Coroutine Countdown Timer being extremely slow

Question

Hey guys so just as a disclaimer I'm relatively new to programming so if I'm making some super obvious mistake please go easy on me

So I'm trying to create a higher customizable Countdown timer for my game, and I want it to be able to be accurate to 0.01 Seconds. I decided I would use the Coroutine method for creating my timer instead of the delta-time one I have seen a couple of times, thinking that this would be a more efficient approach. My game is not very intensive and thus easily runs on hundreds of frames per second, so I thought that using Waitforseconds(0.01) is going to work better because it only needs to be called 100 times every second rather than multiple hundreds. however, I have come into a major issue with my timer. It is EXTREMELY slow. I ran the countdown timer on google and mine side by side starting at 25 seconds and it beat mine out by ten seconds. I even tried adding a artifical delay thinking the waitforseconds function was overshooting, so I would have the time tick down 0.01 seconds when a bit less then that had passed, but my results ended up being sort of inconsistent. Here is my code

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 public class TimerScript : MonoBehaviour
 {
   public Text textDisplay;
   private double secondsLeft = 30;
   public bool takingAway = false;
 
    private string Texttodisplay;
    
 
    public int Milisecondsdigits = 2;
   void Start()
   {
       textDisplay = GetComponent<Text>();
       Texttodisplay = "00:" + secondsLeft;
       
       if(Milisecondsdigits == 0)
       {
           Milisecondsdigits = -1;
       }
   }
 
     void Update()
     {
         if (takingAway == false && secondsLeft > 0)
         {
             StopAllCoroutines();
             StartCoroutine(TimerTake());
         }
         
         if(Texttodisplay.Length > 8 - (Mathf.Abs(Milisecondsdigits -2)))
         {
             Texttodisplay = Texttodisplay.Substring(0,8- (Mathf.Abs(Milisecondsdigits -2)));
         }
 
         textDisplay.text = Texttodisplay;
     }
 
     IEnumerator TimerTake()
     {
         takingAway = true;
         yield return new WaitForSeconds(0.01f);
         secondsLeft -= 0.01;
         if(secondsLeft < 10)
         {
             Texttodisplay = "00:0" + secondsLeft;
 
         }
         
 
         else 
         {
              Texttodisplay = "00:" + secondsLeft;
 
         }
 
         takingAway = false;
     }
 
 }

could somebody please let me know how I could cause this to become more accurate or why it's acting extremely inaccurate currently :/

Answer 1

If you want to have higher accurate Timer I suggest using update as its much faster than doing in coroutine. Starting coroutines have a cost.

On top of that starting, a new instance of coroutine in every update is a bad approach. Pick one, Either use fully coroutine approach or all in Update() approach.

Additionally try to use stringValue.ToString( "FormatString" ) for formatting which is less garbage generating.

https://docs.microsoft.com/en-us/dotnet/standard/base-types/how-to-pad-a-number-with-leading-zeros

Read more about string and Garbage, https://answers.unity.com/questions/1334070/how-to-avoid-garbage-with-strings.html

See below my approach for similar work,

 public class CountDownTimer : MonoBehaviour
 {
     [SerializeField]
     private Text _TextDisplay;
 
     public void StartCountDown( float seconds )
     { 
         StopCoroutine("IEnuCountDown");
         StartCoroutine(IEnuCountDown(_TextDisplay, seconds ));
     }
 
     IEnumerator IEnuCountDown( Text textBox, float countDown )
     {
         float timeLeft = countDown;
 
         while( timeLeft > 0f )
         {
             yield return new WaitForEndOfFrame();
             timeLeft -= Time.deltaTime;
 
             if( timeLeft < 0 )
             {
                 timeLeft = 0;
                 textBox.text = timeLeft.ToString( "00.##" );
                 break;
             }
             else
             {
                 textBox.text = "00.00";
             }
         }
 
         yield return 1;
     }
 
 #if UNITY_EDITOR
     /// <summary>
     /// https://docs.unity3d.com/ScriptReference/ContextMenu.html
     /// </summary>
     [ContextMenu("Test Me")]
     public void TestMe()
     { 
         StartCountDown( 10f );
     }
 #endif
 }

Coroutine Countdown Timer being extremely slow

1 Reply

Your answer

Follow this Question

Related Questions