/// penalty for a king, looking at the king file and the two closest files.
template<Color Us>
-Value Entry::evaluate_shelter(const Position& pos, Square ksq) {
+void Entry::evaluate_shelter(const Position& pos, Square ksq, Score& shelter) {
constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
Bitboard ourPawns = b & pos.pieces(Us);
Bitboard theirPawns = b & pos.pieces(Them);
- Value safety = (shift<Down>(theirPawns) & BlockSquares & ksq) ? Value(374) : Value(5);
+ Value bonus[] = { (shift<Down>(theirPawns) & BlockSquares & ksq) ? Value(374) : Value(5),
+ VALUE_ZERO };
File center = clamp(file_of(ksq), FILE_B, FILE_G);
for (File f = File(center - 1); f <= File(center + 1); ++f)
Rank theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
int d = std::min(f, ~f);
- safety += ShelterStrength[d][ourRank];
- safety -= (ourRank && (ourRank == theirRank - 1)) ? 66 * (theirRank == RANK_3)
- : UnblockedStorm[d][theirRank];
+ bonus[MG] += ShelterStrength[d][ourRank];
+
+ if (ourRank && (ourRank == theirRank - 1))
+ bonus[MG] -= 82 * (theirRank == RANK_3), bonus[EG] -= 82 * (theirRank == RANK_3);
+ else
+ bonus[MG] -= UnblockedStorm[d][theirRank];
}
- return safety;
+ if (bonus[MG] > mg_value(shelter))
+ shelter = make_score(bonus[MG], bonus[EG]);
}
else while (pawns)
minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(&pawns)));
- Value bonus = evaluate_shelter<Us>(pos, ksq);
+ Score shelter = make_score(-VALUE_INFINITE, VALUE_ZERO);
+ evaluate_shelter<Us>(pos, ksq, shelter);
// If we can castle use the bonus after the castling if it is bigger
if (pos.can_castle(Us | KING_SIDE))
- bonus = std::max(bonus, evaluate_shelter<Us>(pos, relative_square(Us, SQ_G1)));
+ evaluate_shelter<Us>(pos, relative_square(Us, SQ_G1), shelter);
if (pos.can_castle(Us | QUEEN_SIDE))
- bonus = std::max(bonus, evaluate_shelter<Us>(pos, relative_square(Us, SQ_C1)));
+ evaluate_shelter<Us>(pos, relative_square(Us, SQ_C1), shelter);
- return make_score(bonus, -16 * minPawnDist);
+ return shelter - make_score(VALUE_ZERO, 16 * minPawnDist);
}
// Explicit template instantiation