Object
- AbstractJoint<T>
- - AbstractPairedBodyJoint<T>
  - - WheelJoint<T>

Type Parameters:

T - the PhysicsBody type

All Implemented Interfaces:

DataContainer, AngularMotorJoint, Joint<T>, LinearLimitsJoint, LinearSpringJoint, PairedBodyJoint<T>, Shiftable, Ownable
```
public class WheelJoint<T extends PhysicsBody>
extends AbstractPairedBodyJoint<T>
implements LinearLimitsJoint, LinearSpringJoint, AngularMotorJoint, PairedBodyJoint<T>, Joint<T>, Shiftable, DataContainer, Ownable
```
Implementation of a wheel joint.
A wheel joint is used to simulate a vehicle's wheel and suspension. The wheel is allowed to rotate freely about the given anchor point. The suspension is allowed to translate freely along the given axis. The whole system can translate and rotate freely.
The given axis fixed to the first body (frame) given. So as the first body rotates, the axis will rotate with it. The given anchor point represents the center of rotation of the second body (wheel), typically the wheel's world space center of mass.
By default the frequency and damping ratio are set to 8.0 and 0.0 respectively. Unlike other joints, the spring-damper for this joint is enabled by default. You can enable/disable the various spring-damper features using setSpringEnabled(boolean), setSpringDamperEnabled(boolean), setMaximumSpringForceEnabled(boolean) methods. As with all spring -damper enabled joints, the spring must be enabled for the damper to be applied. Also note that when the damper is disabled, the spring still experiences "damping" aka energy loss - this is a side effect of the solver and intended behavior.
This joint has an added spring feature called the rest offset. Similar to the rest distance in the distance joint, but only applied when the spring is enabled. When you build the joint, the default distance between the two bodies is their initial distance. You can use the setSpringRestOffset(double) to raise or lower the distance between the bodies when the spring is active.
This joint also supports a motor. The motor is an angular motor about the anchor point. The motor speed can be positive or negative to indicate a clockwise or counter-clockwise rotation. The maximum motor torque must be greater than zero for the motor to apply any motion. The motor must be enabled using setMotorEnabled(boolean).
The joint also supports upper and lower limits. The limits represent the maximum displacement from the anchor point along the given axis. This means that the limits are typically negative for the lower limit and positive for the upper limit. The limits are solved relative to the given axis's direction. The limits can be enabled separately using setLowerLimitEnabled(boolean) and setUpperLimitEnabled(boolean). This also means that the limits are relative to the initial starting position of the bodies.
NOTE: In versions of dyn4j before 5.0.0, the body arguments in the constructor were reversed, you would specify the wheel first, then frame. It was changed to accept the frame first, then the wheel to make things more natural.

Since:

3.0.0

Version:

5.0.0

Author:

William Bittle

See Also:

Documentation

Field Summary

Fields
Modifier and Type	Field	Description
`protected Vector2`	`localAnchor1`	The local anchor point on the first `PhysicsBody`
`protected Vector2`	`localAnchor2`	The local anchor point on the second `PhysicsBody`
`protected double`	`lowerLimit`	the lower limit in meters
`protected boolean`	`lowerLimitEnabled`	True if the lower limit is enabled
`protected boolean`	`motorEnabled`	Whether the motor is enabled or not
`protected double`	`motorMaximumTorque`	The maximum torque the motor can apply in newton-meters
`protected boolean`	`motorMaximumTorqueEnabled`	True if the motor maximum torque is enabled
`protected double`	`motorSpeed`	The target velocity in radians / second
`protected boolean`	`springDamperEnabled`	True if the spring-damper is enabled
`protected double`	`springDampingRatio`	The damping ratio
`protected boolean`	`springEnabled`	True if the spring is enabled
`protected double`	`springFrequency`	The oscillation frequency in hz
`protected double`	`springMaximumForce`	The maximum force the spring will apply
`protected boolean`	`springMaximumForceEnabled`	True if the spring maximum force is enabled
`protected int`	`springMode`	The spring mode (frequency or stiffness)
`protected double`	`springRestOffset`	The rest offset of the spring
`protected double`	`springStiffness`	The stiffness of the spring
`protected double`	`upperLimit`	the upper limit in meters
`protected boolean`	`upperLimitEnabled`	True if the upper limit is enabled
`protected Vector2`	`xAxis`	The local space x axis representing the allowed linear motion
`protected Vector2`	`yAxis`	The local space y axis representing the constrained linear motion

