SE450: Project: Lights [11/13]

Now, how do you add lights to this?

Think first about a stoplight that sits just between two road segments (no intersection).

One idea:

class Light implements CarAcceptor {
  {GREEN,RED} state;
  CarAcceptor nextRoad;
  public double distanceToObstacle(double fromPosition) {
    if state==GREEN
      return nextRoad.distanceToObstacle(fromPosition);
    else
      return 0;
  }
  void setState(...) // set the state
}

Then set up the objects as follows:

CarGenerator -> Road1 -> Light -> Road2 -> Sink

How do you coordinate two lights then?

One idea:

class TwoWayLightController implements Agent {
   Light[] lights;
   public void run() {
     // change the state of lights...
   }
}