2 Stockfish, a UCI chess playing engine derived from Glaurung 2.1
3 Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
4 Copyright (C) 2008-2013 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/>.
20 #ifndef PAWNS_H_INCLUDED
21 #define PAWNS_H_INCLUDED
29 /// Pawns::Entry contains various information about a pawn structure. Currently,
30 /// it only includes a middle game and end game pawn structure evaluation, and a
31 /// bitboard of passed pawns. We may want to add further information in the future.
32 /// A lookup to the pawn hash table (performed by calling the probe function)
33 /// returns a pointer to an Entry object.
37 Score pawns_value() const { return value; }
38 Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; }
39 Bitboard passed_pawns(Color c) const { return passedPawns[c]; }
40 int pawns_on_same_color_squares(Color c, Square s) const { return pawnsOnSquares[c][!!(DarkSquares & s)]; }
41 int semiopen(Color c, File f) const { return semiopenFiles[c] & (1 << int(f)); }
42 int semiopen_on_side(Color c, File f, bool left) const {
44 return semiopenFiles[c] & (left ? ((1 << int(f)) - 1) : ~((1 << int(f+1)) - 1));
48 Score king_safety(const Position& pos, Square ksq) {
50 return kingSquares[Us] == ksq && castleRights[Us] == pos.can_castle(Us)
51 ? kingSafety[Us] : update_safety<Us>(pos, ksq);
55 Score update_safety(const Position& pos, Square ksq);
58 Value shelter_storm(const Position& pos, Square ksq);
61 Bitboard passedPawns[COLOR_NB];
62 Bitboard pawnAttacks[COLOR_NB];
63 Square kingSquares[COLOR_NB];
64 int minKPdistance[COLOR_NB];
65 int castleRights[COLOR_NB];
67 int semiopenFiles[COLOR_NB];
68 Score kingSafety[COLOR_NB];
69 int pawnsOnSquares[COLOR_NB][COLOR_NB];
72 typedef HashTable<Entry, 16384> Table;
74 Entry* probe(const Position& pos, Table& entries);
78 #endif // #ifndef PAWNS_H_INCLUDED