protected override void OnInitializePhysics()
        {
            SetupEmptyDynamicsWorld();
            IsDebugDrawEnabled = true;

            CollisionShape groundShape = new BoxShape(50, 1, 50);
            //CollisionShape groundShape = new StaticPlaneShape(Vector3.UnitY, 40);
            CollisionShapes.Add(groundShape);
            RigidBody body = LocalCreateRigidBody(0, Matrix.Translation(0, -16, 0), groundShape);
            body.UserObject = "Ground";

            CollisionShape shape = new BoxShape(new Vector3(CubeHalfExtents));
            CollisionShapes.Add(shape);

            const float THETA = (float)Math.PI/4.0f;
            float L_1 = 2 - (float)Math.Tan(THETA);
            float L_2 = 1 / (float)Math.Cos(THETA);
            float RATIO = L_2/L_1;

            RigidBody bodyA;
            RigidBody bodyB;

            CollisionShape cylA = new CylinderShape(0.2f, 0.25f, 0.2f);
            CollisionShape cylB = new CylinderShape(L_1, 0.025f, L_1);
            CompoundShape cyl0 = new CompoundShape();
            cyl0.AddChildShape(Matrix.Identity, cylA);
            cyl0.AddChildShape(Matrix.Identity, cylB);

            float mass = 6.28f;
            Vector3 localInertia;
            cyl0.CalculateLocalInertia(mass, out localInertia);
            RigidBodyConstructionInfo ci = new RigidBodyConstructionInfo(mass, null, cyl0, localInertia);
            ci.StartWorldTransform = Matrix.Translation(-8, 1, -8);

            body = new RigidBody(ci); //1,0,cyl0,localInertia);
            World.AddRigidBody(body);
            body.LinearFactor = Vector3.Zero;
            body.AngularFactor = new Vector3(0, 1, 0);
            bodyA = body;

            cylA = new CylinderShape(0.2f, 0.26f, 0.2f);
            cylB = new CylinderShape(L_2, 0.025f, L_2);
            cyl0 = new CompoundShape();
            cyl0.AddChildShape(Matrix.Identity, cylA);
            cyl0.AddChildShape(Matrix.Identity, cylB);

            mass = 6.28f;
            cyl0.CalculateLocalInertia(mass, out localInertia);
            ci = new RigidBodyConstructionInfo(mass, null, cyl0, localInertia);
            Quaternion orn = Quaternion.RotationAxis(new Vector3(0, 0, 1), -THETA);
            ci.StartWorldTransform = Matrix.RotationQuaternion(orn) * Matrix.Translation(-10, 2, -8);

            body = new RigidBody(ci);//1,0,cyl0,localInertia);
            body.LinearFactor = Vector3.Zero;
            HingeConstraint hinge = new HingeConstraint(body, Vector3.Zero, new Vector3(0, 1, 0), true);
            World.AddConstraint(hinge);
            bodyB = body;
            body.AngularVelocity = new Vector3(0, 3, 0);

            World.AddRigidBody(body);

            Vector3 axisA = new Vector3(0, 1, 0);
            Vector3 axisB = new Vector3(0, 1, 0);
            orn = Quaternion.RotationAxis(new Vector3(0, 0, 1), -THETA);
            Matrix mat = Matrix.RotationQuaternion(orn);
            axisB = new Vector3(mat.M21, mat.M22, mat.M23);

            GearConstraint gear = new GearConstraint(bodyA, bodyB, axisA, axisB, RATIO);
            World.AddConstraint(gear, true);

            mass = 1.0f;

            RigidBody body0 = LocalCreateRigidBody(mass, Matrix.Translation(0, 20, 0), shape);

            RigidBody body1 = null;//LocalCreateRigidBody(mass, Matrix.Translation(2*CUBE_HALF_EXTENTS,20,0), shape);
            //RigidBody body1 = LocalCreateRigidBody(0, Matrix.Translation(2*CUBE_HALF_EXTENTS,20,0), null);
            //body1.ActivationState = ActivationState.DisableDeactivation;
            //body1.SetDamping(0.3f, 0.3f);

            Vector3 pivotInA = new Vector3(CubeHalfExtents, -CubeHalfExtents, -CubeHalfExtents);
            Vector3 axisInA = new Vector3(0, 0, 1);

            Vector3 pivotInB;
            if (body1 != null)
            {
                Matrix transform = Matrix.Invert(body1.CenterOfMassTransform) * body0.CenterOfMassTransform;
                pivotInB = Vector3.TransformCoordinate(pivotInA, transform);
            }
            else
            {
                pivotInB = pivotInA;
            }

            Vector3 axisInB;
            if (body1 != null)
            {
                Matrix transform = Matrix.Invert(body1.CenterOfMassTransform) * body1.CenterOfMassTransform;
                axisInB = Vector3.TransformCoordinate(axisInA, transform);
            }
            else
            {
                axisInB = Vector3.TransformCoordinate(axisInA, body0.CenterOfMassTransform);
            }

