Basic RTS movement using Navmesh & co-routine?

Question

I'm trying to make characters to follow moving object by clicking on it (Basic RTS movement), and I've heard that using co-routine is saving more computing power than using void Update. However, I'm quite new to co-routine and I need some help.

• Also, I feel like there's no need to include clicking code since it's a simple click then call function of this script.

Here are my questions

1. If my character use MoveToPoint() first, then using FollowTarget() will need player to click on object twice to start following rather than once, I can't seem to figured out why..

2. When player click multiple time on the same object, multiple UpdatePosition() will run, How do I make it run once on that object? (My friend vigorously clicking on an object in attempt to make character walk faster, when it obviously does not. And now there's like 10 co-routine running..)

3. There's more than one character, and when the other stop following, it seems like another character's co-routine also stopped as well. How do I make them follow & unfollow individually without affecting one another?

   void Start () 
   {
       agent = GetComponent<NavMeshAgent>();
   }
   
   IEnumerator UpdatePosition()
   {
       while(true)
       {
           yield return new WaitForSeconds(0.5f);
           if (target != null)
           {
               agent.SetDestination(target.position);
               Debug.Log("Still looping");
           }
           else
           {
               Debug.Log("Not looping!");
           }
       }
       Debug.Log("Finished Co-routine!");
   }
   
   public void MoveToPoint (Vector3 point)
   {
       agent.SetDestination(point);
   }
   
   public void FollowTarget(Interactable newTarget)
   {
       agent.stoppingDistance = newTarget.radius * .8f;
       StartCoroutine(UpdatePosition());
       target = newTarget.transform; 
   }
   
   public void StopFollowingTarget ()
   {
       StopCoroutine(UpdatePosition());
       agent.stoppingDistance = 0f;
       target = null;
   }
   

Answer 1

1) The reason you have to click twice is probably because in your coroutine you wait for half a second first and only then you update the destination. Consider moving yield return new WaitForSeconds(0.5) to the end of your while loop.

2) This is because you call StartCoroutine every time you call FollowTarget(). You can avoid this by having a boolean for example bool coroutineRunning and setting that to false at start. Set it to true at the beginning of the coroutine and instead of calling StartCoroutine in FollowTarget, use something like

if (!coroutineRunning) 
{
   StartCoroutine(UpdatePosition())`.
}

3) Not sure. Make sure your scripts are running for each agent independently.