WaitForSeconds before script starts

Questions & Answers
1

Hey,

I was wondering if someone can help me with my Waypoint script which runs as soon as my game starts, But i dont want it to start immediately when the game runs, i want it to start after a few seconds. So my question is how can i do this, Could i use yield WaitForSeconds? If so how and where do i add this in my script. I’ve searched the forums for about a week now, but couldn’t find anything to get it to work with my script.

Help would be greatly appreciated.

This is my Waypoint script attached to a model:

var waypoint : Transform[];
var speed : float = 20;

private var currentWaypoint : int;

function Update ()
{
    if(currentWaypoint < waypoint.length)
    {
        var target : Vector3 = waypoint[currentWaypoint].position;
        var moveDirection : Vector3 = target - transform.position;

        var velocity = rigidbody.velocity;
        if(moveDirection.magnitude < 1.0)
        {
            currentWaypoint++;
        }
        else
        {
            velocity = moveDirection.normalized * speed;
        }
    }
    rigidbody.velocity = velocity;
    RotateTowards();
}

function RotateTowards ()
{
    var target : Vector3 = waypoint[currentWaypoint].position;
    var moveDirection : Vector3 = target - transform.position;
    while(Vector3.Distance(target, transform.position) >= 1.5)
    {
        transform.rotation = Quaternion.Slerp (transform.rotation, Quaternion.LookRotation(moveDirection), 0.5* Time.deltaTime);
        transform.eulerAngles = new Vector3(0, transform.eulerAngles.y, 0);
        yield;
    }
}
3

There are (at least) three ways to do that:

(1) Use WaitForSeconds

bool run = false;

IEnumerator Start() {
  yield return new WaitForSeconds(2);
  run = true;
}

void Update() {
  if(run) {
    // Do your stuff
  }
}

(2) Compare the time of the script start with the current time to determine whether the script should run.

public float timeToWaitInSeconds = 2;

float startTime;
bool run = false;

void Start() {
  startTime = Time.time;
}

void Update() {
  if(!run) {
    if(Time.time - startTime > timeToWaitInSeconds)
      run = true;
  }
  else {
    // Do your stuff
  }
}

(3) Use Invoke

public bool run = false;

void Start() {
  Invoke("StartMe", 2);
}

void StartMe() {
  run = true;
}

void Update() {
  if(run) {
    // do your stuff
  }
}

Hint: instead of using

void Update() {
  if(run) {
    // do stuff
  }
}

you can use

void Update() {
  íf(!run) return;

  // do stuff
}

which is a bit nicer to read.

2

The difficulty relies in the fact that a “wait” cannot be used in an Update function.
You can solve this problem using a “locking” mechanism, as in the implementation below:

var lock = true;
var my_time = 3; //I suppose 3 seconds

function Start(){
   yield WaitForSeconds(my_time);
   lock = false;
}

function Update(){
   if (!lock){ 
      //Here, you put all what you actually have in your update function
      //(just remove the final "yield")
   }
}

When the game starts, you wait 3 seconds (but you can adjust this parameter, it’s just an example). After this time passed, you deactivate the lock.

Do you see the Update function now? It works only if the lock is deactivated!

Hope that this could help you.

4

This should be enough:

var DelayTime = 3.0f

function Start()
{
    enabled = false;
    yield WaitForSeconds(DelayTime);
    enabled = true;
}