protected override void OnInitializePhysics()
        {
            ManifoldPoint.ContactAdded += MyContactCallback;

            SetupEmptyDynamicsWorld();

            CompoundCollisionAlgorithm.CompoundChildShapePairCallback = MyCompoundChildShapeCallback;
            convexDecompositionObjectOffset = new Vector3(10, 0, 0);

            // Load wavefront file
            var wo = new WavefrontObj();
            int tcount = wo.LoadObj("data/file.obj");
            if (tcount == 0)
            {
                return;
            }

            // Convert file data to TriangleMesh
            var trimesh = new TriangleMesh();
            trimeshes.Add(trimesh);

            Vector3 localScaling = new Vector3(6, 6, 6);
            List<int> indices = wo.Indices;
            List<Vector3> vertices = wo.Vertices;

            int i;
            for (i = 0; i < tcount; i++)
            {
                int index0 = indices[i * 3];
                int index1 = indices[i * 3 + 1];
                int index2 = indices[i * 3 + 2];

                Vector3 vertex0 = vertices[index0] * localScaling;
                Vector3 vertex1 = vertices[index1] * localScaling;
                Vector3 vertex2 = vertices[index2] * localScaling;

                trimesh.AddTriangleRef(ref vertex0, ref vertex1, ref vertex2);
            }

            // Create a hull approximation
            ConvexHullShape convexShape;
            using (var tmpConvexShape = new ConvexTriangleMeshShape(trimesh))
            {
                using (var hull = new ShapeHull(tmpConvexShape))
                {
                    hull.BuildHull(tmpConvexShape.Margin);
                    convexShape = new ConvexHullShape(hull.Vertices);
                }
            }
            if (sEnableSAT)
            {
                convexShape.InitializePolyhedralFeatures();
            }
            CollisionShapes.Add(convexShape);

            // Add non-moving body to world
            float mass = 1.0f;
            LocalCreateRigidBody(mass, Matrix.Translation(0, 2, 14), convexShape);

            const bool useQuantization = true;
            var concaveShape = new BvhTriangleMeshShape(trimesh, useQuantization);
            LocalCreateRigidBody(0, Matrix.Translation(convexDecompositionObjectOffset), concaveShape);

            CollisionShapes.Add(concaveShape);

            // HACD
            var hacd = new Hacd();
            hacd.SetPoints(wo.Vertices);
            hacd.SetTriangles(wo.Indices);
            hacd.CompacityWeight = 0.1;
            hacd.VolumeWeight = 0.0;

            // Recommended HACD parameters: 2 100 false false false
            hacd.NClusters = 2;                      // minimum number of clusters
            hacd.Concavity = 100;                    // maximum concavity
            hacd.AddExtraDistPoints = false;
            hacd.AddNeighboursDistPoints = false;
            hacd.AddFacesPoints = false;
            hacd.NumVerticesPerConvexHull = 100;     // max of 100 vertices per convex-hull

            hacd.Compute();
            hacd.Save("output.wrl", false);

            // Generate convex result
            var outputFile = new FileStream("file_convex.obj", FileMode.Create, FileAccess.Write);
            var writer = new StreamWriter(outputFile);

            var convexDecomposition = new ConvexDecomposition(writer, this);
            convexDecomposition.LocalScaling = localScaling;

            for (int c = 0; c < hacd.NClusters; c++)
            {
                Vector3[] points;
                int[] triangles;
                hacd.GetCH(c, out points, out triangles);

                convexDecomposition.ConvexDecompResult(points, triangles);
            }

            // Combine convex shapes into a compound shape
            var compound = new CompoundShape();
            for (i = 0; i < convexDecomposition.convexShapes.Count; i++)
            {
                Vector3 centroid = convexDecomposition.convexCentroids[i];
                var convexShape2 = convexDecomposition.convexShapes[i];
                Matrix trans = Matrix.Translation(centroid);
                if (sEnableSAT)
                {
                    convexShape2.InitializePolyhedralFeatures();
                }
                CollisionShapes.Add(convexShape2);
                compound.AddChildShape(trans, convexShape2);

