X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fposition.h;h=3624e29e723738b63c40b894a70adcb0f622f276;hb=9f8058bd26df1c3ca37b85f811026f1eb82e6524;hp=b526bfe7e6e39c039f0b95d93f365b651057492c;hpb=c6630abe0d6f229af7d6ae788643a0e8fa1737f7;p=stockfish diff --git a/src/position.h b/src/position.h index b526bfe7..3624e29e 100644 --- a/src/position.h +++ b/src/position.h @@ -1,7 +1,6 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 - Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008 Marco Costalba + Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file) Stockfish is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -17,705 +16,411 @@ along with this program. If not, see . */ - -#if !defined(POSITION_H_INCLUDED) +#ifndef POSITION_H_INCLUDED #define POSITION_H_INCLUDED -// Disable a silly and noisy warning from MSVC compiler -#if defined(_MSC_VER) +#include +#include +#include // For std::unique_ptr +#include -// Forcing value to bool 'true' or 'false' (performance warning) -#pragma warning(disable: 4800) +#include "bitboard.h" +#include "evaluate.h" +#include "psqt.h" +#include "types.h" -#endif +#include "nnue/nnue_accumulator.h" -//// -//// Includes -//// -#include "bitboard.h" -#include "color.h" -#include "direction.h" -#include "move.h" -#include "piece.h" -#include "phase.h" -#include "square.h" -#include "value.h" - - -//// -//// Constants -//// - -/// FEN string for the initial position: -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 -/// maximum search depth is 100, and during position setup we reset the -/// move counter for every non-reversible move): -const int MaxGameLength = 220; - - -//// -//// Types -//// - -/// Castle rights, encoded as bit fields: - -enum CastleRights { - NO_CASTLES = 0, - WHITE_OO = 1, - BLACK_OO = 2, - WHITE_OOO = 4, - BLACK_OOO = 8, - ALL_CASTLES = 15 -}; +/// StateInfo struct stores information needed 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), a StateInfo object must be passed. +struct StateInfo { -/// 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. - -struct UndoInfo { - int castleRights; + // Copied when making a move + Key pawnKey; + Key materialKey; + Value nonPawnMaterial[COLOR_NB]; + int castlingRights; + int rule50; + int pliesFromNull; Square epSquare; - Bitboard checkersBB, pinners[2], pinned[2], dcCandidates[2]; - Key key, pawnKey, materialKey; - int rule50; - Move lastMove; - Value mgValue, egValue; - PieceType capture; + + // Not copied when making a move (will be recomputed anyhow) + Key key; + Bitboard checkersBB; + Piece capturedPiece; + StateInfo* previous; + Bitboard blockersForKing[COLOR_NB]; + Bitboard pinners[COLOR_NB]; + Bitboard checkSquares[PIECE_TYPE_NB]; + int repetition; + + // Used by NNUE + Eval::NNUE::Accumulator accumulator; + DirtyPiece dirtyPiece; }; -/// 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 -/// pieces of that color. -/// * A bitboard of all occupied squares. -/// * A bitboard of all checking pieces. -/// * A 64-entry array of pieces, indexed by the squares of the board. -/// * The current side to move. -/// * Information about the castling rights for both sides. -/// * The initial files of the kings and both pairs of rooks. This is -/// used to implement the Chess960 castling rules. -/// * The en passant square (which is SQ_NONE if no en passant capture is -/// possible). -/// * The squares of the kings for both sides. -/// * The last move played. -/// * Hash keys for the position itself, the current pawn structure, and -/// the current material situation. -/// * Hash keys for all previous positions in the game (for detecting -/// repetition draws. -/// * A counter for detecting 50 move rule draws. +/// A list to keep track of the position states along the setup moves (from the +/// start position to the position just before the search starts). Needed by +/// 'draw by repetition' detection. Use a std::deque because pointers to +/// elements are not invalidated upon list resizing. +typedef std::unique_ptr> StateListPtr; -class Position { - friend class MaterialInfo; - friend class EndgameFunctions; +/// Position class stores information regarding the board representation as +/// pieces, side to move, hash