            #if P2P
            {
                TypedConstraint p2p = new Point2PointConstraint(body0, pivotInA);
                //TypedConstraint p2p = new Point2PointConstraint(body0, body1, pivotInA, pivotInB);
                //TypedConstraint hinge = new HingeConstraint(body0, body1, pivotInA, pivotInB, axisInA, axisInB);
                World.AddConstraint(p2p);
                p2p.DebugDrawSize = 5;
            }
            #else
            {
                hinge = new HingeConstraint(body0, pivotInA, axisInA);

                //use zero targetVelocity and a small maxMotorImpulse to simulate joint friction
                //float	targetVelocity = 0.f;
                //float	maxMotorImpulse = 0.01;
                const float targetVelocity = 1.0f;
                const float maxMotorImpulse = 1.0f;
                hinge.EnableAngularMotor(true, targetVelocity, maxMotorImpulse);
                World.AddConstraint(hinge);
                hinge.DebugDrawSize = 5;
            }
            #endif

            RigidBody pRbA1 = LocalCreateRigidBody(mass, Matrix.Translation(-20, 0, 30), shape);
            //RigidBody pRbA1 = LocalCreateRigidBody(0.0f, Matrix.Translation(-20, 0, 30), shape);
            pRbA1.ActivationState = ActivationState.DisableDeactivation;

            // add dynamic rigid body B1
            RigidBody pRbB1 = LocalCreateRigidBody(mass, Matrix.Translation(-20, 0, 30), shape);
            //RigidBody pRbB1 = LocalCreateRigidBody(0.0f, Matrix.Translation(-20, 0, 30), shape);
            pRbB1.ActivationState = ActivationState.DisableDeactivation;

            // create slider constraint between A1 and B1 and add it to world
            SliderConstraint spSlider1 = new SliderConstraint(pRbA1, pRbB1, Matrix.Identity, Matrix.Identity, true);
            //spSlider1 = new SliderConstraint(pRbA1, pRbB1, Matrix.Identity, Matrix.Identity, false);
            spSlider1.LowerLinearLimit = -15.0f;
            spSlider1.UpperLinearLimit = -5.0f;
            spSlider1.LowerLinearLimit = 5.0f;
            spSlider1.UpperLinearLimit = 15.0f;
            spSlider1.LowerLinearLimit = -10.0f;
            spSlider1.UpperLinearLimit = -10.0f;

            spSlider1.LowerAngularLimit = -(float)Math.PI / 3.0f;
            spSlider1.UpperAngularLimit = (float)Math.PI / 3.0f;

            World.AddConstraint(spSlider1, true);
            spSlider1.DebugDrawSize = 5.0f;

            //create a slider, using the generic D6 constraint
            Vector3 sliderWorldPos = new Vector3(0, 10, 0);
            Vector3 sliderAxis = Vector3.UnitX;
            const float angle = 0; //SIMD_RADS_PER_DEG * 10.f;
            Matrix trans = Matrix.RotationAxis(sliderAxis, angle) * Matrix.Translation(sliderWorldPos);
            d6body0 = LocalCreateRigidBody(mass, trans, shape);
            d6body0.ActivationState = ActivationState.DisableDeactivation;

            RigidBody fixedBody1 = LocalCreateRigidBody(0, trans, null);
            World.AddRigidBody(fixedBody1);

            Matrix frameInA = Matrix.Translation(0, 5, 0);
            Matrix frameInB = Matrix.Translation(0, 5, 0);

            //bool useLinearReferenceFrameA = false;//use fixed frame B for linear llimits
            const bool useLinearReferenceFrameA = true; //use fixed frame A for linear llimits
            spSlider6Dof = new Generic6DofConstraint(fixedBody1, d6body0, frameInA, frameInB, useLinearReferenceFrameA)
            {
                LinearLowerLimit = lowerSliderLimit,
                LinearUpperLimit = hiSliderLimit,

                //range should be small, otherwise singularities will 'explode' the constraint
                //AngularLowerLimit = new Vector3(-1.5f,0,0),
                //AngularUpperLimit = new Vector3(1.5f,0,0),
                //AngularLowerLimit = new Vector3(0,0,0),
                //AngularUpperLimit = new Vector3(0,0,0),
                AngularLowerLimit = new Vector3((float)-Math.PI, 0, 0),
                AngularUpperLimit = new Vector3(1.5f, 0, 0)
            };

            //spSlider6Dof.TranslationalLimitMotor.EnableMotor[0] = true;
            spSlider6Dof.TranslationalLimitMotor.TargetVelocity = new Vector3(-5.0f, 0, 0);
            spSlider6Dof.TranslationalLimitMotor.MaxMotorForce = new Vector3(0.1f, 0, 0);

