ScreenFader.cs Freezing and Abnormal Fading Speed When Frequently Called

[TruthZY]

Issue Description

There are issues with "ScreenFader.cs" when it is frequently called, such as freezing and abnormal fading speed. For instance, when I switch scenes in quick succession, like entering a scene and immediately exiting to the main menu, it may freeze.

Steps to Reproduce

Create a new script:

public class Test : MonoBehaviour
{
    public bool isFading; // for observation

    void Update()
    {
        if (Input.GetKeyDown(KeyCode.E))
        {
            StartCoroutine(ScreenFader.FadeSceneIn());
        }
        if (Input.GetKeyDown(KeyCode.R))
        {
            StartCoroutine(ScreenFader.FadeSceneOut());
        }

        isFading = ScreenFader.IsFading;
    }
}

Set Fade Duration to 1 or above, repeatedly pressing R and E will trigger the issue.

Solution

In the file Gamekit3D/Assets/3DGamekit/Packages/SceneManagement/Runtime/ScreenFader.cs, modify the Fade method as follows:

  protected IEnumerator Fade(float finalAlpha, CanvasGroup canvasGroup)
  {
      m_IsFading = true;
      canvasGroup.blocksRaycasts = true;
      float fadeSpeed = Mathf.Abs(canvasGroup.alpha - finalAlpha) / fadeDuration;
      // modify
      while (Mathf.Abs(canvasGroup.alpha - finalAlpha) > 0.1f)
      {
          canvasGroup.alpha = Mathf.MoveTowards(canvasGroup.alpha, finalAlpha,
              fadeSpeed * Time.deltaTime);
          yield return null;
      }
      canvasGroup.alpha = finalAlpha;
      m_IsFading = false;
      canvasGroup.blocksRaycasts = false;
  }

When alpha, finalAlpha, fadeSpeed*Time.deltaTime is close to 0, because the precision of the floating-point number loses the correct result.