                LocalCreateRigidBody(1.0f, trans, convexShape2);
            }
            CollisionShapes.Add(compound);

            writer.Dispose();
            outputFile.Dispose();

            #if true
            mass = 10.0f;
            var body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

            convexDecompositionObjectOffset.Z = 6;
            body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

            convexDecompositionObjectOffset.Z = -6;
            body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;
            #endif
        }
        protected override void OnInitializePhysics()
        {
            ManifoldPoint.ContactAdded += MyContactCallback;

            SetupEmptyDynamicsWorld();

            WavefrontObj wo = new WavefrontObj();
            int tcount = wo.LoadObj("data/file.obj");
            if (tcount > 0)
            {
                TriangleMesh trimesh = new TriangleMesh();
                trimeshes.Add(trimesh);

                Vector3 localScaling = new Vector3(6, 6, 6);
                List<int> indices = wo.Indices;
                List<Vector3> vertices = wo.Vertices;

                int i;
                for (i = 0; i < tcount; i++)
                {
                    int index0 = indices[i * 3];
                    int index1 = indices[i * 3 + 1];
                    int index2 = indices[i * 3 + 2];

                    Vector3 vertex0 = vertices[index0] * localScaling;
                    Vector3 vertex1 = vertices[index1] * localScaling;
                    Vector3 vertex2 = vertices[index2] * localScaling;

                    trimesh.AddTriangle(vertex0, vertex1, vertex2);
                }

                ConvexShape tmpConvexShape = new ConvexTriangleMeshShape(trimesh);

                //create a hull approximation
                ShapeHull hull = new ShapeHull(tmpConvexShape);
                float margin = tmpConvexShape.Margin;
                hull.BuildHull(margin);
                tmpConvexShape.UserObject = hull;

                ConvexHullShape convexShape = new ConvexHullShape();
                foreach (Vector3 v in hull.Vertices)
                {
                    convexShape.AddPoint(v);
                }

                if (sEnableSAT)
                {
                    convexShape.InitializePolyhedralFeatures();
                }
                tmpConvexShape.Dispose();
                //hull.Dispose();

                CollisionShapes.Add(convexShape);

                float mass = 1.0f;

                LocalCreateRigidBody(mass, Matrix.Translation(0, 2, 14), convexShape);

                const bool useQuantization = true;
                CollisionShape concaveShape = new BvhTriangleMeshShape(trimesh, useQuantization);
                LocalCreateRigidBody(0, Matrix.Translation(convexDecompositionObjectOffset), concaveShape);

                CollisionShapes.Add(concaveShape);

                // Bullet Convex Decomposition

                FileStream outputFile = new FileStream("file_convex.obj", FileMode.Create, FileAccess.Write);
                StreamWriter writer = new StreamWriter(outputFile);

                DecompDesc desc = new DecompDesc
                {
                    mVertices = wo.Vertices.ToArray(),
                    mTcount = tcount,
                    mIndices = wo.Indices.ToArray(),
                    mDepth = 5,
                    mCpercent = 5,
                    mPpercent = 15,
                    mMaxVertices = 16,
                    mSkinWidth = 0.0f
                };

                MyConvexDecomposition convexDecomposition = new MyConvexDecomposition(writer, this);
                desc.mCallback = convexDecomposition;

                // HACD

                Hacd myHACD = new Hacd();
                myHACD.SetPoints(wo.Vertices);
                myHACD.SetTriangles(wo.Indices);
                myHACD.CompacityWeight = 0.1;
                myHACD.VolumeWeight = 0.0;

