A rigid body. These are created via b2World::CreateBody. More...

#include <b2_body.h>

Public Member Functions
b2Fixture *	CreateFixture (const b2FixtureDef *def)

b2Fixture *	CreateFixture (const b2Shape *shape, float density)

void	DestroyFixture (b2Fixture *fixture)

void	SetTransform (const b2Vec2 &position, float angle)

const b2Transform &	GetTransform () const

const b2Vec2 &	GetPosition () const

float	GetAngle () const

const b2Vec2 &	GetWorldCenter () const
	Get the world position of the center of mass.

const b2Vec2 &	GetLocalCenter () const
	Get the local position of the center of mass.

void	SetLinearVelocity (const b2Vec2 &v)

const b2Vec2 &	GetLinearVelocity () const

void	SetAngularVelocity (float omega)

float	GetAngularVelocity () const

void	ApplyForce (const b2Vec2 &force, const b2Vec2 &point, bool wake)

void	ApplyForceToCenter (const b2Vec2 &force, bool wake)

void	ApplyTorque (float torque, bool wake)

void	ApplyLinearImpulse (const b2Vec2 &impulse, const b2Vec2 &point, bool wake)

void	ApplyLinearImpulseToCenter (const b2Vec2 &impulse, bool wake)

void	ApplyAngularImpulse (float impulse, bool wake)

float	GetMass () const

float	GetInertia () const

void	GetMassData (b2MassData *data) const

void	SetMassData (const b2MassData *data)

void	ResetMassData ()

b2Vec2	GetWorldPoint (const b2Vec2 &localPoint) const

b2Vec2	GetWorldVector (const b2Vec2 &localVector) const

b2Vec2	GetLocalPoint (const b2Vec2 &worldPoint) const

b2Vec2	GetLocalVector (const b2Vec2 &worldVector) const

b2Vec2	GetLinearVelocityFromWorldPoint (const b2Vec2 &worldPoint) const

b2Vec2	GetLinearVelocityFromLocalPoint (const b2Vec2 &localPoint) const

float	GetLinearDamping () const
	Get the linear damping of the body.

void	SetLinearDamping (float linearDamping)
	Set the linear damping of the body.

float	GetAngularDamping () const
	Get the angular damping of the body.

void	SetAngularDamping (float angularDamping)
	Set the angular damping of the body.

float	GetGravityScale () const
	Get the gravity scale of the body.

void	SetGravityScale (float scale)
	Set the gravity scale of the body.

void	SetType (b2BodyType type)
	Set the type of this body. This may alter the mass and velocity.

b2BodyType	GetType () const
	Get the type of this body.

void	SetBullet (bool flag)
	Should this body be treated like a bullet for continuous collision detection?

bool	IsBullet () const
	Is this body treated like a bullet for continuous collision detection?

void	SetSleepingAllowed (bool flag)

bool	IsSleepingAllowed () const
	Is this body allowed to sleep.

void	SetAwake (bool flag)

bool	IsAwake () const

void	SetEnabled (bool flag)

bool	IsEnabled () const
	Get the active state of the body.

void	SetFixedRotation (bool flag)

bool	IsFixedRotation () const
	Does this body have fixed rotation?

b2Fixture *	GetFixtureList ()
	Get the list of all fixtures attached to this body.

const b2Fixture *	GetFixtureList () const

b2JointEdge *	GetJointList ()
	Get the list of all joints attached to this body.

const b2JointEdge *	GetJointList () const

b2ContactEdge *	GetContactList ()

const b2ContactEdge *	GetContactList () const

b2Body *	GetNext ()
	Get the next body in the world's body list.

const b2Body *	GetNext () const

b2BodyUserData &	GetUserData ()
	Get the user data pointer that was provided in the body definition.

void	SetUserData (void *data)
	Set the user data. Use this to store your application specific data.

b2World *	GetWorld ()
	Get the parent world of this body.

const b2World *	GetWorld () const

void	Dump ()
	Dump this body to a file.

Friends
class	b2World

class	b2Island

class	b2ContactManager

class	b2ContactSolver

class	b2Contact

class	b2DistanceJoint

class	b2FrictionJoint

class	b2GearJoint

class	b2MotorJoint

class	b2MouseJoint

class	b2PrismaticJoint

class	b2PulleyJoint

class	b2RevoluteJoint

class	b2RopeJoint

class	b2WeldJoint

class	b2WheelJoint

Detailed Description

A rigid body. These are created via b2World::CreateBody.

Member Function Documentation

◆ ApplyAngularImpulse()

void b2Body::ApplyAngularImpulse	(	float	impulse,
		bool	wake
	)

inline

Apply an angular impulse.

Parameters

impulse	the angular impulse in units of kgmm/s
wake	also wake up the body

◆ ApplyForce()

void b2Body::ApplyForce	(	const b2Vec2 &	force,
		const b2Vec2 &	point,
		bool	wake
	)

inline

Apply a force at a world point. If the force is not applied at the center of mass, it will generate a torque and affect the angular velocity. This wakes up the body.

