protected override void OnInitializePhysics()
        {
            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new AxisSweep3(new Vector3(-10000, -10000, -10000), new Vector3(10000, 10000, 10000));
            Solver = new SequentialImpulseConstraintSolver();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);
            World.Gravity = new Vector3(0, -10, 0);

            //World.DispatchInfo.UseConvexConservativeDistanceUtil = true;
            //World.DispatchInfo.ConvexConservativeDistanceThreshold = 0.01f;

            // Setup a big ground box
            CollisionShape groundShape = new BoxShape(100, 10, 100);
            CollisionShapes.Add(groundShape);
            Matrix groundTransform = Matrix.Translation(0, -10, 0);

            RigidBody ground = LocalCreateRigidBody(0, groundTransform, groundShape);
            ground.UserObject = "Ground";

            // Spawn one ragdoll
            SpawnRagdoll(new Vector3(1, 0.5f, 0));
            SpawnRagdoll(new Vector3(-1, 0.5f, 0));
        }

        protected override void OnInitializePhysics()
        {
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new DbvtBroadphase();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, null, CollisionConf);
            World.Gravity = new Vector3(0, -10, 0);

            // ground
            CollisionShape groundShape = new BoxShape(50, 1, 50);
            CollisionShapes.Add(groundShape);
            CollisionObject ground = LocalCreateRigidBody(0, Matrix.Identity, groundShape);
            ground.UserObject = "Ground";

            // Objects
            //colShape = new BoxShape(1);
            Vector3[] points0 = {
                new Vector3(1, 0, 0), new Vector3(0, 1, 0), new Vector3(0, 0, 1)
            };
            Vector3[] points1 = {
                new Vector3(1, 0, 0), new Vector3(0, 1, 0), new Vector3(0, 0, 1), new Vector3(0,0,-1), new Vector3(-1,-1,0)
            };
            colShape0 = new ConvexHullShape(points0);
            colShape1 = new ConvexHullShape(points1);
            CollisionShapes.Add(colShape0);
            CollisionShapes.Add(colShape1);

            /*body2 =*/ LocalCreateRigidBody(0, body2Position, colShape1);

            rotBody = LocalCreateRigidBody(0, rotBodyPosition, colShape0);
            rotBody.CollisionFlags |= CollisionFlags.KinematicObject;
            rotBody.ActivationState = ActivationState.DisableDeactivation;
        }

        protected override void OnInitializePhysics()
        {
            BoxShape boxA = new BoxShape(new Vector3(1, 1, 1));
            boxA.Margin = 0;

            BoxShape boxB = new BoxShape(new Vector3(0.5f, 0.5f, 0.5f));
            boxB.Margin = 0;

            objects[0] = new CollisionObject();
            objects[1] = new CollisionObject();

            objects[0].CollisionShape = boxA;
            objects[1].CollisionShape = boxB;

            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new AxisSweep3(new Vector3(-1000, -1000, -1000), new Vector3(1000, 1000, 1000));

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, null, CollisionConf);
            World.Gravity = new Vector3(0, -10, 0);
            IsDebugDrawEnabled = true;

            //World.AddCollisionObject(objects[0]);
            World.AddCollisionObject(objects[1]);

            Quaternion rotA = new Quaternion(0.739f, -0.204f, 0.587f, 0.257f);
            rotA.Normalize();

            objects[0].WorldTransform = Matrix.RotationQuaternion(rotA) * Matrix.Translation(0, 3, 0);
            objects[1].WorldTransform = Matrix.Translation(0, 4.248f, 0);
        }

        protected override void OnInitializePhysics()
        {
            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Vector3 worldAabbMin = new Vector3(-10000, -10000, -10000);
            Vector3 worldAabbMax = new Vector3(10000, 10000, 10000);
            Broadphase = new AxisSweep3(worldAabbMin, worldAabbMax);

            Solver = new SequentialImpulseConstraintSolver();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);
            World.Gravity = new Vector3(0, -10, 0);
            World.SetInternalTickCallback(MotorPreTickCallback, this, true);

            // create the ground
            CollisionShape groundShape = new BoxShape(200, 10, 200);
            CollisionShapes.Add(groundShape);
            CollisionObject ground = LocalCreateRigidBody(0, Matrix.Translation(0, -10, 0), groundShape);
            ground.UserObject = "Ground";

            fCyclePeriod = 2000.0f;
            fMuscleStrength = 0.5f;
            m_Time = 0;

