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/>.
38 //// Local definitions
44 AMBIGUITY_NONE, AMBIGUITY_FILE, AMBIGUITY_RANK, AMBIGUITY_BOTH
47 Ambiguity move_ambiguity(const Position& pos, Move m);
48 const string time_string(int milliseconds);
49 const string score_string(Value v);
57 /// move_to_uci() converts a move to a string in coordinate notation
58 /// (g1f3, a7a8q, etc.). The only special case is castling moves, where we
59 /// print in the e1g1 notation in normal chess mode, and in e1h1 notation in
62 const std::string move_to_uci(Move m, bool chess960) {
64 std::string promotion;
65 Square from = move_from(m);
66 Square to = move_to(m);
74 if (move_is_short_castle(m) && !chess960)
75 return from == SQ_E1 ? "e1g1" : "e8g8";
77 if (move_is_long_castle(m) && !chess960)
78 return from == SQ_E1 ? "e1c1" : "e8c8";
80 if (move_is_promotion(m))
81 promotion = char(tolower(piece_type_to_char(move_promotion_piece(m))));
83 return square_to_string(from) + square_to_string(to) + promotion;
87 /// move_from_uci() takes a position and a string representing a move in
88 /// simple coordinate notation and returns an equivalent Move.
90 Move move_from_uci(const Position& pos, const std::string& str) {
92 MoveStack mlist[MOVES_MAX];
93 MoveStack* last = generate<MV_LEGAL>(pos, mlist);
95 for (MoveStack* cur = mlist; cur != last; cur++)
96 if (str == move_to_uci(cur->move, pos.is_chess960()))
103 /// move_to_san() takes a position and a move as input, where it is assumed
104 /// that the move is a legal move from the position. The return value is
105 /// a string containing the move in short algebraic notation.
107 const string move_to_san(Position& pos, Move m) {
110 assert(move_is_ok(m));
113 Square from = move_from(m);
114 Square to = move_to(m);
115 PieceType pt = type_of_piece(pos.piece_on(from));
123 if (move_is_long_castle(m))
125 else if (move_is_short_castle(m))
131 san += piece_type_to_char(pt);
133 switch (move_ambiguity(pos, m)) {
137 san += file_to_char(square_file(from));
140 san += rank_to_char(square_rank(from));
143 san += square_to_string(from);
150 if (pos.move_is_capture(m))
153 san += file_to_char(square_file(from));
157 san += square_to_string(to);
159 if (move_is_promotion(m))
162 san += piece_type_to_char(move_promotion_piece(m));
166 // The move gives check ? We don't use pos.move_is_check() here
167 // because we need to test for mate after the move is done.
171 san += pos.is_mate() ? "#" : "+";
178 /// pretty_pv() creates a human-readable string from a position and a PV.
179 /// It is used to write search information to the log file (which is created
180 /// when the UCI parameter "Use Search Log" is "true").
182 const string pretty_pv(Position& pos, int time, int depth,
183 Value score, ValueType type, Move pv[]) {
185 const int64_t K = 1000;
186 const int64_t M = 1000000;
187 const int startColumn = 29;
188 const size_t maxLength = 80 - startColumn;
189 const string lf = string("\n") + string(startColumn, ' ');
191 StateInfo state[PLY_MAX_PLUS_2], *st = state;
197 // First print depth, score, time and searched nodes...
198 s << std::setw(2) << depth
199 << (type == VALUE_TYPE_LOWER ? " >" : type == VALUE_TYPE_UPPER ? " <" : " ")
200 << std::setw(7) << score_string(score)
201 << std::setw(8) << time_string(time);
203 if (pos.nodes_searched() < M)
204 s << std::setw(8) << pos.nodes_searched() / 1 << " ";
205 else if (pos.nodes_searched() < K * M)
206 s << std::setw(7) << pos.nodes_searched() / K << " K ";
208 s << std::setw(7) << pos.nodes_searched() / M << " M ";
210 // ...then print the full PV line in short algebraic notation
211 while (*m != MOVE_NONE)
213 san = move_to_san(pos, *m);
214 length += san.length() + 1;
216 if (length > maxLength)
218 length = san.length() + 1;
223 pos.do_move(*m++, *st++);
226 // Restore original position before to leave
227 while (m != pv) pos.undo_move(*--m);
235 Ambiguity move_ambiguity(const Position& pos, Move m) {
237 MoveStack mlist[MOVES_MAX], *last;
239 Square from = move_from(m);
240 Square to = move_to(m);
241 Piece pc = pos.piece_on(from);
242 int matches = 0, f = 0, r = 0;
244 // If there is only one piece 'pc' then move cannot be ambiguous
245 if (pos.piece_count(pos.side_to_move(), type_of_piece(pc)) == 1)
246 return AMBIGUITY_NONE;
248 // Collect all legal moves of piece 'pc' with destination 'to'
249 last = generate<MV_LEGAL>(pos, mlist);
250 for (MoveStack* cur = mlist; cur != last; cur++)
251 if (move_to(cur->move) == to && pos.piece_on(move_from(cur->move)) == pc)
252 candidates[matches++] = cur->move;
255 return AMBIGUITY_NONE;
257 for (int i = 0; i < matches; i++)
259 if (square_file(move_from(candidates[i])) == square_file(from))
262 if (square_rank(move_from(candidates[i])) == square_rank(from))
266 return f == 1 ? AMBIGUITY_FILE : r == 1 ? AMBIGUITY_RANK : AMBIGUITY_BOTH;
270 const string time_string(int millisecs) {
272 const int MSecMinute = 1000 * 60;
273 const int MSecHour = 1000 * 60 * 60;
276 s << std::setfill('0');
278 int hours = millisecs / MSecHour;
279 int minutes = (millisecs - hours * MSecHour) / MSecMinute;
280 int seconds = (millisecs - hours * MSecHour - minutes * MSecMinute) / 1000;
285 s << std::setw(2) << minutes << ':' << std::setw(2) << seconds;
290 const string score_string(Value v) {
294 if (v >= VALUE_MATE - 200)
295 s << "#" << (VALUE_MATE - v + 1) / 2;
296 else if (v <= -VALUE_MATE + 200)
297 s << "-#" << (VALUE_MATE + v) / 2;
300 float floatScore = float(v) / float(PawnValueMidgame);
304 s << std::setprecision(2) << std::fixed << floatScore;