Fixes for clean shutdown.

Author: ChunkTreasure1

Engine/Source/AssetSystemModule/Private/AssetSystem/AssetCache.cpp

@@ -26,6 +26,8 @@ namespace Volt
 
 	AssetCache::~AssetCache()
 	{
+		ValidateAllocatorEmpty();
+
 		VT_ENSURE_MSG(m_hashTable.IsEmpty(), "Cache should have been cleared before destruction!");
 	}
 
@@ -167,4 +169,12 @@ namespace Volt
 	{
 		m_hashTable.Reserve(AssetRegistry::GetNumMaxAssets());
 	}
+
+	void AssetCache::ValidateAllocatorEmpty()
+	{
+		for (auto it = ContainerAllocator::Iterator(m_allocator); it; ++it)
+		{
+			VT_LOG(Error, "Asset {} has not been destroy properly!", it->asset->GetAssetName());
+		}
+	}
 }

Engine/Source/AssetSystemModule/Private/AssetSystem/AssetManager.cpp

@@ -37,7 +37,7 @@ namespace Volt
 
 	AssetManager::~AssetManager()
 	{
-		RunGarbageCollection(0, true);
+		CollectGarbageOnShutdown();
 		m_assetCache.Clear();
 	}
 
@@ -819,6 +819,16 @@ namespace Volt
 		}
 	}
 
+	void AssetManager::CollectGarbageOnShutdown()
+	{
+		// Since assets may hold references to other assets,
+		// we must loop until no more assets have been queued.
+		while (!m_assetEvictionQueue.Empty())
+		{
+			RunGarbageCollection(0, true);
+		}
+	}
+
 	bool AssetManager::SerializeAsset(AssetReference<Asset> asset)
 	{
 		ReadOnlyAssetMetadata assetMetadata = GetReadOnlyAssetMetadata(asset->GetAssetHandle());

Engine/Source/AssetSystemModule/Public/AssetSystem/AssetCache.h

@@ -45,8 +45,11 @@ namespace Volt
 
 	private:
 		void Initialize();
+		void ValidateAllocatorEmpty();
+
+		using ContainerAllocator = PagedAtomicArenaAllocator<Container, 1024>;
 
 		AtomicHashTable<Container*> m_hashTable;
-		PagedAtomicArenaAllocator<Container, 1024> m_allocator;
+		ContainerAllocator m_allocator;
 	};
 }

Engine/Source/AssetSystemModule/Public/AssetSystem/AssetManager.h

@@ -164,6 +164,7 @@ namespace Volt
 
 		void QueueAssetForEviction(AssetRefCounter* assetRefCounter);
 		void RunGarbageCollection(uint64_t frameIndex, bool forceCleanupAll);
+		void CollectGarbageOnShutdown();
 
 		bool DeserializeAsset(AssetReference<Asset> asset);
 

Engine/Source/CoreUtilities/Private/CoreUtilities/MemoryTracker.cpp

@@ -84,9 +84,15 @@ void MemoryTracker::OnFree(MemoryTrackerHeader* header)
 		return;
 	}
 
+	MemoryTracker& instance = Get();
+
+	if (header->memoryTagIndex >= instance.m_memoryTagCounters.size())
+	{
+		return;
+	}
+
 	g_depth++;
 
-	MemoryTracker& instance = Get();
 	instance.m_memoryTagCounters[header->memoryTagIndex].counter.fetch_sub(header->size, std::memory_order::relaxed);
 
 	g_depth--;

Engine/Source/Sandbox/Private/Sandbox/Sandbox.cpp

@@ -355,6 +355,11 @@ void Sandbox::OnDetach()
 	m_runtimeScene = nullptr;
 	m_intermediateScene = nullptr;
 
+	if (m_sceneContainer)
+	{
+		m_sceneManager->UnloadAndFreeScene(m_sceneContainer);
+	}
+
 	s_instance = nullptr;
 
 	NodeEditorHelpers::Shutdown();

Engine/Source/Sandbox/Public/Sandbox/Window/AssetBrowser/AssetBrowserConstants.h

@@ -6,6 +6,6 @@
 
 namespace AssetBrowser
 {
-	typedef PagedAtomicArenaAllocator<AssetBrowser::DirectoryItem, 256> DirectoryItemAllocator;
-	typedef PagedAtomicArenaAllocator<AssetBrowser::AssetItem, 1024> AssetItemAllocator;
+	typedef PagedAtomicArenaAllocator<AssetBrowser::DirectoryItem, 256, DefaultHeapAllocator, true> DirectoryItemAllocator;
+	typedef PagedAtomicArenaAllocator<AssetBrowser::AssetItem, 1024, DefaultHeapAllocator, true> AssetItemAllocator;
 }

Engine/Source/Volt-Renderer/Private/Volt-Renderer/RenderScene/RenderScene_Modern.cpp

@@ -38,6 +38,8 @@ namespace Volt
 
 	RenderScene_Modern::~RenderScene_Modern()
 	{
+		RunGarbageCollection();
+
 		DestroyBuffers();
 	}
 

Engine/Source/Volt-Scene/Private/Volt-Scene/SceneManager.cpp

@@ -6,6 +6,7 @@
 #include <Volt-Renderer/SceneRenderer/ISceneRenderer.h>
 
 #include <AssetSystem/AssetManager.h>
+#include <AssetSystem/AssetManagerSubSystem.h>
 
 VT_DECLARE_LOG_CATEGORY(LogSceneManager, LogVerbosity::Trace);
 VT_DEFINE_LOG_CATEGORY(LogSceneManager);
@@ -80,7 +81,7 @@ namespace Volt
 
 	void SceneManager::GetSubSystemDependencies(SubSystemDependencyList& outDependencies)
 	{
-
+		outDependencies.AddDependency<AssetManagerSubSystem>();
 	}
 
 	SceneContainer::SceneContainer(AssetReference<Scene> scene)