btBoxShape spinning out of control

[ofcbobrovsky]

I'm creating rigid bodies using btBoxShape, but the boxes are spinning wildly, and only stop if I apply a ridiculous amount of friction to them. They started out spinning, and they appear to only be spinning wildly on the Y axis.

Here is what is happening

Here are the relevant parts of my code:

Creating the world:

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	m_pBroadphase = new btDbvtBroadphase();

	m_pCollisionConfig = new btDefaultCollisionConfiguration();
	m_pCollisionDispatcher = new btCollisionDispatcher( m_pCollisionConfig );

	m_pPhysicsSolver = new btSequentialImpulseConstraintSolver();

	// Create the world
	m_pPhysWorld = new btDiscreteDynamicsWorld( m_pCollisionDispatcher, m_pBroadphase, m_pPhysicsSolver, m_pCollisionConfig );
	m_pPhysWorld->setGravity( btVector3( 0, -9.8f, 0 ) );

Creating the rigid body:

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	// Create the collision shape
	m_pBoxCollision = new btBoxShape( btVector3( 0.5f, 0.5f, 0.5f ) );
	boxMass = 1.0f;
	boxInertia = btVector3( 0.0f, 0.0f, 0.0f );
	m_pBoxCollision->calculateLocalInertia( boxMass, boxInertia );
	// Create the motion state
	boxTrans.setIdentity();
	boxTrans.setOrigin( ConversionUtil::vec3_to_btVector3( this->getPosition() ) );
	m_pBoxMotion = new btDefaultMotionState( boxTrans );
	// Create rigid body
	btRigidBody::btRigidBodyConstructionInfo boxRigidBodyInfo( boxMass, m_pBoxMotion, m_pBoxCollision, boxInertia );
	//boxRigidBodyInfo.m_friction = 25.0f;
	m_pBoxBody = new btRigidBody( boxRigidBodyInfo );
	// Add box physics to world
	GetGame()->getRenderer()->getWorld()->addRigidBody( m_pBoxBody );

Stepping the world:

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	m_pPhysWorld->stepSimulation( (btScalar)GetGame()->getFrameTimeS(), 10 );

Also, converting the transform to glm for OpenGL:

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	btTransform trans;
	btScalar matrixRaw[16];
	glm::mat4 matrix;
	m_pBoxBody->getMotionState( )->getWorldTransform( trans );
	trans.getOpenGLMatrix( matrixRaw );
	matrix = ConversionUtil::btScalar_to_mat4( &matrixRaw[0] );

I've tried multiple methods for converting to a rotation matrix and all of them have the same result.

If I had to guess the problem would be in the stepping part, to be honest I'm still not too sure as to how that works. My game is running at about 1200 FPS currently, although when I locked it to around 60 FPS and adjusted the step function, the boxes behaved the same. Also most of this code is just copied from the tutorials, I've looked it over countless times to find differences but maybe someone else's eyes can find something I missed.

[ezraanderson]

~
I experiences this also in my current demo. It helps alittle by adding damping

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m_bodies[i]->setDamping(0.05, 0.85);
m_bodies[i]->setDeactivationTime(0.8);
m_bodies[i]->setSleepingThresholds(1.6, 2.5);

edit:

hey started out spinning

My issues is probably differnet.

edit:

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   boxTrans.setOrigin( ConversionUtil::vec3_to_btVector3( this->getPosition() ) );

Is the shape being attached to the center of the body ?