Obviously the definition of winning is having gone past the last pipe.

So, on the face of it, we're going to need to constantly check the position of the last pipe and see where it is in relation to the bird. We probably want the game to be "won" a short distance after the last pipe (not right on it).

We also need some sort of visual indication of a "finish line", which gets closer and closer once we're through all the pipes.

That sounds really difficult !