A Rigidbody2D affected by physics2d. More...

#include <Rigidbody2D.h>

Public Member Functions
virtual Collider2D *	addCollider (Collider2D *collider, bool addMassAndMoment=true)
	Add a collider to body.
void	removeCollider (Collider2D *collider, bool reduceMassAndMoment=true)
	Remove a collider from body.
void	removeCollider (int tag, bool reduceMassAndMoment=true)
	Remove a collider from body.
void	removeAllColliders (bool reduceMassAndMoment=true)
	Remove all colliders.
const Vector< Collider2D * > &	getColliders () const
	Get the body colliders.
Collider2D *	getFirstCollider () const
	Get the first collider of the body colliders.
Collider2D *	getCollider (int tag) const
	get the collider of the body.
virtual void	applyForce (const Vec2 &force, const Vec2 &offset=Vec2::zero)
	Applies a continuous force to body.
virtual void	resetForces ()
	reset all the force applied to body.
virtual void	applyImpulse (const Vec2 &impulse, const Vec2 &offset=Vec2::zero)
	Applies a immediate force to body.
virtual void	applyTorque (float torque)
	Applies a torque force to body.
virtual void	setVelocity (const Vec2 &velocity)
	Set the velocity of a body.
virtual Vec2	getVelocity ()
	Get the velocity of a body.
virtual void	setAngularVelocity (float velocity)
	Set the angular velocity in degrees of a body.
virtual Vec2	getVelocityAtLocalPoint (const Vec2 &point)
	Get the angular velocity of a body at a local point.
virtual Vec2	getVelocityAtWorldPoint (const Vec2 &point)
	get the angular velocity of a body at a world point
virtual float	getAngularVelocity ()
	get the angular velocity in degrees of a body
virtual void	setVelocityLimit (float limit)
	set the max of velocity
virtual float	getVelocityLimit ()
	get the max of velocity
virtual void	setAngularVelocityLimit (float limit)
	set the max of angular velocity in degrees
virtual float	getAngularVelocityLimit ()
	get the max of angular velocity in degrees
void	removeFromWorld ()
	remove the body from the world it added to
PhysicsWorld2D *	getWorld () const
	get the world body added to.
Node *	getNode () const
	get the node the body set to.
void	setEventEnabled (ContactEventBits events, bool enabled)
	Enable or disable one or more event types for this collider.
uint64_t	getCategoryBits () const
	Return bitmask of first collider.
void	setCategoryBits (uint64_t categoryBits)
	A mask that defines which categories this physics body belongs to.
int	getCollisionMaskBits () const
	Return bitmask of first collider.
void	setCollisionMaskBits (int maskBits)
	A mask that defines which categories of physics bodies can collide with this physics body.
void	setGroup (int groupIndex)
	Set the group of body.
int	getGroup () const
	Return group of first collider.
Vec2	getPosition () const
	get the body position.
float	getRotation ()
	get the body rotation in degrees.
void	setPositionOffset (const Vec2 &position)
	set body position offset, it's the position witch relative to node
const Vec2 &	getPositionOffset () const
	get body position offset.
void	setRotationOffset (float rotation)
	set body rotation offset in degrees, it's the rotation witch relative to node
float	getRotationOffset () const
	set the body rotation offset in degrees
void	setDynamic ()
	Sets the body type to dynamic (affected by forces, gravity, collisions).
bool	isDynamic () const
	Checks if the body type is dynamic.
void	setKinematic ()
	Sets the body type to kinematic (not affected by forces, moved by script/animation).
bool	isKinematic () const
	Checks if the body type is kinematic.
bool	getBodyType () const
	Get the body type.
void	setBodyType (BodyType bodyType)
	Set body type.
float	getMass () const
	Get the body mass.
void	setMass (float mass)
	Set the body mass Override the body's mass properties.
float	getMoment () const
	Get the body moment of rotation inertia.
void	setMoment (float moment)
	Set the body moment of rotation inertia.
float	getLinearDamping () const
	get linear damping.
void	setLinearDamping (float damping)
	Set linear damping.
float	getAngularDamping () const
	Get angular damping.
void	setAngularDamping (float damping)
	Set angular damping.
bool	isAttached () const
	Whether the body is attached to physics world.
CollisionDetectionMode	getCollisionDetectionMode () const
	Gets the current collision detection mode.
void	setCollisionDetectionMode (CollisionDetectionMode mode)
	Sets the collision detection mode.
void	setEnabled (bool enable) override
	Set the enable value.
bool	isRotationEnabled () const
	Whether the body can rotation.
void	setRotationEnabled (bool enabled)
	Set the body is allow rotation or not.
bool	isGravityEnabled () const
	Whether this physics body is affected by the physics world's gravitational force.
void	setGravityEnabled (bool enabled)
	Set the body is affected by the physics world's gravitational force or not.
void	setGravityScale (float scale)
	Sets the gravity scale factor.
float	getGravityScale () const
	Gets the current gravity scale factor.
void	setTag (unsigned int tag)
	Set this body's tag.
unsigned int	getTag () const
	Get this body's tag.
Vec2	world2Local (const Vec2 &point)
	Convert the world point to local.
Vec2	local2World (const Vec2 &point)
	Convert the local point to world.
float	getAngleRadians ()
	Gets angle in randius.
b2BodyId	internalHandle () const
	Get the rigid body of box2d.