            SpawnTestRig(new Vector3(1, 0.5f, 0), false);
            SpawnTestRig(new Vector3(-2, 0.5f, 0), true);
        }

        /*
        void MyContactCallback(object sender, ContactAddedEventArgs e)
        {
            if (e.CollisionObject0Wrapper.CollisionObject.CollisionShape.ShapeType == BroadphaseNativeType.CompoundShape)
            {
                CompoundShape compound = e.CollisionObject0Wrapper.CollisionObject.CollisionShape as CompoundShape;
                CollisionShape childShape = compound.GetChildShape(e.Index0);
            }

            if (e.CollisionObject1Wrapper.CollisionObject.CollisionShape.ShapeType == BroadphaseNativeType.CompoundShape)
            {
                CompoundShape compound = e.CollisionObject1Wrapper.CollisionObject.CollisionShape as CompoundShape;
                CollisionShape childShape = compound.GetChildShape(e.Index1);
            }

            e.IsContactModified = true;
        }
        */
        public void SetupEmptyDynamicsWorld()
        {
            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            CompoundCollisionAlgorithm.CompoundChildShapePairCallback = MyCompoundChildShapeCallback;

            convexDecompositionObjectOffset = new Vector3(10, 0, 0);

            Broadphase = new AxisSweep3(new Vector3(-10000, -10000, -10000), new Vector3(10000, 10000, 10000));
            //Broadphase = new SimpleBroadphase();

            Solver = new SequentialImpulseConstraintSolver();
            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);

            // create the ground
            CollisionShape groundShape = new BoxShape(30, 2, 30);
            CollisionShapes.Add(groundShape);
            CollisionObject ground = LocalCreateRigidBody(0, Matrix.Translation(0, -4.5f, 0), groundShape);
            ground.UserObject = "Ground";

            // create a few dynamic rigidbodies
            float mass = 1.0f;

            CollisionShape colShape = new BoxShape(1);
            CollisionShapes.Add(colShape);
            Vector3 localInertia = colShape.CalculateLocalInertia(mass);
        }

        protected override void OnInitializePhysics()
        {
            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new DbvtBroadphase();
            Solver = new SequentialImpulseConstraintSolver();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);
            World.Gravity = Freelook.Up * -10.0f;

            BspLoader bspLoader = new BspLoader();
            string[] args = Environment.GetCommandLineArgs();
            if (args.Length == 1)
            {
                bspLoader.LoadBspFile("data/BspDemo.bsp");
            }
            else
            {
                bspLoader.LoadBspFile(args[1]);
            }
            BspConverter bsp2Bullet = new BspToBulletConverter(this);
            bsp2Bullet.ConvertBsp(bspLoader, 0.1f);
        }

        public Physics()
        {
            // collision configuration contains default setup for memory, collision setup
            collisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(collisionConf);

            Broadphase = new DbvtBroadphase();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, null, collisionConf);
            World.Gravity = new Vector3(0, -10, 0);

            CollisionShapes = new List<CollisionShape>();

            // create the ground
            CollisionShape groundShape = new BoxShape(50, 1, 50);
            CollisionShapes.Add(groundShape);
            CollisionObject ground = LocalCreateRigidBody(0, Matrix.Identity, groundShape);
            ground.UserObject = "Ground";

            // create a few dynamic rigidbodies
            float mass = 1.0f;

            CollisionShape colShape = new BoxShape(1);
            CollisionShapes.Add(colShape);
            Vector3 localInertia = colShape.CalculateLocalInertia(mass);

            float start_x = StartPosX - ArraySizeX / 2;
            float start_y = StartPosY;
            float start_z = StartPosZ - ArraySizeZ / 2;

            int k, i, j;
            for (k = 0; k < ArraySizeY; k++)
            {
                for (i = 0; i < ArraySizeX; i++)
                {
                    for (j = 0; j < ArraySizeZ; j++)
                    {
                        Matrix startTransform = Matrix.CreateTranslation(
                            new Vector3(
                                2*i + start_x,
                                2*k + start_y,
                                2*j + start_z
                                )
                            );

