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Class: RevoluteJoint

A revolute joint constrains two bodies to share a common point while they are free to rotate about the point. The relative rotation about the shared point is the joint angle. You can limit the relative rotation with a joint limit that specifies a lower and upper angle. You can use a motor to drive the relative rotation about the shared point. A maximum motor torque is provided so that infinite forces are not generated.

Extends

Constructors

Constructor

new RevoluteJoint(def): RevoluteJoint

Parameters

def

RevoluteJointDef

Returns

RevoluteJoint

Overrides

Joint.constructor

Constructor

new RevoluteJoint(def, bodyA, bodyB, anchor?): RevoluteJoint

Parameters

def

RevoluteJointOpt

bodyA

Body

bodyB

Body

anchor?

Vec2Value

Returns

RevoluteJoint

Overrides

Joint.constructor

Properties

style

style: Style = {}

Styling for dev-tools.

Inherited from

Joint.style


TYPE

static TYPE: "revolute-joint"

Methods

enableLimit()

enableLimit(flag): void

Enable/disable the joint limit.

Parameters

flag

boolean

Returns

void


enableMotor()

enableMotor(flag): void

Enable/disable the joint motor.

Parameters

flag

boolean

Returns

void


getAnchorA()

getAnchorA(): Vec2

Get the anchor point on bodyA in world coordinates.

Returns

Vec2

Overrides

Joint.getAnchorA


getAnchorB()

getAnchorB(): Vec2

Get the anchor point on bodyB in world coordinates.

Returns

Vec2

Overrides

Joint.getAnchorB


getBodyA()

getBodyA(): Body

Get the first body attached to this joint.

Returns

Body

Inherited from

Joint.getBodyA


getBodyB()

getBodyB(): Body

Get the second body attached to this joint.

Returns

Body

Inherited from

Joint.getBodyB


getCollideConnected()

getCollideConnected(): boolean

Get collide connected. Note: modifying the collide connect flag won't work correctly because the flag is only checked when fixture AABBs begin to overlap.

Returns

boolean

Inherited from

Joint.getCollideConnected


getJointAngle()

getJointAngle(): number

Get the current joint angle in radians.

Returns

number


getJointSpeed()

getJointSpeed(): number

Get the current joint angle speed in radians per second.

Returns

number


getLocalAnchorA()

getLocalAnchorA(): Vec2

The local anchor point relative to bodyA's origin.

Returns

Vec2


getLocalAnchorB()

getLocalAnchorB(): Vec2

The local anchor point relative to bodyB's origin.

Returns

Vec2


getLowerLimit()

getLowerLimit(): number

Get the lower joint limit in radians.

Returns

number


getMaxMotorTorque()

getMaxMotorTorque(): number

Returns

number


getMotorSpeed()

getMotorSpeed(): number

Get the motor speed in radians per second.

Returns

number


getMotorTorque()

getMotorTorque(inv_dt): number

Get the current motor torque given the inverse time step. Unit is N*m.

Parameters

inv_dt

number

Returns

number


getNext()

getNext(): Joint

Get the next joint the world joint list.

Returns

Joint

Inherited from

Joint.getNext


getReactionForce()

getReactionForce(inv_dt): Vec2

Get the reaction force given the inverse time step. Unit is N.

Parameters

inv_dt

number

Returns

Vec2

Overrides

Joint.getReactionForce


getReactionTorque()

getReactionTorque(inv_dt): number

Get the reaction torque due to the joint limit given the inverse time step. Unit is N*m.

Parameters

inv_dt

number

Returns

number

Overrides

Joint.getReactionTorque


getReferenceAngle()

getReferenceAngle(): number

Get the reference angle.

Returns

number


getType()

getType(): string

Get the type of the concrete joint.

Returns

string

Inherited from

Joint.getType


getUpperLimit()

getUpperLimit(): number

Get the upper joint limit in radians.

Returns

number


getUserData()

getUserData(): unknown

Returns

unknown

Inherited from

Joint.getUserData


initVelocityConstraints()

initVelocityConstraints(step): void

Parameters

step

TimeStep

Returns

void

Overrides

Joint.initVelocityConstraints


isActive()

isActive(): boolean

Short-cut function to determine if either body is inactive.

Returns

boolean

Inherited from

Joint.isActive


isLimitEnabled()

isLimitEnabled(): boolean

Is the joint limit enabled?

Returns

boolean


isMotorEnabled()

isMotorEnabled(): boolean

Is the joint motor enabled?

Returns

boolean


setLimits()

setLimits(lower, upper): void

Set the joint limits in radians.

Parameters

lower

number

upper

number

Returns

void


setMaxMotorTorque()

setMaxMotorTorque(torque): void

Set the maximum motor torque, usually in N-m.

Parameters

torque

number

Returns

void


setMotorSpeed()

setMotorSpeed(speed): void

Set the motor speed in radians per second.

Parameters

speed

number

Returns

void


setUserData()

setUserData(data): void

Parameters

data

unknown

Returns

void

Inherited from

Joint.setUserData


shiftOrigin()

shiftOrigin(newOrigin): void

Shift the origin for any points stored in world coordinates.

Parameters

newOrigin

Vec2Value

Returns

void

Inherited from

Joint.shiftOrigin


solvePositionConstraints()

solvePositionConstraints(step): boolean

This returns true if the position errors are within tolerance.

Parameters

step

TimeStep

Returns

boolean

Overrides

Joint.solvePositionConstraints


solveVelocityConstraints()

solveVelocityConstraints(step): void

Parameters

step

TimeStep

Returns

void

Overrides

Joint.solveVelocityConstraints