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/>.
37 //// Local definitions
43 AMBIGUITY_NONE, AMBIGUITY_FILE, AMBIGUITY_RANK, AMBIGUITY_BOTH
46 Ambiguity move_ambiguity(const Position& pos, Move m);
47 const string time_string(int milliseconds);
48 const string score_string(Value v);
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
58 /// print in the e1g1 notation in normal chess mode, and in e1h1 notation in
61 const std::string move_to_uci(Move m, bool chess960) {
63 std::string promotion;
64 Square from = move_from(m);
65 Square to = move_to(m);
73 if (move_is_short_castle(m) && !chess960)
74 return from == SQ_E1 ? "e1g1" : "e8g8";
76 if (move_is_long_castle(m) && !chess960)
77 return from == SQ_E1 ? "e1c1" : "e8c8";
79 if (move_is_promotion(m))
80 promotion = char(tolower(piece_type_to_char(move_promotion_piece(m))));
82 return square_to_string(from) + square_to_string(to) + promotion;
86 /// move_from_uci() takes a position and a string representing a move in
87 /// simple coordinate notation and returns an equivalent Move.
89 Move move_from_uci(const Position& pos, const std::string& str) {
91 MoveStack mlist[MOVES_MAX];
92 MoveStack* last = generate<MV_LEGAL>(pos, mlist);
94 for (MoveStack* cur = mlist; cur != last; cur++)
95 if (str == move_to_uci(cur->move, pos.is_chess960()))
102 /// move_to_san() takes a position and a move as input, where it is assumed
103 /// that the move is a legal move from the position. The return value is
104 /// a string containing the move in short algebraic notation.
106 const string move_to_san(Position& pos, Move m) {
109 assert(move_is_ok(m));
112 Square from = move_from(m);
113 Square to = move_to(m);
114 PieceType pt = type_of_piece(pos.piece_on(from));
122 if (move_is_long_castle(m))
124 else if (move_is_short_castle(m))
130 san += piece_type_to_char(pt);
132 switch (move_ambiguity(pos, m)) {
136 san += file_to_char(square_file(from));
139 san += rank_to_char(square_rank(from));
142 san += square_to_string(from);
149 if (pos.move_is_capture(m))
152 san += file_to_char(square_file(from));
156 san += square_to_string(to);
158 if (move_is_promotion(m))
161 san += piece_type_to_char(move_promotion_piece(m));
165 // The move gives check ? We don't use pos.move_is_check() here
166 // because we need to test for mate after the move is done.
170 san += pos.is_mate() ? "#" : "+";
177 /// pretty_pv() creates a human-readable string from a position and a PV.
178 /// It is used to write search information to the log file (which is created
179 /// when the UCI parameter "Use Search Log" is "true").
181 const string pretty_pv(const Position& pos, int time, int depth,
182 Value score, ValueType type, Move pv[]) {
184 const int64_t K = 1000;
185 const int64_t M = 1000000;
186 const int startColumn = 29;
187 const size_t maxLength = 80 - startColumn;
188 const string lf = string("\n") + string(startColumn, ' ');
195 Position p(pos, pos.thread());
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 for (Move* m = pv; *m != MOVE_NONE; m++)
213 san = move_to_san(p, *m);
214 length += san.length() + 1;
216 if (length > maxLength)
218 length = san.length() + 1;
232 Ambiguity move_ambiguity(const Position& pos, Move m) {
234 MoveStack mlist[MOVES_MAX], *last;
236 Square from = move_from(m);
237 Square to = move_to(m);
238 Piece pc = pos.piece_on(from);
239 int matches = 0, f = 0, r = 0;
241 // If there is only one piece 'pc' then move cannot be ambiguous
242 if (pos.piece_count(pos.side_to_move(), type_of_piece(pc)) == 1)
243 return AMBIGUITY_NONE;
245 // Collect all legal moves of piece 'pc' with destination 'to'
246 last = generate<MV_LEGAL>(pos, mlist);
247 for (MoveStack* cur = mlist; cur != last; cur++)
248 if (move_to(cur->move) == to && pos.piece_on(move_from(cur->move)) == pc)
249 candidates[matches++] = cur->move;
252 return AMBIGUITY_NONE;
254 for (int i = 0; i < matches; i++)
256 if (square_file(move_from(candidates[i])) == square_file(from))
259 if (square_rank(move_from(candidates[i])) == square_rank(from))
263 return f == 1 ? AMBIGUITY_FILE : r == 1 ? AMBIGUITY_RANK : AMBIGUITY_BOTH;
267 const string time_string(int millisecs) {
269 const int MSecMinute = 1000 * 60;
270 const int MSecHour = 1000 * 60 * 60;
273 s << std::setfill('0');
275 int hours = millisecs / MSecHour;
276 int minutes = (millisecs - hours * MSecHour) / MSecMinute;
277 int seconds = (millisecs - hours * MSecHour - minutes * MSecMinute) / 1000;
282 s << std::setw(2) << minutes << ':' << std::setw(2) << seconds;
287 const string score_string(Value v) {
291 if (v >= VALUE_MATE - 200)
292 s << "#" << (VALUE_MATE - v + 1) / 2;
293 else if (v <= -VALUE_MATE + 200)
294 s << "-#" << (VALUE_MATE + v) / 2;
297 float floatScore = float(v) / float(PawnValueMidgame);
301 s << std::setprecision(2) << std::fixed << floatScore;