2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
6 Stockfish is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 Stockfish is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>.
33 const string time_string(int milliseconds);
34 const string score_string(Value v);
38 /// move_to_uci() converts a move to a string in coordinate notation
39 /// (g1f3, a7a8q, etc.). The only special case is castling moves, where we
40 /// print in the e1g1 notation in normal chess mode, and in e1h1 notation in
43 const string move_to_uci(Move m, bool chess960) {
45 Square from = move_from(m);
46 Square to = move_to(m);
55 if (move_is_short_castle(m) && !chess960)
56 return from == SQ_E1 ? "e1g1" : "e8g8";
58 if (move_is_long_castle(m) && !chess960)
59 return from == SQ_E1 ? "e1c1" : "e8c8";
61 if (move_is_promotion(m))
62 promotion = char(tolower(piece_type_to_char(promotion_piece_type(m))));
64 return square_to_string(from) + square_to_string(to) + promotion;
68 /// move_from_uci() takes a position and a string representing a move in
69 /// simple coordinate notation and returns an equivalent Move if any.
70 /// Moves are guaranteed to be legal.
72 Move move_from_uci(const Position& pos, const string& str) {
74 MoveStack mlist[MAX_MOVES];
75 MoveStack* last = generate<MV_LEGAL>(pos, mlist);
77 for (MoveStack* cur = mlist; cur != last; cur++)
78 if (str == move_to_uci(cur->move, pos.is_chess960()))
85 /// move_to_san() takes a position and a move as input, where it is assumed
86 /// that the move is a legal move from the position. The return value is
87 /// a string containing the move in short algebraic notation.
89 const string move_to_san(Position& pos, Move m) {
92 assert(move_is_ok(m));
95 bool ambiguousMove, ambiguousFile, ambiguousRank;
96 Square sq, from = move_from(m);
97 Square to = move_to(m);
98 PieceType pt = piece_type(pos.piece_on(from));
107 if (move_is_long_castle(m))
109 else if (move_is_short_castle(m))
115 san = piece_type_to_char(pt);
117 // Disambiguation if we have more then one piece with destination 'to'
118 // note that for pawns is not needed because starting file is explicit.
119 attackers = pos.attackers_to(to) & pos.pieces(pt, pos.side_to_move());
120 clear_bit(&attackers, from);
121 ambiguousMove = ambiguousFile = ambiguousRank = false;
125 sq = pop_1st_bit(&attackers);
127 if (square_file(sq) == square_file(from))
128 ambiguousFile = true;
130 if (square_rank(sq) == square_rank(from))
131 ambiguousRank = true;
133 ambiguousMove = true;
139 san += file_to_char(square_file(from));
140 else if (!ambiguousRank)
141 san += rank_to_char(square_rank(from));
143 san += square_to_string(from);
147 if (pos.move_is_capture(m))
150 san += file_to_char(square_file(from));
155 san += square_to_string(to);
157 if (move_is_promotion(m))
160 san += piece_type_to_char(promotion_piece_type(m));
164 // The move gives check? We don't use pos.move_gives_check() here
165 // because we need to test for a mate after the move is done.
169 san += pos.is_mate() ? "#" : "+";
176 /// pretty_pv() creates a human-readable string from a position and a PV.
177 /// It is used to write search information to the log file (which is created
178 /// when the UCI parameter "Use Search Log" is "true").
180 const string pretty_pv(Position& pos, int depth, Value score, int time, Move pv[]) {
182 const int64_t K = 1000;
183 const int64_t M = 1000000;
184 const int startColumn = 28;
185 const size_t maxLength = 80 - startColumn;
186 const string lf = string("\n") + string(startColumn, ' ');
188 StateInfo state[PLY_MAX_PLUS_2], *st = state;
194 // First print depth, score, time and searched nodes...
195 s << std::setw(2) << depth
196 << std::setw(8) << score_string(score)
197 << std::setw(8) << time_string(time);
199 if (pos.nodes_searched() < M)
200 s << std::setw(8) << pos.nodes_searched() / 1 << " ";
201 else if (pos.nodes_searched() < K * M)
202 s << std::setw(7) << pos.nodes_searched() / K << "K ";
204 s << std::setw(7) << pos.nodes_searched() / M << "M ";
206 // ...then print the full PV line in short algebraic notation
207 while (*m != MOVE_NONE)
209 san = move_to_san(pos, *m);
210 length += san.length() + 1;
212 if (length > maxLength)
214 length = san.length() + 1;
219 pos.do_move(*m++, *st++);
222 // Restore original position before to leave
223 while (m != pv) pos.undo_move(*--m);
231 const string time_string(int millisecs) {
233 const int MSecMinute = 1000 * 60;
234 const int MSecHour = 1000 * 60 * 60;
236 int hours = millisecs / MSecHour;
237 int minutes = (millisecs % MSecHour) / MSecMinute;
238 int seconds = ((millisecs % MSecHour) % MSecMinute) / 1000;
245 s << std::setfill('0') << std::setw(2) << minutes << ':' << std::setw(2) << seconds;
250 const string score_string(Value v) {
254 if (v >= VALUE_MATE - 200)
255 s << "#" << (VALUE_MATE - v + 1) / 2;
256 else if (v <= -VALUE_MATE + 200)
257 s << "-#" << (VALUE_MATE + v) / 2;
259 s << std::setprecision(2) << std::fixed << std::showpos << float(v) / PawnValueMidgame;