                        // using motionstate is recommended, it provides interpolation capabilities
                        // and only synchronizes 'active' objects
                        DefaultMotionState myMotionState = new DefaultMotionState(startTransform);
                        RigidBodyConstructionInfo rbInfo =
                            new RigidBodyConstructionInfo(mass, myMotionState, colShape, localInertia);
                        RigidBody body = new RigidBody(rbInfo);

                        // make it drop from a height
                        body.Translate(new Vector3(0, 20, 0));

                        World.AddRigidBody(body);
                    }
                }
            }
        }

 void DispatcherNearCallback(BroadphasePair collisionPair, CollisionDispatcher dispatcher,
     DispatcherInfo dispatchInfo)
 {
     //AddToDisposeQueue(dispatchInfo.DebugDraw);
     TestManifoldPoints();
     //Console.WriteLine("DispatcherNearCallback");
 }

        protected override void OnInitializePhysics()
        {
            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new DbvtBroadphase();
            Solver = new SequentialImpulseConstraintSolver();

            World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);
            World.Gravity = Freelook.Up * -10.0f;

            BspLoader bspLoader = new BspLoader();
            //string[] args = Environment.GetCommandLineArgs();
            //if (args.Length == 1)
            //{
            UnityEngine.TextAsset bytes = (UnityEngine.TextAsset)UnityEngine.Resources.Load("BspDemo");
            System.IO.Stream byteStream = new System.IO.MemoryStream(bytes.bytes);
            bspLoader.LoadBspFile(byteStream);
            //}
            //else
            //{
            //    bspLoader.LoadBspFile(args[1]);
            //}
            BspConverter bsp2Bullet = new BspToBulletConverter(this);
            bsp2Bullet.ConvertBsp(bspLoader, 0.1f);
        }

        public void SetUp()
        {
            conf = new DefaultCollisionConfiguration();
            dispatcher = new CollisionDispatcher(conf);
            broadphase = new AxisSweep3(new Vector3(-1000, -1000, -1000), new Vector3(1000, 1000, 1000));
            world = new DiscreteDynamicsWorld(dispatcher, broadphase, null, conf);

            // Initialize TriangleIndexVertexArray with float array
            indexVertexArray = new TriangleIndexVertexArray(TorusMesh.Indices, TorusMesh.Vertices);
            gImpactMeshShape = new GImpactMeshShape(indexVertexArray);
            gImpactMeshShape.CalculateLocalInertia(1.0f);
            gImpactMesh = CreateBody(1.0f, gImpactMeshShape, Vector3.Zero);


            // Initialize TriangleIndexVertexArray with Vector3 array
            Vector3[] torusVertices = new Vector3[TorusMesh.Vertices.Length / 3];
            for (int i = 0; i < torusVertices.Length; i++)
            {
                torusVertices[i] = new Vector3(
                    TorusMesh.Vertices[i * 3],
                    TorusMesh.Vertices[i * 3 + 1],
                    TorusMesh.Vertices[i * 3 + 2]);
            }
            indexVertexArray2 = new TriangleIndexVertexArray(TorusMesh.Indices, torusVertices);
            triangleMeshShape = new BvhTriangleMeshShape(indexVertexArray2, true);
            // CalculateLocalInertia must fail for static shapes (shapes based on TriangleMeshShape)
            //triangleMeshShape.CalculateLocalInertia(1.0f);
            triangleMesh = CreateBody(0.0f, triangleMeshShape, Vector3.Zero);
        }

        internal DynamicWorldImp()
        {
            //Debug.WriteLine("DynamicWorldImp");

            //Default
            // collision configuration contains default setup for memory, collision setup
            BtCollisionConf = new DefaultCollisionConfiguration();
            BtDispatcher = new CollisionDispatcher(BtCollisionConf);
            BtBroadphase = new DbvtBroadphase();
            BtSolver = new SequentialImpulseConstraintSolver();
               // BtCollisionShapes = new AlignedCollisionShapeArray();

            BtWorld = new DiscreteDynamicsWorld(BtDispatcher, BtBroadphase, BtSolver, BtCollisionConf)
            {
                Gravity = new Vector3(0, -9.81f, 0)
            };

            BtWorld.SolverInfo.NumIterations = 5;

            BtWorld.PerformDiscreteCollisionDetection();

            //GImpactCollisionAlgorithm.RegisterAlgorithm(BtDispatcher);
               // BtWorld.SetInternalTickCallback(MyTickCallBack);
            //BtWorld.SetInternalTickCallback(TickTack);

