X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.h;h=4713094d537ea0f89b3ac44bc7cd3fe7e0f2ac21;hp=6c48b54c341676f98a58243a7f42869e2a69e74b;hb=673bc5526fa3d352f823ad144fb521b5dc98f45c;hpb=a21a110188eed1ff41f2a1535a93b48c654663de diff --git a/src/position.h b/src/position.h index 6c48b54c..4713094d 100644 --- a/src/position.h +++ b/src/position.h @@ -1,7 +1,7 @@ /* Stockfish, a UCI chess playing engine derived from Glaurung 2.1 Copyright (C) 2004-2008 Tord Romstad (Glaurung author) - Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad + Copyright (C) 2008-2012 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 @@ -23,43 +23,22 @@ #include #include "bitboard.h" -#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; +/// The checkInfo struct is initialized at c'tor time and keeps info used +/// to detect if a move gives check. class Position; - -/// struct checkInfo is initialized at c'tor time and keeps -/// info used to detect if a move gives check. +class Thread; struct CheckInfo { - explicit CheckInfo(const Position&); - - Bitboard dcCandidates; - 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 -}; + explicit CheckInfo(const Position&); -/// Game phase -enum Phase { - PHASE_ENDGAME = 0, - PHASE_MIDGAME = 128 + Bitboard dcCandidates; + Bitboard pinned; + Bitboard checkSq[8]; + Square ksq; }; @@ -70,14 +49,14 @@ enum Phase { struct StateInfo { Key pawnKey, materialKey; - int castleRights, rule50, gamePly, pliesFromNull; - Square epSquare; - Score value; Value npMaterial[2]; + int castleRights, rule50, pliesFromNull; + Score psqScore; + Square epSquare; - PieceType capturedType; Key key; Bitboard checkersBB; + PieceType capturedType; StateInfo* previous; }; @@ -106,77 +85,48 @@ struct StateInfo { class Position { - Position(); // No default or copy c'tor allowed - Position(const Position& pos); + // No copy c'tor or assignment operator allowed + 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); + Position() {} + Position(const Position& p, Thread* t) { copy(p, t); } + Position(const std::string& f, bool c960, Thread* t) { from_fen(f, c960, t); } // Text input/output - void from_fen(const std::string& fen, bool isChess960); + void copy(const Position& pos, Thread* th); + void from_fen(const std::string& fen, bool isChess960, Thread* th); 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; - - // Bitboard representation of the position - Bitboard empty_squares() const; - Bitboard occupied_squares() const; - Bitboard pieces_of_color(Color c) const; + // Position representation + Bitboard pieces() 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; Bitboard pieces(PieceType pt1, PieceType pt2, 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 + Piece piece_on(Square s) const; Square king_square(Color c) const; + Square ep_square() const; + bool square_empty(Square s) const; + const Square* piece_list(Color c, PieceType pt) const; + int piece_count(Color c, PieceType pt) const; - // Castling rights - bool can_castle_kingside(Color c) const; - bool can_castle_queenside(Color c) const; + // Castling + 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; + bool castle_impeded(CastleRight f) 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; - - // Checking pieces and under check information - Bitboard checkers() const; + // Checking bool in_check() const; + Bitboard checkers() const; + Bitboard discovered_check_candidates() const; + Bitboard pinned_pieces() const; - // Piece lists - Square piece_list(Color c, PieceType pt, int index) const; - const Square* piece_list_begin(Color c, PieceType pt) const; - - // Information about attacks to or from a given square + // Attacks to/from a given square Bitboard attackers_to(Square s) const; Bitboard attackers_to(Square s, Bitboard occ) const; Bitboard attacks_from(Piece p, Square s) const; @@ -185,91 +135,69 @@ public: template 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; - - // Piece captured with previous moves + 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 piece_moved(Move m) const; PieceType captured_piece_type() const; - // Information about pawns + // Piece specific bool pawn_is_passed(Color c, Square s) const; - - // Weak squares - bool square_is_weak(Square s, Color c) const; + bool pawn_on_7th(Color c) const; + bool opposite_bishops() const; + bool bishop_pair(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); - void do_null_move(StateInfo& st); - void undo_null_move(); + template void do_null_move(StateInfo& st); // Static exchange evaluation int see(Move