{ S(25, 30), S(36, 35), S(40, 35), S(40, 35),
S(40, 35), S(40, 35), S(36, 35), S(25, 30) } };
- // Backward pawn penalty by opposed flag and file
- const Score Backward[2][FILE_NB] = {
- { S(30, 42), S(43, 46), S(49, 46), S(49, 46),
- S(49, 46), S(49, 46), S(43, 46), S(30, 42) },
- { S(20, 28), S(29, 31), S(33, 31), S(33, 31),
- S(33, 31), S(33, 31), S(29, 31), S(20, 28) } };
+ // Backward pawn penalty by opposed flag
+ const Score Backward[2] = { S(67, 42), S(49, 24) };
// Connected pawn bonus by opposed, phalanx, twice supported and rank
Score Connected[2][2][2][RANK_NB];
// Weakness of our pawn shelter in front of the king by [distance from edge][rank]
const Value ShelterWeakness[][RANK_NB] = {
- { V( 99), V(20), V(26), V(54), V(85), V( 92), V(108) },
- { V(117), V( 1), V(27), V(71), V(94), V(104), V(118) },
- { V(104), V( 4), V(51), V(76), V(82), V(102), V( 97) },
- { V( 80), V(12), V(43), V(65), V(88), V( 91), V(115) } };
+ { V( 97), V(21), V(26), V(51), V(87), V( 89), V( 99) },
+ { V(120), V( 0), V(28), V(76), V(88), V(103), V(104) },
+ { V(101), V( 7), V(54), V(78), V(77), V( 92), V(101) },
+ { V( 80), V(11), V(44), V(68), V(87), V( 90), V(119) } };
// Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
const Value StormDanger[][4][RANK_NB] = {
- { { V( 0), V( 65), V( 126), V(36), V(30) },
- { V( 0), V( 55), V( 135), V(36), V(23) },
- { V( 0), V( 47), V( 116), V(45), V(26) },
- { V( 0), V( 62), V( 127), V(57), V(34) } },
- { { V(21), V( 45), V( 93), V(50), V(19) },
- { V(23), V( 24), V( 105), V(41), V(13) },
- { V(23), V( 36), V( 101), V(38), V(20) },
- { V(30), V( 19), V( 110), V(41), V(27) } },
- { { V( 0), V( 0), V( 81), V(14), V( 4) },
- { V( 0), V( 0), V( 169), V(30), V( 3) },
- { V( 0), V( 0), V( 168), V(24), V( 5) },
- { V( 0), V( 0), V( 162), V(26), V(10) } },
- { { V( 0), V(-283), V(-298), V(57), V(29) },
- { V( 0), V( 63), V( 137), V(42), V(18) },
- { V( 0), V( 67), V( 145), V(49), V(33) },
- { V( 0), V( 62), V( 126), V(53), V(21) } } };
+ { { V( 0), V( 67), V( 134), V(38), V(32) },
+ { V( 0), V( 57), V( 139), V(37), V(22) },
+ { V( 0), V( 43), V( 115), V(43), V(27) },
+ { V( 0), V( 68), V( 124), V(57), V(32) } },
+ { { V(20), V( 43), V( 100), V(56), V(20) },
+ { V(23), V( 20), V( 98), V(40), V(15) },
+ { V(23), V( 39), V( 103), V(36), V(18) },
+ { V(28), V( 19), V( 108), V(42), V(26) } },
+ { { V( 0), V( 0), V( 75), V(14), V( 2) },
+ { V( 0), V( 0), V( 150), V(30), V( 4) },
+ { V( 0), V( 0), V( 160), V(22), V( 5) },
+ { V( 0), V( 0), V( 166), V(24), V(13) } },
+ { { V( 0), V(-283), V(-281), V(57), V(31) },
+ { V( 0), V( 58), V( 141), V(39), V(18) },
+ { V( 0), V( 65), V( 142), V(48), V(32) },
+ { V( 0), V( 60), V( 126), V(51), V(19) } } };
// Max bonus for king safety. Corresponds to start position with all the pawns
// in front of the king and no enemy pawn on the horizon.
const Square Right = (Us == WHITE ? DELTA_NE : DELTA_SW);
const Square Left = (Us == WHITE ? DELTA_NW : DELTA_SE);
- Bitboard b, neighbours, doubled, connected, supported, phalanx;
+ Bitboard b, neighbours, doubled, supported, phalanx;
Square s;
- bool passed, isolated, opposed, backward, lever;
+ bool passed, isolated, opposed, backward, lever, connected;
Score score = SCORE_ZERO;
- const Square* pl = pos.
list<PAWN>(Us);
+ const Square* pl = pos.
squares<PAWN>(Us);
const Bitboard* pawnAttacksBB = StepAttacksBB[make_piece(Us, PAWN)];
Bitboard ourPawns = pos.pieces(Us , PAWN);
isolated = !neighbours;
// Test for backward pawn.
- // If the pawn is passed, isolated, connected or a lever it cannot be
+ // If the pawn is passed, isolated, lever or connected it cannot be
// backward. If there are friendly pawns behind on adjacent files
- // it cannot be backward either.
+ // or if it is sufficiently advanced, it cannot be backward either.
if ( (passed | isolated | lever | connected)
- || (ourPawns & pawn_attack_span(Them, s)))
+ || (ourPawns & pawn_attack_span(Them, s))
+ || (relative_rank(Us, s) >= RANK_5))
backward = false;
else
{
if (isolated)
score -= Isolated[opposed][f];
- if (!supported && !isolated)
- score -= UnsupportedPawnPenalty;
-
- if (doubled)
- score -= Doubled[f] / distance<Rank>(s, frontmost_sq(Us, doubled));
+ else if (backward)
+ score -= Backward[opposed];
- if (backward)
- score -= Backward[opposed][f];
+ else if (!supported)
+ score -= UnsupportedPawnPenalty;
if (connected)
score += Connected[opposed][!!phalanx][more_than_one(supported)][relative_rank(Us, s)];
+ if (doubled)
+ score -= Doubled[f] / distance<Rank>(s, frontmost_sq(Us, doubled));
+
if (lever)
score += Lever[relative_rank(Us, s)];
}
kingSquares[Us] = ksq;
castlingRights[Us] = pos.can_castle(Us);
- minKingPawnDistance[Us] = 0;
+ int minKingPawnDistance = 0;
Bitboard pawns = pos.pieces(Us, PAWN);
if (pawns)
- while (!(DistanceRingBB[ksq][minKingPawnDistance[Us]++] & pawns)) {}
+ while (!(DistanceRingBB[ksq][minKingPawnDistance++] & pawns)) {}
if (relative_rank(Us, ksq) > RANK_4)
- return make_score(0, -16 * minKingPawnDistance[Us]);
+ return make_score(0, -16 * minKingPawnDistance);
Value bonus = shelter_storm<Us>(pos, ksq);
if (pos.can_castle(MakeCastling<Us, QUEEN_SIDE>::right))
bonus = std::max(bonus, shelter_storm<Us>(pos, relative_square(Us, SQ_C1)));
- return make_score(bonus, -16 * minKingPawnDistance[Us]);
+ return make_score(bonus, -16 * minKingPawnDistance);
}
// Explicit template instantiation
projects / stockfish / blobdiff