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diff --git a/PhysX_3.4/Source/Common/src/CmReaderWriterLock.h b/PhysX_3.4/Source/Common/src/CmReaderWriterLock.h
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+// This code contains NVIDIA Confidential Information and is disclosed to you
+// under a form of NVIDIA software license agreement provided separately to you.
+//
+// Notice
+// NVIDIA Corporation and its licensors retain all intellectual property and
+// proprietary rights in and to this software and 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.
+//
+// ALL NVIDIA DESIGN SPECIFICATIONS, CODE ARE PROVIDED "AS IS.". NVIDIA MAKES
+// NO WARRANTIES, EXPRESSED, IMPLIED, STATUTORY, OR OTHERWISE WITH RESPECT TO
+// THE MATERIALS, AND EXPRESSLY DISCLAIMS ALL IMPLIED WARRANTIES OF NONINFRINGEMENT,
+// MERCHANTABILITY, AND FITNESS FOR A PARTICULAR PURPOSE.
+//
+// Information and code furnished is believed to be accurate and reliable.
+// However, NVIDIA Corporation assumes no responsibility for the consequences of use of such
+// information or for any infringement of patents or other rights of third parties that may
+// result from its use. No license is granted by implication or otherwise under any patent
+// or patent rights of NVIDIA Corporation. Details are subject to change without notice.
+// This code supersedes and replaces all information previously supplied.
+// NVIDIA Corporation products are not authorized for use as critical
+// components in life support devices or systems without express written approval of
+// NVIDIA Corporation.
+//
+// Copyright (c) 2008-2016 NVIDIA Corporation. All rights reserved.
+// Copyright (c) 2004-2008 AGEIA Technologies, Inc. All rights reserved.
+// Copyright (c) 2001-2004 NovodeX AG. All rights reserved.  
+
+
+#ifndef PX_PHYSICS_COMMON_READERWRITERLOCK
+#define PX_PHYSICS_COMMON_READERWRITERLOCK
+
+//#define PX_RAYCAST_READWRITE_LOCK
+
+/*
+Implements a full reader writer lock, i.e. multiple readers or a single writer.
+
+Below is an implementation using just a mutex for non win32 platforms.
+
+Disable the full reader/writer lock by default. Using the full reader writer lock
+results in better performance when a lot of parallel raycasts are performed but is
+more costly when only a few are performed and slows down serial raycasts.
+*/
+
+namespace physx
+{
+namespace Cm
+{
+
+#ifdef PX_RAYCAST_READWRITE_LOCK
+	class ReaderWriterLock
+	{
+	public:
+
+		PX_INLINE ReaderWriterLock()
+		{
+			hReaderEvent=CreateEvent(NULL,TRUE,FALSE,NULL);
+			PX_ASSERT(hReaderEvent!=NULL);
+
+			hMutex = CreateEvent(NULL,FALSE,TRUE,NULL);
+			PX_ASSERT(hMutex!=NULL);
+
+			InitializeCriticalSection(&writerMutex);
+			counter = -1;
+			recursionCounter=0;
+		}
+		PX_INLINE ~ReaderWriterLock()
+		{
+			if(hReaderEvent!=NULL)
+				CloseHandle(hReaderEvent);
+			if(hMutex!=NULL)
+				CloseHandle(hMutex);
+			DeleteCriticalSection(&writerMutex);
+		}
+
+		PX_INLINE void lockReader()
+		{
+			if(InterlockedIncrement(&counter) == 0)
+			{
+				WaitForSingleObject(hMutex, INFINITE);
+				SetEvent(hReaderEvent);
+			}
+
+			WaitForSingleObject(hReaderEvent,INFINITE);
+		}
+
+		PX_INLINE void lockWriter()
+		{
+			EnterCriticalSection(&writerMutex);
+
+			//we may already have the global mutex(really an event so we have to handle recursion ourselves)
+			recursionCounter++;
+			if(recursionCounter==1)
+				WaitForSingleObject(hMutex, INFINITE);
+		}
+		PX_INLINE void unlockReader()
+		{
+			if(InterlockedDecrement(&counter) < 0)
+			{
+				ResetEvent(hReaderEvent);
+				SetEvent(hMutex);
+			}
+		}
+		PX_INLINE void unlockWriter()
+		{
+			recursionCounter--;
+			if(recursionCounter==0)
+				SetEvent(hMutex);
+
+			LeaveCriticalSection(&writerMutex);
+		}
+
+	private:
+
+		HANDLE hReaderEvent;
+		HANDLE hMutex;
+		CRITICAL_SECTION writerMutex;
+		LONG counter;//count the number of readers in the lock.
+		LONG recursionCounter;//handle recursive writer locking
+	};
+#else
+	/*
+	TODO: implement proper reader writer lock for other platforms, eg cell os has a native reader writer lock.
+	*/
+
+	class ReaderWriterLock
+	{
+		PX_NOCOPY(ReaderWriterLock)
+	public:
+
+		PX_INLINE void lockReader()
+		{
+			//lock.lock();
+			lock.lockReader();
+		}
+		PX_INLINE void lockWriter()
+		{
+			//lock.lock();
+			lock.lockWriter();
+		}
+		PX_INLINE void unlockReader()
+		{
+			//lock.unlock();
+			lock.unlockReader();
+		}
+		PX_INLINE void unlockWriter()
+		{
+			//lock.unlock();
+			lock.unlockWriter();
+		}
+
+	private:
+
+		//Ps::Mutex lock;
+
+		Ps::AtomicRwLock lock;
+	};
+#endif
+
+	class TakeReaderLock
+	{
+	public:
+
+		TakeReaderLock(ReaderWriterLock &l) : lock(l)
+		{
+			lock.lockReader();
+		}
+		~TakeReaderLock()
+		{
+			lock.unlockReader();
+		}
+
+	private:
+		TakeReaderLock& operator=(const TakeReaderLock&);
+		ReaderWriterLock &lock;
+	};
+
+	class TakeWriterLock
+	{
+	public:
+
+		TakeWriterLock(ReaderWriterLock &l) : lock(l)
+		{
+			lock.lockWriter();
+		}
+		~TakeWriterLock()
+		{
+			lock.unlockWriter();
+		}
+
+	private:
+		TakeWriterLock& operator=(const TakeWriterLock&);
+		ReaderWriterLock &lock;
+	};
+
+
+} // namespace Cm
+
+}
+
+#endif