            World.AddConstraint(spSlider6Dof);
            spSlider6Dof.DebugDrawSize = 5;

            // create a door using hinge constraint attached to the world

            CollisionShape pDoorShape = new BoxShape(2.0f, 5.0f, 0.2f);
            CollisionShapes.Add(pDoorShape);
            RigidBody pDoorBody = LocalCreateRigidBody(1.0f, Matrix.Translation(-5.0f, -2.0f, 0.0f), pDoorShape);
            pDoorBody.ActivationState = ActivationState.DisableDeactivation;
            Vector3 btPivotA = new Vector3(10.0f + 2.1f, -2.0f, 0.0f); // right next to the door slightly outside
            Vector3 btAxisA = Vector3.UnitY; // pointing upwards, aka Y-axis

            spDoorHinge = new HingeConstraint(pDoorBody, btPivotA, btAxisA);

            //spDoorHinge.SetLimit(0.0f, (float)Math.PI / 2);
            // test problem values
            //spDoorHinge.SetLimit(-(float)Math.PI, (float)Math.PI * 0.8f);

            //spDoorHinge.SetLimit(1, -1);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI, 0.9f, 0.3f, 0.0f);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI, 0.9f, 0.01f, 0.0f); // "sticky limits"
            spDoorHinge.SetLimit(-(float)Math.PI * 0.25f, (float)Math.PI * 0.25f);
            //spDoorHinge.SetLimit(0, 0);
            World.AddConstraint(spDoorHinge);
            spDoorHinge.DebugDrawSize = 5;

            RigidBody pDropBody = LocalCreateRigidBody(10.0f, Matrix.Translation(-5.0f, 2.0f, 0.0f), shape);

            // create a generic 6DOF constraint

            //RigidBody pBodyA = LocalCreateRigidBody(mass, Matrix.Translation(10.0f, 6.0f, 0), shape);
            RigidBody pBodyA = LocalCreateRigidBody(0, Matrix.Translation(10, 6, 0), shape);
            //RigidBody pBodyA = LocalCreateRigidBody(0, Matrix.Translation(10, 6, 0), null);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            RigidBody pBodyB = LocalCreateRigidBody(mass, Matrix.Translation(0, 6, 0), shape);
            //RigidBody pBodyB = LocalCreateRigidBody(0, Matrix.Translation(0, 6, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;

            frameInA = Matrix.Translation(-5, 0, 0);
            frameInB = Matrix.Translation(5, 0, 0);

            Generic6DofConstraint pGen6DOF = new Generic6DofConstraint(pBodyA, pBodyB, frameInA, frameInB, true);
            //Generic6DofConstraint pGen6DOF = new Generic6DofConstraint(pBodyA, pBodyB, frameInA, frameInB, false);
            pGen6DOF.LinearLowerLimit = new Vector3(-10, -2, -1);
            pGen6DOF.LinearUpperLimit = new Vector3(10, 2, 1);
            //pGen6DOF.LinearLowerLimit = new Vector3(-10, 0, 0);
            //pGen6DOF.LinearUpperLimit = new Vector3(10, 0, 0);
            //pGen6DOF.LinearLowerLimit = new Vector3(0, 0, 0);
            //pGen6DOF.LinearUpperLimit = new Vector3(0, 0, 0);

            //pGen6DOF.TranslationalLimitMotor.EnableMotor[0] = true;
            //pGen6DOF.TranslationalLimitMotor.TargetVelocity = new Vector3(5, 0, 0);
            //pGen6DOF.TranslationalLimitMotor.MaxMotorForce = new Vector3(0.1f, 0, 0);

            //pGen6DOF.AngularLowerLimit = new Vector3(0, (float)Math.PI * 0.9f, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, -(float)Math.PI * 0.9f, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, 0, -(float)Math.PI);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0, (float)Math.PI);

            pGen6DOF.AngularLowerLimit = new Vector3(-(float)Math.PI / 4, -0.75f, -(float)Math.PI * 0.4f);
            pGen6DOF.AngularUpperLimit = new Vector3((float)Math.PI / 4, 0.75f, (float)Math.PI * 0.4f);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -0.75f, (float)Math.PI * 0.8f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0.75f, -(float)Math.PI * 0.8f);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -(float)Math.PI * 0.8f, (float)Math.PI * 1.98f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, (float)Math.PI * 0.8f, -(float)Math.PI * 1.98f);

            //pGen6DOF.AngularLowerLimit = new Vector3(-0.75f, -0.5f, -0.5f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0.75f, 0.5f, 0.5f);
            //pGen6DOF.AngularLowerLimit = new Vector3(-0.75f, 0, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0.75f, 0, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -0.7f, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0.7f, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(-1, 0, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(1, 0, 0);

