I have tried to reverse-engineer it, but not worked it out yet.  It seems to work though.<p>In Sweden you can make long journeys on fairly straight roads through forest meeting only the occasional other vehicle, very rarely seeing a pedestrian, and mostly keeping an eye out for movement between the trees that may be a deer or elk or boar about to run out in front of you.<p>Deer make small dents, badgers are like hitting stones, wild pigs can write off the car and elk are absolutely lethal.  You actually get taught that, if a collision is inevitable, to aim for the hind legs to maximize your chances of survival.<p>Must be much the same in much of the USA, Canada, Russia etc.