BtBody Class Reference

Wrapper class for a bullet btRigidBody, that bridges between RobWork and Bullet. More...

#include <BtBody.hpp>

Classes
struct	BodyMetaData
	Data structure to attach to bullet bodies, allowing friction and restitution to be specified separately for each pair of bodies. More...
struct	GeometryMetaData
	Data structure to attch to bullet collision shapes. More...

Public Member Functions
	BtBody (rw::core::Ptr< rwsim::dynamics::Body > body, const rwsim::dynamics::MaterialDataMap *frictionMap, const rwsim::dynamics::ContactDataMap *collisionMap, btDynamicsWorld *btWorld, const rw::kinematics::State &state)
	Construct new bullet body for the given world. More...
virtual	~BtBody ()
	Destructor.
rw::core::Ptr< rwsim::dynamics::Body >	getRwBody () const
	Get the RobWork body. More...
btRigidBody *	getBulletBody () const
	Get the underlying btRigidBody from Bullet. More...
void	update (double dt, rw::kinematics::State &state) const
	Update the position of all kinematic bodies. More...
void	postupdate (rw::kinematics::State &state) const
	This method updates the state with state info of the Bullet object. Which means that Bullet states are converted to rw states. More...
bool	isDynamic () const
	Test whether the object is dynamic (equivalent to the RigidBody type in RobWork). More...
const rw::math::Transform3D &	getBodyTcom () const
	Get the transform from the body frame to the center of mass frame. More...
rw::math::Transform3D	getWorldTcom () const
	Get the current transform of the Bullet body. More...

Detailed Description

Wrapper class for a bullet btRigidBody, that bridges between RobWork and Bullet.

Constructor & Destructor Documentation

BtBody()

BtBody	(	rw::core::Ptr< rwsim::dynamics::Body >	body,
		const rwsim::dynamics::MaterialDataMap *	frictionMap,
		const rwsim::dynamics::ContactDataMap *	collisionMap,
		btDynamicsWorld *	btWorld,
		const rw::kinematics::State &	state
	)

Construct new bullet body for the given world.

Parameters

body	[in] the RobWork body to create bullet body for.
frictionMap	[in] the friction map to look up in (must point to the same map for two objects in contact).
collisionMap	[in] the collision map to look up in (must point to the same map for two objects in contact).
btWorld	[in] the Bullet world to add the body to.
state	[in] the initial state with the initial position and velocity for the body.

Note

The initial body state is set when the body is constructed. It is not possible to reset the body position and velocity after creation. Instead the body must be deleted and created again.

Member Function Documentation

getBodyTcom()

const rw::math::Transform3D& getBodyTcom

(

)

const

Get the transform from the body frame to the center of mass frame.

Note

In Bullet the body frame must lie in the center of gravity, and the axes must coincide with the principal axes of inertia. This transform gives the relation between the body frame used in RobWork and the body frame used internally in Bullet.

Returns

a reference to the transform.

getBulletBody()

btRigidBody* getBulletBody

(

)

const

Get the underlying btRigidBody from Bullet.

Note

A btRigidBody can both be static, kinematic or dynamic. This is different than the RobWork RigidBody type, as the RigidBody type in RobWork is equivalent to a dynamic btRigidBody only.

Returns

a pointer to a btRigidBody.

getRwBody()

rw::core::Ptr<rwsim::dynamics::Body> getRwBody

(

)

const

Get the RobWork body.

Returns

a smart pointer to a RobWork Body.

getWorldTcom()

rw::math::Transform3D getWorldTcom

(

)

const

Get the current transform of the Bullet body.

Note

This transform is to the Bullet body frame which is different than the RobWork body frame - see getBodyTcom .

Returns

the current transform.

isDynamic()

bool isDynamic

(

)

const

Test whether the object is dynamic (equivalent to the RigidBody type in RobWork).

Returns

true if object is dynamic, false if object is kinematic or static.

postupdate()

void postupdate

(

rw::kinematics::State &

state

)

const

This method updates the state with state info of the Bullet object. Which means that Bullet states are converted to rw states.

Parameters

state

[in/out] the state is updated with new positions and velocities.

update()

void update	(	double	dt,
		rw::kinematics::State &	state
	)		const

Update the position of all kinematic bodies.

Parameters

dt	[in] the size of the timestep.
state	[in/out] the state with updated position for kinematic bodies.

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The documentation for this class was generated from the following file:

• BtBody.hpp