My scene don't load immediately

I have a fade out fade in script which work fine in other games. It was working fine even in the game I currently working but for unknown reasons it started to fade out slowly out of the current scene without any black screen.
here is my fade out/fade in script but I don't think this is the issue

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.UI;
5. using UnityEngine.SceneManagement;
6.  
7. public class SceneFader : MonoBehaviour {
8.  
9.     public Image img;
10.     public AnimationCurve curve;
11.     private float _progress = 0f;
12.     public Text loadingText;
13.  
14.     private void Start()
15.     {
16.         StartCoroutine(FadeIn());
17.     }
18.  
19.     public void FadeTo(string scene)
20.     {
21.         StartCoroutine(FadeOut(scene));
22.     }
23.  
24.     IEnumerator FadeIn()
25.     {
26.         float t = 1f;
27.  
28.         while(t > 0f)
29.         {
30.             t -= Time.deltaTime;
31.             float a = curve.Evaluate(t);
32.             img.color = new Color(0f, 0f, 0f, a);
33.             yield return 0;
34.         }
35.     }
36.  
37.     IEnumerator FadeOut(string scene)
38.     {
39.         AsyncOperation operation = SceneManager.LoadSceneAsync(scene);
40.  
41.         operation.allowSceneActivation = false;
42.  
43.         while(_progress < 1f)
44.         {
45.             _progress = Mathf.Clamp01(operation.progress / 0.9f);
46.  
47.             loadingText.text = "Loading... " + (int)(_progress * 100f) + "%";
48.  
49.             //Debug.Log("Loading... " + (int)(_progress * 100f) + "%");
50.  
51.             yield return null;
52.         }
53.  
54.         float t = 0f;
55.  
56.         while (t < 1f)
57.         {
58.             t += Time.deltaTime;
59.             float a = curve.Evaluate(t);
60.             img.color = new Color(0f, 0f, 0f, a);
61.             loadingText.color = new Color(1f, 1f, 1f, a);
62.             yield return 0;
63.         }
64.  
65.         //SceneManager.LoadScene(scene);
66.         operation.allowSceneActivation = true;
67.     }
68. }
69.  

 

Hard to say, as you haven't provided much to go on, and you haven't really described what isn't working. You're saying that you never see the black overlay image "img" ? Or is it always solid black? You could double check whether the sorting layer on the canvas is correct. I've messed up my fade overlay before by having another canvas on top of it, so it doesn't block out anything on that canvas.

 

it never show the black image. my sorting layer is set to 0 on fade canvas

 

Well, when you think the black image should be showing, pause Play mode, go to the scene view, and see where that image is. See if it's the right color, see if it's maybe in the wrong place, or if something has disabled it.

 

I think the problem is with loading the scene

 

Well, you haven't explained anything about the loading scene, so I don't know how to help you. Maybe you can provide more details, otherwise it sounds like you're just working through this on your own.

You've got some Debug.Log statements commented out in the code you have here. Uncomment those. Are they being called?

 

the debug say 100% loaded but the scene is still fading out

 

Oh. Maybe it's a rounding error. You might never be getting out of your "while(_progress < 1f)" loop, because it's possible that _progress only gets to something like .9999999.

Check whether you're ever getting out of the loop. If not, then make the loop dependent on operation.progress < 0.9 instead, in case it's the clamp call rounding or something.

 

if I comment this lines

Code (CSharp):

1. while (t < 1f)
2.         {
3.             t += Time.deltaTime;
4.             float a = curve.Evaluate(t);
5.             img.color = new Color(0f, 0f, 0f, a);
6.             loadingText.color = new Color(1f, 1f, 1f, a);
7.             yield return null;
8.         }

the scene load immediately

 

Ah. Maybe you're setting Time.timeScale to 0 when you start loading? If so, Time.deltaTime will be 0 each time. You can use unscaledDeltaTime instead if the game is paused.

 

that fixed the problem. thank you