            // create a ConeTwist constraint

            pBodyA = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, 5, 0), shape);
            //pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-10, 5, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            pBodyB = LocalCreateRigidBody(0, Matrix.Translation(-10, -5, 0), shape);
            //pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, -5, 0), shape);

            frameInA = Matrix.RotationYawPitchRoll(0, 0, (float)Math.PI / 2);
            frameInA *= Matrix.Translation(0, -5, 0);
            frameInB = Matrix.RotationYawPitchRoll(0, 0, (float)Math.PI / 2);
            frameInB *= Matrix.Translation(0, 5, 0);

            coneTwist = new ConeTwistConstraint(pBodyA, pBodyB, frameInA, frameInB);
            //coneTwist.SetLimit((float)Math.PI / 4, (float)Math.PI / 4, (float)Math.PI * 0.8f);
            //coneTwist.SetLimit((((float)Math.PI / 4) * 0.6f), (float)Math.PI / 4, (float)Math.PI * 0.8f, 1.0f); // soft limit == hard limit
            coneTwist.SetLimit((((float)Math.PI / 4) * 0.6f), (float)Math.PI / 4, (float)Math.PI * 0.8f, 0.5f);
            World.AddConstraint(coneTwist, true);
            coneTwist.DebugDrawSize = 5;

            // Hinge connected to the world, with motor (to hinge motor with new and old constraint solver)

            RigidBody pBody = LocalCreateRigidBody(1.0f, Matrix.Identity, shape);
            pBody.ActivationState = ActivationState.DisableDeactivation;
            Vector3 pivotA = new Vector3(10.0f, 0.0f, 0.0f);
            btAxisA = new Vector3(0.0f, 0.0f, 1.0f);

            HingeConstraint pHinge = new HingeConstraint(pBody, pivotA, btAxisA);
            //pHinge.EnableAngularMotor(true, -1.0f, 0.165f); // use for the old solver
            pHinge.EnableAngularMotor(true, -1.0f, 1.65f); // use for the new SIMD solver
            World.AddConstraint(pHinge);
            pHinge.DebugDrawSize = 5;

            // create a universal joint using generic 6DOF constraint
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(20, 4, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB (child) below it :
            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(20, 0, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some (arbitrary) data to build constraint frames
            Vector3 parentAxis = new Vector3(1, 0, 0);
            Vector3 childAxis = new Vector3(0, 0, 1);
            Vector3 anchor = new Vector3(20, 2, 0);

            UniversalConstraint pUniv = new UniversalConstraint(pBodyA, pBodyB, anchor, parentAxis, childAxis);
            pUniv.SetLowerLimit(-(float)Math.PI / 4, -(float)Math.PI / 4);
            pUniv.SetUpperLimit((float)Math.PI / 4, (float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(pUniv, true);
            // draw constraint frames and limits for debugging
            pUniv.DebugDrawSize = 5;

            World.AddConstraint(pGen6DOF, true);
            pGen6DOF.DebugDrawSize = 5;

            // create a generic 6DOF constraint with springs

            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-20, 16, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, 16, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;

            frameInA = Matrix.Translation(10, 0, 0);
            frameInB = Matrix.Identity;

            Generic6DofSpringConstraint pGen6DOFSpring = new Generic6DofSpringConstraint(pBodyA, pBodyB, frameInA, frameInB, true)
            {
                LinearUpperLimit = new Vector3(5, 0, 0),
                LinearLowerLimit = new Vector3(-5, 0, 0),
                AngularLowerLimit = new Vector3(0, 0, -1.5f),
                AngularUpperLimit = new Vector3(0, 0, 1.5f),
                DebugDrawSize = 5
            };
            World.AddConstraint(pGen6DOFSpring, true);

            pGen6DOFSpring.EnableSpring(0, true);
            pGen6DOFSpring.SetStiffness(0, 39.478f);
            pGen6DOFSpring.SetDamping(0, 0.5f);
            pGen6DOFSpring.EnableSpring(5, true);
            pGen6DOFSpring.SetStiffness(5, 39.478f);
            pGen6DOFSpring.SetDamping(0, 0.3f);
            pGen6DOFSpring.SetEquilibriumPoint();

            // create a Hinge2 joint
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-20, 4, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB (child) below it :
            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-20, 0, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some data to build constraint frames
            parentAxis = new Vector3(0, 1, 0);
            childAxis = new Vector3(1, 0, 0);
            anchor = new Vector3(-20, 0, 0);
            Hinge2Constraint pHinge2 = new Hinge2Constraint(pBodyA, pBodyB, anchor, parentAxis, childAxis);
            pHinge2.SetLowerLimit(-(float)Math.PI / 4);
            pHinge2.SetUpperLimit((float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(pHinge2, true);
            // draw constraint frames and limits for debugging
            pHinge2.DebugDrawSize = 5;

