Trying to bounce a box with a plane using DirectX 11.1

[andreahmed]

I'm trying to simulate a box that bounces with a plane and I'm beginner with bullet physics. I created a plane (box) and and a box that is falling. The problem is the ball is stalled while colliding with the plane and doesn't rotate (no bouncing effect), even if the box is rotated so that it can sharply bounce with the plane. Here is my configuration.

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if (m_pBoxMotionState) 
    {
        btTransform transform;
        // get the world transform from our motion state
        m_pBoxMotionState->getWorldTransform(transform);

        btQuaternion quat;
        quat.setEuler(0, 290, 0); //or quat.setEulerZYX depending on the ordering you want
        transform.setRotation(quat);

        XMMATRIX world = btTransform_to_XMMATRIX(transform);
        m_Cube->Draw(world, m_Graphics.getViewMatrix(), m_Graphics.getProjectionMatrix());
    }


m_Grid.CreateGrid(360.0f, 360.0f, 50, 50);
    m_Grid.SetPosition(1, -90, 1);
    m_Cube = GeometricPrimitive::CreateCube(m_Graphics.getContext(), 5.0f, false);

      m_pCollisionConfiguration = new btDefaultCollisionConfiguration();
            // create the dispatcher
            m_pDispatcher = new btCollisionDispatcher(m_pCollisionConfiguration);
            // create the broadphase
            m_pBroadphase = new btDbvtBroadphase();
            // create the constraint solver
            m_pSolver = new btSequentialImpulseConstraintSolver();
            // create the world
            m_pWorld = new btDiscreteDynamicsWorld(m_pDispatcher, m_pBroadphase, m_pSolver, m_pCollisionConfiguration);
            m_pWorld->setGravity(btVector3(0, -10, 0));

            btBoxShape* pBoxShape = new btBoxShape(btVector3(1.0f, 1.0f, 1.0f));
            // give our box an initial position of (0,0,0)
            btTransform transform;
            transform.setIdentity();
            transform.setOrigin(btVector3(0.0f, 50, 0.0f));
            pBoxShape->calculateLocalInertia(4, btVector3(0, 0, 0));
            // create a motion state
            m_pBoxMotionState = new btDefaultMotionState(transform);
            // create the rigid body construction info object, giving it a 
            // mass of 1, the motion state, and the shape
            btRigidBody::btRigidBodyConstructionInfo rbInfo(4.0f, m_pBoxMotionState, pBoxShape);
            btRigidBody* pRigidBody = new btRigidBody(rbInfo);
            pGroundShape->calculateLocalInertia(0, btVector3(0, 0, 0));
            btBoxShape* pGroundShape = new btBoxShape(btVector3(360, 1,360));
            btTransform groundShapeTransform;
            groundShapeTransform.setIdentity();
            groundShapeTransform.setOrigin(btVector3(1.0f, -90.0f, 1.0f));

            // create a motion state
            m_pGroundMotionState = new btDefaultMotionState(groundShapeTransform);
            btRigidBody::btRigidBodyConstructionInfo rbGroundInfo(0, m_pGroundMotionState, pGroundShape);
            rbGroundInfo.m_friction = 1.0f;
            rbGroundInfo.m_restitution = 1.0f;
            btRigidBody* pRigidBodyGround = new btRigidBody(rbGroundInfo);

            // inform our world that we just created a new rigid body for 
            // it to manage
            m_pWorld->addRigidBody(pRigidBodyGround);
            m_pWorld->addRigidBody(pRigidBody);

[Flix]

I'm trying to simulate a box that bounces with a plane and I'm beginner with bullet physics. I created a plane (box) and and a box that is falling

Ok, you got a box and a plane.

The problem is the ball is stalled while colliding with the plane

I suppose you mean, the box is stalled...

Here is my configuration.[...]

pBoxShape->calculateLocalInertia(4, btVector3(0, 0, 0));
[...]
pGroundShape->calculateLocalInertia(0, btVector3(0, 0, 0));

This is wrong!

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virtual void btCollisionShape::calculateLocalInertia 	( 	btScalar  	mass,
		btVector3 &  	inertia	 
	) 			const

Here the inertia is just calculated and returned by reference without modifying the collision shape (it's a const method!).Try something like:

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btVector3 localInertia;
pBoxShape->calculateLocalInertia(4, localInertia);
btRigidBody::btRigidBodyConstructionInfo rbInfo(4,pBoxMotionState,pBoxShape,localInertia);

[Also note that inertia should be strictly necessary only for moving bodies].

[andreahmed]

Thanks, but that actually didn't solve the problem. Still the box sinks into the ground and never get bounced