Static Public Member Functions
static Rigidbody2D *	create ()
	Create a rigibody.
static Rigidbody2D *	createCircle (float radius, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT, const Vec2 &offset=Vec2::zero)
	Create a body contains a circle.
static Rigidbody2D *	createBox (const Vec2 &size, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT, const Vec2 &offset=Vec2::zero)
	Create a body contains a box collider.
static Rigidbody2D *	createPolygon (std::span< const Vec2 > points, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT, const Vec2 &offset=Vec2::zero)
	Create a body contains a polygon collider.
static Rigidbody2D *	createEdgeSegment (const Vec2 &a, const Vec2 &b, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT)
	Create a body contains a EdgeSegment collider.
static Rigidbody2D *	createEdgeBox (const Vec2 &size, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT, const Vec2 &offset=Vec2::zero)
	Create a body contains a EdgeBox collider.
static Rigidbody2D *	createEdgePolygon (std::span< const Vec2 > points, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT)
	Create a body contains a EdgePolygon collider.
static Rigidbody2D *	createEdgeChain (std::span< const Vec2 > points, const PhysicsMaterial2D &material=PHYSICS_MATERIAL_2D_DEFAULT)
	Create a body contains a EdgeChain collider.

Detailed Description

A Rigidbody2D affected by physics2d.

It can attach one or more colliders. By default, Box2D automatically computes mass and moment of inertia from the collider shapes and the specified density (default material PHYSICS_MATERIAL_2D_DEFAULT, density = 0.1f), using the formula: mass = density * area.

You can also set a body static/dynamic via setDynamic().

Note: Box2D does not allow changing mass or inertia dynamically once created.

Member Function Documentation

◆ create()

Rigidbody2D * create ( )

static

Create a rigibody.

The mass and moment automaticall computed by box2d internal

Returns: An autoreleased Rigidbody2D object pointer.

◆ createCircle()

Rigidbody2D * createCircle	(	float	radius,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT,
		const Vec2 &	offset = Vec2::zero )

static

Create a body contains a circle.

Parameters

radius	A float number, it is the circle's radius.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.
offset	A Vec2 object, it is the offset from the body's center of gravity in body local coordinates.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createBox()

Rigidbody2D * createBox	(	const Vec2 &	size,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT,
		const Vec2 &	offset = Vec2::zero )

static

Create a body contains a box collider.

Parameters

size	Size contains this box's width and height.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.
offset	A Vec2 object, it is the offset from the body's center of gravity in body local coordinates.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createPolygon()

Rigidbody2D * createPolygon	(	std::span< const Vec2 >	points,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT,
		const Vec2 &	offset = Vec2::zero )

static

Create a body contains a polygon collider.

Parameters

points	Points is an array of Vec2 structs defining a convex hull with a clockwise winding.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.
offset	A Vec2 object, it is the offset from the body's center of gravity in body local coordinates.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createEdgeSegment()

Rigidbody2D * createEdgeSegment	(	const Vec2 &	a,
		const Vec2 &	b,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT )

static

Create a body contains a EdgeSegment collider.

