#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(27, 30), S(13, 18) };
// Backward pawn penalty by opposed flag
- const Score Backward[2] = { S(56, 33), S(41, 19) };
+ const Score Backward[] = { S(40, 26), S(24, 12) };
- // Unsupported pawn penalty for pawns which are neither isolated or backward
- const Score Unsupported = S(17, 8);
-
- // Connected pawn bonus by opposed, phalanx, twice supported and rank
- Score Connected[2][2][2][RANK_NB];
+ // Connected pawn bonus by opposed, phalanx, #support and rank
+ Score Connected[2][2][3][RANK_NB];
// Doubled pawn penalty
const Score Doubled = S(18, 38);
const Square Left = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
Bitboard b, neighbours, stoppers, doubled, supported, phalanx;
+ Bitboard lever, leverPush;
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)];
- Bitboard ourPawns = pos.pieces(Us , PAWN);
+ Bitboard ourPawns = pos.pieces( Us, PAWN);
Bitboard theirPawns = pos.pieces(Them, PAWN);
e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
// Flag the pawn
- opposed = theirPawns & forward_bb(Us, s);
+ opposed = theirPawns & forward_file_bb(Us, s);
stoppers = theirPawns & passed_pawn_mask(Us, s);
- lever = theirPawns & pawnAttacksBB[s];
- doubled = ourPawns & (s + Up);
+ lever = theirPawns & PawnAttacks[Us][s];
+ leverPush = theirPawns & PawnAttacks[Us][s + Up];
+ doubled = ourPawns & (s - Up);
neighbours = ourPawns & adjacent_files_bb(f);
phalanx = neighbours & rank_bb(s);
supported = neighbours & rank_bb(s - Up);
- connected = supported | phalanx;
// A pawn is backward when it is behind all pawns of the same color on the
// adjacent files and cannot be safely advanced.
// stopper on adjacent file which controls the way to that rank.
backward = (b | shift<Up>(b & adjacent_files_bb(f))) & stoppers;
- assert(!backward || !(pawn_attack_span(Them, s + Up) & neighbours));
+ assert(!(backward && (forward_ranks_bb(Them, s + Up) & neighbours)));
}
// 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_file_bb(Us, s))
+ && popcount(supported) >= popcount(lever)
+ && popcount(phalanx) >= popcount(leverPush))
e->passedPawns[Us] |= s;
+ else if ( stoppers == SquareBB[s + Up]
+ && relative_rank(Us, s) >= RANK_5)
+ {
+ b = shift<Up>(supported) & ~theirPawns;
+ while (b)
+ if (!more_than_one(theirPawns & PawnAttacks[Us][pop_lsb(&b)]))
+ e->passedPawns[Us] |= s;
+ }
+
// Score this pawn
- if (!neighbours)
+ if (supported | phalanx)
+ score += Connected[opposed][!!phalanx][popcount(supported)][relative_rank(Us, s)];
+
+ else if (!neighbours)
score -= Isolated[opposed];
else if (backward)
score -= Backward[opposed];
- else if (!supported)
- score -= Unsupported;
-
- if (connected)
- score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
-
- if (doubled)
+ if (doubled && !supported)
score -= Doubled;
if (lever)
void init() {
- static const int Seed[RANK_NB] = { 0, 8, 19, 13, 71, 94, 169, 324 };
+ static const int Seed[RANK_NB] = { 0, 13, 24, 18, 76, 100, 175, 330 };
for (int opposed = 0; opposed <= 1; ++opposed)
for (int phalanx = 0; phalanx <= 1; ++phalanx)
- for (int apex = 0; apex <= 1; ++apex)
+ for (int support = 0; support <= 2; ++support)
for (Rank r = RANK_2; r < RANK_8; ++r)
{
- int v = (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed;
- v += (apex ? v / 2 : 0);
- Connected[opposed][phalanx][apex][r] = make_score(v, v * (r-2) / 4);
+ int v = 17 * support;
+ v += (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed;
+
+ Connected[opposed][phalanx][support][r] = make_score(v, v * (r - 2) / 4);
}
}
enum { BlockedByKing, Unopposed, BlockedByPawn, Unblocked };
- Bitboard b = pos.pieces(PAWN) & (in_front_bb(Us, rank_of(ksq)) | rank_bb(ksq));
+ Bitboard b = pos.pieces(PAWN) & (forward_ranks_bb(Us, ksq) | rank_bb(ksq));
Bitboard ourPawns = b & pos.pieces(Us);
Bitboard theirPawns = b & pos.pieces(Them);
Value safety = MaxSafetyBonus;
b = ourPawns & file_bb(f);
Rank rkUs = b ? relative_rank(Us, backmost_sq(Us, b)) : RANK_1;
- b = theirPawns & file_bb(f);
+ 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;
projects / stockfish / blobdiff