(Fixed / Answered) - Regarding IEnumerator

Unity Engine
1

Hey guys, I’m trying to use IEnumerator so I can get certain scripts / functions to wait before executing, and I really don’t understand why this is being such a pain. It’s so simple in UnityScript and then just seems stupidly overcomplex in C#…

Would love some help or explanation on this…

void Update ()
    {
        if(playerInZone == true && canSpawn == true)
        {
            StartCoroutine("SpawnZombie");
        }
    }

    IEnumerator SpawnZombie()
    {
        Debug.Log ("Waiting 15 seconds....");
        yield return new WaitForSeconds (15);
        int temp;
        temp = Random.Range(0, spawnSpots.Count);
        Instantiate(ZombiePrefab, spawnSpots[temp].transform.position, spawnSpots[temp].transform.rotation);
        zombieCount ++;
        Debug.Log ("Spawning a zombie now");
    }

These is my code, what i’m trying to make it do is, if the player is in a certain zone and they are allowed to spawn, then every 15 seconds (for example), choose a random spawn location (working fine) and spawn 1 of them.

But at the minute it waits the seconds at the start and then spawns up to the max zombie’s or waaaaay above without waiting for the seconds… Any idea’s?

2

because the StartCoroutine is in the Update function, it is starting the coroutine every frame.
You need to stop calling StartCoroutine after the first time. eg:
bool spawning = false;
if(playerInZone == true && canSpawn == true && spawning == false)…
spawning = true

1 Like
3

Because you’re calling it in your Update method.

What you can do is have a canSpawn flag, coroutine that tracks the cooldown, and a spawn function. Something like this…

IEnumerator StartCooldownTimer()
{
    canSpawn = false;
    yield return new WaitForSeconds(15f);
    canSpawn = true;
}

void AttemptSpawn()
{
    if(!canSpawn)
        return;
    StartCoroutine(StartCooldownTimer());

    // put spawn code here
}

void Update()
{
    if(playerInZone == true && canSpawn == true)
        AttemptSpawn();
}
4

Or if thats your use case just use InvokeRepeating

5

Okay thank you all for your replies.
It makes sense now :slight_smile:
And thank you @JohnnyA , I never knew about Invoke Repeating, so I’ll give it a shot :slight_smile:

// Closed (unless there is a way to actually close a thread? :slight_smile: )