Help with geometry please
In my speedlimit 'droid app I search my database for signs "pointing" in same direction as you are travelling and then it matches up the nearest one.
Minor problem is that that it will match up to a sign that is "behind" you as its nearer than the nearest one ahead of you.
Its not a real problem as it only changes the speedlimit if a sign is within a 100m range but I'd like my app to ignore signs that are "behind" me :)
So the info available is a database of signs with the direction they "point" in (0-369 0 being North) and x y (lat long) positions and I know where I am x y (lat long) pos and which direction I'm travelling in (0-359 0 being North).
Anyone up for the maths challenge? :)