEN);
-}
-
inline Square Position::piece_list(Color c, PieceType pt, int index) const {
return pieceList[c][pt][index];
}
-inline Square Position::pawn_list(Color c, int index) const {
- return this->piece_list(c, PAWN, index);
-}
-
-inline Square Position::knight_list(Color c, int index) const {
- return this->piece_list(c, KNIGHT, index);
-}
-
-inline Square Position::bishop_list(Color c, int index) const {
- return this->piece_list(c, BISHOP, index);
-}
-
-inline Square Position::rook_list(Color c, int index) const {
- return this->piece_list(c, ROOK, index);
-}
-
-inline Square Position::queen_list(Color c, int index) const {
- return this->piece_list(c, QUEEN, index);
-}
-
inline Square Position::ep_square() const {
return epSquare;
}
return StepAttackBB[pawn_of_color(c)][s];
}
-inline Bitboard Position::white_pawn_attacks(Square s) const {
- return this->pawn_attacks(WHITE, s);
-}
-
-inline Bitboard Position::black_pawn_attacks(Square s) const {
- return this->pawn_attacks(BLACK, s);
+template<>
+inline Bitboard Position::piece_attacks<PAWN>(Square s) const {
+ return StepAttackBB[pawn_of_color(opposite_color(sideToMove))][s];
}
-inline Bitboard Position::knight_attacks(Square s) const {
+template<>
+inline Bitboard Position::piece_attacks<KNIGHT>(Square s) const {
return StepAttackBB[KNIGHT][s];
}
-inline Bitboard Position::rook_attacks(Square s) const {
- return rook_attacks_bb(s, this->occupied_squares());
+template<>
+inline Bitboard Position::piece_attacks<BISHOP>(Square s) const {
+ return bishop_attacks_bb(s, occupied_squares());
}
-inline Bitboard Position::bishop_attacks(Square s) const {
- return bishop_attacks_bb(s, this->occupied_squares());
+template<>
+inline Bitboard Position::piece_attacks<ROOK>(Square s) const {
+ return rook_attacks_bb(s, occupied_squares());
}
-inline Bitboard Position::queen_attacks(Square s) const {
- return this->rook_attacks(s) | this->bishop_attacks(s);
+template<>
+inline Bitboard Position::piece_attacks<QUEEN>(Square s) const {
+ return piece_attacks<ROOK>(s) | piece_attacks<BISHOP>(s);
}
-inline Bitboard Position::king_attacks(Square s) const {
+template<>
+inline Bitboard Position::piece_attacks<KING>(Square s) const {
return StepAttackBB[KING][s];
}
}
inline bool Position::is_check() const {
- return this->checkers() != EmptyBoardBB;
+ return checkersBB != EmptyBoardBB;
}
-inline bool Position::white_pawn_attacks_square(Square f, Square t) const {
- return bit_is_set(this->white_pawn_attacks(f), t);
+inline bool Position::pawn_attacks_square(Color c, Square f, Square t) const {
+ return bit_is_set(pawn_attacks(c, f), t);
}
-inline bool Position::black_pawn_attacks_square(Square f, Square t) const {
- return bit_is_set(this->black_pawn_attacks(f), t);
+template<PieceType Piece>
+Bitboard Position::piece_attacks_square(Square f, Square t) const {
+ return bit_is_set(piece_attacks<Piece>(f), t);
}
-inline bool Position::knight_attacks_square(Square f, Square t) const {
- return bit_is_set(this->knight_attacks(f), t);
-}
+inline Bitboard Position::attacks_to(Square s, Color c) const {
-inline bool Position::bishop_attacks_square(Square f, Square t) const {
- return bit_is_set(this->bishop_attacks(f), t);
+ return attacks_to(s) & pieces_of_color(c);
}
-inline bool Position::rook_attacks_square(Square f, Square t) const {
- return bit_is_set(this->rook_attacks(f), t);
-}
+inline bool Position::square_is_attacked(Square s, Color c) const {
-inline bool Position::queen_attacks_square(Square f, Square t) const {
- return bit_is_set(this->queen_attacks(f), t);
-}
-
-inline bool Position::king_attacks_square(Square f, Square t) const {
- return bit_is_set(this->king_attacks(f), t);
+ return attacks_to(s, c) != EmptyBoardBB;
}
inline bool Position::pawn_is_passed(Color c, Square s) const {
- return !(this->pawns(opposite_color(c)) & passed_pawn_mask(c, s));
