An PhysicsWorld2D object simulates collisions and other physical properties. More...

Public Member Functions
bool	isGlobalEventEnabled (ContactEventBits events) const
	Check whether specific collision events are globally enabled in this physics world.
void	setGlobalEventEnabled (ContactEventBits events, bool enabled)
	Enable or disable specific collision events globally in this physics world.
void	setPreSolveCallback (PreSolveCallback cb)
	Set the PreSolve callback for the 2D physics world.
void	rayCast (RayCastHitCallback2D func, const Ray2D &ray, void *data=nullptr)
	Searches for physics shapes that intersects the ray.
void	overlapBox (PhysicsQueryCallback2D func, const Rect &rect, void *data)
	f Enumerates all physics shapes whose bounding box overlaps the specified rectangle.
Collider2D *	overlapBox (const Rect &rect) const
	Returns the nearest physics shape whose bounding box overlaps the specified rectangle.
Vector< Collider2D * >	overlapBoxAll (const Rect &rect) const
	Returns all physics shapes whose bounding box overlaps the specified rectangle.
void	overlapPoint (PhysicsQueryCallback2D func, const Vec2 &point, void *data)
	Enumerates all physics shapes that contain the specified point.
Collider2D *	overlapPoint (const Vec2 &point) const
	Returns the nearest physics shape that contains the specified point.
Vector< Collider2D * >	overlapPointAll (const Vec2 &point) const
	Returns all physics shapes that contain the specified point.
Scene *	getScene () const
	Get a scene contain this physics world.
Vec2	getGravity () const
	Get the gravity value of this physics world.
void	setGravity (const Vec2 &gravity)
	set the gravity value of this physics world.
void	setSpeed (float speed)
	Set the speed of this physics world.
float	getSpeed ()
	Get the speed of this physics world.
void	setSubsteps (int steps)
	set the number of substeps in an update of the physics world.
int	getSubsteps () const
	Get the number of substeps of this physics world.
void	setPreUpdateCallback (const std::function< void()> &callback)
	set the callback which invoked before update of each object in physics world.
void	setPostUpdateCallback (const std::function< void()> &callback)
	set the callback which invoked after update of each object in physics world.
void	setAutoStep (bool autoStep)
	To control the step of physics.
bool	isAutoStep ()
	Get the auto step of this physics world.
void	stepSimulation (float delta)
	Advances the physics simulation by one step.

Static Public Attributes
static const int	DEBUGDRAW_NONE
	draw nothing
static const int	DEBUGDRAW_SHAPE
	draw shapes
static const int	DEBUGDRAW_JOINT
	draw joints
static const int	DEBUGDRAW_CONTACT
	draw contact
static const int	DEBUGDRAW_ALL
	draw all

Detailed Description

An PhysicsWorld2D object simulates collisions and other physical properties.

You do not create PhysicsWorld2D objects directly; instead, you can get it from an Scene object.

Member Function Documentation

◆ isGlobalEventEnabled()

bool isGlobalEventEnabled ( ContactEventBits events ) const

Check whether specific collision events are globally enabled in this physics world.

This method verifies if the given event bits are allowed by the world's global event mask. Even if a collider enables these events locally, they will only take effect if the world also permits them.

Parameters

events Collision event bits to check.

Returns: True if all specified events are enabled globally, false otherwise.

◆ setGlobalEventEnabled()

void setGlobalEventEnabled	(	ContactEventBits	events,
		bool	enabled )

Enable or disable specific collision events globally in this physics world.

This modifies the world's global event mask by turning on or off the specified event bits. Colliders can only generate these events if they are enabled both locally and globally.

Note: This setting should be applied before any rigid-body components are added to nodes, because global event state cannot be changed at runtime once rigidbodies are active. By default, all global collision events are disabled (mask = 0).

Parameters

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

◆ setPreSolveCallback()

void setPreSolveCallback ( PreSolveCallback cb )

Set the PreSolve callback for the 2D physics world.

The PreSolve callback is invoked before constraint resolution, allowing the user to decide whether a contact should be accepted or rejected. This mimics Box2D-style PreSolve behavior.

Parameters

cb	User-provided callback function with signature: bool(const ContactInfo2D&) Return true to accept the contact. Return false to reject the contact.

Warning

PreSolve callbacks are potentially dangerous:

Avoid race conditions and shared state modifications.
Do not perform blocking or long-running operations.
Execution order of multiple callbacks is not guaranteed, which may lead to non-deterministic behavior.

Note: If no callback is set, all contacts are accepted by default.

◆ rayCast()

void rayCast	(	RayCastHitCallback2D	func,
		const Ray2D &	ray,
		void *	data = nullptr )

Searches for physics shapes that intersects the ray.

Query this physics world along the line segment from start to end.

Parameters

func	Func is called for each shape found.
start	A Vec2 object contains the begin position of the ray.
end	A Vec2 object contains the end position of the ray.
data	User defined data, it is passed to func.

◆ overlapBox() [1/2]

void overlapBox	(	PhysicsQueryCallback2D	func,
		const Rect &	rect,
		void *	data )

f Enumerates all physics shapes whose bounding box overlaps the specified rectangle.

