-// Struct Eval::Info contains various information computed and collected
-// by the evaluation functions.
-struct Info {
-
- // Pointers to material and pawn hash table entries
- Material::Entry* mi;
- Pawns::Entry* pi;
-
- // attackedBy[color][piece type] is a bitboard representing all squares
- // attacked by a given color and piece type, attackedBy[color][ALL_PIECES]
- // contains all squares attacked by the given color.
- Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
-
- // kingRing[color] is the zone around the king which is considered
- // by the king safety evaluation. This consists of the squares directly
- // adjacent to the king, and the three (or two, for a king on an edge file)
- // squares two ranks in front of the king. For instance, if black's king
- // is on g8, kingRing[BLACK] is a bitboard containing the squares f8, h8,
- // f7, g7, h7, f6, g6 and h6.
- Bitboard kingRing[COLOR_NB];
-
- // kingAttackersCount[color] is the number of pieces of the given color
- // which attack a square in the kingRing of the enemy king.
- int kingAttackersCount[COLOR_NB];
-
- // kingAttackersWeight[color] is the sum of the "weight" of the pieces of the
- // given color which attack a square in the kingRing of the enemy king. The
- // weights of the individual piece types are given by the variables
- // QueenAttackWeight, RookAttackWeight, BishopAttackWeight and
- // KnightAttackWeight in evaluate.cpp
- int kingAttackersWeight[COLOR_NB];
-
- // kingAdjacentZoneAttacksCount[color] is the number of attacks to squares
- // directly adjacent to the king of the given color. Pieces which attack
- // more than one square are counted multiple times. For instance, if black's
- // king is on g8 and there's a white knight on g5, this knight adds
- // 2 to kingAdjacentZoneAttacksCount[BLACK].
- int kingAdjacentZoneAttacksCount[COLOR_NB];
-};
-
-extern void init();
-extern Value evaluate(const Position& pos, Value& margin, Info* ei);
-extern std::string trace(const Position& pos);