            // create a Hinge joint between two dynamic bodies
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(1.0f, Matrix.Translation(-20, -2, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB:
            pBodyB = LocalCreateRigidBody(10.0f, Matrix.Translation(-30, -2, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some data to build constraint frames
            axisA = new Vector3(0, 1, 0);
            axisB = new Vector3(0, 1, 0);
            Vector3 pivotA2 = new Vector3(-5, 0, 0);
            Vector3 pivotB = new Vector3(5, 0, 0);
            spHingeDynAB = new HingeConstraint(pBodyA, pBodyB, pivotA2, pivotB, axisA, axisB);
            spHingeDynAB.SetLimit(-(float)Math.PI / 4, (float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(spHingeDynAB, true);
            // draw constraint frames and limits for debugging
            spHingeDynAB.DebugDrawSize = 5;
        }
示例#2
0
        private void AddVertexGraph(VertexGraph graph)
        {
            Individual = graph.Vertices.Select(vertex =>
            {
                var mass = 10000;
                var motionState = new DefaultMotionState();
                var collisionShape = new BoxShape(1);

                var info = new RigidBodyConstructionInfo(mass, motionState, collisionShape);
                var rigidBody = new VertexBoundRigidBody(vertex, info);

                return rigidBody;
            }).ToList();

            foreach (var body in Individual)
            {
                // Select the 3 nearest vertices, excluding this one
                var nearest = Individual.OrderBy(a => a.Binding.DistanceTo(body.Binding))
                                         .Where(a => a != body)
                                         .Take(3);
                foreach (var other in nearest)
                {
                    // TODO: What are these matrices supposed to be?
                    var frameInA = body.MotionState.WorldTransform;
                    var frameInB = other.MotionState.WorldTransform;

                    // TODO: How do you specify the spring's springiness?
                    var constraint = new Generic6DofSpringConstraint(body, other, frameInA, frameInB, true);

                    // TODO: Now how do I apply this to the bodies?
                    body.AddConstraintRef(constraint);
                    other.AddConstraintRef(constraint);
                }
            }
        }
 public Generic6DofSpringConstraint CreateGeneric6DofSpringConstraint(RigidBody rbA, RigidBody rbB, ref Matrix frameInA, ref Matrix frameInB, bool useLinearReferenceFrameA)
 {
     Generic6DofSpringConstraint constraint = new Generic6DofSpringConstraint(rbA, rbB, frameInA, frameInB, useLinearReferenceFrameA);
     _allocatedConstraints.Add(constraint);
     return constraint;
 }
示例#4
0
        public Physics()
        {
            SetupEmptyDynamicsWorld();

            CollisionShape groundShape = new BoxShape(50, 1, 50);
            //CollisionShape groundShape = new StaticPlaneShape(Vector3.UnitY, 40);
            CollisionShapes.Add(groundShape);
            RigidBody body = LocalCreateRigidBody(0, Matrix.Translation(0, -16, 0), groundShape);
            body.UserObject = "Ground";

            CollisionShape shape = new BoxShape(new Vector3(CubeHalfExtents));
            CollisionShapes.Add(shape);


            float mass = 1.0f;

            RigidBody body0 = LocalCreateRigidBody(mass, Matrix.Translation(0, 20, 0), shape);

            RigidBody body1 = null;//LocalCreateRigidBody(mass, Matrix.Translation(2*CUBE_HALF_EXTENTS,20,0), shape);
            //RigidBody body1 = LocalCreateRigidBody(0, Matrix.Translation(2*CUBE_HALF_EXTENTS,20,0), null);
            //body1.ActivationState = ActivationState.DisableDeactivation;
            //body1.SetDamping(0.3f, 0.3f);

            Vector3 pivotInA = new Vector3(CubeHalfExtents, -CubeHalfExtents, -CubeHalfExtents);
            Vector3 axisInA = new Vector3(0, 0, 1);

            Vector3 pivotInB;
            if (body1 != null)
            {
                Matrix transform = Matrix.Invert(body1.CenterOfMassTransform) * body0.CenterOfMassTransform;
                pivotInB = Vector3.TransformCoordinate(pivotInA, transform);
            }
            else
            {
                pivotInB = pivotInA;
            }

            Vector3 axisInB;
            if (body1 != null)
            {
                Matrix transform = Matrix.Invert(body1.CenterOfMassTransform) * body1.CenterOfMassTransform;
                axisInB = Vector3.TransformCoordinate(axisInA, transform);
            }
            else
            {
                axisInB = Vector3.TransformCoordinate(axisInA, body0.CenterOfMassTransform);
            }

            if (P2P)
            {
                TypedConstraint p2p = new Point2PointConstraint(body0, pivotInA);
                //TypedConstraint p2p = new Point2PointConstraint(body0,body1,pivotInA,pivotInB);
                //TypedConstraint hinge = new HingeConstraint(body0,body1,pivotInA,pivotInB,axisInA,axisInB);
                World.AddConstraint(p2p);
                p2p.DebugDrawSize = 5;
            }
            else
            {
                HingeConstraint hinge = new HingeConstraint(body0, pivotInA, axisInA);