+ return !(pawns(opposite_color(c)) & passed_pawn_mask(c, s));
}
inline bool Position::pawn_is_isolated(Color c, Square s) const {
- return !(this->pawns(c) & neighboring_files_bb(s));
+ return !(pawns(c) & neighboring_files_bb(s));
}
inline bool Position::pawn_is_doubled(Color c, Square s) const {
- return this->pawns(c) & squares_behind(c, s);
+ return pawns(c) & squares_behind(c, s);
}
inline bool Position::file_is_open(File f) const {
- return !(this->pawns() & file_bb(f));
+ return !(pawns() & file_bb(f));
}
inline bool Position::file_is_half_open(Color c, File f) const {
- return !(this->pawns(c) & file_bb(f));
+ return !(pawns(c) & file_bb(f));
}
inline bool Position::square_is_weak(Square s, Color c) const {
- return !(this->pawns(c) & outpost_mask(opposite_color(c), s));
+ return !(pawns(c) & outpost_mask(opposite_color(c), s));
}
-
+
inline Key Position::get_key() const {
return key;
}
return MgPieceSquareTable[piece_of_color_and_type(c, pt)][s];
}
+inline Value Position::mg_pst_delta(Move m) const {
+ return MgPieceSquareTable[piece_on(move_from(m))][move_to(m)]
+ -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];
}
// The purpose of the Value(325) terms below is to make sure the difference
// between MidgameLimit and EndgameLimit is a power of 2, which should make
// the division at the end of the function a bit faster.
+ static const Value MidgameLimit = 2 * QueenValueMidgame
+ + 2 * RookValueMidgame
+ + 6 * BishopValueMidgame
+ + Value(325);
+
+ static const Value EndgameLimit = 4 * RookValueMidgame - Value(325);
- static const Value MidgameLimit =
- 2*QueenValueMidgame+2*RookValueMidgame+6*BishopValueMidgame+Value(325);
- static const Value EndgameLimit = 4*RookValueMidgame-Value(325);
- Value npm = this->non_pawn_material(WHITE) + this->non_pawn_material(BLACK);
-
- if(npm >= MidgameLimit)
- return PHASE_MIDGAME;
+ Value npm = non_pawn_material(WHITE) + non_pawn_material(BLACK);
+
+ if (npm >= MidgameLimit)
+ return PHASE_MIDGAME;
else if(npm <= EndgameLimit)
- return PHASE_ENDGAME;
+ return PHASE_ENDGAME;
else
- return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
+ return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
+}
+
+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)
+ && relative_rank(c, move_to(m)) > RANK_4;
}
inline bool Position::move_is_pawn_push_to_7th(Move m) const {
- Color c = this->side_to_move();
- return
- this->piece_on(move_from(m)) == pawn_of_color(c) &&
- pawn_rank(c, move_to(m)) == RANK_7;
+
+ Color c = side_to_move();
+ return piece_on(move_from(m)) == pawn_of_color(c)
+ && relative_rank(c, move_to(m)) == RANK_7;
}
inline bool Position::move_is_passed_pawn_push(Move m) const {
- Color c = this->side_to_move();
- return
- this->piece_on(move_from(m)) == pawn_of_color(c) &&
- this->pawn_is_passed(c, move_to(m));
+
+ Color c = side_to_move();
+ return piece_on(move_from(m)) == pawn_of_color(c)
+ && pawn_is_passed(c, move_to(m));
}
-
+
inline bool Position::move_was_passed_pawn_push(Move m) const {
- Color c = opposite_color(this->side_to_move());
- return
- this->piece_on(move_to(m)) == pawn_of_color(c) &&
- this->pawn_is_passed(c, move_to(m));
+
+ Color c = opposite_color(side_to_move());
+ return piece_on(move_to(m)) == pawn_of_color(c)
+ && pawn_is_passed(c, move_to(m));
}
inline int Position::rule_50_counter() const {
+
return rule50;
}
inline bool Position::opposite_colored_bishops() const {
- return
- this->bishop_count(WHITE) == 1 && this->bishop_count(BLACK) == 1 &&
- square_color(this->bishop_list(WHITE, 0)) !=
- square_color(this->bishop_list(BLACK, 0));
+
+ 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));
}
inline bool Position::has_pawn_on_7th(Color c) const {
- return this->pawns(c) & relative_rank_bb(c, RANK_7);
+
+ return pawns(c) & relative_rank_bb(c, RANK_7);
}
-
+
#endif // !defined(POSITION_H_INCLUDED)