S(40, 35), S(40, 35), S(36, 35), S(25, 30) } };
// Backward pawn penalty by opposed flag
- const Score Backward[2] = { S(67, 56), S(49, 40) };
+ 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];
// Test for backward pawn.
// 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
{