Fields inherited from class AbstractPairedBodyJoint
body1, body2

Fields inherited from class AbstractJoint
bodies, collisionAllowed, owner, userData

Fields inherited from interface Joint
SPRING_MODE_FREQUENCY, SPRING_MODE_STIFFNESS

Constructor Summary

Constructors
Constructor Description

WheelJoint(T frame, T wheel, Vector2 anchor, Vector2 axis)
Minimal constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`Vector2`	`getAnchor1()`	The anchor point in world coordinates for the frame (body1).
`Vector2`	`getAnchor2()`	The anchor point in world coordinates for the wheel (body2).
`double`	`getAngularSpeed()`	Returns the current angular speed between the two joined bodies.
`double`	`getAngularTranslation()`	Returns the current angular translation between the joined bodies.
`Vector2`	`getAxis()`	Returns the axis in world coordinates for the frame (body1).
`double`	`getLinearSpeed()`	Returns the linear speed along the axis between the two joined bodies
`double`	`getLinearTranslation()`	Returns the current linear translation along the joint axis.
`double`	`getLowerLimit()`	Returns the lower limit in meters.
`double`	`getMaximumMotorTorque()`	Returns the maximum torque the motor can apply to the joint to achieve the target speed.
`double`	`getMaximumSpringForce()`	Returns the maximum spring force that will be applied.
`double`	`getMotorSpeed()`	Returns the target motor speed in radians / second.
`double`	`getMotorTorque(double invdt)`	Returns the applied motor torque.
`Vector2`	`getReactionForce(double invdt)`	Returns the force applied to the `PhysicsBody`s in order to satisfy the constraint in newtons.
`double`	`getReactionTorque(double invdt)`	Returns the torque applied to the `PhysicsBody`s in order to satisfy the constraint in newton-meters.
`double`	`getSpringDampingRatio()`	Returns the damping ratio for the spring's damper.
`double`	`getSpringForce(double invdt)`	Returns the force in netwons applied by the spring in the last timestep.
`double`	`getSpringFrequency()`	Returns the spring frequency.
`int`	`getSpringMode()`	Returns the current spring mode.
`double`	`getSpringRestOffset()`	Returns the spring's rest offset.
`double`	`getSpringStiffness()`	Returns the spring stiffness.
`double`	`getUpperLimit()`	Returns the upper limit in meters.
`void`	`initializeConstraints(TimeStep step, Settings settings)`	Performs any initialization of the velocity and position constraints.
`boolean`	`isLowerLimitEnabled()`	Returns true if the lower limit is enabled.
`boolean`	`isMaximumMotorTorqueEnabled()`	Returns true if the maximum motor torque is enabled.
`boolean`	`isMaximumSpringForceEnabled()`	Returns true if the spring force is limited to the maximum.
`boolean`	`isMotorEnabled()`	Returns true if the motor is enabled.
`boolean`	`isSpringDamperEnabled()`	Returns true if the damper is enabled for the spring.
`boolean`	`isSpringEnabled()`	Returns true if the spring is enabled.
`boolean`	`isUpperLimitEnabled()`	Returns true if the upper limit is enabled.
`void`	`setLimits(double limit)`	Sets both the lower and upper limits to the given limit.
`void`	`setLimits(double lowerLimit, double upperLimit)`	Sets both the lower and upper limits.
`void`	`setLimitsEnabled(boolean flag)`	Enables or disables both the lower and upper limits.
`void`	`setLimitsEnabled(double limit)`	Sets both the lower and upper limits to the given limit and enables both.
`void`	`setLimitsEnabled(double lowerLimit, double upperLimit)`	Sets both the lower and upper limits and enables both.
`void`	`setLowerLimit(double lowerLimit)`	Sets the lower limit in meters.
`void`	`setLowerLimitEnabled(boolean flag)`	Sets whether the lower limit is enabled.
`void`	`setMaximumMotorTorque(double maximumMotorTorque)`	Sets the maximum torque the motor can apply to the joint to achieve the target speed.
`void`	`setMaximumMotorTorqueEnabled(boolean enabled)`	Sets whether the maximum motor torque is enabled.
`void`	`setMaximumSpringForce(double maximum)`	Sets the maximum force the spring can apply.
`void`	`setMaximumSpringForceEnabled(boolean enabled)`	Sets whether the spring force is limited to the maximum.
`void`	`setMotorEnabled(boolean motorEnabled)`	Enables or disables the motor.
`void`	`setMotorSpeed(double motorSpeed)`	Sets the target motor speed.
`void`	`setSpringDamperEnabled(boolean enabled)`	Sets whether the spring's damper is enabled or not.
`void`	`setSpringDampingRatio(double dampingRatio)`	Sets the damping ratio.
`void`	`setSpringEnabled(boolean enabled)`	Sets whether the spring is enabled or not.
`void`	`setSpringFrequency(double frequency)`	Sets the spring frequency.
`void`	`setSpringRestOffset(double offset)`	Set's the spring rest offset.
`void`	`setSpringStiffness(double stiffness)`	Sets the spring stiffness.
`void`	`setUpperLimit(double upperLimit)`	Sets the upper limit in meters.
`void`	`setUpperLimitEnabled(boolean flag)`	Sets whether the upper limit is enabled.
`void`	`shift(Vector2 shift)`	Translates the object to match the given coordinate shift.
`boolean`	`solvePositionConstraints(TimeStep step, Settings settings)`	Solves the position constraints.
`void`	`solveVelocityConstraints(TimeStep step, Settings settings)`	Solves the velocity constraints.
`String`	`toString()`
`protected void`	`updateSpringCoefficients()`	Computes the spring coefficients from the current state of the joint.

