Instantiate an object every few seconds

Unity Engine
1 
var dropObject : Transform;


function Update() {
	spawnPos = Random.Range(-2.5, 2.5);
	transform.position = Vector3(spawnPos,1,0);
	spawnBox();

}	

function spawnBox() {
	
	Instantiate(dropObject, transform.position, transform.rotation);
	WaitForSeconds (5);
}

So right now I’m trying to instantiate a box (falls down) based on the location of another box that is being placed at random positions. However I only want it to instantiate every few seconds. This script is attached to a box, and I assume update will be executed every frame, but when I call my coroutine within the update shouldn’t it stop it for 5 seconds? Do I need to use a loop within the update()?

I’m having problems grasping the basic concepts of unity.

thanks!

2

Try using MonoBehaviour.InvokeRepeating. You can find it in the Docs, or online here:

3

Just to clarify, Update runs every frame no matter what. You can’t stop it or delay it. So you are calling the SpawnBox function every frame, which spawns a box every frame. Also, WaitForSeconds needs to be used in conjunction with the yield statement; on its own, it won’t do what you want. But even if it was yielding, it would just wait 5 seconds and do nothing. So you’d very quickly have a large number of SpawnBox routines running simultaneously, all of them just waiting around 5 seconds after spawning the box before ending.

So, yep, InvokeRepeating is normally the way to go for things like this. However, you could also write it like so:

var dropObject : Transform; 

function Start() {
   while (true) {
      var spawnPos = Random.Range(-2.5, 2.5); 
      transform.position = Vector3(spawnPos,1,0); 
      Instantiate(dropObject, transform.position, transform.rotation);
      yield WaitForSeconds (5); 
   }
}

One advantage of doing it this way compared to InvokeRepeating is that you could yield for a random amount of time if you wanted.

–Eric