/*
 * ODE::ContactJoint::initialize( contact, world, jointGroup )
 * --
 * Create and return a new contact joint for the given contact.
 */
static VALUE
ode_contactJoint_init( argc, argv, self )
	 int		argc;
	 VALUE		*argv, self;
{
	debugMsg(( "ODE::Joint init." ));

	if ( !check_joint(self) ) {
		ode_JOINT		*ptr;
		VALUE			world, contact, jointGroup = Qnil;
		dWorldID		worldId;
		ode_CONTACT		*contactPtr;
		dJointGroupID	jointGroupId = 0;

		/* Scan arguments */
		debugMsg(( "Creating a new Joint: checking args." ));
		rb_scan_args( argc, argv, "21", &world, &contact, &jointGroup );

		/* Unwrap the underlying values of the world, the contact object, and
		   the joint group if it was specified. */
		worldId = ode_get_world( world );
		contactPtr = ode_get_contact( contact );
		if ( jointGroup ) {
			ode_JOINTGROUP	*jointGroupPtr = ode_get_jointGroup( jointGroup );
			jointGroupId = jointGroupPtr->id;
			debugMsg(( "Got a JointGroup for new Joint: <%p>", jointGroupId ));
		}

		else {
			debugMsg(( "No JointGroup for new Joint" ));
		}

		/* Allocate a joint struct and set its members */
		debugMsg(( "Creating a new Joint: ALLOCing and setting struct members." ));
		DATA_PTR( self )	= ptr = ode_joint_alloc();

		ptr->object			= self;
		ptr->world			= world;
		ptr->contact		= contact;
		ptr->jointGroup		= jointGroup;
		ptr->obsolete		= Qfalse;

		ptr->id = dJointCreateContact( worldId, jointGroupId, contactPtr->contact );

		/* Set the Ruby struct as the data pointer of the ODE object */
		dJointSetData( ptr->id, ptr );

		/* Register the new joint with the joint group specified, if there was
		   one. */
		if ( jointGroup )
			ode_jointGroup_register_joint( jointGroup, self );
	}

	return self;
}

/*
 * ODE::ContactJoint#contact
 * --
 * Returns the ODE::Contact object associated with the joint.
 */
static VALUE
ode_contactJoint_contact( self )
	 VALUE self;
{
	ode_JOINT	*ptr = get_joint( self );
	return ptr->contact;
}