Methods inherited from class AbstractPairedBodyJoint
getBody, getBody1, getBody2, getBodyCount, getOtherBody, getReducedInertia, getReducedMass, isEnabled, isMember, setCollisionAllowed

Methods inherited from class AbstractJoint
getBodies, getBodyIterator, getConstraintImpulseMixing, getErrorReductionParameter, getFrequency, getNaturalFrequency, getNaturalFrequency, getOwner, getSpringDampingCoefficient, getSpringStiffness, getUserData, isCollisionAllowed, setOwner, setUserData

Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface DataContainer
getUserData, setUserData

Methods inherited from interface Joint
getBodies, getBody, getBodyCount, getBodyIterator, isCollisionAllowed, isEnabled, isMember, setCollisionAllowed

Methods inherited from interface Ownable
getOwner, setOwner

Methods inherited from interface PairedBodyJoint
getBody1, getBody2, getOtherBody

- Field Detail
  - localAnchor1
```
protected final Vector2 localAnchor1
```
    The local anchor point on the first PhysicsBody
  - localAnchor2
```
protected final Vector2 localAnchor2
```
    The local anchor point on the second PhysicsBody
  - xAxis
```
protected final Vector2 xAxis
```
    The local space x axis representing the allowed linear motion
  - yAxis
```
protected final Vector2 yAxis
```
    The local space y axis representing the constrained linear motion
  - upperLimitEnabled
```
protected boolean upperLimitEnabled
```
    True if the upper limit is enabled
  - lowerLimitEnabled
```
protected boolean lowerLimitEnabled
```
    True if the lower limit is enabled
  - upperLimit
```
protected double upperLimit
```
    the upper limit in meters
  - lowerLimit
```
protected double lowerLimit
```
    the lower limit in meters
  - motorEnabled
```
protected boolean motorEnabled
```
    Whether the motor is enabled or not
  - motorSpeed
```
protected double motorSpeed
```
    The target velocity in radians / second
  - motorMaximumTorqueEnabled
```
protected boolean motorMaximumTorqueEnabled
```
    True if the motor maximum torque is enabled
  - motorMaximumTorque
```
protected double motorMaximumTorque
```
    The maximum torque the motor can apply in newton-meters
  - springEnabled
```
protected boolean springEnabled
```
    True if the spring is enabled
  - springDamperEnabled
```
protected boolean springDamperEnabled
```
    True if the spring-damper is enabled
  - springMode
```
protected int springMode
```
    The spring mode (frequency or stiffness)
  - springFrequency
```
protected double springFrequency
```
    The oscillation frequency in hz
  - springStiffness
```
protected double springStiffness
```
    The stiffness of the spring
  - springDampingRatio
```
protected double springDampingRatio
```
    The damping ratio
  - springMaximumForceEnabled
```
protected boolean springMaximumForceEnabled
```
    True if the spring maximum force is enabled
  - springMaximumForce
```
protected double springMaximumForce
```
    The maximum force the spring will apply
  - springRestOffset
```
protected double springRestOffset
```
    The rest offset of the spring
- Constructor Detail
  - WheelJoint
```
public WheelJoint(T frame,
                  T wheel,
                  Vector2 anchor,
                  Vector2 axis)
```
    Minimal constructor.
    