                //use zero targetVelocity and a small maxMotorImpulse to simulate joint friction
                //float	targetVelocity = 0.f;
                //float	maxMotorImpulse = 0.01;
                float targetVelocity = 1.0f;
                float maxMotorImpulse = 1.0f;
                hinge.EnableAngularMotor(true, targetVelocity, maxMotorImpulse);
                World.AddConstraint(hinge);
                hinge.DebugDrawSize = 5;
            }



            //create a slider, using the generic D6 constraint
            Vector3 sliderWorldPos = new Vector3(0, 10, 0);
            Vector3 sliderAxis = Vector3.UnitX;
            float angle = 0;//SIMD_RADS_PER_DEG * 10.f;
            Matrix trans = Matrix.RotationAxis(sliderAxis, angle) * Matrix.Translation(sliderWorldPos);
            d6body0 = LocalCreateRigidBody(mass, trans, shape);
            d6body0.ActivationState = ActivationState.DisableDeactivation;

            RigidBody fixedBody1 = LocalCreateRigidBody(0, trans, null);
            World.AddRigidBody(fixedBody1);

            Matrix frameInA = Matrix.Translation(0, 5, 0);
            Matrix frameInB = Matrix.Translation(0, 5, 0);

            //bool useLinearReferenceFrameA = false;//use fixed frame B for linear llimits
            bool useLinearReferenceFrameA = true;//use fixed frame A for linear llimits
            spSlider6Dof = new Generic6DofConstraint(fixedBody1, d6body0, frameInA, frameInB, useLinearReferenceFrameA);
            spSlider6Dof.LinearLowerLimit = lowerSliderLimit;
            spSlider6Dof.LinearUpperLimit = hiSliderLimit;

            //range should be small, otherwise singularities will 'explode' the constraint
            //spSlider6Dof.AngularLowerLimit = new Vector3(-1.5f,0,0);
            //spSlider6Dof.AngularUpperLimit = new Vector3(1.5f,0,0);
            //spSlider6Dof.AngularLowerLimit = new Vector3(0,0,0);
            //spSlider6Dof.AngularUpperLimit = new Vector3(0,0,0);
            spSlider6Dof.AngularLowerLimit = new Vector3((float)-Math.PI, 0, 0);
            spSlider6Dof.AngularUpperLimit = new Vector3(1.5f, 0, 0);

            spSlider6Dof.TranslationalLimitMotor.EnableMotor[0] = true;
            spSlider6Dof.TranslationalLimitMotor.TargetVelocity = new Vector3(-5.0f, 0, 0);
            spSlider6Dof.TranslationalLimitMotor.MaxMotorForce = new Vector3(0.1f, 0, 0);

            World.AddConstraint(spSlider6Dof);
            spSlider6Dof.DebugDrawSize = 5;



            // create a door using hinge constraint attached to the world

            CollisionShape pDoorShape = new BoxShape(2.0f, 5.0f, 0.2f);
            CollisionShapes.Add(pDoorShape);
            RigidBody pDoorBody = LocalCreateRigidBody(1.0f, Matrix.Translation(-5.0f, -2.0f, 0.0f), pDoorShape);
            pDoorBody.ActivationState = ActivationState.DisableDeactivation;
            Vector3 btPivotA = new Vector3(10.0f + 2.1f, -2.0f, 0.0f); // right next to the door slightly outside
            Vector3 btAxisA = Vector3.UnitY; // pointing upwards, aka Y-axis

            spDoorHinge = new HingeConstraint(pDoorBody, btPivotA, btAxisA);

            //spDoorHinge.SetLimit(0.0f, (float)Math.PI / 2);
            // test problem values
            //spDoorHinge.SetLimit(-(float)Math.PI, (float)Math.PI * 0.8f);

            //spDoorHinge.SetLimit(1, -1);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI, 0.9f, 0.3f, 0.0f);
            //spDoorHinge.SetLimit(-(float)Math.PI * 0.8f, (float)Math.PI, 0.9f, 0.01f, 0.0f); // "sticky limits"
            spDoorHinge.SetLimit(-(float)Math.PI * 0.25f, (float)Math.PI * 0.25f);
            //spDoorHinge.SetLimit(0, 0);
            World.AddConstraint(spDoorHinge);
            spDoorHinge.DebugDrawSize = 5;

            RigidBody pDropBody = LocalCreateRigidBody(10.0f, Matrix.Translation(-5.0f, 2.0f, 0.0f), shape);



