RigidBody2D

Inherits: PhysicsBody2D < CollisionObject2D < Node2D < CanvasItem < Node < Object

A body that is controlled by the 2D physics engine.

Description

This node implements simulated 2D physics. You do not control a RigidBody2D directly. Instead you apply forces to it (gravity, impulses, etc.) and the physics simulation calculates the resulting movement based on its mass, friction, and other physical properties.

A RigidBody2D has 4 behavior modes: Rigid, Static, Character, and Kinematic.

Note: You should not change a RigidBody2D's position or linear_velocity every frame or even very often. If you need to directly affect the body's state, use _integrate_forces, which allows you to directly access the physics state.

Please also keep in mind that physics bodies manage their own transform which overwrites the ones you set. So any direct or indirect transformation (including scaling of the node or its parent) will be visible in the editor only, and immediately reset at runtime.

If you need to override the default physics behavior or add a transformation at runtime, you can write a custom force integration. See custom_integrator.

The center of mass is always located at the node's origin without taking into account the CollisionShape2D centroid offsets.

Properties

float	angular_damp	-1.0
float	angular_velocity	0.0
Vector2	applied_force	Vector2( 0, 0 )
float	applied_torque	0.0
float	bounce
bool	can_sleep	true
bool	contact_monitor	false
int	contacts_reported	0
CCDMode	continuous_cd	0
bool	custom_integrator	false
float	friction
float	gravity_scale	1.0
float	inertia
float	linear_damp	-1.0
Vector2	linear_velocity	Vector2( 0, 0 )
float	mass	1.0
Mode	mode	0
PhysicsMaterial	physics_material_override
bool	sleeping	false
float	weight	9.8

Methods

void	_integrate_forces ( Physics2DDirectBodyState state ) virtual
void	add_central_force ( Vector2 force )
void	add_force ( Vector2 offset, Vector2 force )
void	add_torque ( float torque )
void	apply_central_impulse ( Vector2 impulse )
void	apply_impulse ( Vector2 offset, Vector2 impulse )
void	apply_torque_impulse ( float torque )
Array	get_colliding_bodies ( ) const
void	set_axis_velocity ( Vector2 axis_velocity )
bool	test_motion ( Vector2 motion, bool infinite_inertia=true, float margin=0.08, Physics2DTestMotionResult result=null )

Signals

body_entered ( Node body )

Emitted when a body enters into contact with this one. Requires contact_monitor to be set to true and contacts_reported to be set high enough to detect all the collisions.

body_exited ( Node body )

Emitted when a body exits contact with this one. Requires contact_monitor to be set to true and contacts_reported to be set high enough to detect all the collisions.

body_shape_entered ( int body_id, Node body, int body_shape, int local_shape )

Emitted when a body enters into contact with this one. Reports colliding shape information. See CollisionObject2D for shape index information. Requires contact_monitor to be set to true and contacts_reported to be set high enough to detect all the collisions.

body_shape_exited ( int body_id, Node body, int body_shape, int local_shape )

Emitted when a body shape exits contact with this one. Reports colliding shape information. See CollisionObject2D for shape index information. Requires contact_monitor to be set to true and contacts_reported to be set high enough to detect all the collisions.

sleeping_state_changed ( )

Emitted when the physics engine changes the body's sleeping state.

Note: Changing the value sleeping will not trigger this signal. It is only emitted if the sleeping state is changed by the physics engine or emit_signal("sleeping_state_changed") is used.

Enumerations

enum Mode:

• MODE_RIGID = 0 --- Rigid mode. The body behaves as a physical object. It collides with other bodies and responds to forces applied to it. This is the default mode.
• MODE_STATIC = 1 --- Static mode. The body behaves like a StaticBody2D and does not move.
• MODE_CHARACTER = 2 --- Character mode. Similar to MODE_RIGID, but the body can not rotate.
• MODE_KINEMATIC = 3 --- Kinematic mode. The body behaves like a KinematicBody2D, and must be moved by code.

enum CCDMode:

• CCD_MODE_DISABLED = 0 --- Continuous collision detection disabled. This is the fastest way to detect body collisions, but can miss small, fast-moving objects.
• CCD_MODE_CAST_RAY = 1 --- Continuous collision detection enabled using raycasting. This is faster than shapecasting but less precise.
• CCD_MODE_CAST_SHAPE = 2 --- Continuous collision detection enabled using shapecasting. This is the slowest CCD method and the most precise.

Property Descriptions

float angular_damp

Default	-1.0
Setter	set_angular_damp(value)
Getter	get_angular_damp()

Damps the body's angular_velocity. If -1, the body will use the Default Angular Damp defined in Project > Project Settings > Physics > 2d.

float angular_velocity

Default	0.0
Setter	set_angular_velocity(value)
Getter	get_angular_velocity()

The body's rotational velocity.

Vector2 applied_force

Default	Vector2( 0, 0 )
Setter	set_applied_force(value)
Getter	get_applied_force()

The body's total applied force.

float applied_torque

Default	0.0
Setter	set_applied_torque(value)
Getter	get_applied_torque()

The body's total applied torque.

float bounce

Setter	set_bounce(value)
Getter	get_bounce()

The body's bounciness. Values range from 0 (no bounce) to 1 (full bounciness).

Deprecated, use PhysicsMaterial.bounce instead via physics_material_override.

bool can_sleep

Default	true
Setter	set_can_sleep(value)
Getter	is_able_to_sleep()

If true, the body can enter sleep mode when there is no movement. See sleeping.

