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+/* Copyright (c) 2016, NVIDIA CORPORATION.  All rights reserved.
+* NVIDIA CORPORATION and its licensors retain all intellectual property
+* and proprietary rights in and to this software, related documentation
+* and any modifications thereto.  Any use, reproduction, disclosure or
+* distribution of this software and related documentation without an express
+* license agreement from NVIDIA CORPORATION is strictly prohibited. */
+
+#ifndef NV_CO_DX12_COUNTER_FENCE_H
+#define NV_CO_DX12_COUNTER_FENCE_H
+
+#include <NvResult.h>
+
+#define NOMINMAX
+#include <d3d12.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <assert.h>
+#include <wrl.h>
+
+using namespace Microsoft::WRL;
+
+/** \addtogroup common
+@{
+*/
+
+namespace nvidia {
+namespace Common { 
+
+/*! \brief A class to simplify using Dx12 fences. 
+
+A fence is a mechanism to track GPU work. This is achieved by having a counter that the CPU holds 
+called the current value. Calling nextSignal will increase the CPU counter, and add a fence 
+with that value to the commandQueue. When the GPU has completed all the work before the fence it will 
+update the completed value. This is typically used when 
+the CPU needs to know the GPU has finished some piece of work has completed. To do this the CPU
+can check the completed value, and when it is greater or equal to the value returned by nextSignal the 
+CPU will know that all the work prior to when the nextSignal was added to the queue will have completed. 
+
+NOTE! This cannot be used across threads, as for amongst other reasons SetEventOnCompletion 
+only works with a single value.
+
+Signal on the CommandQueue updates the fence on the GPU side. Signal on the fence object changes 
+the value on the CPU side (not used here).
+
+Useful article describing how Dx12 synchronization works:
+https://msdn.microsoft.com/en-us/library/windows/desktop/dn899217%28v=vs.85%29.aspx
+*/
+class Dx12CounterFence
+{
+	//NV_CO_DECLARE_CLASS_BASE(Dx12CounterFence);
+public:
+		/// Must be called before used
+	int init(ID3D12Device* device, uint64_t initialValue = 0);
+		/// Increases the counter, signals the queue and waits for the signal to be hit
+	void nextSignalAndWait(ID3D12CommandQueue* queue);
+		/// Signals with next counter value. Returns the value the signal was called on
+	uint64_t nextSignal(ID3D12CommandQueue* commandQueue);
+		/// Get the current value
+	inline uint64_t getCurrentValue() const { return m_currentValue; }
+		/// Get the completed value
+	inline uint64_t getCompletedValue() const { return m_fence->GetCompletedValue(); }
+
+		/// Waits for the the specified value 
+	void waitUntilCompleted(uint64_t completedValue);
+
+		/// Ctor
+	Dx12CounterFence():m_event(nullptr), m_currentValue(0) {}
+		/// Dtor
+	~Dx12CounterFence();
+
+	protected:
+	HANDLE m_event;
+	ComPtr<ID3D12Fence> m_fence;
+	uint64_t m_currentValue;
+};
+
+} // namespace Common
+} // namespace nvidia
+
+/** @} */
+
+#endif // NV_CO_DX12_COUNTER_FENCE_H