            // create a generic 6DOF constraint

            //RigidBody pBodyA = LocalCreateRigidBody(mass, Matrix.Translation(10.0f, 6.0f, 0), shape);
            RigidBody pBodyA = LocalCreateRigidBody(0, Matrix.Translation(10, 6, 0), shape);
            //RigidBody pBodyA = LocalCreateRigidBody(0, Matrix.Translation(10, 6, 0), null);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            RigidBody pBodyB = LocalCreateRigidBody(mass, Matrix.Translation(0, 6, 0), shape);
            //RigidBody pBodyB = LocalCreateRigidBody(0, Matrix.Translation(0, 6, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;

            frameInA = Matrix.Translation(-5, 0, 0);
            frameInB = Matrix.Translation(5, 0, 0);

            Generic6DofConstraint pGen6DOF = new Generic6DofConstraint(pBodyA, pBodyB, frameInA, frameInB, true);
            //Generic6DofConstraint pGen6DOF = new Generic6DofConstraint(pBodyA, pBodyB, frameInA, frameInB, false);
            pGen6DOF.LinearLowerLimit = new Vector3(-10, -2, -1);
            pGen6DOF.LinearUpperLimit = new Vector3(10, 2, 1);
            //pGen6DOF.LinearLowerLimit = new Vector3(-10, 0, 0);
            //pGen6DOF.LinearUpperLimit = new Vector3(10, 0, 0);
            //pGen6DOF.LinearLowerLimit = new Vector3(0, 0, 0);
            //pGen6DOF.LinearUpperLimit = new Vector3(0, 0, 0);

            //pGen6DOF.TranslationalLimitMotor.EnableMotor[0] = true;
            //pGen6DOF.TranslationalLimitMotor.TargetVelocity = new Vector3(5, 0, 0);
            //pGen6DOF.TranslationalLimitMotor.MaxMotorForce = new Vector3(0.1f, 0, 0);

            //pGen6DOF.AngularLowerLimit = new Vector3(0, (float)Math.PI * 0.9f, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, -(float)Math.PI * 0.9f, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, 0, -(float)Math.PI);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0, (float)Math.PI);

            pGen6DOF.AngularLowerLimit = new Vector3(-(float)Math.PI / 4, -0.75f, -(float)Math.PI * 0.4f);
            pGen6DOF.AngularUpperLimit = new Vector3((float)Math.PI / 4, 0.75f, (float)Math.PI * 0.4f);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -0.75f, (float)Math.PI * 0.8f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0.75f, -(float)Math.PI * 0.8f);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -(float)Math.PI * 0.8f, (float)Math.PI * 1.98f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, (float)Math.PI * 0.8f, -(float)Math.PI * 1.98f);

            //pGen6DOF.AngularLowerLimit = new Vector3(-0.75f, -0.5f, -0.5f);
            //pGen6DOF.AngularUpperLimit = new Vector3(0.75f, 0.5f, 0.5f);
            //pGen6DOF.AngularLowerLimit = new Vector3(-0.75f, 0, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0.75f, 0, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(0, -0.7f, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(0, 0.7f, 0);
            //pGen6DOF.AngularLowerLimit = new Vector3(-1, 0, 0);
            //pGen6DOF.AngularUpperLimit = new Vector3(1, 0, 0);



            // create a ConeTwist constraint

            pBodyA = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, 5, 0), shape);
            //pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-10, 5, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            pBodyB = LocalCreateRigidBody(0, Matrix.Translation(-10, -5, 0), shape);
            //pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, -5, 0), shape);

            frameInA = Matrix.RotationYawPitchRoll(0, 0, (float)Math.PI / 2);
            frameInA *= Matrix.Translation(0, -5, 0);
            frameInB = Matrix.RotationYawPitchRoll(0, 0, (float)Math.PI / 2);
            frameInB *= Matrix.Translation(0, 5, 0);

            coneTwist = new ConeTwistConstraint(pBodyA, pBodyB, frameInA, frameInB);
            //coneTwist.SetLimit((float)Math.PI / 4, (float)Math.PI / 4, (float)Math.PI * 0.8f);
            //coneTwist.SetLimit((((float)Math.PI / 4) * 0.6f), (float)Math.PI / 4, (float)Math.PI * 0.8f, 1.0f); // soft limit == hard limit
            coneTwist.SetLimit((((float)Math.PI / 4) * 0.6f), (float)Math.PI / 4, (float)Math.PI * 0.8f, 0.5f);
            World.AddConstraint(coneTwist, true);
            coneTwist.DebugDrawSize = 5;



            // Hinge connected to the world, with motor (to hinge motor with new and old constraint solver)

