2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2009 Marco Costalba
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/>.
21 #if !defined MOVEPICK_H_INCLUDED
22 #define MOVEPICK_H_INCLUDED
41 PH_TT_MOVES, // Transposition table move and mate killer
42 PH_GOOD_CAPTURES, // Queen promotions and captures with SEE values >= 0
43 PH_KILLERS, // Killer moves from the current ply
44 PH_NONCAPTURES, // Non-captures and underpromotions
45 PH_BAD_CAPTURES, // Queen promotions and captures with SEE values < 0
46 PH_EVASIONS, // Check evasions
47 PH_QCAPTURES, // Captures in quiescence search
48 PH_QCHECKS, // Non-capture checks in quiescence search
52 typedef uint8_t MovegenPhaseT;
54 /// MovePicker is a class which is used to pick one legal move at a time from
55 /// the current position. It is initialized with a Position object and a few
56 /// moves we have reason to believe are good. The most important method is
57 /// MovePicker::pick_next_move(), which returns a new legal move each time it
58 /// is called, until there are no legal moves left, when MOVE_NONE is returned.
59 /// In order to improve the efficiency of the alpha beta algorithm, MovePicker
60 /// attempts to return the moves which are most likely to be strongest first.
64 MovePicker& operator=(const MovePicker&); // silence a warning under MSVC
67 MovePicker(const Position& p, Move ttm, Depth d, const History& h, SearchStack* ss = NULL);
69 Move get_next_move(Lock& lock);
70 int number_of_moves() const;
71 Bitboard discovered_check_candidates() const;
74 void score_captures();
75 void score_noncaptures();
76 void score_evasions();
77 Move pick_move_from_list();
81 Move ttMoves[2], killers[2];
82 const MovegenPhaseT* phasePtr;
83 int movesPicked, numOfMoves, numOfBadCaptures;
86 MoveStack moves[256], badCaptures[64];
94 /// MovePicker::number_of_moves() simply returns the numOfMoves member
95 /// variable. It is intended to be used in positions where the side to move
96 /// is in check, for detecting checkmates or situations where there is only
97 /// a single reply to check.
99 inline int MovePicker::number_of_moves() const {
103 /// MovePicker::discovered_check_candidates() returns a bitboard containing
104 /// all pieces which can possibly give discovered check. This bitboard is
105 /// computed by the constructor function.
107 inline Bitboard MovePicker::discovered_check_candidates() const {
111 #endif // !defined(MOVEPICK_H_INCLUDED)