Inheritance #

RigidBody2D

- PhysicalBone2D
Table of contents

RigidBody2D #

is_instantiable, Node2D, Node, core, not_builtin_classes

A 2D physics body that is moved by a physics simulation.

RigidBody2D implements full 2D physics. It cannot be controlled directly, instead, you must apply forces to it (gravity, impulses, etc.), and the physics simulation will calculate the resulting movement, rotation, react to collisions, and affect other physics bodies in its path.

The body's behavior can be adjusted via lock_rotation, freeze, and freeze_mode. By changing various properties of the object, such as mass, you can control how the physics simulation acts on it.

A rigid body will always maintain its shape and size, even when forces are applied to it. It is useful for objects that can be interacted with in an environment, such as a tree that can be knocked over or a stack of crates that can be pushed around.

If you need to override the default physics behavior, you can write a custom force integration function. See custom_integrator.

Note: Changing the 2D transform or linear_velocity of a RigidBody2D very often may lead to some unpredictable behaviors. If you need to directly affect the body, prefer _integrate_forces as it allows you to directly access the physics state.

Members #

var angular_damp: float = 0.0#

Damps the body's rotation. By default, the body will use the ProjectSettings.physics/2d/default_angular_damp setting or any value override set by an Area2D the body is in. Depending on angular_damp_mode, you can set angular_damp to be added to or to replace the body's damping value.

See ProjectSettings.physics/2d/default_angular_damp for more details about damping.

var angular_damp_mode = DAMP_MODE_COMBINE#

Defines how angular_damp is applied. See DampMode for possible values.

var angular_velocity: float = 0.0#

The body's rotational velocity in radians per second.

var can_sleep: bool = true#

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

var center_of_mass: Vector2 = Vector2(0, 0)#

The body's custom center of mass, relative to the body's origin position, when center_of_mass_mode is set to CENTER_OF_MASS_MODE_CUSTOM. This is the balanced point of the body, where applied forces only cause linear acceleration. Applying forces outside of the center of mass causes angular acceleration.

When center_of_mass_mode is set to CENTER_OF_MASS_MODE_AUTO (default value), the center of mass is automatically computed.

var center_of_mass_mode = CENTER_OF_MASS_MODE_AUTO#

Defines the way the body's center of mass is set. See CenterOfMassMode for possible values.

var constant_force: Vector2 = Vector2(0, 0)#

The body's total constant positional forces applied during each physics update.

See add_constant_force and add_constant_central_force.

var constant_torque: float = 0.0#

The body's total constant rotational forces applied during each physics update.

See add_constant_torque.

var contact_monitor: bool = false#

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

Note: By default the maximum contacts reported is set to 0, meaning nothing will be recorded, see max_contacts_reported.

var continuous_cd = CCD_MODE_DISABLED#

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.

var custom_integrator: bool = false#

If true, the standard force integration (like gravity or damping) will be disabled for this body. Other than collision response, the body will only move as determined by the _integrate_forces method, if that virtual method is overridden.

Setting this property will call the method PhysicsServer2D.body_set_omit_force_integration internally.

var freeze: bool = false#

If true, the body is frozen. Gravity and forces are not applied anymore.

See freeze_mode to set the body's behavior when frozen.

For a body that is always frozen, use StaticBody2D or AnimatableBody2D instead.

var freeze_mode = FREEZE_MODE_STATIC#

The body's freeze mode. Can be used to set the body's behavior when freeze is enabled. See FreezeMode for possible values.

For a body that is always frozen, use StaticBody2D or AnimatableBody2D instead.

var gravity_scale: float = 1.0#

Multiplies the gravity applied to the body. The body's gravity is calculated from the ProjectSettings.physics/2d/default_gravity project setting and/or any additional gravity vector applied by Area2Ds.

var inertia: float = 0.0#

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 property allows you to set a custom value.

If set to 0, inertia is automatically computed (default value).

Note: This value does not change when inertia is automatically computed. Use PhysicsServer2D to get the computed inertia.

GDScript

@onready var ball = $Ball

func get_ball_inertia():
    return 1.0 / PhysicsServer2D.body_get_direct_state(ball.get_rid()).inverse_inertia

C#

private RigidBody2D _ball;

public override void _Ready()
{
    _ball = GetNode("Ball");
}

private float GetBallInertia()
{
    return 1.0f / PhysicsServer2D.BodyGetDirectState(_ball.GetRid()).InverseInertia;
}

var linear_damp: float = 0.0#

Damps the body's movement. By default, the body will use the ProjectSettings.physics/2d/default_linear_damp setting or any value override set by an Area2D the body is in. Depending on linear_damp_mode, you can set linear_damp to be added to or to replace the body's damping value.