Parameters

force	the world force vector, usually in Newtons (N).
point	the world position of the point of application.
wake	also wake up the body

◆ ApplyForceToCenter()

void b2Body::ApplyForceToCenter	(	const b2Vec2 &	force,
		bool	wake
	)

inline

Apply a force to the center of mass. This wakes up the body.

Parameters

force	the world force vector, usually in Newtons (N).
wake	also wake up the body

◆ ApplyLinearImpulse()

void b2Body::ApplyLinearImpulse	(	const b2Vec2 &	impulse,
		const b2Vec2 &	point,
		bool	wake
	)

inline

Apply an impulse at a point. This immediately modifies the velocity. It also modifies the angular velocity if the point of application is not at the center of mass. This wakes up the body.

Parameters

impulse	the world impulse vector, usually in N-seconds or kg-m/s.
point	the world position of the point of application.
wake	also wake up the body

◆ ApplyLinearImpulseToCenter()

void b2Body::ApplyLinearImpulseToCenter	(	const b2Vec2 &	impulse,
		bool	wake
	)

inline

Apply an impulse to the center of mass. This immediately modifies the velocity.

Parameters

impulse	the world impulse vector, usually in N-seconds or kg-m/s.
wake	also wake up the body

◆ ApplyTorque()

void b2Body::ApplyTorque	(	float	torque,
		bool	wake
	)

inline

Apply a torque. This affects the angular velocity without affecting the linear velocity of the center of mass.

Parameters

torque	about the z-axis (out of the screen), usually in N-m.
wake	also wake up the body

◆ CreateFixture() [1/2]

b2Fixture * b2Body::CreateFixture ( const b2FixtureDef * def )

Creates a fixture and attach it to this body. Use this function if you need to set some fixture parameters, like friction. Otherwise you can create the fixture directly from a shape. If the density is non-zero, this function automatically updates the mass of the body. Contacts are not created until the next time step.

Parameters

def	the fixture definition.

Warning: This function is locked during callbacks.

◆ CreateFixture() [2/2]

b2Fixture * b2Body::CreateFixture	(	const b2Shape *	shape,
		float	density
	)

Creates a fixture from a shape and attach it to this body. This is a convenience function. Use b2FixtureDef if you need to set parameters like friction, restitution, user data, or filtering. If the density is non-zero, this function automatically updates the mass of the body.

Parameters

shape	the shape to be cloned.
density	the shape density (set to zero for static bodies).

Warning: This function is locked during callbacks.

◆ DestroyFixture()

void b2Body::DestroyFixture ( b2Fixture * fixture )

Destroy a fixture. This removes the fixture from the broad-phase and destroys all contacts associated with this fixture. This will automatically adjust the mass of the body if the body is dynamic and the fixture has positive density. All fixtures attached to a body are implicitly destroyed when the body is destroyed.

Parameters

fixture the fixture to be removed.

Warning: This function is locked during callbacks.

◆ GetAngle()

float b2Body::GetAngle ( ) const

inline

Get the angle in radians.

Returns: the current world rotation angle in radians.

◆ GetAngularVelocity()

float b2Body::GetAngularVelocity ( ) const

inline

Get the angular velocity.

Returns: the angular velocity in radians/second.

◆ GetContactList()

b2ContactEdge * b2Body::GetContactList ( )

inline

Get the list of all contacts attached to this body.

Warning: this list changes during the time step and you may miss some collisions if you don't use b2ContactListener.

◆ GetInertia()

float b2Body::GetInertia ( ) const

inline

Get the rotational inertia of the body about the local origin.

Returns: the rotational inertia, usually in kg-m^2.

◆ GetLinearVelocity()

const b2Vec2 & b2Body::GetLinearVelocity ( ) const

inline

Get the linear velocity of the center of mass.

Returns: the linear velocity of the center of mass.

◆ GetLinearVelocityFromLocalPoint()

b2Vec2 b2Body::GetLinearVelocityFromLocalPoint ( const b2Vec2 & localPoint ) const

inline

Get the world velocity of a local point.

Parameters

localPoint a point in local coordinates.

Returns: the world velocity of a point.

◆ GetLinearVelocityFromWorldPoint()

b2Vec2 b2Body::GetLinearVelocityFromWorldPoint ( const b2Vec2 & worldPoint ) const

inline

Get the world linear velocity of a world point attached to this body.

Parameters

worldPoint a point in world coordinates.

Returns: the world velocity of a point.

◆ GetLocalPoint()

b2Vec2 b2Body::GetLocalPoint ( const b2Vec2 & worldPoint ) const

inline

Gets a local point relative to the body's origin given a world point.

Parameters

worldPoint a point in world coordinates.

Returns: the corresponding local point relative to the body's origin.

◆ GetLocalVector()

b2Vec2 b2Body::GetLocalVector ( const b2Vec2 & worldVector ) const

inline

Gets a local vector given a world vector.

Parameters

worldVector a vector in world coordinates.

Returns: the corresponding local vector.

