- if ( r
- && type_of(move) == NORMAL
- && type_of(pos.piece_on(to_sq(move))) != PAWN
- && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
- r = std::max(DEPTH_ZERO, r - ONE_PLY);
+ else if ( type_of(move) == NORMAL
+ && type_of(pos.piece_on(to_sq(move))) != PAWN
+ && pos.see(make_move(to_sq(move), from_sq(move))) < VALUE_ZERO)
+ r -= ONE_PLY;
+
+ // Decrease/increase reduction for moves with a good/bad history
+ int rHist = (val - 10000) / 20000;
+ r = std::max(DEPTH_ZERO, r - rHist * ONE_PLY);