See ProjectSettings.physics/2d/default_linear_damp for more details about damping.

var linear_damp_mode = DAMP_MODE_COMBINE#

Defines how linear_damp is applied. See DampMode for possible values.

var linear_velocity: Vector2 = Vector2(0, 0)#

The body's linear velocity in pixels per second. Can be used sporadically, but don't set this every frame, because physics may run in another thread and runs at a different granularity. Use _integrate_forces as your process loop for precise control of the body state.

var lock_rotation: bool = false#

If true, the body cannot rotate. Gravity and forces only apply linear movement.

var mass: float = 1.0#

The body's mass.

var max_contacts_reported: int = 0#

The maximum number of contacts that will be recorded. Requires a value greater than 0 and contact_monitor to be set to true to start to register contacts. Use get_contact_count to retrieve the count or get_colliding_bodies to retrieve bodies that have been collided with.

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).

var physics_material_override: PhysicsMaterial#

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.

var sleeping: bool = false#

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 apply_force methods.

Methods #

virtual func _integrate_forces(state: PhysicsDirectBodyState2D) -> void#

Called during physics processing, allowing you to read and safely modify the simulation state for the object. By default, it is called before the standard force integration, but the custom_integrator property allows you to disable the standard force integration and do fully custom force integration for a body.

func add_constant_central_force(force: Vector2) -> void#

Adds a constant directional force without affecting rotation that keeps being applied over time until cleared with constant_force = Vector2(0, 0).

This is equivalent to using add_constant_force at the body's center of mass.

func add_constant_force(position: Vector2 = Vector2(0, 0)) -> void#

Adds a constant positioned force to the body that keeps being applied over time until cleared with constant_force = Vector2(0, 0).

position is the offset from the body origin in global coordinates.

func add_constant_torque(torque: float) -> void#

Adds a constant rotational force without affecting position that keeps being applied over time until cleared with constant_torque = 0.

func apply_central_force(force: Vector2) -> void#

Applies a directional force without affecting rotation. A force is time dependent and meant to be applied every physics update.

This is equivalent to using apply_force at the body's center of mass.

func apply_central_impulse(impulse: Vector2 = Vector2(0, 0)) -> void#

Applies a directional impulse without affecting rotation.

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).

This is equivalent to using apply_impulse at the body's center of mass.

func apply_force(position: Vector2 = Vector2(0, 0)) -> void#

Applies a positioned force to the body. A force is time dependent and meant to be applied every physics update.

position is the offset from the body origin in global coordinates.

func apply_impulse(position: Vector2 = Vector2(0, 0)) -> void#

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).

position is the offset from the body origin in global coordinates.

func apply_torque(torque: float) -> void#

Applies a rotational force without affecting position. A force is time dependent and meant to be applied every physics update.

Note: inertia is required for this to work. To have inertia, an active CollisionShape2D must be a child of the node, or you can manually set inertia.

func apply_torque_impulse(torque: float) -> void#

Applies a rotational impulse to the body without affecting the position.

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).

Note: inertia is required for this to work. To have inertia, an active CollisionShape2D must be a child of the node, or you can manually set inertia.

const func get_colliding_bodies() -> Node2D[]#

Returns a list of the bodies colliding with this one. Requires contact_monitor to be set to true and max_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.

const func get_contact_count() -> int#

Returns the number of contacts this body has with other bodies. By default, this returns 0 unless bodies are configured to monitor contacts (see contact_monitor).

Note: To retrieve the colliding bodies, use get_colliding_bodies.

func set_axis_velocity(axis_velocity: Vector2) -> void#

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.