    Parameters:
    
    frame - the frame PhysicsBody
    
    wheel - the wheel PhysicsBody
    
    anchor - the anchor point in world coordinates
    
    axis - the axis of allowed motion
    
    Throws:
    
    NullPointerException - if body1, body2, anchor, or axis is null
    
    IllegalArgumentException - if body1 == body2
- Method Detail
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class AbstractJoint<T extends PhysicsBody>
  - initializeConstraints
```
public void initializeConstraints(TimeStep step,
                                  Settings settings)
```
    Description copied from interface: Joint
    
    Performs any initialization of the velocity and position constraints.
    
    Specified by:
    
    initializeConstraints in interface Joint<T extends PhysicsBody>
    
    Parameters:
    
    step - the time step information
    
    settings - the current world settings
  - solveVelocityConstraints
```
public void solveVelocityConstraints(TimeStep step,
                                     Settings settings)
```
    Description copied from interface: Joint
    
    Solves the velocity constraints.
    
    Specified by:
    
    solveVelocityConstraints in interface Joint<T extends PhysicsBody>
    
    Parameters:
    
    step - the time step information
    
    settings - the current world settings
  - solvePositionConstraints
```
public boolean solvePositionConstraints(TimeStep step,
                                        Settings settings)
```
    Description copied from interface: Joint
    
    Solves the position constraints.
    
    Specified by:
    
    solvePositionConstraints in interface Joint<T extends PhysicsBody>
    
    Parameters:
    
    step - the time step information
    
    settings - the current world settings
    
    Returns:
    
    boolean true if the position constraints were solved
  - updateSpringCoefficients
```
protected void updateSpringCoefficients()
```
    Computes the spring coefficients from the current state of the joint.
    This method is intended to set the springStiffness OR springFrequency and damping for use during constraint solving.
  - getAnchor1
```
public Vector2 getAnchor1()
```
    The anchor point in world coordinates for the frame (body1).
    
    Returns:
    
    Vector2
  - getAnchor2
```
public Vector2 getAnchor2()
```
    The anchor point in world coordinates for the wheel (body2).
    
    Returns:
    
    Vector2
  - getReactionForce
```
public Vector2 getReactionForce(double invdt)
```
    Description copied from interface: Joint
    
    Returns the force applied to the PhysicsBodys in order to satisfy the constraint in newtons.
    
    Specified by:
    
    getReactionForce in interface Joint<T extends PhysicsBody>
    
    Parameters:
    
    invdt - the inverse delta time
    
    Returns:
    
    Vector2
  - getReactionTorque
```
public double getReactionTorque(double invdt)
```
    Description copied from interface: Joint
    
    Returns the torque applied to the PhysicsBodys in order to satisfy the constraint in newton-meters.
    
    Specified by:
    
    getReactionTorque in interface Joint<T extends PhysicsBody>
    
    Parameters:
    
    invdt - the inverse delta time
    
    Returns:
    
    double
  - shift
```
public void shift(Vector2 shift)
```
    Description copied from interface: Shiftable
    
    Translates the object to match the given coordinate shift.
    
    Specified by:
    
    shift in interface Shiftable
    
    Parameters:
    
    shift - the amount to shift along the x and y axes
  - getLinearSpeed
```
public double getLinearSpeed()
```
    Returns the linear speed along the axis between the two joined bodies
    
    Returns:
    
    double
    
    Since:
    
    3.2.1
  - getAngularSpeed
```
public double getAngularSpeed()
```
    Returns the current angular speed between the two joined bodies.
    
    Returns:
    
    double
    
    Since:
    
    3.2.1
  - getLinearTranslation
```
public double getLinearTranslation()
```
    Returns the current linear translation along the joint axis.
    
