2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2012 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/>.
31 static const char* PieceToChar = " PNBRQK pnbrqk";
34 /// score_to_uci() converts a value to a string suitable for use with the UCI
35 /// protocol specifications:
37 /// cp <x> The score from the engine's point of view in centipawns.
38 /// mate <y> Mate in y moves, not plies. If the engine is getting mated
39 /// use negative values for y.
41 string score_to_uci(Value v, Value alpha, Value beta) {
45 if (abs(v) < VALUE_MATE_IN_MAX_PLY)
46 s << "cp " << v * 100 / int(PawnValueMg);
48 s << "mate " << (v > 0 ? VALUE_MATE - v + 1 : -VALUE_MATE - v) / 2;
50 s << (v >= beta ? " lowerbound" : v <= alpha ? " upperbound" : "");
56 /// move_to_uci() converts a move to a string in coordinate notation
57 /// (g1f3, a7a8q, etc.). The only special case is castling moves, where we print
58 /// in the e1g1 notation in normal chess mode, and in e1h1 notation in chess960
59 /// mode. Internally castle moves are always coded as "king captures rook".
61 const string move_to_uci(Move m, bool chess960) {
63 Square from = from_sq(m);
72 if (type_of(m) == CASTLE && !chess960)
73 to = (to > from ? FILE_G : FILE_C) | rank_of(from);
75 string move = square_to_string(from) + square_to_string(to);
77 if (type_of(m) == PROMOTION)
78 move += PieceToChar[make_piece(BLACK, promotion_type(m))]; // Lower case
84 /// move_from_uci() takes a position and a string representing a move in
85 /// simple coordinate notation and returns an equivalent legal Move if any.
87 Move move_from_uci(const Position& pos, string& str) {
89 if (str.length() == 5) // Junior could send promotion piece in uppercase
90 str[4] = char(tolower(str[4]));
92 for (MoveList<LEGAL> ml(pos); !ml.end(); ++ml)
93 if (str == move_to_uci(ml.move(), pos.is_chess960()))
100 /// move_to_san() takes a position and a legal Move as input and returns its
101 /// short algebraic notation representation.
103 const string move_to_san(Position& pos, Move m) {
111 assert(pos.move_is_legal(m));
114 bool ambiguousMove, ambiguousFile, ambiguousRank;
116 Color us = pos.side_to_move();
117 Square from = from_sq(m);
118 Square to = to_sq(m);
119 Piece pc = pos.piece_on(from);
120 PieceType pt = type_of(pc);
122 if (type_of(m) == CASTLE)
123 san = to > from ? "O-O" : "O-O-O";
128 san = PieceToChar[pt]; // Upper case
130 // Disambiguation if we have more then one piece with destination 'to'
131 // note that for pawns is not needed because starting file is explicit.
132 ambiguousMove = ambiguousFile = ambiguousRank = false;
134 attackers = (pos.attacks_from(pc, to) & pos.pieces(us, pt)) ^ from;
138 Square sq = pop_lsb(&attackers);
140 // Pinned pieces are not included in the possible sub-set
141 if (!pos.pl_move_is_legal(make_move(sq, to), pos.pinned_pieces()))
144 ambiguousFile |= file_of(sq) == file_of(from);
145 ambiguousRank |= rank_of(sq) == rank_of(from);
146 ambiguousMove = true;
152 san += file_to_char(file_of(from));
154 else if (!ambiguousRank)
155 san += rank_to_char(rank_of(from));
158 san += square_to_string(from);
161 else if (pos.is_capture(m))
162 san = file_to_char(file_of(from));
164 if (pos.is_capture(m))
167 san += square_to_string(to);
169 if (type_of(m) == PROMOTION)
170 san += string("=") + PieceToChar[promotion_type(m)];
173 if (pos.move_gives_check(m, CheckInfo(pos)))
177 san += MoveList<LEGAL>(pos).size() ? "+" : "#";
185 /// pretty_pv() formats human-readable search information, typically to be
186 /// appended to the search log file. It uses the two helpers below to pretty
187 /// format time and score respectively.
189 static string time_to_string(int millisecs) {
191 const int MSecMinute = 1000 * 60;
192 const int MSecHour = 1000 * 60 * 60;
194 int hours = millisecs / MSecHour;
195 int minutes = (millisecs % MSecHour) / MSecMinute;
196 int seconds = ((millisecs % MSecHour) % MSecMinute) / 1000;
203 s << setfill('0') << setw(2) << minutes << ':' << setw(2) << seconds;
208 static string score_to_string(Value v) {
212 if (v >= VALUE_MATE_IN_MAX_PLY)
213 s << "#" << (VALUE_MATE - v + 1) / 2;
215 else if (v <= VALUE_MATED_IN_MAX_PLY)
216 s << "-#" << (VALUE_MATE + v) / 2;
219 s << setprecision(2) << fixed << showpos << float(v) / PawnValueMg;
224 string pretty_pv(Position& pos, int depth, Value value, int time, Move pv[]) {
226 const int64_t K = 1000;
227 const int64_t M = 1000000;
229 StateInfo state[MAX_PLY_PLUS_2], *st = state;
235 s << setw(2) << depth
236 << setw(8) << score_to_string(value)
237 << setw(8) << time_to_string(time);
239 if (pos.nodes_searched() < M)
240 s << setw(8) << pos.nodes_searched() / 1 << " ";
242 else if (pos.nodes_searched() < K * M)
243 s << setw(7) << pos.nodes_searched() / K << "K ";
246 s << setw(7) << pos.nodes_searched() / M << "M ";
248 padding = string(s.str().length(), ' ');
249 length = padding.length();
251 while (*m != MOVE_NONE)
253 san = move_to_san(pos, *m);
255 if (length + san.length() > 80)
258 length = padding.length();
262 length += san.length() + 1;
264 pos.do_move(*m++, *st++);