Does exactly what you say it does...selects direction. I don't know if you have plans to work on this or if it is even possible with the API, but right now it is not as usable as I was hoping it would be because it literally selects a direction. There isn't a smooth transition (just jumps from one direction to the next...it actually does that part very smooth though) nor are non-90 degree increments supported (can't go northeast, just north or east*.) Love to see this fleshed out some more if it is even possible and you are so inclined.

*using the arrow keys only...the normal driving mode obviously still works.