// Weakness of our pawn shelter in front of the king by [distance from edge][rank]
const Value ShelterWeakness[][RANK_NB] = {
- { V(100), V(13), V(24), V(64), V(89), V( 93), V(104) },
- { V(110), V( 1), V(29), V(75), V(96), V(102), V(107) },
- { V(102), V( 0), V(39), V(74), V(88), V(101), V( 98) },
- { V( 88), V( 4), V(33), V(67), V(92), V( 94), V(107) } };
+ { V( 99), V(23), V(24), V(54), V(85), V( 93), V(107) },
+ { V(119), V( 2), V(28), V(72), V(96), V(104), V(114) },
+ { V(103), V( 6), V(47), V(74), V(84), V(103), V( 94) },
+ { V( 78), V(10), V(41), V(64), V(88), V( 92), V(115) } };
// Danger of enemy pawns moving toward our king by [type][distance from edge][rank]
const Value StormDanger[][4][RANK_NB] = {
- { { V( 0), V( 63), V( 128), V(43), V(27) },
- { V( 0), V( 62), V( 131), V(44), V(26) },
- { V( 0), V( 59), V( 121), V(50), V(28) },
- { V( 0), V( 62), V( 127), V(54), V(28) } },
- { { V(24), V( 40), V( 93), V(42), V(22) },
- { V(24), V( 28), V( 101), V(38), V(20) },
- { V(24), V( 32), V( 95), V(36), V(23) },
- { V(27), V( 24), V( 99), V(36), V(24) } },
- { { V( 0), V( 0), V( 81), V(16), V( 6) },
- { V( 0), V( 0), V( 165), V(29), V( 9) },
- { V( 0), V( 0), V( 163), V(23), V(12) },
- { V( 0), V( 0), V( 161), V(28), V(13) } },
- { { V( 0), V(-296), V(-299), V(55), V(25) },
- { V( 0), V( 67), V( 131), V(46), V(21) },
- { V( 0), V( 65), V( 135), V(50), V(31) },
- { V( 0), V( 62), V( 128), V(51), V(24) } } };
+ { { V( 0), V( 65), V( 125), V(37), V(30) },
+ { V( 0), V( 57), V( 136), V(39), V(24) },
+ { V( 0), V( 50), V( 114), V(45), V(29) },
+ { V( 0), V( 58), V( 129), V(56), V(34) } },
+ { { V(20), V( 45), V( 91), V(47), V(20) },
+ { V(25), V( 23), V( 105), V(38), V(14) },
+ { V(21), V( 37), V( 99), V(35), V(21) },
+ { V(30), V( 18), V( 105), V(38), V(28) } },
+ { { V( 0), V( 0), V( 81), V(13), V( 4) },
+ { V( 0), V( 0), V( 169), V(30), V( 4) },
+ { V( 0), V( 0), V( 166), V(24), V( 6) },
+ { V( 0), V( 0), V( 164), V(24), V(11) } },
+ { { V( 0), V(-289), V(-297), V(57), V(29) },
+ { V( 0), V( 66), V( 136), V(43), V(16) },
+ { V( 0), V( 66), V( 141), V(50), V(31) },
+ { V( 0), V( 63), V( 126), V(52), V(23) } } };
// 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 Value MaxSafetyBonus = V(257);
+ const Value MaxSafetyBonus = V(252);
#undef S
#undef V
lever = theirPawns & pawnAttacksBB[s];
// Test for backward pawn.
- // If the pawn is passed, isolated, or connected it cannot be
+ // If the pawn is passed, isolated, connected or a lever it cannot be
// backward. If there are friendly pawns behind on adjacent files
- // or if it can capture an enemy pawn it cannot be backward either.
- if ( (passed | isolated | connected)
- || (ourPawns & pawn_attack_span(Them, s))
- || (pos.attacks_from<PAWN>(s, Us) & theirPawns))
+ // it cannot be backward either.
+ if ( (passed | isolated | lever | connected)
+ || (ourPawns & pawn_attack_span(Them, s)))
backward = false;
else
{