#define V Value
#define S(mg, eg) make_score(mg, eg)
- // Isolated pawn penalty
- constexpr Score Isolated = S(13, 18);
-
- // Backward pawn penalty
- constexpr Score Backward = S(24, 12);
+ // Pawn penalties
+ constexpr Score Backward = S( 9, 24);
+ constexpr Score Doubled = S(11, 56);
+ constexpr Score Isolated = S( 5, 15);
// Connected pawn bonus by opposed, phalanx, #support and rank
Score Connected[2][2][3][RANK_NB];
- // Doubled pawn penalty
- constexpr Score Doubled = S(18, 38);
-
// Strength of pawn shelter for our king by [distance from edge][rank].
// RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
- { V( -9), V(64), V(77), V( 44), V( 4), V( -1), V(-11) },
- { V(-15), V(83), V(51), V(-10), V( 1), V(-10), V(-28) },
- { V(-18), V(84), V(27), V(-12), V(21), V( -7), V(-36) },
- { V( 12), V(79), V(25), V( 19), V( 9), V( -6), V(-33) }
+ { V( -6), V( 81), V( 93), V( 58), V( 39), V( 18), V( 25) },
+ { V(-43), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) },
+ { V(-10), V( 75), V( 23), V( -2), V( 32), V( 3), V( -45) },
+ { V(-39), V(-13), V(-29), V(-52), V(-48), V(-67), V(-166) }
};
- // Danger of enemy pawns moving toward our king by [type][distance from edge][rank].
- // For the unopposed and unblocked cases, RANK_1 = 0 is used when opponent has
- // no pawn on the given file, or their pawn is behind our king.
- constexpr Value StormDanger[][4][RANK_NB] = {
- { { V( 4), V( 73), V( 132), V(46), V(31) }, // Unopposed
- { V( 1), V( 64), V( 143), V(26), V(13) },
- { V( 1), V( 47), V( 110), V(44), V(24) },
- { V( 0), V( 72), V( 127), V(50), V(31) } },
- { { V( 0), V( 0), V( 19), V(23), V( 1) }, // BlockedByPawn
- { V( 0), V( 0), V( 88), V(27), V( 2) },
- { V( 0), V( 0), V( 101), V(16), V( 1) },
- { V( 0), V( 0), V( 111), V(22), V(15) } },
- { { V(22), V( 45), V( 104), V(62), V( 6) }, // Unblocked
- { V(31), V( 30), V( 99), V(39), V(19) },
- { V(23), V( 29), V( 96), V(41), V(15) },
- { V(21), V( 23), V( 116), V(41), V(15) } }
+ // Danger of enemy pawns moving toward our king by [distance from edge][rank].
+ // RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn
+ // is behind our king.
+ constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
+ { V( 89), V(107), V(123), V(93), V(57), V( 45), V( 51) },
+ { V( 44), V(-18), V(123), V(46), V(39), V( -7), V( 23) },
+ { V( 4), V( 52), V(162), V(37), V( 7), V(-14), V( -2) },
+ { V(-10), V(-14), V( 90), V(15), V( 2), V( -7), V(-16) }
};
#undef S
phalanx = neighbours & rank_bb(s);
supported = neighbours & rank_bb(s - Up);
- // A pawn is backward when it is behind all pawns of the same color on the
- // adjacent files and cannot be safely advanced.
- if (!neighbours || lever || relative_rank(Us, s) >= RANK_5)
- backward = false;
- else
- {
- // Find the backmost rank with neighbours or stoppers
- b = rank_bb(backmost_sq(Us, neighbours | stoppers));
-
- // The pawn is backward when it cannot safely progress to that rank:
- // either there is a stopper in the way on this rank, or there is a
- // stopper on adjacent file which controls the way to that rank.
- backward = (b | shift<Up>(b & adjacent_files_bb(f))) & stoppers;
-
- assert(!(backward && (forward_ranks_bb(Them, s + Up) & neighbours)));
- }
+ // A pawn is backward when it is behind all pawns of the same color
+ // on the adjacent files and cannot be safely advanced.