keys, castling info, etc. Important methods are +/// do_move() and undo_move(), used by the search to update node info when +/// traversing the search tree. +class Thread; +class Position { public: - // Constructors - Position() {}; - Position(const Position& pos); - Position(const std::string& fen); - - // Text input/output - void from_fen(const std::string& fen); - const std::string to_fen() const; - 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 + static void init(); + + Position() = default; + Position(const Position&) = delete; + Position& operator=(const Position&) = delete; + + // FEN string input/output + Position& set(const std::string& fenStr, bool isChess960, StateInfo* si, Thread* th); + Position& set(const std::string& code, Color c, StateInfo* si); + const std::string fen() const; + + // Position representation + Bitboard pieces(PieceType pt) const; + Bitboard pieces(PieceType pt1, PieceType pt2) const; + Bitboard pieces(Color c) const; + Bitboard pieces(Color c, PieceType pt) const; + Bitboard pieces(Color c, PieceType pt1, PieceType pt2) const; 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; - - // Bitboard representation of the position - Bitboard empty_squares() const; - Bitboard occupied_squares() const; - Bitboard pieces_of_color(Color c) const; - Bitboard pieces_of_type(PieceType pt) const; - Bitboard pieces_of_color_and_type(Color c, PieceType pt) const; - Bitboard pawns() const; - Bitboard knights() const; - Bitboard bishops() const; - Bitboard rooks() const; - Bitboard queens() const; - Bitboard kings() const; - Bitboard rooks_and_queens() const; - Bitboard bishops_and_queens() const; - Bitboard sliders() const; - Bitboard pawns(Color c) const; - Bitboard knights(Color c) const; - Bitboard bishops(Color c) const; - Bitboard rooks(Color c) const; - Bitboard queens(Color c) const; - Bitboard kings(Color c) const; - Bitboard rooks_and_queens(Color c) const; - Bitboard bishops_and_queens(Color c) const; - Bitboard sliders_of_color(Color c) const; - - // Number of pieces of each color and type - int piece_count(Color c, PieceType pt) const; - - // The en passant square Square ep_square() const; - - // Current king position for each color - 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(Color c) const; - Square initial_kr_square(Color c) const; - Square initial_qr_square(Color c) const; - - // Attack bitboards - Bitboard sliding_attacks(Square s, Direction d) const; - Bitboard ray_attacks(Square s, SignedDirection d) const; - Bitboard pawn_attacks(Color c, Square s) const; - - template - Bitboard piece_attacks(Square s) const; - - // 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 + bool empty(Square s) const; + template int count(Color c) const; + template int count() const; + template Square square(Color c) const; + bool is_on_semiopen_file(Color c, Square s) const; + + // Castling + CastlingRights castling_rights(Color c) const; + bool can_castle(CastlingRights cr) const; + bool castling_impeded(CastlingRights cr) const; + Square castling_rook_square(CastlingRights cr) const; + + // Checking Bitboard checkers() const; + Bitboard blockers_for_king(Color c) const; + Bitboard check_squares(PieceType pt) const; + Bitboard pinners(Color c) const; + bool is_discovered_check_on_king(Color c, Move m) const; - // Piece lists - Square piece_list(Color c, PieceType pt, 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 pawn_attacks_square(Color c, Square f, Square t) const; - - template - Bitboard piece_attacks_square(Square f, Square t) const; // Dispatch at compile-time - - bool piece_attacks_square(Piece p, Square f, Square t) const; // Dispatch at run-time + // Attacks to/from a given square + Bitboard attackers_to(Square s) const; + Bitboard attackers_to(Square s, Bitboard occupied) const; + Bitboard slider_blockers(Bitboard sliders, Square s, Bitboard& pinners) const; // Properties of moves - bool pl_move_is_legal(Move m) const; - bool move_is_check(Move m) 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; - bool move_attacks_square(Move m, Square s) const; - - // Information about pawns - bool pawn_is_passed(Color c, Square s) const; - bool pawn_is_isolated(Color c, Square s) const; - bool