Optimize textures/buffers uploading on Vulkan with page allocator

Source/Engine/GraphicsDevice/DirectX/DX12/GPUDeviceDX12.h

@@ -8,6 +8,7 @@
 #include "Engine/Graphics/GPUResource.h"
 #include "../IncludeDirectXHeaders.h"
 #include "ResourceOwnerDX12.h"
+#include "UploadBufferDX12.h"
 #include "QueryHeapDX12.h"
 #include "DescriptorHeapDX12.h"
 
@@ -26,7 +27,6 @@ class Engine;
 class WindowsWindow;
 class GPUContextDX12;
 class GPUSwapChainDX12;
-class UploadBufferDX12;
 class CommandQueueDX12;
 class CommandSignatureDX12;
 
@@ -70,11 +70,10 @@ public:
     ~GPUDeviceDX12();
 
 public:
-
     /// <summary>
-    /// Upload buffer for general purpose
+    /// Data uploading utility via pages.
     /// </summary>
-    UploadBufferDX12* UploadBuffer;
+    UploadBufferDX12 UploadBuffer;
 
     /// <summary>
     /// The timestamp queries heap.