            //ManifoldPoint.ContactAdded += OnContactAdded;
            //PersistentManifold.ContactDestroyed += OnContactDestroyed;
            //PersistentManifold.ContactProcessed += OnContactProcessed;
        }

 void SetupEmptyDynamicsWorld()
 {
     CollisionConf = new DefaultCollisionConfiguration();
     Dispatcher = new CollisionDispatcher(CollisionConf);
     Broadphase = new DbvtBroadphase();
     Solver = new SequentialImpulseConstraintSolver();
     World = new DiscreteDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf);
     World.Gravity = new Vector3(0, -10, 0);
 }

        public Physics()
        {
            CollisionConfiguration config = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(config);
            World = new DiscreteDynamicsWorld(Dispatcher, new DbvtBroadphase(), null, config);
            World.Gravity = new Vector3(0.0f, -9.81f, 0.0f);

            Props = new List<Prop>();
        }

		public void Setup(Vector3Df gravity)
		{
			bulletCollisionConfiguration = new DefaultCollisionConfiguration();
			bulletCollisionDispatcher = new CollisionDispatcher(bulletCollisionConfiguration);
			bulletBroadphase = new DbvtBroadphase();

			bulletWorld = new DiscreteDynamicsWorld(bulletCollisionDispatcher, bulletBroadphase, null, bulletCollisionConfiguration);
			bulletWorld.Gravity = new Vector3(gravity.X, gravity.Y, gravity.Z);
		}

        public Physics()
        {
            CLStuff.InitCL();

            cloths = new Cloth[numFlags];
            for (int flagIndex = 0; flagIndex < numFlags; ++flagIndex)
            {
                cloths[flagIndex] = new Cloth();
                cloths[flagIndex].CreateBuffers(clothWidth, clothHeight);
            }

            gSolver = new OpenCLSoftBodySolver(CLStuff.commandQueue, CLStuff.cxMainContext);
            softBodyOutput = new SoftBodySolverOutputCLToCpu();

            // collision configuration contains default setup for memory, collision setup
            CollisionConf = new SoftBodyRigidBodyCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(CollisionConf);

            Broadphase = new DbvtBroadphase();
            Solver = new SequentialImpulseConstraintSolver();

            World = new SoftRigidDynamicsWorld(Dispatcher, Broadphase, Solver, CollisionConf, gSolver);
            World.Gravity = new Vector3(0, -10, 0);

            // create the ground
            CollisionShape groundShape = new BoxShape(50, 50, 50);
            CollisionShapes.Add(groundShape);
            CollisionObject ground = LocalCreateRigidBody(0, Matrix.Translation(0, -60, 0), groundShape);
            ground.UserObject = "Ground";

            SoftWorld.WorldInfo.AirDensity = 1.2f;
            SoftWorld.WorldInfo.WaterDensity = 0;
            SoftWorld.WorldInfo.WaterOffset = 0;
            SoftWorld.WorldInfo.WaterNormal = Vector3.Zero;
            SoftWorld.WorldInfo.Gravity = new Vector3(0, -10, 0);

            CreateFlag(clothWidth, clothHeight, out flags);

            // Create output buffer descriptions for ecah flag
            // These describe where the simulation should send output data to
            for (int flagIndex = 0; flagIndex < flags.Count; ++flagIndex)
            {
                // flags[flagIndex].WindVelocity = new Vector3(0, 0, 15.0f);

                // In this case we have a DX11 output buffer with a vertex at index 0, 8, 16 and so on as well as a normal at 3, 11, 19 etc.
                // Copies will be performed GPU-side directly into the output buffer

                CpuVertexBufferDescriptor vertexBufferDescriptor = new CpuVertexBufferDescriptor(cloths[flagIndex].CpuBuffer, 0, 8, 3, 8);
                cloths[flagIndex].VertexBufferDescriptor = vertexBufferDescriptor;
            }

            gSolver.Optimize(SoftWorld.SoftBodyArray);

            World.StepSimulation(1.0f / 60.0f, 0);
        }

        public BulletSharpPhysicsComponent(Game game, BulletSharpPhysics.CollisionConfiguration collisionConf, BulletSharpPhysics.ConstraintSolver solver, Vector3 gravity)
            : base(game)
        {
            BulletSharpPhysics.CollisionDispatcher Dispatcher = new BulletSharpPhysics.CollisionDispatcher(collisionConf);

