A physical entity that exists within a World. More...

#include <Body.hpp>

Public Types
using	Fixtures = std::forward_list< Fixture * >

using	Joints = std::unordered_set< Joint * >

using	Contacts = std::list< Contact * >

Public Member Functions
Fixture *	CreateFixture (std::shared_ptr< const Shape > shape, const FixtureDef &def=GetDefaultFixtureDef(), bool resetMassData=true)
	Creates a fixture and attaches it to this body. More...

bool	DestroyFixture (Fixture *fixture, bool resetMassData=true)
	Destroys a fixture. More...

void	SetTransform (const Length2D position, Angle angle)
	Sets the position of the body's origin and rotation. More...

Transformation	GetTransformation () const noexcept
	Gets the body transform for the body's origin. More...

Length2D	GetLocation () const noexcept
	Gets the world body origin location. More...

const Sweep &	GetSweep () const noexcept

Angle	GetAngle () const noexcept
	Get the angle in radians. More...

Length2D	GetWorldCenter () const noexcept
	Get the world position of the center of mass. More...

Length2D	GetLocalCenter () const noexcept
	Gets the local position of the center of mass. More...

Velocity	GetVelocity () const noexcept

void	SetVelocity (const Velocity &v) noexcept
	Sets the body's velocity (linear and angular velocity). More...

void	SetAcceleration (const LinearAcceleration2D linear, const AngularAcceleration angular) noexcept
	Sets the linear and rotational accelerations on this body. More...

LinearAcceleration2D	GetLinearAcceleration () const noexcept

AngularAcceleration	GetAngularAcceleration () const noexcept

InvMass	GetInvMass () const noexcept
	Gets the inverse total mass of the body. More...

InvRotInertia	GetInvRotInertia () const noexcept
	Gets the inverse rotational inertia of the body. More...

void	SetMassData (const MassData &data)
	Set the mass properties to override the mass properties of the fixtures. More...

void	ResetMassData ()
	Resets the mass data properties. More...

RealNum	GetLinearDamping () const noexcept
	Get the linear damping of the body. More...

void	SetLinearDamping (RealNum linearDamping) noexcept
	Set the linear damping of the body. More...

RealNum	GetAngularDamping () const noexcept
	Get the angular damping of the body. More...

void	SetAngularDamping (RealNum angularDamping) noexcept
	Set the angular damping of the body. More...

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

BodyType	GetType () const noexcept
	Get the type of this body. More...

bool	IsSpeedable () const noexcept
	Is "speedable". More...

bool	IsAccelerable () const noexcept
	Is accelerable. More...

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

bool	IsImpenetrable () const noexcept
	Is this body treated like a bullet for continuous collision detection? More...

void	SetSleepingAllowed (bool flag) noexcept
	You can disable sleeping on this body. If you disable sleeping, the body will be woken. More...

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

void	SetAwake () noexcept
	Sets this body to awake if it's a "speedable" body. More...

void	UnsetAwake () noexcept
	Sets this body to asleep if sleeping is allowed. More...

bool	IsAwake () const noexcept
	Gets the awake/asleep state of this body. More...

Time	GetUnderActiveTime () const noexcept
	Gets this body's under-active time value. More...

void	SetUnderActiveTime (Time value) noexcept
	Sets the "under-active" time to the given value. More...

void	SetEnabled (bool flag)
	Set the enabled state of the body. 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. A disabled body is still owned by a World object and remains in the body list. More...

bool	IsEnabled () const noexcept
	Get the enabled/disabled state of the body. More...

void	SetFixedRotation (bool flag)
	Set this body to have fixed rotation. This causes the mass to be reset. More...

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

const Fixtures &	GetFixtures () const noexcept
	Gets the container of all fixtures attached to this body. More...

const Joints &	GetJoints () const noexcept
	Gets the container of all joints attached to this body. More...

const Contacts &	GetContacts () const noexcept
	Gets the container of all contacts attached to this body. More...

void *	GetUserData () const noexcept
	Get the user data pointer that was provided in the body definition. More...

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

World *	GetWorld () noexcept
	Gets the parent world of this body. More...

const World *	GetWorld () const noexcept
	Gets the parent world of this body. More...

bool	IsMassDataDirty () const noexcept

Static Public Member Functions
static bool	IsValid (const Shape &shape)

Static Public Attributes
static constexpr auto	InvalidIslandIndex = static_cast<body_count_t>(-1)

Friends
class	BodyAtty

Detailed Description

A physical entity that exists within a World.

