TEngine 6

UnityProject/Packages/YooAsset/Runtime/ResourceManager/Operation/UnloadUnusedAssetsOperation.cs

@@ -0,0 +1,92 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+namespace YooAsset
+{
+    public sealed class UnloadUnusedAssetsOperation : AsyncOperationBase
+    {
+        private enum ESteps
+        {
+            None,
+            UnloadUnused,
+            Done,
+        }
+
+        private readonly ResourceManager _resManager;
+        private readonly int _loopCount;
+        private ESteps _steps = ESteps.None;
+
+        internal UnloadUnusedAssetsOperation(ResourceManager resourceManager, int loopCount)
+        {
+            _resManager = resourceManager;
+            _loopCount = loopCount;
+        }
+        internal override void InternalStart()
+        {
+            _steps = ESteps.UnloadUnused;
+        }
+        internal override void InternalUpdate()
+        {
+            if (_steps == ESteps.None || _steps == ESteps.Done)
+                return;
+
+            if (_steps == ESteps.UnloadUnused)
+            {
+                for (int i = 0; i < _loopCount; i++)
+                {
+                    LoopUnloadUnused();
+                }
+
+                _steps = ESteps.Done;
+                Status = EOperationStatus.Succeed;
+            }
+        }
+        internal override void InternalWaitForAsyncComplete()
+        {
+            while (true)
+            {
+                if (ExecuteWhileDone())
+                {
+                    _steps = ESteps.Done;
+                    break;
+                }
+            }
+        }
+        internal override string InternalGetDesc()
+        {
+            return $"LoopCount : {_loopCount}";
+        }
+
+        /// <summary>
+        /// 说明：资源包之间会有深层的依赖链表，需要多次迭代才可以在单帧内卸载！
+        /// </summary>
+        private void LoopUnloadUnused()
+        {
+            var removeList = new List<LoadBundleFileOperation>(_resManager.LoaderDic.Count);
+
+            // 注意：优先销毁资源提供者
+            foreach (var loader in _resManager.LoaderDic.Values)
+            {
+                loader.TryDestroyProviders();
+            }
+
+            // 获取销毁列表
+            foreach (var loader in _resManager.LoaderDic.Values)
+            {
+                if (loader.CanDestroyLoader())
+                {
+                    removeList.Add(loader);
+                }
+            }
+
+            // 销毁文件加载器
+            foreach (var loader in removeList)
+            {
+                string bundleName = loader.LoadBundleInfo.Bundle.BundleName;
+                loader.DestroyLoader();
+                _resManager.LoaderDic.Remove(bundleName);
+            }
+        }
+    }
+}