[Unity] unity loading bar 구현

using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using DG.Tweening;
using UnityEngine.SceneManagement;

public delegate void ProgressDelegate(float progress);

public class LoadSceneAsyncProgress : MonoBehaviour {
	public Image ProgressBar;
	public CanvasGroup CG_Loading;

	void Start() {
		CG_Loading.DOFade (0.5f, 0.5f).SetEase (Ease.Linear).SetLoops (-1, LoopType.Yoyo);
		StartCoroutine(LoadSceneAsyncByName("FamilyHomeVI_SR", OnLoadLevelProgressUpdate));

	}
	
	public static IEnumerator LoadSceneAsyncByName(string nextLevel, ProgressDelegate progressDelegate) {
		AsyncOperation async = SceneManager.LoadSceneAsync(nextLevel);
	
		while (!async.isDone) {
			progressDelegate (async.progress);
			async.allowSceneActivation = async.progress > 0.8;
			yield return null;
		}
	}

	private void OnLoadLevelProgressUpdate(float progress) {
		ProgressBar.fillAmount = progress;
		Debug.Log ("async.progress: " + progress);
	}
}

참조 : https://gist.github.com/crowjdh/26272392e425063cbd69586cd542a46d

Getting progress while loading scene in Unity using SceneManager.LoadSceneAsync.

참조 : https://docs.unity3d.com/ScriptReference/AsyncOperation-progress.html

Unity - Scripting API: AsyncOperation.progress