Annotations #

Constants #

const FREEZE_MODE_STATIC = 0 enum FreezeMode#

Static body freeze mode (default). The body is not affected by gravity and forces. It can be only moved by user code and doesn't collide with other bodies along its path.

const FREEZE_MODE_KINEMATIC = 1 enum FreezeMode#

Kinematic body freeze mode. Similar to FREEZE_MODE_STATIC, but collides with other bodies along its path when moved. Useful for a frozen body that needs to be animated.

const CENTER_OF_MASS_MODE_AUTO = 0 enum CenterOfMassMode#

In this mode, the body's center of mass is calculated automatically based on its shapes. This assumes that the shapes' origins are also their center of mass.

const CENTER_OF_MASS_MODE_CUSTOM = 1 enum CenterOfMassMode#

In this mode, the body's center of mass is set through center_of_mass. Defaults to the body's origin position.

const DAMP_MODE_COMBINE = 0 enum DampMode#

In this mode, the body's damping value is added to any value set in areas or the default value.

const DAMP_MODE_REPLACE = 1 enum DampMode#

In this mode, the body's damping value replaces any value set in areas or the default value.

const CCD_MODE_DISABLED = 0 enum CCDMode#

Continuous collision detection disabled. This is the fastest way to detect body collisions, but can miss small, fast-moving objects.

const CCD_MODE_CAST_RAY = 1 enum CCDMode#

Continuous collision detection enabled using raycasting. This is faster than shapecasting but less precise.

const CCD_MODE_CAST_SHAPE = 2 enum CCDMode#

Continuous collision detection enabled using shapecasting. This is the slowest CCD method and the most precise.

Constructors #

Enums #

FreezeMode#

enum FreezeMode { FREEZE_MODE_STATIC = 0, FREEZE_MODE_KINEMATIC = 1, }

CenterOfMassMode#

enum CenterOfMassMode { CENTER_OF_MASS_MODE_AUTO = 0, CENTER_OF_MASS_MODE_CUSTOM = 1, }

DampMode#

enum DampMode { DAMP_MODE_COMBINE = 0, DAMP_MODE_REPLACE = 1, }

CCDMode#

enum CCDMode { CCD_MODE_DISABLED = 0, CCD_MODE_CAST_RAY = 1, CCD_MODE_CAST_SHAPE = 2, }

Operators #

Signals #

signal body_entered(body: Node)#

Emitted when a collision with another PhysicsBody2D or TileMap occurs. Requires contact_monitor to be set to true and max_contacts_reported to be set high enough to detect all the collisions. TileMaps are detected if the TileSet has Collision Shape2Ds.

body the Node, if it exists in the tree, of the other PhysicsBody2D or TileMap.

signal body_exited(body: Node)#

Emitted when the collision with another PhysicsBody2D or TileMap ends. Requires contact_monitor to be set to true and max_contacts_reported to be set high enough to detect all the collisions. TileMaps are detected if the TileSet has Collision Shape2Ds.

body the Node, if it exists in the tree, of the other PhysicsBody2D or TileMap.

signal body_shape_entered(local_shape_index: int)#

Emitted when one of this RigidBody2D's Shape2Ds collides with another PhysicsBody2D or TileMap's Shape2Ds. Requires contact_monitor to be set to true and max_contacts_reported to be set high enough to detect all the collisions. TileMaps are detected if the TileSet has Collision Shape2Ds.

body_rid the RID of the other PhysicsBody2D or TileSet's CollisionObject2D used by the PhysicsServer2D.

body the Node, if it exists in the tree, of the other PhysicsBody2D or TileMap.

body_shape_index the index of the Shape2D of the other PhysicsBody2D or TileMap used by the PhysicsServer2D. Get the CollisionShape2D node with body.shape_owner_get_owner(body.shape_find_owner(body_shape_index)).

local_shape_index the index of the Shape2D of this RigidBody2D used by the PhysicsServer2D. Get the CollisionShape2D node with self.shape_owner_get_owner(self.shape_find_owner(local_shape_index)).

signal body_shape_exited(local_shape_index: int)#

Emitted when the collision between one of this RigidBody2D's Shape2Ds and another PhysicsBody2D or TileMap's Shape2Ds ends. Requires contact_monitor to be set to true and max_contacts_reported to be set high enough to detect all the collisions. TileMaps are detected if the TileSet has Collision Shape2Ds.

body_rid the RID of the other PhysicsBody2D or TileSet's CollisionObject2D used by the PhysicsServer2D.

body the Node, if it exists in the tree, of the other PhysicsBody2D or TileMap.

body_shape_index the index of the Shape2D of the other PhysicsBody2D or TileMap used by the PhysicsServer2D. Get the CollisionShape2D node with body.shape_owner_get_owner(body.shape_find_owner(body_shape_index)).

local_shape_index the index of the Shape2D of this RigidBody2D used by the PhysicsServer2D. Get the CollisionShape2D node with self.shape_owner_get_owner(self.shape_find_owner(local_shape_index)).

signal 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.

Theme Items #

Tutorials #