A rigid body entity created or destroyed through a World instance.

Invariant: Only bodies that allow sleeping, can be put to sleep.; Only "speedable" bodies can be awake.; Only "speedable" bodies can have non-zero velocities.; Only "accelerable" bodies can have non-zero accelerations.; Only "accelerable" bodies can have non-zero "under-active" times.

Note: Create these using the World::Create method.; On a 64-bit architecture with 4-byte RealNum, this data structure is at least 192-bytes large.

Member Typedef Documentation

◆ Contacts

using box2d::Body::Contacts = std::list<Contact*>

◆ Fixtures

using box2d::Body::Fixtures = std::forward_list<Fixture*>

◆ Joints

using box2d::Body::Joints = std::unordered_set<Joint*>

Member Function Documentation

◆ CreateFixture()

Fixture * Body::CreateFixture	(	std::shared_ptr< const Shape >	shape,
		const FixtureDef &	def = `GetDefaultFixtureDef()`,
		bool	resetMassData = `true`
	)

Creates a fixture and attaches it to this body.

Parameters

shape	Sharable shape definition. Its vertex radius must be less than the minimum or more than the maximum allowed by the body's world.
def	Initial fixture settings. Friction and density must be >= 0. Restitution must be > -infinity and < infinity.
resetMassData	Whether or not to reset the mass data of the body.

Note: This function should not be called if the world is locked.

Warning: This function is locked during callbacks.

Returns: nullptr if the world is locked or a parameter is dissallowed. A pointer to the created fixture otherwise.

◆ DestroyFixture()

bool Body::DestroyFixture	(	Fixture *	fixture,
		bool	resetMassData = `true`
	)

Destroys a fixture.

This removes the fixture from the broad-phase and destroys all contacts associated with this fixture. All fixtures attached to a body are implicitly destroyed when the body is destroyed.

Warning: This function is locked during callbacks.

Note: Make sure to explicitly call ResetMassData after fixtures have been destroyed.

See also: ResetMassData.

Parameters

fixture	the fixture to be removed.
resetMassData	Whether or not to reset the mass data.

◆ GetAngle()

Angle box2d::Body::GetAngle ( ) const

inlinenoexcept

Get the angle in radians.

Returns: the current world rotation angle in radians.

◆ GetAngularAcceleration()

AngularAcceleration box2d::Body::GetAngularAcceleration ( ) const

inlinenoexcept

◆ GetAngularDamping()

RealNum box2d::Body::GetAngularDamping ( ) const

inlinenoexcept

Get the angular damping of the body.

◆ GetContacts()

const Body::Contacts & box2d::Body::GetContacts ( ) const

inlinenoexcept

Gets the container 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 ContactListener.

◆ GetFixtures()

const Body::Fixtures & box2d::Body::GetFixtures ( ) const

inlinenoexcept

Gets the container of all fixtures attached to this body.

◆ GetInvMass()

InvMass box2d::Body::GetInvMass ( ) const

inlinenoexcept

Gets the inverse total mass of the body.

This is the cached result of dividing 1 by the body's mass. Often floating division is much slower than multiplication. As such, it's likely faster to multiply values by this inverse value than to redivide them all the time by the mass.

Returns: Value of zero or more representing the body's inverse mass (in 1/kg).

See also: SetMassData.

◆ GetInvRotInertia()

InvRotInertia box2d::Body::GetInvRotInertia ( ) const

inlinenoexcept

Gets the inverse rotational inertia of the body.

This is the cached result of dividing 1 by the body's rotational inertia. Often floating division is much slower than multiplication. As such, it's likely faster to multiply values by this inverse value than to redivide them all the time by the rotational inertia.

Returns: Inverse rotational intertia (in 1/kg-m^2).

◆ GetJoints()

const Body::Joints & box2d::Body::GetJoints ( ) const

inlinenoexcept

Gets the container of all joints attached to this body.

◆ GetLinearAcceleration()

LinearAcceleration2D box2d::Body::GetLinearAcceleration ( ) const

inlinenoexcept

◆ GetLinearDamping()

RealNum box2d::Body::GetLinearDamping ( ) const

inlinenoexcept

Get the linear damping of the body.

◆ GetLocalCenter()

Length2D box2d::Body::GetLocalCenter ( ) const

inlinenoexcept

Gets the local position of the center of mass.

◆ GetLocation()

Length2D box2d::Body::GetLocation ( ) const

inlinenoexcept

Gets the world body origin location.