            World = new BulletSharpPhysics.DiscreteDynamicsWorld(Dispatcher, new BulletSharpPhysics.DbvtBroadphase(), solver, collisionConf);
            //World = new BulletSharpPhysics.DiscreteDynamicsWorld(Dispatcher, new BulletSharpPhysics.AxisSweep3(new Vector3(-1000),new Vector3(1000),16384), solver, collisionConf);
            World.Gravity = gravity;

       
        }

 public override void LoadContent()
 {
     base.LoadContent();
     _collisionConfiguration = new DefaultCollisionConfiguration();
     _collisionDispatcher = new CollisionDispatcher(_collisionConfiguration);
     _broadphaseInterface = new DbvtBroadphase();
     World = new DiscreteDynamicsWorld(_collisionDispatcher, _broadphaseInterface, null, _collisionConfiguration);
     World.Gravity = new Vector3(0, 9.8f, 0);
     _worldSyncEvent = new AutoResetEvent(false);
     _worldUpdateTask = new Task(UpdateWorld);
 }

        public override void Run()
        {
            var conf = new DefaultCollisionConfiguration();
            var dispatcher = new CollisionDispatcher(conf);
            var broadphase = new AxisSweep3(new Vector3(-1000, -1000, -1000), new Vector3(1000, 1000, 1000));
            world = new DiscreteDynamicsWorld(dispatcher, broadphase, null, conf);

            var indexVertexArray = new TriangleIndexVertexArray(TorusMesh.Indices, TorusMesh.Vertices);
            foreach (var indexedMesh in indexVertexArray.IndexedMeshArray)
            {
                indexedMesh.ToString();
            }
            AddToDisposeQueue(indexVertexArray);

            var gImpactMesh = new GImpactMeshShape(indexVertexArray);
            Vector3 aabbMin, aabbMax;
            gImpactMesh.GetAabb(Matrix.Identity, out aabbMin, out aabbMax);
            CreateBody(1.0f, gImpactMesh, Vector3.Zero);
            AddToDisposeQueue(gImpactMesh);
            gImpactMesh = null;

            var triangleMesh = new BvhTriangleMeshShape(indexVertexArray, true);
            triangleMesh.CalculateLocalInertia(1.0f);
            triangleMesh.GetAabb(Matrix.Identity, out aabbMin, out aabbMax);
            CreateBody(1.0f, triangleMesh, Vector3.Zero);
            AddToDisposeQueue(triangleMesh);
            triangleMesh = null;

            indexVertexArray = null;

            AddToDisposeQueue(conf);
            AddToDisposeQueue(dispatcher);
            AddToDisposeQueue(broadphase);
            AddToDisposeQueue(world);

            //conf.Dispose();
            conf = null;
            //dispatcher.Dispose();
            dispatcher = null;
            //broadphase.Dispose();
            broadphase = null;
            for (int i = 0; i < 600; i++)
            {
                world.StepSimulation(1.0f / 60.0f);
            }
            world.Dispose();
            world = null;

            ForceGC();
            TestWeakRefs();
            ClearRefs();
        }

        public Physics()
        {
            ActiveBodies = new List<PhysicalBody>();
            collisionConf = new DefaultCollisionConfiguration();
            dispatcher = new CollisionDispatcher(collisionConf);

            broadphase = new DbvtBroadphase();
            var w = new MultiBodyDynamicsWorld(dispatcher, broadphase, new MultiBodyConstraintSolver(), collisionConf);
            w.SolverInfo.SolverMode = SolverModes.CacheFriendly;
            w.SolverInfo.Restitution = 0;
            w.Gravity = new Vector3(0, -9.81f, 0);
            World = w;
        }

        public BulletPhysicWorld(Vector3 gravity)
        {
            collisionConf = new DefaultCollisionConfiguration();
            Dispatcher = new CollisionDispatcher(collisionConf);
            Broadphase = new DbvtBroadphase();
            constraintSolver = new SequentialImpulseConstraintSolver();

            objs = new List<IPhysicObject>();
            ctns = new List<IPhysicConstraint>();

            world = new DiscreteDynamicsWorld(Dispatcher, Broadphase ,constraintSolver, collisionConf);
            world.Gravity = gravity;            
        }