/*
- Glaurung, a UCI chess playing engine.
- Copyright (C) 2004-2008 Tord Romstad
+ Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+ Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
+ Copyright (C) 2008 Marco Costalba
- Glaurung is free software: you can redistribute it and/or modify
+ Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
-
- Glaurung is distributed in the hope that it will be useful,
+
+ Stockfish is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
-
+
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
class Position;
+/// A move needs 17 bits to be stored
+///
+/// bit 0- 5: destination square (from 0 to 63)
+/// bit 6-11: origin square (from 0 to 63)
+/// bit 12-14: promotion piece type
+/// bit 15: en passant flag
+/// bit 16: castle flag
+///
+/// Special cases are MOVE_NONE and MOVE_NULL. We can sneak these in
+/// because in any normal move destination square is always different
+/// from origin square while MOVE_NONE and MOVE_NULL have the same
+/// origin and destination square, 0 and 1 respectively.
+
enum Move {
MOVE_NONE = 0,
- MOVE_NULL = 65,
- MOVE_MAX = 0xFFFFFF
+ MOVE_NULL = 65
};
////
inline Square move_from(Move m) {
- return Square((int(m) >> 6) & 077);
+ return Square((int(m) >> 6) & 0x3F);
}
inline Square move_to(Move m) {
- return Square(m & 077);
+ return Square(m & 0x3F);
}
inline PieceType move_promotion(Move m) {