Parameters

a	It's the edge's begin position.
b	It's the edge's end position.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createEdgeBox()

Rigidbody2D * createEdgeBox	(	const Vec2 &	size,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT,
		const Vec2 &	offset = Vec2::zero )

static

Create a body contains a EdgeBox collider.

Parameters

size	The size contains this box's width and height.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.
offset	A Vec2 object, it is the offset from the body's center of gravity in body local coordinates.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createEdgePolygon()

Rigidbody2D * createEdgePolygon	(	std::span< const Vec2 >	points,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT )

static

Create a body contains a EdgePolygon collider.

Parameters

points	Points is an array of Vec2 structs defining a convex hull with a clockwise winding.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.

Returns: An autoreleased Rigidbody2D object pointer.

◆ createEdgeChain()

Rigidbody2D * createEdgeChain	(	std::span< const Vec2 >	points,
		const PhysicsMaterial2D &	material = PHYSICS_MATERIAL_2D_DEFAULT )

static

Create a body contains a EdgeChain collider.

Parameters

points	A Vec2 object pointer, it contains an array of points.
material	A PhysicsMaterial object, the default value is PHYSICSSHAPE_MATERIAL_DEFAULT.

Returns: An autoreleased Rigidbody2D object pointer.

◆ addCollider()

virtual Collider2D * addCollider	(	Collider2D *	collider,
		bool	addMassAndMoment = true )

virtual

Add a collider to body.

Parameters

collider	The collider to be added.
addMassAndMoment	If this is true, the collider's mass and moment will be added to body. The default is true.

Returns: This collider's pointer if added success or nullptr if failed.

◆ removeCollider() [1/2]

void removeCollider	(	Collider2D *	collider,
		bool	reduceMassAndMoment = true )

Remove a collider from body.

Parameters

collider	the collider to be removed.
reduceMassAndMoment	If this is true, the body mass and moment will be reduced by collider. The default is true.

◆ removeCollider() [2/2]

void removeCollider	(	int	tag,
		bool	reduceMassAndMoment = true )

Remove a collider from body.

Parameters

tag	The tag of the collider to be removed.
reduceMassAndMoment	If this is true, the body mass and moment will be reduced by collider. The default is true.

◆ removeAllColliders()

void removeAllColliders ( bool reduceMassAndMoment = true )

Remove all colliders.

Parameters

reduceMassAndMoment If this is true, the body mass and moment will be reduced by collider. The default is true.

◆ getColliders()

const Vector< Collider2D * > & getColliders ( ) const

inline

Get the body colliders.

Returns: A Vector<Collider2D*> object contains Collider2D pointer.

◆ getFirstCollider()

Collider2D * getFirstCollider ( ) const

inline

Get the first collider of the body colliders.

Returns: The first collider in this body.

◆ getCollider()

Collider2D * getCollider ( int tag ) const

get the collider of the body.

Parameters

tag	An integer number that identifies a Collider2D object.

Returns: A Collider2D object pointer or nullptr if no colliders were found.

◆ applyForce()

virtual void applyForce	(	const Vec2 &	force,
		const Vec2 &	offset = Vec2::zero )

virtual

Applies a continuous force to body.

Parameters

force	The force is applies to this body.
offset	A Vec2 object, it is the offset from the body's center of gravity in world coordinates.

◆ applyImpulse()

virtual void applyImpulse	(	const Vec2 &	impulse,
		const Vec2 &	offset = Vec2::zero )

virtual

Applies a immediate force to body.

Parameters

impulse	The impulse is applies to this body.
offset	A Vec2 object, it is the offset from the body's center of gravity in world coordinates.

◆ applyTorque()

virtual void applyTorque ( float torque )

virtual

Applies a torque force to body.

Parameters

torque The torque is applies to this body.

◆ setVelocity()

virtual void setVelocity ( const Vec2 & velocity )

virtual

Set the velocity of a body.

Parameters

velocity The velocity is set to this body.

◆ setAngularVelocity()

virtual void setAngularVelocity ( float velocity )

virtual

Set the angular velocity in degrees of a body.

Parameters

velocity The angular velocity is set to this body.

◆ setEventEnabled()

void setEventEnabled	(	ContactEventBits	events,
		bool	enabled )

Enable or disable one or more event types for this collider.