This is the location of the body's origin relative to its world. The location of the body after stepping the world's physics simulations is dependent on a number of factors:

Location at the last time step.
Forces acting on the body (gravity, applied force, applied impulse).
The mass data of the body.
Damping of the body.
Restitution and friction values of the body's fixtures when they experience collisions.
Returns
World location of the body's origin.

◆ GetSweep()

const Sweep & box2d::Body::GetSweep ( ) const

inlinenoexcept

◆ GetTransformation()

Transformation box2d::Body::GetTransformation ( ) const

inlinenoexcept

Gets the body transform for the body's origin.

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

◆ GetType()

BodyType box2d::Body::GetType ( ) const

inlinenoexcept

Get the type of this body.

◆ GetUnderActiveTime()

Time box2d::Body::GetUnderActiveTime ( ) const

inlinenoexcept

Gets this body's under-active time value.

Returns: Zero or more time in seconds (of step time) that this body has been "under-active" for.

◆ GetUserData()

void * box2d::Body::GetUserData ( ) const

inlinenoexcept

Get the user data pointer that was provided in the body definition.

◆ GetVelocity()

Velocity box2d::Body::GetVelocity ( ) const

inlinenoexcept

◆ GetWorld() [1/2]

World * box2d::Body::GetWorld ( )

inlinenoexcept

Gets the parent world of this body.

◆ GetWorld() [2/2]

const World * box2d::Body::GetWorld ( ) const

inlinenoexcept

Gets the parent world of this body.

◆ GetWorldCenter()

Length2D box2d::Body::GetWorldCenter ( ) const

inlinenoexcept

Get the world position of the center of mass.

◆ IsAccelerable()

bool box2d::Body::IsAccelerable ( ) const

inlinenoexcept

Is accelerable.

Indicates whether this body is accelerable, ie. whether it is effected by forces. Only Dynamic bodies are accelerable.

Returns: true if the body is accelerable, false otherwise.

◆ IsAwake()

bool box2d::Body::IsAwake ( ) const

inlinenoexcept

Gets the awake/asleep state of this body.

Warning: Being awake may or may not imply being speedable.

Returns: true if the body is awake.

◆ IsEnabled()

bool box2d::Body::IsEnabled ( ) const

inlinenoexcept

Get the enabled/disabled state of the body.

◆ IsFixedRotation()

bool box2d::Body::IsFixedRotation ( ) const

inlinenoexcept

Does this body have fixed rotation?

◆ IsImpenetrable()

bool box2d::Body::IsImpenetrable ( ) const

inlinenoexcept

Is this body treated like a bullet for continuous collision detection?

◆ IsMassDataDirty()

bool box2d::Body::IsMassDataDirty ( ) const

inlinenoexcept

◆ IsSleepingAllowed()

bool box2d::Body::IsSleepingAllowed ( ) const

inlinenoexcept

Is this body allowed to sleep.

◆ IsSpeedable()

bool box2d::Body::IsSpeedable ( ) const

inlinenoexcept

Is "speedable".

Is this body able to have a non-zero speed associated with it. Kinematic and Dynamic bodies are speedable. Static bodies are not.

◆ IsValid()

bool Body::IsValid ( const Shape & shape )

static

◆ ResetMassData()

void Body::ResetMassData ( )

Resets the mass data properties.

This resets the mass data to the sum of the mass properties of the fixtures.

Note: This method must be called after calling CreateFixture to update the body mass data properties unless SetMassData is used.

See also: SetMassData.

◆ SetAcceleration()

void Body::SetAcceleration	(	const LinearAcceleration2D	linear,
		const AngularAcceleration	angular
	)

noexcept

Sets the linear and rotational accelerations on this body.

Note: This has no effect on non-accelerable bodies.; A non-zero acceleration will also awaken the body.

Parameters

linear	Linear acceleration.
angular	Angular acceleration.

◆ SetAngularDamping()

void box2d::Body::SetAngularDamping ( RealNum angularDamping )

inlinenoexcept

Set the angular damping of the body.

◆ SetAwake()

void box2d::Body::SetAwake ( )

inlinenoexcept

Sets this body to awake if it's a "speedable" body.

This sets the sleep state of the body to awake if it's a "speedable" body. It has no effect otherwise.

Postcondition: If this body is a "speedable" body, then this body's IsAwake method returns true.

◆ SetBullet()

void box2d::Body::SetBullet ( bool flag )

inlinenoexcept

Should this body be treated like a bullet for continuous collision detection?

