#undef S
const Score Tempo = make_score(24, 11);
- const Score BishopPin = make_score(66, 11);
const Score RookOn7th = make_score(11, 20);
const Score QueenOn7th = make_score( 3, 8);
const Score RookOnPawn = make_score(10, 28);
const int BishopCheck = 2;
const int KnightCheck = 3;
- // KingExposed[Square] contains penalties based on the position of the
- // defending king, indexed by king's square (from white's point of view).
- const int KingExposed[] = {
- 2, 0, 2, 5, 5, 2, 0, 2,
- 2, 2, 4, 8, 8, 4, 2, 2,
- 7, 10, 12, 12, 12, 12, 10, 7,
- 15, 15, 15, 15, 15, 15, 15, 15,
- 15, 15, 15, 15, 15, 15, 15, 15,
- 15, 15, 15, 15, 15, 15, 15, 15,
- 15, 15, 15, 15, 15, 15, 15, 15,
- 15, 15, 15, 15, 15, 15, 15, 15
- };
-
// KingDanger[Color][attackUnits] contains the actual king danger weighted
// scores, indexed by color and by a calculated integer number.
Score KingDanger[COLOR_NB][128];
if (ei.attackedBy[Them][PAWN] & s)
score -= ThreatenedByPawn[Piece];
- // Otherwise give a bonus if we are a bishop and can pin a piece or can
- // give a discovered check through an x-ray attack.
- else if ( Piece == BISHOP
- && (PseudoAttacks[Piece][pos.king_square(Them)] & s)
- && !more_than_one(BetweenBB[s][pos.king_square(Them)] & pos.pieces()))
- score += BishopPin;
-
// Penalty for bishop with same coloured pawns
if (Piece == BISHOP)
score -= BishopPawns * ei.pi->pawns_on_same_color_squares(Us, s);
// Initialize the 'attackUnits' variable, which is used later on as an
// index to the KingDanger[] array. The initial value is based on the
// number and types of the enemy's attacking pieces, the number of
- // attacked and undefended squares around our king, the square of the
- // king, and the quality of the pawn shelter.
+ // attacked and undefended squares around our king and the quality of
+ // the pawn shelter (current 'score' value).
attackUnits = std::min(20, (ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them]) / 2)
+ 3 * (ei.kingAdjacentZoneAttacksCount[Them] + popcount<Max15>(undefended))
- + KingExposed[relative_square(Us, ksq)]
- mg_value(score) / 32;
// Analyse the enemy's safe queen contact checks. Firstly, find the