Coroutine onscreen countdown timer?

Unity Engine
1

Ok, so i’m trying to display a countdown timer onscreen from my Coroutine’s “yield return new WaitForSeconds”. The code works but the timer is erratic, goes fast then slow then fast. I’m new to C# so I don’t know much, but if I had to guess I think the problem is it’s counting down on every frame and not in real time. I know this means i should use “Time.deltaTime”, but i’m just not sure how to impermanent it into my script.

using UnityEngine;
using UnityEngine.UI;
using System.Collections;

public class PickupManager : MonoBehaviour
{
    public GameObject _camara;
    public Image tripIcon;
    public Image shieldIcon;
    public Image speedIcon;
    public Text tripTimer;

    public float tripTime = 10f;

    private SENaturalBloomAndDirtyLens bloomScript;



    public void Start()
    {
        bloomScript = _camara.GetComponent("SENaturalBloomAndDirtyLens") as SENaturalBloomAndDirtyLens;
    }

    public void IsTripping()
    {
        StartCoroutine(Tripping());
    }

    public IEnumerator Tripping()
    {
        while (tripTime > 0f)
        {
            yield return new WaitForSeconds(1f);
            tripTimer.enabled = true;
            tripTimer.text = tripTime.ToString();
            bloomScript.bloomIntensity = 0.3f;
            bloomScript.lensDirtIntensity = 0.8f;
            tripIcon.color = new Color32(0, 33, 255, 255);
            tripTime -= 1f;
        }
        bloomScript.bloomIntensity = 0.05f;
        bloomScript.lensDirtIntensity = 0.05f;
        tripIcon.color = new Color32(0, 33, 255, 100);
        tripTimer.enabled = false;
    }

}
2

Are you calling IsTripping() from another script? If so, can you show the code that is calling it?
May also want to move

 yield return new WaitForSeconds(1f);

next to the ending brace in the while loop. This way, the text is updated before counting down to the next update.

3

Yes “IsTripping()” is called from another script.

using UnityEngine;
using System.Collections;

public class TripPickup : MonoBehaviour
{
    public GameObject tripParticleEffect;
    public PickupManager pickupManager;

    private bool isTriggered;
    private AudioSource tripSound;

    void Awake()
    {
        tripSound = gameObject.GetComponent<AudioSource>();
    }

    void Update()
    {
        if (isTriggered && !tripSound.isPlaying)
            Destroy(gameObject);

    }

    void OnTriggerEnter(Collider col)
    {
        if (col.gameObject.name == "Player")
        {
            isTriggered = true;
            pickupManager.IsTripping();
            tripSound.enabled = true;
            gameObject.GetComponent<MeshRenderer>().enabled = false;
            Instantiate(tripParticleEffect, gameObject.transform.position, Quaternion.LookRotation(Vector3.up));
        }
    }
}

I also tried moving

 yield return new WaitForSeconds(1f);

but it still counts down erratic.

EDIT:
Problem solved. It seems moving

 yield return new WaitForSeconds(1f);

right before

tripTime -= 1f;

Now it counts down like it should. Thanks for the help.

4

Moving it would not affect the countdown…it just results in behavior that is expected. Your previous code was waiting 1 second before even showing the first number of the countdown. It should follow that the first number should be displayed before waiting a second, then the countdown can continue.

Place a debug.log in the OnTriggerEnter event. I have a feeling that IsTripping() is called multiple times. This may explain the counter behavior. Short of this, the code looks correct. I don’t see why timer should not work as expected.

5

You are absolutely correct, it was getting triggered twice. The problem was

    void Update()
    {
        if (isTriggered && !tripSound.isPlaying)
            Destroy(gameObject);
    }

the delay from waiting for the audio to finish before destroying, was causing multiple collisions. So I rewrote the script using a different approach.

using UnityEngine;
using System.Collections;

//Make sure there is always an spherecollider and audiosource component on the GameObject where this script is added.
[RequireComponent(typeof(SphereCollider), typeof(AudioSource))]
public class TripPickup : MonoBehaviour
{
    public GameObject tripParticleEffect;
    public PickupManager pickupManager;
    public AudioClip tripSound;


    // Prevent audio from auto playing.
    void Start()
    {
        GetComponent<AudioSource>().playOnAwake = false;
    }

    IEnumerator OnTriggerEnter(Collider col)
    {
        if (col.gameObject.name == "Player")
        {
            //The script that we are calling it from.
            pickupManager.IsTripping();
            Instantiate(tripParticleEffect, gameObject.transform.position, Quaternion.LookRotation(Vector3.up));
            //Prevent furthur collisions & make invisible.
            GetComponent<Collider>().enabled = false;
            GetComponent<Renderer>().enabled = false;
            //Play the audio clip & wait before destroying it.
            GetComponent<AudioSource>().PlayOneShot(tripSound);
            yield return new WaitForSeconds(tripSound.length);
            //Destroy it after the audio clip is done.
            Destroy(this.gameObject);
        }
    }
}

Now it’s smooth as butter, thanks for pointing me in the right direction.

1 Like