+ backward = !(ourPawns & pawn_attack_span(Them, s + Up))
+ && (stoppers & (leverPush | (s + Up)));
// Passed pawns will be properly scored in evaluation because we need
// full attack info to evaluate them. Include also not passed pawns
// which could become passed after one or two pawn pushes when are
// not attacked more times than defended.
if ( !(stoppers ^ lever ^ leverPush)
- && !(ourPawns & forward_file_bb(Us, s))
&& popcount(supported) >= popcount(lever) - 1
&& popcount(phalanx) >= popcount(leverPush))
e->passedPawns[Us] |= s;
void init() {
- static constexpr int Seed[RANK_NB] = { 0, 13, 24, 18, 76, 100, 175, 330 };
+ static constexpr int Seed[RANK_NB] = { 0, 13, 24, 18, 65, 100, 175, 330 };
for (int opposed = 0; opposed <= 1; ++opposed)
for (int phalanx = 0; phalanx <= 1; ++phalanx)
template<Color Us>
Value Entry::evaluate_shelter(const Position& pos, Square ksq) {
- enum { Unopposed, BlockedByPawn, Unblocked };
constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
- constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
- constexpr Bitboard BlockRanks = (Us == WHITE ? Rank2BB | Rank3BB : Rank7BB | Rank6BB);
+ constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
+ constexpr Bitboard BlockRanks = (Us == WHITE ? Rank1BB | Rank2BB : Rank8BB | Rank7BB);
- Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq));
+ Bitboard b = pos.pieces(PAWN) & ~forward_ranks_bb(Them, ksq);
Bitboard ourPawns = b & pos.pieces(Us);
Bitboard theirPawns = b & pos.pieces(Them);
- Value safety = (ourPawns & file_bb(ksq)) ? Value(5) : Value(-5);
-
- if ((theirPawns & (FileABB | FileHBB) & BlockRanks) & (ksq + Up))
- safety += 374;
+ Value safety = (shift<Down>(theirPawns) & (FileABB | FileHBB) & BlockRanks & ksq) ?
+ Value(374) : Value(5);
File center = std::max(FILE_B, std::min(FILE_G, file_of(ksq)));
for (File f = File(center - 1); f <= File(center + 1); ++f)
{
b = ourPawns & file_bb(f);
- Rank rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1;
+ int ourRank = b ? relative_rank(Us, backmost_sq(Us, b)) : 0;
b = theirPawns & file_bb(f);
- Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
+ int theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
int d = std::min(f, ~f);
- safety += ShelterStrength[d][rkUs]
- - StormDanger[rkUs == RANK_1 ? Unopposed :
- rkUs == rkThem - 1 ? BlockedByPawn : Unblocked]
- [d][rkThem];
+ safety += ShelterStrength[d][ourRank];
+ safety -= (ourRank && (ourRank == theirRank - 1)) ? 66 * (theirRank == RANK_3)
+ : UnblockedStorm[d][theirRank];
}
return safety;
/// when king square changes, which is about 20% of total king_safety() calls.
template<Color Us>
-Score Entry::do_king_safety(const Position& pos, Square ksq) {
+Score Entry::do_king_safety(const Position& pos) {
+ Square ksq = pos.square<KING>(Us);
kingSquares[Us] = ksq;
castlingRights[Us] = pos.can_castle(Us);
int minKingPawnDistance = 0;
Bitboard pawns = pos.pieces(Us, PAWN);
if (pawns)
- while (!(DistanceRingBB[ksq][minKingPawnDistance++] & pawns)) {}
+ while (!(DistanceRingBB[ksq][++minKingPawnDistance] & pawns)) {}
Value bonus = evaluate_shelter<Us>(pos, ksq);
// If we can castle use the bonus after the castling if it is bigger
- if (pos.can_castle(MakeCastling<Us, KING_SIDE>::right))
+ if (pos.can_castle(Us | KING_SIDE))
bonus = std::max(bonus, evaluate_shelter<Us>(pos, relative_square(Us, SQ_G1)));
- if (pos.can_castle(MakeCastling<Us, QUEEN_SIDE>::right))
+ if (pos.can_castle(Us | QUEEN_SIDE))
bonus = std::max(bonus, evaluate_shelter<Us>(pos, relative_square(Us, SQ_C1)));
return make_score(bonus, -16 * minKingPawnDistance);
}
// Explicit template instantiation
-template Score Entry::do_king_safety<WHITE>(const Position& pos, Square ksq);
-template Score Entry::do_king_safety<BLACK>(const Position& pos, Square ksq);
+template Score Entry::do_king_safety<WHITE>(const Position& pos);
+template Score Entry::do_king_safety<BLACK>(const Position& pos);
} // namespace Pawns
projects / stockfish / blobdiff