◆ GetMass()

float b2Body::GetMass ( ) const

inline

Get the total mass of the body.

Returns: the mass, usually in kilograms (kg).

◆ GetMassData()

void b2Body::GetMassData ( b2MassData * data ) const

inline

Get the mass data of the body.

Returns: a struct containing the mass, inertia and center of the body.

◆ GetPosition()

const b2Vec2 & b2Body::GetPosition ( ) const

inline

Get the world body origin position.

Returns: the world position of the body's origin.

◆ GetTransform()

const b2Transform & b2Body::GetTransform ( ) const

inline

Get the body transform for the body's origin.

Returns: the world transform of the body's origin.

◆ GetWorldPoint()

b2Vec2 b2Body::GetWorldPoint ( const b2Vec2 & localPoint ) const

inline

Get the world coordinates of a point given the local coordinates.

Parameters

localPoint a point on the body measured relative the the body's origin.

Returns: the same point expressed in world coordinates.

◆ GetWorldVector()

b2Vec2 b2Body::GetWorldVector ( const b2Vec2 & localVector ) const

inline

Get the world coordinates of a vector given the local coordinates.

Parameters

localVector a vector fixed in the body.

Returns: the same vector expressed in world coordinates.

◆ IsAwake()

bool b2Body::IsAwake ( ) const

inline

Get the sleeping state of this body.

Returns: true if the body is awake.

◆ ResetMassData()

void b2Body::ResetMassData ( )

This resets the mass properties to the sum of the mass properties of the fixtures. This normally does not need to be called unless you called SetMassData to override the mass and you later want to reset the mass.

◆ SetAngularVelocity()

void b2Body::SetAngularVelocity ( float omega )

inline

Set the angular velocity.

Parameters

omega the new angular velocity in radians/second.

◆ SetAwake()

void b2Body::SetAwake ( bool flag )

inline

Set the sleep state of the body. A sleeping body has very low CPU cost.

Parameters

flag	set to true to wake the body, false to put it to sleep.

◆ SetEnabled()

void b2Body::SetEnabled ( bool flag )

Allow a body to be disabled. A disabled body is not simulated and cannot be collided with or woken up. If you pass a flag of true, all fixtures will be added to the broad-phase. If you pass a flag of false, all fixtures will be removed from the broad-phase and all contacts will be destroyed. Fixtures and joints are otherwise unaffected. You may continue to create/destroy fixtures and joints on disabled bodies. Fixtures on a disabled body are implicitly disabled and will not participate in collisions, ray-casts, or queries. Joints connected to a disabled body are implicitly disabled. An diabled body is still owned by a b2World object and remains in the body list.

◆ SetFixedRotation()

void b2Body::SetFixedRotation ( bool flag )

Set this body to have fixed rotation. This causes the mass to be reset.

◆ SetLinearVelocity()

void b2Body::SetLinearVelocity ( const b2Vec2 & v )

inline

Set the linear velocity of the center of mass.

Parameters

v	the new linear velocity of the center of mass.

◆ SetMassData()

void b2Body::SetMassData ( const b2MassData * data )

Set the mass properties to override the mass properties of the fixtures. Note that this changes the center of mass position. Note that creating or destroying fixtures can also alter the mass. This function has no effect if the body isn't dynamic.

Parameters

data	the mass properties.

◆ SetSleepingAllowed()

void b2Body::SetSleepingAllowed ( bool flag )

inline

You can disable sleeping on this body. If you disable sleeping, the body will be woken.

◆ SetTransform()

void b2Body::SetTransform	(	const b2Vec2 &	position,
		float	angle
	)

Set the position of the body's origin and rotation. Manipulating a body's transform may cause non-physical behavior. Note: contacts are updated on the next call to b2World::Step.

Parameters

position	the world position of the body's local origin.
angle	the world rotation in radians.

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

include/box2d/b2_body.h

Public Member Functions

Friends

Detailed Description

Member Function Documentation

◆ ApplyAngularImpulse()

◆ ApplyForce()

◆ ApplyForceToCenter()

◆ ApplyLinearImpulse()

◆ ApplyLinearImpulseToCenter()

◆ ApplyTorque()

◆ CreateFixture() [1/2]

◆ CreateFixture() [2/2]

◆ DestroyFixture()

◆ GetAngle()

◆ GetAngularVelocity()

◆ GetContactList()

◆ GetInertia()

◆ GetLinearVelocity()

◆ GetLinearVelocityFromLocalPoint()

◆ GetLinearVelocityFromWorldPoint()

◆ GetLocalPoint()

◆ GetLocalVector()

◆ GetMass()

◆ GetMassData()

◆ GetPosition()

◆ GetTransform()

◆ GetWorldPoint()

◆ GetWorldVector()

◆ IsAwake()

◆ ResetMassData()

◆ SetAngularVelocity()

◆ SetAwake()

◆ SetEnabled()

◆ SetFixedRotation()

◆ SetLinearVelocity()

◆ SetMassData()

◆ SetSleepingAllowed()

◆ SetTransform()