m) const; int see_sign(Move m) const; - static int see_value(PieceType pt); // Accessing hash keys - Key get_key() const; - Key get_exclusion_key() const; - Key get_pawn_key() const; - Key get_material_key() const; - - // Incremental evaluation - Score value() const; + Key key() const; + Key exclusion_key() const; + Key pawn_key() const; + Key material_key() const; + + // Incremental piece-square evaluation + Score psq_score() const; + Score psq_delta(Piece p, Square from, Square to) const; Value non_pawn_material(Color c) const; - static Score pst_delta(Piece piece, Square from, Square to); - - // Game termination checks - bool is_mate() const; - template bool is_draw() const; - - // Number of plies from starting position - int startpos_ply_counter() const; // Other properties of the position - bool opposite_colored_bishops() const; - bool has_pawn_on_7th(Color c) const; + Color side_to_move() const; + int startpos_ply_counter() const; bool is_chess960() const; - - // Current thread ID searching on the position - int thread() const; - + Thread& this_thread() const; int64_t nodes_searched() const; void set_nodes_searched(int64_t n); + template bool is_draw() const; // Position consistency check, for debugging - bool is_ok(int* failedStep = NULL) const; + bool pos_is_ok(int* failedStep = NULL) const; + void flip(); - // 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) + // Initialization helpers (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; - - // 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(); + void set_castle_right(Color c, Square rfrom); + bool move_is_legal(const Move m) const; - template - Bitboard hidden_checkers(Color c) const; + // Helper template functions + template void do_castle_move(Move m); + template Bitboard hidden_checkers() const; // Computing hash keys from scratch (for initialization and debugging) Key compute_key() const; @@ -277,45 +205,36 @@ private: Key compute_material_key() const; // Computing incremental evaluation scores and material counts - static Score pst(Color c, PieceType pt, Square s); - Score compute_value() const; + Score compute_psq_score() const; Value compute_non_pawn_material(Color c) const; - // Board - Piece board[64]; - - // Bitboards - Bitboard byTypeBB[8], byColorBB[2]; - - // Piece counts - int pieceCount[2][8]; // [color][pieceType] - - // Piece lists - Square pieceList[2][8][16]; // [color][pieceType][index] - int index[64]; // [square] + // Board and pieces + Piece board[64]; // [square] + Bitboard byTypeBB[8]; // [pieceType] + Bitboard byColorBB[2]; // [color] + int pieceCount[2][8]; // [color][pieceType] + 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] + Bitboard castlePath[16]; // [castleRight] StateInfo startState; - File initialKFile, initialKRFile, initialQRFile; - bool chess960; - int startPosPlyCounter; - int threadID; int64_t nodes; + int startPosPly; + Color sideToMove; + Thread* thisThread; 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[8]; // [file] + 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 { @@ -330,43 +249,23 @@ 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 Piece Position::piece_moved(Move m) const { + return board[from_sq(m)]; } -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)]; +inline bool Position::square_empty(Square s) const { + return board[s] == NO_PIECE; } inline Color Position::side_to_move() const { return sideToMove; } -inline Bitboard Position::occupied_squares() const { - return byTypeBB[0]; +inline Bitboard Position::pieces() const { + return byTypeBB[ALL_PIECES]; } -inline Bitboard Position::empty_squares() const { - return ~occupied_squares(); -} - -inline Bitboard Position::pieces_of_color(Color c) const { +inline Bitboard Position::pieces(Color c) const { return byColorBB[c]; } @@ -390,11 +289,7 @@ 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]; } @@ -406,24 +301,28 @@ 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(CastleRight f) const { + return st->castleRights & f; } -inline bool Position::can_castle_queenside(Color side) const { - return st->castleRights & (4+4*int(side)); +inline bool Position::can_castle(Color c) const { + return st->castleRights & ((WHITE_OO | WHITE_OOO) << c); } -inline bool Position::can_castle(Color side) const { - return can_castle_kingside(side) || can_castle_queenside(side); +inline bool Position::castle_impeded(CastleRight f) const { + return byTypeBB[ALL_PIECES] & castlePath[f]; } -inline Square Position::initial_kr_square(Color c) const { - return