Add the GPU rigid body pipeline from https://github.com/erwincoumans/experiments as a Bullet 3.x preview for Bullet 2.80

Extras/RigidBodyGpuPipeline/opencl/gpu_rigidbody_pipeline/btGpuNarrowPhaseAndSolver.h

@@ -0,0 +1,72 @@
+/*
+Copyright (c) 2012 Advanced Micro Devices, Inc.  
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+//Originally written by Erwin Coumans
+
+#ifndef GPU_NARROWPHASE_SOLVER_H
+#define GPU_NARROWPHASE_SOLVER_H
+
+
+
+//#define MAX_CONVEX_BODIES_CL 8*1024
+#define MAX_CONVEX_BODIES_CL 128*1024
+#define MAX_PAIRS_PER_BODY_CL 16
+#define MAX_CONVEX_SHAPES_CL 8192
+#define MAX_BROADPHASE_COLLISION_CL (MAX_CONVEX_BODIES_CL*MAX_PAIRS_PER_BODY_CL)
+
+/*
+#define MAX_CONVEX_BODIES_CL 1024
+#define MAX_PAIRS_PER_BODY_CL 32
+#define MAX_CONVEX_SHAPES_CL 8192
+#define MAX_BROADPHASE_COLLISION_CL (MAX_CONVEX_BODIES_CL*MAX_PAIRS_PER_BODY_CL)
+*/
+
+namespace adl
+{
+	struct DeviceCL;
+};
+
+
+struct	CustomDispatchData;
+
+#include "../basic_initialize/btOpenCLInclude.h"
+
+
+class btGpuNarrowphaseAndSolver
+{
+protected:
+
+	CustomDispatchData*	m_internalData;
+	int m_acceleratedCompanionShapeIndex;
+	int m_planeBodyIndex;
+
+public:
+	btGpuNarrowphaseAndSolver(adl::DeviceCL* deviceCL);
+
+	virtual ~btGpuNarrowphaseAndSolver(void);
+
+	int registerShape(class ConvexHeightField* convexShape);
+	int registerRigidBody(int shapeIndex, float mass, const float* position, const float* orientation, bool writeToGpu = true);
+	void	writeAllBodiesToGpu();
+	
+	//btBroadphasePair* GetPair(btBroadphasePairArray& pairArray, int idxBodyA, int idxBodyB);
+
+	virtual void computeContactsAndSolver(cl_mem broadphasePairs, int numBroadphasePairs);
+
+	cl_mem	getBodiesGpu();
+
+	cl_mem	getBodyInertiasGpu();
+
+};
+
+#endif //GPU_NARROWPHASE_SOLVER_H