pawn_is_doubled(Color c, Square s) const; - - // Open and half-open files - bool file_is_open(File f) const; - bool file_is_half_open(Color c, File f) const; - - // Weak squares - bool square_is_weak(Square s, Color c) const; + bool legal(Move m) const; + bool pseudo_legal(const Move m) const; + bool capture(Move m) const; + bool capture_or_promotion(Move m) const; + bool gives_check(Move m) const; + bool advanced_pawn_push(Move m) const; + Piece moved_piece(Move m) const; + Piece captured_piece() const; + + // Piece specific + bool pawn_passed(Color c, Square s) const; + bool opposite_bishops() const; + int pawns_on_same_color_squares(Color c, Square s) 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); - - // 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; - Key get_pawn_key() const; - Key get_material_key() const; + void do_move(Move m, StateInfo& newSt); + void do_move(Move m, StateInfo& newSt, bool givesCheck); + void undo_move(Move m); + void do_null_move(StateInfo& newSt); + void undo_null_move(); - // Incremental evaluation - Value mg_value() const; - Value eg_value() const; - Value non_pawn_material(Color c) const; - Phase game_phase() const; - Value mg_pst_delta(Move m) const; + // Static Exchange Evaluation + bool see_ge(Move m, Value threshold = VALUE_ZERO) const; - // Game termination checks - bool is_mate() const; - bool is_draw() const; - - // Check if one side threatens a mate in one - bool has_mate_threat(Color c); - - // Number of plies since the last non-reversible move - int rule_50_counter() const; + // Accessing hash keys + Key key() const; + Key key_after(Move m) const; + Key material_key() const; + Key pawn_key() const; // Other properties of the position - bool opposite_colored_bishops() const; - bool has_pawn_on_7th(Color c) const; - - // Reset the gamePly variable to 0 - void reset_game_ply(); + Color side_to_move() const; + int game_ply() const; + bool is_chess960() const; + Thread* this_thread() const; + bool is_draw(int ply) const; + bool has_game_cycle(int ply) const; + bool has_repeated() const; + int rule50_count() const; + Score psq_score() const; + Value non_pawn_material(Color c) const; + Value non_pawn_material() const; // Position consistency check, for debugging - bool is_ok(int* failedStep = NULL) const; + bool pos_is_ok() const; + void flip(); - // Static member functions: - static void init_zobrist(); - static void init_piece_square_tables(); + // Used by NNUE + StateInfo* state() const; private: - // Initialization helper functions (used while setting up a position) - void clear(); - void put_piece(Piece p, Square s); - void allow_oo(Color c); - 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_castle_move(Move m); - void undo_promotion_move(Move m, const UndoInfo &u); - void undo_ep_move(Move m); - void find_checkers(); - - template - void update_checkers(Bitboard* pCheckersBB, Square ksq, Square from, Square to, Bitboard dcCandidates); - - template - Bitboard hidden_checks(Color c, Square ksq, Bitboard& pinners) const; - - // Computing hash keys from scratch (for initialization and debugging) - Key compute_key() const; - Key compute_pawn_key() const; - 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; - Value compute_non_pawn_material(Color c) const; - - // Bitboards - Bitboard byColorBB[2], byTypeBB[8]; - Bitboard checkersBB; - mutable Bitboard pinners[2], pinned[2], dcCandidates[2]; - - // 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 + // Initialization helpers (used while setting up a position) + void set_castling_right(Color c, Square rfrom); + void set_state(StateInfo* si) const; + void set_check_info(StateInfo* si) const; + + // Other helpers + void put_piece(Piece pc, Square s); + void remove_piece(Square s); + void move_piece(Square from, Square to); + template + void do_castling(Color us, Square from, Square& to, Square& rfrom, Square& rto); + + // Data members + Piece board[SQUARE_NB]; + Bitboard byTypeBB[PIECE_TYPE_NB]; + Bitboard byColorBB[COLOR_NB]; + int pieceCount[PIECE_NB]; + int castlingRightsMask[SQUARE_NB]; + Square castlingRookSquare[CASTLING_RIGHT_NB]; + Bitboard castlingPath[CASTLING_RIGHT_NB]; + int gamePly; 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; - Value