relative_square(c, make_square(initialKRFile, RANK_1)); +inline Square Position::castle_rook_square(CastleRight f) const { + return castleRookSquare[f]; } -inline Square Position::initial_qr_square(Color c) const { - return relative_square(c, make_square(initialQRFile, RANK_1)); +template +inline Bitboard Position::attacks_from(Square s) const { + + return Pt == BISHOP || Pt == ROOK ? attacks_bb(s, pieces()) + : Pt == QUEEN ? attacks_from(s) | attacks_from(s) + : StepAttacksBB[Pt][s]; } template<> @@ -431,24 +330,12 @@ inline Bitboard Position::attacks_from(Square s, Color c) const { return StepAttacksBB[make_piece(c, PAWN)][s]; } -template // Knight and King and white pawns -inline Bitboard Position::attacks_from(Square s) const { - return StepAttacksBB[Piece][s]; -} - -template<> -inline Bitboard Position::attacks_from(Square s) const { - return bishop_attacks_bb(s, occupied_squares()); +inline Bitboard Position::attacks_from(Piece p, Square s) const { + return attacks_from(p, s, byTypeBB[ALL_PIECES]); } -template<> -inline Bitboard Position::attacks_from(Square s) const { - return rook_attacks_bb(s, occupied_squares()); -} - -template<> -inline Bitboard Position::attacks_from(Square s) const { - return attacks_from(s) | attacks_from(s); +inline Bitboard Position::attackers_to(Square s) const { + return attackers_to(s, byTypeBB[ALL_PIECES]); } inline Bitboard Position::checkers() const { @@ -456,71 +343,73 @@ inline Bitboard Position::checkers() const { } 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 Bitboard Position::discovered_check_candidates() const { + return hidden_checkers(); } -inline bool Position::square_is_weak(Square s, Color c) const { - return !(pieces(PAWN, opposite_color(c)) & attack_span_mask(c, s)); +inline Bitboard Position::pinned_pieces() const { + return hidden_checkers(); } -inline int Position::see_value(PieceType pt) { - return seeValues[pt]; +inline bool Position::pawn_is_passed(Color c, Square s) const { + return !(pieces(PAWN, ~c) & passed_pawn_mask(c, s)); } -inline Key Position::get_key() const { +inline Key Position::key() const { return st->key; } -inline Key Position::get_exclusion_key() const { +inline Key Position::exclusion_key() const { return st->key ^ zobExclusion; } -inline Key Position::get_pawn_key() const { +inline Key Position::pawn_key() const { return st->pawnKey; } -inline Key Position::get_material_key() const { +inline Key Position::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::psq_delta(Piece p, Square from, Square to) const { + return pieceSquareTable[p][to] - pieceSquareTable[p][from]; } -inline Score Position::pst_delta(Piece piece, Square from, Square to) { - return PieceSquareTable[piece][to] - PieceSquareTable[piece][from]; -} - -inline Score Position::value() const { - return st->value; +inline Score Position::psq_score() const { + return st->psqScore; } 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 type_of(piece_moved(m)) == PAWN + && pawn_is_passed(sideToMove, to_sq(m)); } inline int Position::startpos_ply_counter() const { - return startPosPlyCounter; + return startPosPly + st->pliesFromNull; // HACK +} + +inline bool Position::opposite_bishops() const { + + return pieceCount[WHITE][BISHOP] == 1 + && pieceCount[BLACK][BISHOP] == 1 + && opposite_colors(pieceList[WHITE][BISHOP][0], pieceList[BLACK][BISHOP][0]); } -inline bool Position::opposite_colored_bishops() const { +inline bool Position::bishop_pair(Color c) 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[c][BISHOP] >= 2 + && opposite_colors(pieceList[c][BISHOP][0], pieceList[c][BISHOP][1]); } -inline bool Position::has_pawn_on_7th(Color c) const { +inline bool Position::pawn_on_7th(Color c) const { return pieces(PAWN, c) & rank_bb(relative_rank(c, RANK_7)); } @@ -528,26 +417,25 @@ 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_empty(to_sq(m)); } -inline PieceType Position::captured_piece_type() const { - return st->capturedType; -} +inline bool Position::is_capture(Move m) const { -inline int Position::thread() const { - return threadID; + // Note that castle is coded as "king captures the rook" + assert(is_ok(m)); + return (!square_empty(to_sq(m)) && !is_castle(m)) || is_enpassant(m); } -inline void Position::do_allow_oo(Color c) { - st->castleRights |= (1 + int(c)); +inline PieceType Position::captured_piece_type() const { + return st->capturedType; } -inline void Position::do_allow_ooo(Color c) { - st->castleRights |= (4 + 4*int(c)); +inline Thread& Position::this_thread() const { + return *thisThread; } #endif // !defined(POSITION_H_INCLUDED)