XNA 4.0 Game Development by Example Beginner's Guide

Time for action – waypoint management

1. Add the AddWaypoint() method to the Enemy class:

   public void AddWaypoint(Vector2 waypoint)
   {
       waypoints.Enqueue(waypoint);
   }

2. Add the WaypointReached() method to the Enemy class:

   public bool WaypointReached()
   {
       if (Vector2.Distance(EnemySprite.Location, currentWaypoint) < 
           (float)EnemySprite.Source.Width/2)
       {
           return true;
       }
       else
       {
           return false;
       }
   }

3. Add the IsActive() method to the Enemy class:

   public bool IsActive()
   {
       if (Destroyed)
       {
           return false;
       }
   
       if (waypoints.Count > 0)
       {
           return true;
       }
   
       if (WaypointReached())
       {
           return false;
       }
   
       return true;
   }

What just happened?

When a new waypoint is added to the enemy's route, it is enqueued to the waypoints queue. When WaypointReached() is called, the function checks to see ...