◆ SetEnabled()

void Body::SetEnabled ( bool flag )

Set the enabled state of the body. 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. A disabled body is still owned by a World object and remains in the body list.

◆ SetFixedRotation()

void Body::SetFixedRotation ( bool flag )

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

◆ SetLinearDamping()

void box2d::Body::SetLinearDamping ( RealNum linearDamping )

inlinenoexcept

Set the linear damping of the body.

◆ SetMassData()

void Body::SetMassData ( const MassData & data )

Set the mass properties to override the mass properties of the fixtures.

Note: This changes the center of mass position.; 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 box2d::Body::SetSleepingAllowed ( bool flag )

inlinenoexcept

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

◆ SetTransform()

void Body::SetTransform	(	const Length2D	position,
		Angle	angle
	)

Sets the position of the body's origin and rotation.

This instantly adjusts the body to be at the new position and new orientation.

Warning: Manipulating a body's transform may cause non-physical behavior.

Note: Contacts are updated on the next call to World::Step.

Parameters

position	Valid world position of the body's local origin. Behavior is undefined if value is invalid.
angle	Valid world rotation in radians. Behavior is undefined if value is invalid.

◆ SetType()

void Body::SetType ( BodyType type )

Set the type of this body. This may alter the mass and velocity.

◆ SetUnderActiveTime()

void box2d::Body::SetUnderActiveTime ( Time value )

inlinenoexcept

Sets the "under-active" time to the given value.

Sets the "under-active" time to a value of zero or a non-zero value if the body is "accelerable". Otherwise it does nothing.

Warning: Behavior is undefined for negative values.

Note: A non-zero time is only valid for an "accelerable" body.

◆ SetUserData()

void box2d::Body::SetUserData ( void * data )

inlinenoexcept

Set the user data. Use this to store your application specific data.

◆ SetVelocity()

void Body::SetVelocity ( const Velocity & v )

noexcept

Sets the body's velocity (linear and angular velocity).

Note: This method does nothing if this body is not speedable.; A non-zero velocity will awaken this body.

See also: SetAwake.; SetUnderActiveTime.

◆ UnsetAwake()

void box2d::Body::UnsetAwake ( )

inlinenoexcept

Sets this body to asleep if sleeping is allowed.

If this body is allowed to sleep, this: sets the sleep state of the body to asleep, resets this body's under active time, and resets this body's velocity (linear and angular).

Postcondition: This body's IsAwake method returns false.; This body's GetUnderActiveTime method returns zero.; This body's GetVelocity method returns zero linear and zero angular speed.

Friends And Related Function Documentation

◆ BodyAtty

friend class BodyAtty

friend

Member Data Documentation

◆ InvalidIslandIndex

constexpr auto box2d::Body::InvalidIslandIndex = static_cast<body_count_t>(-1)

static

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

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Friends

Detailed Description

Member Typedef Documentation

◆ Contacts

◆ Fixtures

◆ Joints

Member Function Documentation

◆ CreateFixture()

◆ DestroyFixture()

◆ GetAngle()

◆ GetAngularAcceleration()

◆ GetAngularDamping()

◆ GetContacts()

◆ GetFixtures()

◆ GetInvMass()

◆ GetInvRotInertia()

◆ GetJoints()

◆ GetLinearAcceleration()

◆ GetLinearDamping()

◆ GetLocalCenter()

◆ GetLocation()

◆ GetSweep()

◆ GetTransformation()

◆ GetType()

◆ GetUnderActiveTime()

◆ GetUserData()

◆ GetVelocity()

◆ GetWorld() [1/2]

◆ GetWorld() [2/2]

◆ GetWorldCenter()

◆ IsAccelerable()

◆ IsAwake()

◆ IsEnabled()

◆ IsFixedRotation()

◆ IsImpenetrable()

◆ IsMassDataDirty()

◆ IsSleepingAllowed()

◆ IsSpeedable()

◆ IsValid()

◆ ResetMassData()

◆ SetAcceleration()

◆ SetAngularDamping()

◆ SetAwake()

◆ SetBullet()

◆ SetEnabled()

◆ SetFixedRotation()

◆ SetLinearDamping()

◆ SetMassData()

◆ SetSleepingAllowed()

◆ SetTransform()

◆ SetType()

◆ SetUnderActiveTime()

◆ SetUserData()

◆ SetVelocity()

◆ UnsetAwake()

Friends And Related Function Documentation

◆ BodyAtty

Member Data Documentation

◆ InvalidIslandIndex