Queries the physics world for shapes intersecting the given rect. For each overlapping shape, the provided callback function is invoked.

Parameters

func	Callback function executed for each overlapping shape.
rect	Rectangle region (x, y, width, height) used for overlap testing.
data	User-defined data passed to the callback.

◆ overlapBox() [2/2]

Collider2D * overlapBox ( const Rect & rect ) const

Returns the nearest physics shape whose bounding box overlaps the specified rectangle.

Queries the physics world at the given rect and finds the closest shape that intersects it. If no shape overlaps the rect, nullptr is returned.

Parameters

rect	Rectangle region (x, y, width, height) used for overlap testing.

Returns: Pointer to the nearest Collider2D overlapping the rect, or nullptr if none were found.

◆ overlapBoxAll()

Vector< Collider2D * > overlapBoxAll ( const Rect & rect ) const

Returns all physics shapes whose bounding box overlaps the specified rectangle.

Queries the physics world and collects every shape intersecting the given rect into a vector.

Parameters

rect	Rectangle region (x, y, width, height) used for overlap testing.

Returns: A vector of Collider2D pointers representing all shapes overlapping the rect.

◆ overlapPoint() [1/2]

void overlapPoint	(	PhysicsQueryCallback2D	func,
		const Vec2 &	point,
		void *	data )

Enumerates all physics shapes that contain the specified point.

Queries the physics world for shapes covering the given point. For each shape that contains the point, the provided callback function is invoked.

Attention: The point must lie inside at least one shape to trigger callbacks.

Parameters

func	Callback function executed for each shape containing the point.
point	Position of the point to test.
data	User-defined data passed to the callback.

◆ overlapPoint() [2/2]

Collider2D * overlapPoint ( const Vec2 & point ) const

Returns the nearest physics shape that contains the specified point.

Queries the physics world at the given point and finds the closest shape that covers it. If no shape contains the point, nullptr is returned.

Parameters

point Position of the point to test.

Returns: Pointer to the nearest Collider2D containing the point, or nullptr if none were found.

◆ overlapPointAll()

Vector< Collider2D * > overlapPointAll ( const Vec2 & point ) const

Returns all physics shapes that contain the specified point.

Queries the physics world and collects every shape covering the given point into a vector.

Attention: The point must lie inside at least one shape to produce results.

Parameters

point Position of the point to test.

Returns: A vector of Collider2D pointers representing all shapes that contain the point.

◆ getScene()

Scene * getScene ( ) const

inline

Get a scene contain this physics world.

Attention: This value is initialized in constructor

Returns: A Scene object reference.

◆ getGravity()

Vec2 getGravity ( ) const

inline

Get the gravity value of this physics world.

Returns: A Vec2 object.

◆ setGravity()

void setGravity ( const Vec2 & gravity )

set the gravity value of this physics world.

Parameters

gravity A gravity value of this physics world.

◆ setSpeed()

void setSpeed ( float speed )

inline

Set the speed of this physics world.

Attention: if you setAutoStep(false), this won't work.

Parameters

speed A float number. Speed is the rate at which the simulation executes. default value is 1.0.

◆ getSpeed()

float getSpeed ( )

inline

Get the speed of this physics world.

Returns: A float number.

◆ setSubsteps()

void setSubsteps ( int steps )

set the number of substeps in an update of the physics world.

One physics update will be divided into several substeps to increase its accuracy.

Parameters

steps An integer number, default value is 1.

◆ getSubsteps()

int getSubsteps ( ) const

inline

Get the number of substeps of this physics world.

Returns: An integer number.

◆ setAutoStep()

void setAutoStep ( bool autoStep )

inline

To control the step of physics.

If you want control it by yourself( fixed-timestep for example ), you can set this to false and call step by yourself.

Attention: If you set auto step to false, setSpeed setSubsteps won't works, you need to control the time step by yourself.

Parameters

autoStep A bool object, default value is true.

◆ isAutoStep()

bool isAutoStep ( )

inline

Get the auto step of this physics world.

Returns: A bool object.

◆ stepSimulation()

void stepSimulation ( float delta )

Advances the physics simulation by one step.

By default, the physics world runs with auto-step enabled, and this function is called automatically each frame. If you disable auto-step via setAutoStep(false), you must call this function manually to update the simulation.

Parameters

delta The time step (in seconds) to simulate.

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

PhysicsWorld2D.h

Public Member Functions

Static Public Attributes

Detailed Description

Member Function Documentation

◆ isGlobalEventEnabled()

◆ setGlobalEventEnabled()

◆ setPreSolveCallback()

◆ rayCast()

◆ overlapBox() [1/2]

◆ overlapBox() [2/2]

◆ overlapBoxAll()

◆ overlapPoint() [1/2]

◆ overlapPoint() [2/2]

◆ overlapPointAll()

◆ getScene()

◆ getGravity()

◆ setGravity()

◆ setSpeed()

◆ getSpeed()

◆ setSubsteps()

◆ getSubsteps()

◆ setAutoStep()

◆ isAutoStep()

◆ stepSimulation()