                // HACD parameters
                // Recommended parameters: 2 100 0 0 0 0
                int nClusters = 2;
                const double concavity = 100;
                //bool invert = false;
                const bool addExtraDistPoints = false;
                const bool addNeighboursDistPoints = false;
                const bool addFacesPoints = false;

                myHACD.NClusters = nClusters;                     // minimum number of clusters
                myHACD.VerticesPerConvexHull = 100;               // max of 100 vertices per convex-hull
                myHACD.Concavity = concavity;                     // maximum concavity
                myHACD.AddExtraDistPoints = addExtraDistPoints;
                myHACD.AddNeighboursDistPoints = addNeighboursDistPoints;
                myHACD.AddFacesPoints = addFacesPoints;

                myHACD.Compute();
                nClusters = myHACD.NClusters;

                myHACD.Save("output.wrl", false);

                if (true)
                {
                    CompoundShape compound = new CompoundShape();
                    CollisionShapes.Add(compound);

                    Matrix trans = Matrix.Identity;

                    for (int c = 0; c < nClusters; c++)
                    {
                        //generate convex result
                        Vector3[] points;
                        int[] triangles;
                        myHACD.GetCH(c, out points, out triangles);

                        ConvexResult r = new ConvexResult(points, triangles);
                        convexDecomposition.ConvexDecompResult(r);
                    }

                    for (i = 0; i < convexDecomposition.convexShapes.Count; i++)
                    {
                        Vector3 centroid = convexDecomposition.convexCentroids[i];
                        trans = Matrix.Translation(centroid);
                        ConvexHullShape convexShape2 = convexDecomposition.convexShapes[i] as ConvexHullShape;
                        compound.AddChildShape(trans, convexShape2);

                        RigidBody body = LocalCreateRigidBody(1.0f, trans, convexShape2);
                    }

            #if true
                    mass = 10.0f;
                    trans = Matrix.Translation(-convexDecompositionObjectOffset);
                    RigidBody body2 = LocalCreateRigidBody(mass, trans, compound);
                    body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

                    convexDecompositionObjectOffset.Z = 6;
                    trans = Matrix.Translation(-convexDecompositionObjectOffset);
                    body2 = LocalCreateRigidBody(mass, trans, compound);
                    body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

                    convexDecompositionObjectOffset.Z = -6;
                    trans = Matrix.Translation(-convexDecompositionObjectOffset);
                    body2 = LocalCreateRigidBody(mass, trans, compound);
                    body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;
            #endif
                }

                writer.Dispose();
                outputFile.Dispose();
            }
        }
        protected override void OnInitializePhysics()
        {
            ManifoldPoint.ContactAdded += MyContactCallback;

            SetupEmptyDynamicsWorld();

            //CompoundCollisionAlgorithm.CompoundChildShapePairCallback = MyCompoundChildShapeCallback;
            convexDecompositionObjectOffset = new Vector3(10, 0, 0);

            // Load wavefront file
            var wo = new WavefrontObj();
            //string filename = UnityEngine.Application.dataPath + "/BulletUnity/Examples/Scripts/BulletSharpDemos/ConvexDecompositionDemo/data/file.obj";
            UnityEngine.TextAsset bytes = (UnityEngine.TextAsset)UnityEngine.Resources.Load("file.obj");
            System.IO.Stream byteStream = new System.IO.MemoryStream(bytes.bytes);

            int tcount = wo.LoadObj(byteStream);
            if (tcount == 0)
            {
                return;
            }

            // Convert file data to TriangleMesh
            var trimesh = new TriangleMesh();
            trimeshes.Add(trimesh);

            Vector3 localScaling = new Vector3(6, 6, 6);
            List<int> indices = wo.Indices;
            List<Vector3> vertices = wo.Vertices;

            int i;
            for (i = 0; i < tcount; i++)
            {
                int index0 = indices[i * 3];
                int index1 = indices[i * 3 + 1];
                int index2 = indices[i * 3 + 2];

                Vector3 vertex0 = vertices[index0] * localScaling;
                Vector3 vertex1 = vertices[index1] * localScaling;
                Vector3 vertex2 = vertices[index2] * localScaling;

                trimesh.AddTriangleRef(ref vertex0, ref vertex1, ref vertex2);
            }

            // Create a hull approximation
            ConvexHullShape convexShape;
            using (var tmpConvexShape = new ConvexTriangleMeshShape(trimesh))
            {
                using (var hull = new ShapeHull(tmpConvexShape))
                {
                    hull.BuildHull(tmpConvexShape.Margin);
                    convexShape = new ConvexHullShape(hull.Vertices);
                }
            }
            if (sEnableSAT)
            {
                convexShape.InitializePolyhedralFeatures();
            }
            CollisionShapes.Add(convexShape);

