/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2013 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include "position.h"
#include "types.h"
-const int PawnTableSize = 16384;
+namespace Pawns {
-/// PawnEntry is a class which contains various information about a pawn
-/// structure. Currently, it only includes a middle game and an end game
-/// pawn structure evaluation, and a bitboard of passed pawns. We may want
-/// to add further information in the future. A lookup to the pawn hash
-/// table (performed by calling the probe method in a PawnTable object)
-/// returns a pointer to a PawnEntry object.
+/// Pawns::Entry contains various information about a pawn structure. Currently,
+/// it only includes a middle game and end game pawn structure evaluation, and a
+/// bitboard of passed pawns. We may want to add further information in the future.
+/// A lookup to the pawn hash table (performed by calling the probe function)
+/// returns a pointer to an Entry object.
-class PawnEntry {
+struct Entry {
- friend struct PawnTable;
-
-public:
- Score pawns_value() const;
- Bitboard pawn_attacks(Color c) const;
- Bitboard passed_pawns(Color c) const;
- int file_is_half_open(Color c, File f) const;
- int has_open_file_to_left(Color c, File f) const;
- int has_open_file_to_right(Color c, File f) const;
+ Score pawns_value() const { return value; }
+ Bitboard pawn_attacks(Color c) const { return pawnAttacks[c]; }
+ Bitboard passed_pawns(Color c) const { return passedPawns[c]; }
+ int file_is_half_open(Color c, File f) const { return halfOpenFiles[c] & (1 << int(f)); }
+ int has_open_file_to_left(Color c, File f) const { return halfOpenFiles[c] & ((1 << int(f)) - 1); }
+ int has_open_file_to_right(Color c, File f) const { return halfOpenFiles[c] & ~((1 << int(f+1)) - 1); }
+ int pawns_on_same_color_squares(Color c, Square s) const { return pawnsOnSquares[c][!!(BlackSquares & s)]; }
template<Color Us>
- Score king_safety(const Position& pos, Square ksq);
+ Score king_safety(const Position& pos, Square ksq) {
+
+ return kingSquares[Us] == ksq && castleRights[Us] == pos.can_castle(Us)
+ ? kingSafety[Us] : update_safety<Us>(pos, ksq);
+ }
-private:
template<Color Us>
Score update_safety(const Position& pos, Square ksq);
Value shelter_storm(const Position& pos, Square ksq);
Key key;
- Bitboard passedPawns[2];
- Bitboard pawnAttacks[2];
- Square kingSquares[2];
- int minKPdistance[2];
- int castleRights[2];
+ Bitboard passedPawns[COLOR_NB];
+ Bitboard pawnAttacks[COLOR_NB];
+ Square kingSquares[COLOR_NB];
+ int minKPdistance[COLOR_NB];
+ int castleRights[COLOR_NB];
Score value;
- int halfOpenFiles[2];
- Score kingSafety[2];
+ int halfOpenFiles[COLOR_NB];
+ Score kingSafety[COLOR_NB];
+ int pawnsOnSquares[COLOR_NB][COLOR_NB];
};
+typedef HashTable<Entry, 16384> Table;
-/// The PawnTable class represents a pawn hash table. The most important
-/// method is probe, which returns a pointer to a PawnEntry object.
-
-struct PawnTable {
-
- PawnEntry* probe(const Position& pos);
-
- template<Color Us>
- static Score evaluate_pawns(const Position& pos, Bitboard ourPawns,
- Bitboard theirPawns, PawnEntry* e);
-
- HashTable<PawnEntry, PawnTableSize> entries;
-};
-
-
-inline Score PawnEntry::pawns_value() const {
- return value;
-}
-
-inline Bitboard PawnEntry::pawn_attacks(Color c) const {
- return pawnAttacks[c];
-}
-
-inline Bitboard PawnEntry::passed_pawns(Color c) const {
- return passedPawns[c];
-}
-
-inline int PawnEntry::file_is_half_open(Color c, File f) const {
- return halfOpenFiles[c] & (1 << int(f));
-}
-
-inline int PawnEntry::has_open_file_to_left(Color c, File f) const {
- return halfOpenFiles[c] & ((1 << int(f)) - 1);
-}
-
-inline int PawnEntry::has_open_file_to_right(Color c, File f) const {
- return halfOpenFiles[c] & ~((1 << int(f+1)) - 1);
-}
+Entry* probe(const Position& pos, Table& entries);
-template<Color Us>
-inline Score PawnEntry::king_safety(const Position& pos, Square ksq) {
- return kingSquares[Us] == ksq && castleRights[Us] == pos.can_castle(Us)
- ? kingSafety[Us] : update_safety<Us>(pos, ksq);
}
#endif // !defined(PAWNS_H_INCLUDED)