#define S(mg, eg) make_score(mg, eg)
// Isolated pawn penalty by opposed flag
- const Score Isolated[2] = { S(45, 40), S(30, 27) };
+ const Score Isolated[] = { S(45, 40), S(30, 27) };
// Backward pawn penalty by opposed flag
- const Score Backward[2] = { S(56, 33), S(41, 19) };
+ const Score Backward[] = { S(56, 33), S(41, 19) };
// Unsupported pawn penalty for pawns which are neither isolated or backward
const Score Unsupported = S(17, 8);
const Square Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
+ Bitboard lever, leverPush, connected;
Square s;
- bool opposed, lever, connected, backward;
+ bool opposed, backward;
Score score = SCORE_ZERO;
const Square* pl = pos.squares<PAWN>(Us);
const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)];
opposed = theirPawns & forward_bb(Us, s);
stoppers = theirPawns & passed_pawn_mask(Us, s);
lever = theirPawns & pawnAttacksBB[s];
- doubled = ourPawns & (s + Up);
+ leverPush = theirPawns & pawnAttacksBB[s + Up];
+ doubled = ourPawns & (s - Up);
neighbours = ourPawns & adjacent_files_bb(f);
phalanx = neighbours & rank_bb(s);
supported = neighbours & rank_bb(s - Up);
}
// Passed pawns will be properly scored in evaluation because we need
- // full attack info to evaluate them.
- if (!stoppers && !(ourPawns & forward_bb(Us, s)))
+ // 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_bb(Us, s))
+ && popcount(supported) >= popcount(lever)
+ && popcount(phalanx) >= popcount(leverPush))
e->passedPawns[Us] |= s;
// Score this pawn
if (connected)
score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
- if (doubled)
- score -= Doubled;
+ if (doubled && !supported)
+ score -= Doubled;
if (lever)
score += Lever[relative_rank(Us, s)];
b = theirPawns & file_bb(f);
Rank rkThem = b ? relative_rank(Us, frontmost_sq(Them, b)) : RANK_1;
- safety -= ShelterWeakness[std::min(f, FILE_H - f)][rkUs]
+ int d = std::min(f, FILE_H - f);
+ safety -= ShelterWeakness[d][rkUs]
+ StormDanger
[f == file_of(ksq) && rkThem == relative_rank(Us, ksq) + 1 ? BlockedByKing :
rkUs == RANK_1 ? Unopposed :
rkThem == rkUs + 1 ? BlockedByPawn : Unblocked]
- [std::min(f, FILE_H - f)][rkThem];
+ [d][rkThem];
}
return safety;