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 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(PAWNS_H_INCLUDED)
22 #define PAWNS_H_INCLUDED
35 /// PawnInfo is a class which contains various information about a pawn
36 /// structure. Currently, it only includes a middle game and an end game
37 /// pawn structure evaluation, and a bitboard of passed pawns. We may want
38 /// to add further information in the future. A lookup to the pawn hash table
39 /// (performed by calling the get_pawn_info method in a PawnInfoTable object)
40 /// returns a pointer to a PawnInfo object.
44 friend class PawnInfoTable;
47 Value mg_value() const;
48 Value eg_value() const;
49 Value kingside_storm_value(Color c) const;
50 Value queenside_storm_value(Color c) const;
51 Bitboard passed_pawns() const;
52 bool file_is_half_open(Color c, File f) const;
53 bool has_open_file_to_left(Color c, File f) const;
54 bool has_open_file_to_right(Color c, File f) const;
61 int16_t mgValue, egValue;
62 int8_t ksStormValue[2], qsStormValue[2];
63 uint8_t halfOpenFiles[2];
67 /// The PawnInfoTable class represents a pawn hash table. It is basically
68 /// just an array of PawnInfo objects and a few methods for accessing these
69 /// objects. The most important method is get_pawn_info, which looks up a
70 /// position in the table and returns a pointer to a PawnInfo object.
75 PawnInfoTable(unsigned numOfEntries);
78 PawnInfo *get_pawn_info(const Position &pos);
90 inline Value PawnInfo::mg_value() const {
91 return Value(mgValue);
94 inline Value PawnInfo::eg_value() const {
95 return Value(egValue);
98 inline Bitboard PawnInfo::passed_pawns() const {
102 inline Value PawnInfo::kingside_storm_value(Color c) const {
103 return Value(ksStormValue[c]);
106 inline Value PawnInfo::queenside_storm_value(Color c) const {
107 return Value(qsStormValue[c]);
110 inline bool PawnInfo::file_is_half_open(Color c, File f) const {
111 return (halfOpenFiles[c] & (1 << int(f)));
114 inline bool PawnInfo::has_open_file_to_left(Color c, File f) const {
115 return halfOpenFiles[c] & ((1 << int(f)) - 1);
118 inline bool PawnInfo::has_open_file_to_right(Color c, File f) const {
119 return halfOpenFiles[c] & ~((1 << int(f+1)) - 1);
122 inline void PawnInfo::clear() {
125 memset(this, 0, sizeof(PawnInfo));
127 halfOpenFiles[WHITE] = halfOpenFiles[BLACK] = 0xFF;
131 #endif // !defined(PAWNS_H_INCLUDED)