update asset system

新增了初始化参数LoadingMaxTimeSlice
移除了参数AssetLoadingMaxNumber

Assets/YooAsset/Runtime/AssetSystem/AssetSystem.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Diagnostics;
 using UnityEngine;
 using UnityEngine.SceneManagement;
 
@@ -20,25 +21,37 @@ namespace YooAsset
 		private bool _isUnloadSafe = true;
 		private string _packageName;
 		private bool _simulationOnEditor;
-		public int LoadingMaxNumber { private set; get; }
+		private long _loadingMaxTimeSlice;
 		public int DownloadFailedTryAgain { private set; get; }
 		public IDecryptionServices DecryptionServices { private set; get; }
 		public IBundleServices BundleServices { private set; get; }
 
+		// 计时器相关
+		private Stopwatch _watch;
+		private long _frameTime;
+		private bool IsBusy
+		{
+			get
+			{
+				return _watch.ElapsedMilliseconds - _frameTime >= _loadingMaxTimeSlice;
+			}
+		}
+
 
 		/// <summary>
 		/// 初始化
 		/// 注意：在使用AssetSystem之前需要初始化
 		/// </summary>
-		public void Initialize(string packageName, bool simulationOnEditor, int loadingMaxNumber, int downloadFailedTryAgain,
+		public void Initialize(string packageName, bool simulationOnEditor, long loadingMaxTimeSlice, int downloadFailedTryAgain,
 			IDecryptionServices decryptionServices, IBundleServices bundleServices)
 		{
 			_packageName = packageName;
 			_simulationOnEditor = simulationOnEditor;
-			LoadingMaxNumber = loadingMaxNumber;
+			_loadingMaxTimeSlice = loadingMaxTimeSlice;
 			DownloadFailedTryAgain = downloadFailedTryAgain;
 			DecryptionServices = decryptionServices;
 			BundleServices = bundleServices;
+			_watch = Stopwatch.StartNew();
 		}
 
 		/// <summary>
@@ -46,6 +59,8 @@ namespace YooAsset
 		/// </summary>
 		public void Update()
 		{
+			_frameTime = _watch.ElapsedMilliseconds;
+
 			// 更新加载器	
 			foreach (var loader in _loaderList)
 			{
@@ -56,22 +71,11 @@ namespace YooAsset
 			// 注意：循环更新的时候，可能会扩展列表
 			// 注意：不能限制场景对象的加载
 			_isUnloadSafe = false;
-			int loadingCount = 0;
 			for (int i = 0; i < _providerList.Count; i++)
 			{
-				var provider = _providerList[i];
-				if (provider.IsSceneProvider())
-				{
-					provider.Update();
-				}
-				else
-				{
-					if (loadingCount < LoadingMaxNumber)
-						provider.Update();
-
-					if (provider.IsDone == false)
-						loadingCount++;
-				}
+				if (IsBusy)
+					break;
+				_providerList[i].Update();
 			}
 			_isUnloadSafe = true;
 		}

Assets/YooAsset/Runtime/InitializeParameters.cs

@@ -39,13 +39,14 @@ namespace YooAsset
 		public IDecryptionServices DecryptionServices = null;
 
 		/// <summary>
-		/// 资源加载的最大数量
+		/// 资源加载每帧处理的最大时间片段
 		/// 注意：默认值为MaxValue
 		/// </summary>
-		public int AssetLoadingMaxNumber = int.MaxValue;
+		public long LoadingMaxTimeSlice = long.MaxValue;
 		
 		/// <summary>
 		/// 下载失败尝试次数
+		/// 注意：默认值为MaxValue
 		/// </summary>
 		public int DownloadFailedTryAgain = int.MaxValue;
 	}

Assets/YooAsset/Runtime/ResourcePackage.cs

@@ -88,7 +88,7 @@ namespace YooAsset
 				_bundleServices = editorSimulateModeImpl;
 				_playModeServices = editorSimulateModeImpl;
 				_assetSystemImpl.Initialize(PackageName, true,
-					parameters.AssetLoadingMaxNumber, parameters.DownloadFailedTryAgain,
+					parameters.LoadingMaxTimeSlice, parameters.DownloadFailedTryAgain,
 					parameters.DecryptionServices, _bundleServices);
 
 				var initializeParameters = parameters as EditorSimulateModeParameters;
@@ -100,7 +100,7 @@ namespace YooAsset
 				_bundleServices = offlinePlayModeImpl;
 				_playModeServices = offlinePlayModeImpl;
 				_assetSystemImpl.Initialize(PackageName, false,
-					parameters.AssetLoadingMaxNumber, parameters.DownloadFailedTryAgain,
+					parameters.LoadingMaxTimeSlice, parameters.DownloadFailedTryAgain,
 					parameters.DecryptionServices, _bundleServices);
 
 				var initializeParameters = parameters as OfflinePlayModeParameters;
@@ -112,7 +112,7 @@ namespace YooAsset
 				_bundleServices = hostPlayModeImpl;
 				_playModeServices = hostPlayModeImpl;
 				_assetSystemImpl.Initialize(PackageName, false,
-					parameters.AssetLoadingMaxNumber, parameters.DownloadFailedTryAgain,
+					parameters.LoadingMaxTimeSlice, parameters.DownloadFailedTryAgain,
 					parameters.DecryptionServices, _bundleServices);
 
 				var initializeParameters = parameters as HostPlayModeParameters;
@@ -188,10 +188,10 @@ namespace YooAsset
 				throw new NotImplementedException();
 
 			// 检测参数范围
-			if (parameters.AssetLoadingMaxNumber < 1)
+			if (parameters.LoadingMaxTimeSlice < 10)
 			{
-				parameters.AssetLoadingMaxNumber = 1;
-				YooLogger.Warning($"{nameof(parameters.AssetLoadingMaxNumber)} minimum value is 1");
+				parameters.LoadingMaxTimeSlice = 10;
+				YooLogger.Warning($"{nameof(parameters.LoadingMaxTimeSlice)} minimum value is 10 milliseconds.");
 			}
 			if (parameters.DownloadFailedTryAgain < 1)
 			{