npMaterial[2]; - - // 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]; + Score psq; + Thread* thisThread; + StateInfo* st; + bool chess960; }; - -//// -//// Inline functions -//// - -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) == EMPTY; -} - -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 piece_value_midgame(piece_on(s)); -} - -inline Value Position::endgame_value_of_piece_on(Square s) const { - return piece_value_endgame(piece_on(s)); -} +extern std::ostream& operator<<(std::ostream& os, const Position& pos); inline Color Position::side_to_move() const { return sideToMove; } -inline Bitboard Position::occupied_squares() const { - return byTypeBB[0]; +inline Piece Position::piece_on(Square s) const { + assert(is_ok(s)); + return board[s]; } -inline Bitboard Position::empty_squares() const { - return ~(occupied_squares()); +inline bool Position::empty(Square s) const { + return piece_on(s) == NO_PIECE; } -inline Bitboard Position::pieces_of_color(Color c) const { - return byColorBB[c]; +inline Piece Position::moved_piece(Move m) const { + return piece_on(from_sq(m)); } -inline Bitboard Position::pieces_of_type(PieceType pt) const { +inline Bitboard Position::pieces(PieceType pt = ALL_PIECES) const { return byTypeBB[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::pieces(PieceType pt1, PieceType pt2) const { + return pieces(pt1) | pieces(pt2); } -inline Bitboard Position::pawns() const { - return pieces_of_type(PAWN); -} - -inline Bitboard Position::knights() const { - return pieces_of_type(KNIGHT); -} - -inline Bitboard Position::bishops() const { - return pieces_of_type(BISHOP); -} - -inline Bitboard Position::rooks() const { - return pieces_of_type(ROOK); -} - -inline Bitboard Position::queens() const { - return pieces_of_type(QUEEN); -} - -inline Bitboard Position::kings() const { - return pieces_of_type(KING); -} - -inline Bitboard Position::rooks_and_queens() const { - return rooks() | queens(); -} - -inline Bitboard Position::bishops_and_queens() const { - return bishops() | queens(); -} - -inline Bitboard Position::sliders() const { - return bishops() | queens() | rooks(); -} - -inline Bitboard Position::pawns(Color c) const { - return pieces_of_color_and_type(c, PAWN); -} - -inline Bitboard Position::knights(Color c) const { - return pieces_of_color_and_type(c, KNIGHT); -} - -inline Bitboard Position::bishops(Color c) const { - return pieces_of_color_and_type(c, BISHOP); -} - -inline Bitboard Position::rooks(Color c) const { - return pieces_of_color_and_type(c, ROOK); -} - -inline Bitboard Position::queens(Color c) const { - return pieces_of_color_and_type(c, QUEEN); -} - -inline Bitboard Position::kings(Color c) const { - return pieces_of_color_and_type(c, KING); +inline Bitboard Position::pieces(Color c) const { + return byColorBB[c]; } -inline Bitboard Position::rooks_and_queens(Color c) const { - return rooks_and_queens() & pieces_of_color(c); +inline Bitboard Position::pieces(Color c, PieceType pt) const { + return pieces(c) & pieces(pt); } -inline Bitboard Position::bishops_and_queens(Color c) const { - return bishops_and_queens() & pieces_of_color(c); +inline Bitboard Position::pieces(Color c, PieceType pt1, PieceType pt2) const { + return pieces(c) & (pieces(pt1) | pieces(pt2)); } -inline Bitboard Position::sliders_of_color(Color c) const { - return sliders() & pieces_of_color(c); +template inline int Position::count(Color c) const { + return pieceCount[make_piece(c, Pt)]; } -inline int Position::piece_count(Color c, PieceType pt) const { - return pieceCount[c][pt]; +template inline int Position::count() const { + return count(WHITE) + count(BLACK); } -inline Square Position::piece_list(Color c, PieceType pt, int index) const { - return pieceList[c][pt][index]; +template inline Square Position::square(Color c) const { + assert(count(c) == 1); + return lsb(pieces(c, Pt)); } inline Square Position::ep_square() const { - return epSquare; -} - -inline Square Position::king_square(Color c) const { - return kingSquare[c]; -} - -inline bool Position::can_castle_kingside(Color side) const { - return castleRights & (1+int(side)); -} - -inline bool Position::can_castle_queenside(Color side) const { - return castleRights & (4+4*int(side)); -} - -inline bool Position::can_castle(Color side) const { - return can_castle_kingside(side) || can_castle_queenside(side); + return st->epSquare; } -inline Square Position::initial_kr_square(Color c) const { - return relative_square(c, make_square(initialKRFile, RANK_1)); +inline bool Position::is_on_semiopen_file(Color c, Square s) const { + return !