Note: A RigidBody2D will never enter sleep mode automatically if its mode is MODE_CHARACTER. It can still be put to sleep manually by setting its sleeping property to true.

bool contact_monitor

Default	false
Setter	set_contact_monitor(value)
Getter	is_contact_monitor_enabled()

If true, the body will emit signals when it collides with another RigidBody2D. See also contacts_reported.

int contacts_reported

Default	0
Setter	set_max_contacts_reported(value)
Getter	get_max_contacts_reported()

The maximum number of contacts that will be recorded. Requires contact_monitor to be set to true.

Note: The number of contacts is different from the number of collisions. Collisions between parallel edges will result in two contacts (one at each end), and collisions between parallel faces will result in four contacts (one at each corner).

CCDMode continuous_cd

Default	0
Setter	set_continuous_collision_detection_mode(value)
Getter	get_continuous_collision_detection_mode()

Continuous collision detection mode.

Continuous collision detection tries to predict where a moving body will collide instead of moving it and correcting its movement after collision. Continuous collision detection is slower, but more precise and misses fewer collisions with small, fast-moving objects. Raycasting and shapecasting methods are available. See CCDMode for details.

bool custom_integrator

Default	false
Setter	set_use_custom_integrator(value)
Getter	is_using_custom_integrator()

If true, internal force integration is disabled for this body. Aside from collision response, the body will only move as determined by the _integrate_forces function.

float friction

Setter	set_friction(value)
Getter	get_friction()

The body's friction. Values range from 0 (frictionless) to 1 (maximum friction).

Deprecated, use PhysicsMaterial.friction instead via physics_material_override.

float gravity_scale

Default	1.0
Setter	set_gravity_scale(value)
Getter	get_gravity_scale()

Multiplies the gravity applied to the body. The body's gravity is calculated from the Default Gravity value in Project > Project Settings > Physics > 2d and/or any additional gravity vector applied by Area2Ds.

float inertia

Setter	set_inertia(value)
Getter	get_inertia()

The body's moment of inertia. This is like mass, but for rotation: it determines how much torque it takes to rotate the body. The moment of inertia is usually computed automatically from the mass and the shapes, but this function allows you to set a custom value. Set 0 inertia to return to automatically computing it.

float linear_damp

Default	-1.0
Setter	set_linear_damp(value)
Getter	get_linear_damp()

Damps the body's linear_velocity. If -1, the body will use the Default Linear Damp in Project > Project Settings > Physics > 2d.

Vector2 linear_velocity

Default	Vector2( 0, 0 )
Setter	set_linear_velocity(value)
Getter	get_linear_velocity()

The body's linear velocity.

float mass

Default	1.0
Setter	set_mass(value)
Getter	get_mass()

The body's mass.

Mode mode

Default	0
Setter	set_mode(value)
Getter	get_mode()

The body's mode. See Mode for possible values.

PhysicsMaterial physics_material_override

Setter	set_physics_material_override(value)
Getter	get_physics_material_override()

The physics material override for the body.

If a material is assigned to this property, it will be used instead of any other physics material, such as an inherited one.

bool sleeping

Default	false
Setter	set_sleeping(value)
Getter	is_sleeping()

If true, the body will not move and will not calculate forces until woken up by another body through, for example, a collision, or by using the apply_impulse or add_force methods.

float weight

Default	9.8
Setter	set_weight(value)
Getter	get_weight()

The body's weight based on its mass and the Default Gravity value in Project > Project Settings > Physics > 2d.

Method Descriptions

void _integrate_forces ( Physics2DDirectBodyState state ) virtual

Allows you to read and safely modify the simulation state for the object. Use this instead of Node._physics_process if you need to directly change the body's position or other physics properties. By default, it works in addition to the usual physics behavior, but custom_integrator allows you to disable the default behavior and write custom force integration for a body.

void add_central_force ( Vector2 force )

Adds a constant directional force without affecting rotation.

void add_force ( Vector2 offset, Vector2 force )

Adds a positioned force to the body. Both the force and the offset from the body origin are in global coordinates.

void add_torque ( float torque )

Adds a constant rotational force.

void apply_central_impulse ( Vector2 impulse )

Applies a directional impulse without affecting rotation.

void apply_impulse ( Vector2 offset, Vector2 impulse )

Applies a positioned impulse to the body. An impulse is time-independent! Applying an impulse every frame would result in a framerate-dependent force. For this reason it should only be used when simulating one-time impacts (use the "_force" functions otherwise). The position uses the rotation of the global coordinate system, but is centered at the object's origin.

void apply_torque_impulse ( float torque )

Applies a rotational impulse to the body.

Array get_colliding_bodies ( ) const

Returns a list of the bodies colliding with this one. Requires contact_monitor to be set to true and contacts_reported to be set high enough to detect all the collisions.

Note: The result of this test is not immediate after moving objects. For performance, list of collisions is updated once per frame and before the physics step. Consider using signals instead.

void set_axis_velocity ( Vector2 axis_velocity )

Sets the body's velocity on the given axis. The velocity in the given vector axis will be set as the given vector length. This is useful for jumping behavior.

bool test_motion ( Vector2 motion, bool infinite_inertia=true, float margin=0.08, Physics2DTestMotionResult result=null )

Returns true if a collision would result from moving in the given vector. margin increases the size of the shapes involved in the collision detection, and result is an object of type Physics2DTestMotionResult, which contains additional information about the collision (should there be one).