            // Add non-moving body to world
            float mass = 1.0f;
            LocalCreateRigidBody(mass, Matrix.Translation(0, 2, 14), convexShape);

            const bool useQuantization = true;
            var concaveShape = new BvhTriangleMeshShape(trimesh, useQuantization);
            LocalCreateRigidBody(0, Matrix.Translation(convexDecompositionObjectOffset), concaveShape);

            CollisionShapes.Add(concaveShape);

            // HACD
            var hacd = new Hacd();
            hacd.SetPoints(wo.Vertices);
            hacd.SetTriangles(wo.Indices);
            hacd.CompacityWeight = 0.1;
            hacd.VolumeWeight = 0.0;

            // Recommended HACD parameters: 2 100 false false false
            hacd.NClusters = 2;                      // minimum number of clusters
            hacd.Concavity = 100;                    // maximum concavity
            hacd.AddExtraDistPoints = false;
            hacd.AddNeighboursDistPoints = false;
            hacd.AddFacesPoints = false;
            hacd.NVerticesPerCH = 100;     // max of 100 vertices per convex-hull

            hacd.Compute();
            hacd.Save("output.wrl", false);

            // Generate convex result
            var outputFile = new FileStream("file_convex.obj", FileMode.Create, FileAccess.Write);
            var writer = new StreamWriter(outputFile);

            var convexDecomposition = new ConvexDecomposition(writer, this);
            convexDecomposition.LocalScaling = localScaling;

            for (int c = 0; c < hacd.NClusters; c++)
            {
                int nVertices = hacd.GetNPointsCH(c);
                int trianglesLen = hacd.GetNTrianglesCH(c) * 3;
                double[] points = new double[nVertices * 3];
                long[] triangles = new long[trianglesLen];
                hacd.GetCH(c, points, triangles);

                if (trianglesLen == 0)
                {
                    continue;
                }

                Vector3[] verticesArray = new Vector3[nVertices];
                int vi3 = 0;
                for (int vi = 0; vi < nVertices; vi++)
                {
                    verticesArray[vi] = new Vector3(
                        (float)points[vi3], (float)points[vi3 + 1], (float)points[vi3 + 2]);
                    vi3 += 3;
                }

                int[] trianglesInt = new int[trianglesLen];
                for (int ti = 0; ti < trianglesLen; ti++)
                {
                    trianglesInt[ti] = (int)triangles[ti];
                }

                convexDecomposition.ConvexDecompResult(verticesArray, trianglesInt);
            }

            // Combine convex shapes into a compound shape
            var compound = new CompoundShape();
            for (i = 0; i < convexDecomposition.convexShapes.Count; i++)
            {
                Vector3 centroid = convexDecomposition.convexCentroids[i];
                var convexShape2 = convexDecomposition.convexShapes[i];
                Matrix trans = Matrix.Translation(centroid);
                if (sEnableSAT)
                {
                    convexShape2.InitializePolyhedralFeatures();
                }
                CollisionShapes.Add(convexShape2);
                compound.AddChildShape(trans, convexShape2);

                LocalCreateRigidBody(1.0f, trans, convexShape2);
            }
            CollisionShapes.Add(compound);

            writer.Dispose();
            outputFile.Dispose();

            #if true
            mass = 10.0f;
            var body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

            convexDecompositionObjectOffset.Z = 6;
            body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;

            convexDecompositionObjectOffset.Z = -6;
            body2 = LocalCreateRigidBody(mass, Matrix.Translation(-convexDecompositionObjectOffset), compound);
            body2.CollisionFlags |= CollisionFlags.CustomMaterialCallback;
            #endif
        }