- m.value = (*mainHistory)[pos.side_to_move()][from_to(m)]
- + 2 * (*continuationHistory[0])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[1])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[3])[pos.moved_piece(m)][to_sq(m)]
- + (*continuationHistory[5])[pos.moved_piece(m)][to_sq(m)]
- + (ply < MAX_LPH ? 6 * (*lowPlyHistory)[ply][from_to(m)] : 0);
+ {
+ Piece pc = pos.moved_piece(m);
+ PieceType pt = type_of(pos.moved_piece(m));
+ Square from = from_sq(m);
+ Square to = to_sq(m);
+
+ // histories
+ m.value = 2 * (*mainHistory)[pos.side_to_move()][from_to(m)];
+ m.value += 2 * (*continuationHistory[0])[pc][to];
+ m.value += (*continuationHistory[1])[pc][to];
+ m.value += (*continuationHistory[3])[pc][to];
+ m.value += (*continuationHistory[5])[pc][to];
+
+ // bonus for checks
+ m.value += bool(pos.check_squares(pt) & to) * 16384;
+
+ // bonus for escaping from capture
+ m.value += threatenedPieces & from ?
+ (pt == QUEEN && !(to & threatenedByRook) ? 50000
+ : pt == ROOK && !(to & threatenedByMinor) ? 25000
+ : !(to & threatenedByPawn) ? 15000
+ : 0 )
+ : 0 ;
+
+ // malus for putting piece en prise
+ m.value -= !(threatenedPieces & from) ?
+ (pt == QUEEN ? bool(to & threatenedByRook) * 50000
+ + bool(to & threatenedByMinor) * 10000
+ + bool(to & threatenedByPawn) * 20000
+ : pt == ROOK ? bool(to & threatenedByMinor) * 25000
+ + bool(to & threatenedByPawn) * 10000
+ : pt != PAWN ? bool(to & threatenedByPawn) * 15000
+ : 0 )
+ : 0 ;
+ }