This method allows toggling specific event bits. You can enable or disable a single event or multiple events at once by combining flags.

Parameters

events	The event bits to modify.
enabled	True to enable the specified events, false to disable them.

◆ getCategoryBits()

uint64_t getCategoryBits ( ) const

Return bitmask of first collider.

Returns: If there is no collider in body, return default value.(0xFFFFFFFF)

◆ setCategoryBits()

void setCategoryBits ( uint64_t categoryBits )

A mask that defines which categories this physics body belongs to.

Every physics body in a scene can be assigned to up to 32 different categories, each corresponding to a bit in the bit mask. You define the mask values used in your game. In conjunction with the collisionBitMask and contactTestBitMask properties, you define which physics bodies interact with each other and when your game is notified of these interactions.

Parameters

categoryBits An integer number, the default value is UINT64_MAX (all bits set).

◆ getCollisionMaskBits()

int getCollisionMaskBits ( ) const

Return bitmask of first collider.

Returns: If there is no collider in body, return default value.(UINT64_MAX)

◆ setCollisionMaskBits()

void setCollisionMaskBits ( int maskBits )

A mask that defines which categories of physics bodies can collide with this physics body.

When two physics bodies contact each other, a collision may occur. This body's collision mask is compared to the other body's category mask by performing a logical AND operation. If the result is a non-zero value, then this body is affected by the collision. Each body independently chooses whether it wants to be affected by the other body. For example, you might use this to avoid collision calculations that would make negligible changes to a body's velocity.

Parameters

bitmask An integer number, the default value is UINT64_MAX (all bits set).

◆ setGroup()

void setGroup ( int groupIndex )

Set the group of body.

Collision groups let you specify an integral group index. You can have all fixtures with the same group index always collide (positive index) or never collide (negative index). It have high priority than bit masks.

◆ getGroup()

int getGroup ( ) const

Return group of first collider.

Returns: If there is no collider in body, return default value.(0)

◆ setMass()

void setMass ( float mass )

Set the body mass Override the body's mass properties.

Normally this is computed automatically using the shape geometry and density. This information is lost if a shape is added or removed or if the body type changes.

◆ setLinearDamping()

void setLinearDamping ( float damping )

inline

Set linear damping.

it is used to simulate fluid or air friction forces on the body.

Parameters

damping The value is 0.0f to 1.0f.

◆ setAngularDamping()

void setAngularDamping ( float damping )

inline

Set angular damping.

It is used to simulate fluid or air friction forces on the body.

Parameters

damping The value is 0.0f to 1.0f.

◆ setEnabled()

void setEnabled ( bool enable )

override

Set the enable value.

If the body it isn't enabled, it will not has simulation by world.

◆ setGravityScale()

void setGravityScale ( float scale )

Sets the gravity scale factor.

Parameters

scale Multiplier for global gravity (1.0 = normal gravity, 0 disables gravity).

◆ getGravityScale()

float getGravityScale ( ) const

inline

Gets the current gravity scale factor.

Returns: The multiplier applied to global gravity.

◆ setTag()

void setTag ( unsigned int tag )

inline

Set this body's tag.

Parameters

tag	An integer number that identifies a shape object.

◆ getTag()

unsigned int getTag ( ) const

inline

Get this body's tag.

Returns: An integer number.

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

Rigidbody2D.h

Public Member Functions

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ create()

◆ createCircle()

◆ createBox()

◆ createPolygon()

◆ createEdgeSegment()

◆ createEdgeBox()

◆ createEdgePolygon()

◆ createEdgeChain()

◆ addCollider()

◆ removeCollider() [1/2]

◆ removeCollider() [2/2]

◆ removeAllColliders()

◆ getColliders()

◆ getFirstCollider()

◆ getCollider()

◆ applyForce()

◆ applyImpulse()

◆ applyTorque()

◆ setVelocity()

◆ setAngularVelocity()

◆ setEventEnabled()

◆ getCategoryBits()

◆ setCategoryBits()

◆ getCollisionMaskBits()

◆ setCollisionMaskBits()

◆ setGroup()

◆ getGroup()

◆ setMass()

◆ setLinearDamping()

◆ setAngularDamping()

◆ setEnabled()

◆ setGravityScale()

◆ getGravityScale()

◆ setTag()

◆ getTag()