            RigidBody pBody = LocalCreateRigidBody(1.0f, Matrix.Identity, shape);
            pBody.ActivationState = ActivationState.DisableDeactivation;
            Vector3 PivotA = new Vector3(10.0f, 0.0f, 0.0f);
            btAxisA = new Vector3(0.0f, 0.0f, 1.0f);

            HingeConstraint pHinge = new HingeConstraint(pBody, btPivotA, btAxisA);
            //pHinge.EnableAngularMotor(true, -1.0f, 0.165f); // use for the old solver
            pHinge.EnableAngularMotor(true, -1.0f, 1.65f); // use for the new SIMD solver
            World.AddConstraint(pHinge);
            pHinge.DebugDrawSize = 5;



            // create a universal joint using generic 6DOF constraint
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(20, 4, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB (child) below it :
            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(20, 0, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some (arbitrary) data to build constraint frames
            Vector3 parentAxis = new Vector3(1, 0, 0);
            Vector3 childAxis = new Vector3(0, 0, 1);
            Vector3 anchor = new Vector3(20, 2, 0);

            UniversalConstraint pUniv = new UniversalConstraint(pBodyA, pBodyB, anchor, parentAxis, childAxis);
            pUniv.SetLowerLimit(-(float)Math.PI / 4, -(float)Math.PI / 4);
            pUniv.SetUpperLimit((float)Math.PI / 4, (float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(pUniv, true);
            // draw constraint frames and limits for debugging
            pUniv.DebugDrawSize = 5;

            World.AddConstraint(pGen6DOF, true);
            pGen6DOF.DebugDrawSize = 5;



            // create a generic 6DOF constraint with springs 

            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-20, 16, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;

            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-10, 16, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;

            frameInA = Matrix.Translation(10, 0, 0);
            frameInB = Matrix.Identity;

            Generic6DofSpringConstraint pGen6DOFSpring = new Generic6DofSpringConstraint(pBodyA, pBodyB, frameInA, frameInB, true);
            pGen6DOFSpring.LinearUpperLimit = new Vector3(5, 0, 0);
            pGen6DOFSpring.LinearLowerLimit = new Vector3(-5, 0, 0);

            pGen6DOFSpring.AngularLowerLimit = new Vector3(0, 0, -1.5f);
            pGen6DOFSpring.AngularUpperLimit = new Vector3(0, 0, 1.5f);

            World.AddConstraint(pGen6DOFSpring, true);
            pGen6DOFSpring.DebugDrawSize = 5;

            pGen6DOFSpring.EnableSpring(0, true);
            pGen6DOFSpring.SetStiffness(0, 39.478f);
            pGen6DOFSpring.SetDamping(0, 0.5f);
            pGen6DOFSpring.EnableSpring(5, true);
            pGen6DOFSpring.SetStiffness(5, 39.478f);
            pGen6DOFSpring.SetDamping(0, 0.3f);
            pGen6DOFSpring.SetEquilibriumPoint();



            // create a Hinge2 joint
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(0, Matrix.Translation(-20, 4, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB (child) below it :
            pBodyB = LocalCreateRigidBody(1.0f, Matrix.Translation(-20, 0, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some data to build constraint frames
            parentAxis = new Vector3(0, 1, 0);
            childAxis = new Vector3(1, 0, 0);
            anchor = new Vector3(-20, 0, 0);
            Hinge2Constraint pHinge2 = new Hinge2Constraint(pBodyA, pBodyB, anchor, parentAxis, childAxis);
            pHinge2.SetLowerLimit(-(float)Math.PI / 4);
            pHinge2.SetUpperLimit((float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(pHinge2, true);
            // draw constraint frames and limits for debugging
            pHinge2.DebugDrawSize = 5;



            // create a Hinge joint between two dynamic bodies
            // create two rigid bodies
            // static bodyA (parent) on top:
            pBodyA = LocalCreateRigidBody(1.0f, Matrix.Translation(-20, -2, 0), shape);
            pBodyA.ActivationState = ActivationState.DisableDeactivation;
            // dynamic bodyB:
            pBodyB = LocalCreateRigidBody(10.0f, Matrix.Translation(-30, -2, 0), shape);
            pBodyB.ActivationState = ActivationState.DisableDeactivation;
            // add some data to build constraint frames
            Vector3 axisA = new Vector3(0, 1, 0);
            Vector3 axisB = new Vector3(0, 1, 0);
            Vector3 pivotA = new Vector3(-5, 0, 0);
            Vector3 pivotB = new Vector3(5, 0, 0);
            spHingeDynAB = new HingeConstraint(pBodyA, pBodyB, pivotA, pivotB, axisA, axisB);
            spHingeDynAB.SetLimit(-(float)Math.PI / 4, (float)Math.PI / 4);
            // add constraint to world
            World.AddConstraint(spHingeDynAB, true);
            // draw constraint frames and limits for debugging
            spHingeDynAB.DebugDrawSize = 5;
        }