(pieces(c, PAWN) & file_bb(s)); } -inline Square Position::initial_qr_square(Color c) const { - return relative_square(c, make_square(initialQRFile, RANK_1)); +inline bool Position::can_castle(CastlingRights cr) const { + return st->castlingRights & cr; } -inline Bitboard Position::pawn_attacks(Color c, Square s) const { - return StepAttackBB[piece_of_color_and_type(c, PAWN)][s]; +inline CastlingRights Position::castling_rights(Color c) const { + return c & CastlingRights(st->castlingRights); } -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[piece_of_color_and_type(opposite_color(sideToMove), PAWN)][s]; -} - -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[KNIGHT][s]; -} +inline bool Position::castling_impeded(CastlingRights cr) const { + assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO); -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return bishop_attacks_bb(s, occupied_squares()); + return pieces() & castlingPath[cr]; } -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return rook_attacks_bb(s, occupied_squares()); -} +inline Square Position::castling_rook_square(CastlingRights cr) const { + assert(cr == WHITE_OO || cr == WHITE_OOO || cr == BLACK_OO || cr == BLACK_OOO); -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return piece_attacks(s) | piece_attacks(s); + return castlingRookSquare[cr]; } -template<> -inline Bitboard Position::piece_attacks(Square s) const { - return StepAttackBB[KING][s]; +inline Bitboard Position::attackers_to(Square s) const { + return attackers_to(s, pieces()); } inline Bitboard Position::checkers() const { - return checkersBB; + return st->checkersBB; } -inline bool Position::is_check() const { - return checkersBB != EmptyBoardBB; +inline Bitboard Position::blockers_for_king(Color c) const { + return st->blockersForKing[c]; } -inline bool Position::pawn_attacks_square(Color c, Square f, Square t) const { - return bit_is_set(pawn_attacks(c, f), t); +inline Bitboard Position::pinners(Color c) const { + return st->pinners[c]; } -template -Bitboard Position::piece_attacks_square(Square f, Square t) const { - return bit_is_set(piece_attacks(f), t); +inline Bitboard Position::check_squares(PieceType pt) const { + return st->checkSquares[pt]; } -inline Bitboard Position::attacks_to(Square s, Color c) const { - - return attacks_to(s) & pieces_of_color(c); +inline bool Position::is_discovered_check_on_king(Color c, Move m) const { + return st->blockersForKing[c] & from_sq(m); } -inline bool Position::square_is_attacked(Square s, Color c) const { - - return attacks_to(s, c) != EmptyBoardBB; +inline bool Position::pawn_passed(Color c, Square s) const { + return !(pieces(~c, PAWN) & passed_pawn_span(c, s)); } -inline bool Position::pawn_is_passed(Color c, Square s) const { - return !(pawns(opposite_color(c)) & passed_pawn_mask(c, s)); +inline bool Position::advanced_pawn_push(Move m) const { + return type_of(moved_piece(m)) == PAWN + && relative_rank(sideToMove, to_sq(m)) > RANK_5; } -inline bool Position::pawn_is_isolated(Color c, Square s) const { - return !(pawns(c) & neighboring_files_bb(s)); +inline int Position::pawns_on_same_color_squares(Color c, Square s) const { + return popcount(pieces(c, PAWN) & ((DarkSquares & s) ? DarkSquares : ~DarkSquares)); } -inline bool Position::pawn_is_doubled(Color c, Square s) const { - return pawns(c) & squares_behind(c, s); +inline Key Position::key() const { + return st->rule50 < 14 ? st->key + : st->key ^ make_key((st->rule50 - 14) / 8); } -inline bool Position::file_is_open(File f) const { - return !(pawns() & file_bb(f)); +inline Key Position::pawn_key() const { + return st->pawnKey; } -inline bool Position::file_is_half_open(Color c, File f) const { - return !(pawns(c) & file_bb(f)); +inline Key Position::material_key() const { + return st->materialKey; } -inline bool Position::square_is_weak(Square s, Color c) const { - return !(pawns(c) & outpost_mask(opposite_color(c), s)); +inline Score Position::psq_score() const { + return psq; } -inline Key Position::get_key() const { - return key; -} - -inline Key Position::get_pawn_key() const { - return pawnKey; +inline Value Position::non_pawn_material(Color c) const { + return st->nonPawnMaterial[c]; } -inline Key Position::get_material_key() const { - return materialKey; +inline Value Position::non_pawn_material() const { + return non_pawn_material(WHITE) + non_pawn_material(BLACK); } -inline Value Position::mg_pst(Color c, PieceType pt, Square s) const { - return MgPieceSquareTable[piece_of_color_and_type(c, pt)][s]; +inline int Position::game_ply() const { + return gamePly; } -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 int Position::rule50_count() const { + return st->rule50; } -inline Value Position::eg_pst(Color c, PieceType pt, Square s) const { - return EgPieceSquareTable[piece_of_color_and_type(c, pt)][s]; +inline bool Position::opposite_bishops() const { + return count(WHITE) == 1 + && count(BLACK) == 1 + && opposite_colors(square(WHITE), square(BLACK)); } -inline Value Position::mg_value() const { - return mgValue; +inline bool Position::is_chess960() const { + return chess960; } -inline Value Position::eg_value() const { - return egValue; +inline bool Position::capture_or_promotion(Move m) const { + assert(is_ok(m)); + return type_of(m) != NORMAL ? type_of(m) != CASTLING : !empty(to_sq(m)); } -inline Value Position::non_pawn_material(Color c) const { - return npMaterial[c]; +inline bool Position::capture(Move m) const { + assert(is_ok(m)); + // Castling is encoded as "king captures rook" + return (!empty(to_sq(m)) && type_of(m) != CASTLING) || type_of(m) == EN_PASSANT; } -inline Phase Position::game_phase() const { - - // 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); - - 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 Piece Position::captured_piece() const { + return st->capturedPiece; } -inline bool Position::move_is_deep_pawn_push(Move m) const { - - Color c = side_to_move(); - 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)) == piece_of_color_and_type(c, PAWN) - && relative_rank(c, move_to(m)) == RANK_7; +inline Thread* Position::this_thread() const { + return thisThread; } -inline bool Position::move_is_passed_pawn_push(Move m) const { +inline void Position::put_piece(Piece pc, Square s) { - Color c = side_to_move(); - return piece_on(move_from(m)) == piece_of_color_and_type(c, PAWN) - && pawn_is_passed(c, move_to(m)); + board[s] = pc; + byTypeBB[ALL_PIECES] |= byTypeBB[type_of(pc)] |= s; + byColorBB[color_of(pc)] |= s; + pieceCount[pc]++; + pieceCount[make_piece(color_of(pc), ALL_PIECES)]++; + psq += PSQT::psq[pc][s]; } -inline bool Position::move_was_passed_pawn_push(Move m) const { +inline void Position::remove_piece(Square s) { - Color c = opposite_color(side_to_move()); - return piece_on(move_to(m)) == piece_of_color_and_type(c, PAWN) - && pawn_is_passed(c, move_to(m)); + Piece pc = board[s]; + byTypeBB[ALL_PIECES] ^= s; + byTypeBB[type_of(pc)] ^= s; + byColorBB[color_of(pc)] ^= s; + /* board[s] = NO_PIECE; Not needed, overwritten by the capturing one */ + pieceCount[pc]--; + pieceCount[make_piece(color_of(pc), ALL_PIECES)]--; + psq -= PSQT::psq[pc][s]; } -inline int Position::rule_50_counter() const { +inline void Position::move_piece(Square from, Square to) { - return rule50; + Piece pc = board[from]; + Bitboard fromTo = from | to; + byTypeBB[ALL_PIECES] ^= fromTo; + byTypeBB[type_of(pc)] ^= fromTo; + byColorBB[color_of(pc)] ^= fromTo; + board[from] = NO_PIECE; + board[to] = pc; + psq += PSQT::psq[pc][to] - PSQT::psq[pc][from]; } -inline bool Position::opposite_colored_bishops() const { - - 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 void Position::do_move(Move m, StateInfo& newSt) { + do_move(m, newSt, gives_check(m)); } -inline bool Position::has_pawn_on_7th(Color c) const { +inline StateInfo* Position::state() const { - return pawns(c) & relative_rank_bb(c, RANK_7); + return st; } - -#endif // !defined(POSITION_H_INCLUDED) +#endif // #ifndef POSITION_H_INCLUDED