    Returns:
    
    double
    
    Since:
    
    3.2.1
  - getAngularTranslation
```
public double getAngularTranslation()
```
    Returns the current angular translation between the joined bodies.
    
    Returns:
    
    double
    
    Since:
    
    3.2.1
  - getAxis
```
public Vector2 getAxis()
```
    Returns the axis in world coordinates for the frame (body1).
    
    Returns:
    
    Vector2
  - setSpringRestOffset
```
public void setSpringRestOffset(double offset)
```
    Set's the spring rest offset.
    This can be any value and is used to offset the spring's rest distance. This is only applicable when the spring is enabled.
    
    Parameters:
    
    offset - the offset
    
    Since:
    
    5.0.0
  - getSpringRestOffset
```
public double getSpringRestOffset()
```
    Returns the spring's rest offset.
    
    Returns:
    
    double
    
    Since:
    
    5.0.0
  - isMotorEnabled
```
public boolean isMotorEnabled()
```
    Description copied from interface: AngularMotorJoint
    
    Returns true if the motor is enabled.
    
    Specified by:
    
    isMotorEnabled in interface AngularMotorJoint
    
    Returns:
    
    boolean
  - setMotorEnabled
```
public void setMotorEnabled(boolean motorEnabled)
```
    Description copied from interface: AngularMotorJoint
    
    Enables or disables the motor.
    
    Specified by:
    
    setMotorEnabled in interface AngularMotorJoint
    
    Parameters:
    
    motorEnabled - true if the motor should be enabled
  - getMotorSpeed
```
public double getMotorSpeed()
```
    Description copied from interface: AngularMotorJoint
    
    Returns the target motor speed in radians / second.
    
    Specified by:
    
    getMotorSpeed in interface AngularMotorJoint
    
    Returns:
    
    double
  - setMotorSpeed
```
public void setMotorSpeed(double motorSpeed)
```
    Description copied from interface: AngularMotorJoint
    
    Sets the target motor speed.
    
    Specified by:
    
    setMotorSpeed in interface AngularMotorJoint
    
    Parameters:
    
    motorSpeed - the target motor speed in radians / second
    
    See Also:
    
    AngularMotorJoint.setMaximumMotorTorque(double)
  - isMaximumMotorTorqueEnabled
```
public boolean isMaximumMotorTorqueEnabled()
```
    Description copied from interface: AngularMotorJoint
    
    Returns true if the maximum motor torque is enabled.
    
    Specified by:
    
    isMaximumMotorTorqueEnabled in interface AngularMotorJoint
    
    Returns:
    
    boolean
  - setMaximumMotorTorqueEnabled
```
public void setMaximumMotorTorqueEnabled(boolean enabled)
```
    Description copied from interface: AngularMotorJoint
    
    Sets whether the maximum motor torque is enabled.
    
    Specified by:
    
    setMaximumMotorTorqueEnabled in interface AngularMotorJoint
    
    Parameters:
    
    enabled - true if the maximum motor torque should be enabled
  - getMaximumMotorTorque
```
public double getMaximumMotorTorque()
```
    Description copied from interface: AngularMotorJoint
    
    Returns the maximum torque the motor can apply to the joint to achieve the target speed.
    
    Specified by:
    
    getMaximumMotorTorque in interface AngularMotorJoint
    
    Returns:
    
    double
  - setMaximumMotorTorque
```
public void setMaximumMotorTorque(double maximumMotorTorque)
```
    Description copied from interface: AngularMotorJoint
    
    Sets the maximum torque the motor can apply to the joint to achieve the target speed.
    
    Specified by:
    
    setMaximumMotorTorque in interface AngularMotorJoint
    
    Parameters:
    
    maximumMotorTorque - the maximum torque in newtons-meters; in the range (0, ∞]
    
    See Also:
    
    AngularMotorJoint.setMotorSpeed(double)
  - getMotorTorque
```
public double getMotorTorque(double invdt)
```
    Description copied from interface: AngularMotorJoint
    
    Returns the applied motor torque.
    
    Specified by:
    
    getMotorTorque in interface AngularMotorJoint
    
    Parameters:
    
    invdt - the inverse delta time from the time step
    
    Returns:
    
    double
  - getSpringDampingRatio
```
public double getSpringDampingRatio()
```
    Description copied from interface: LinearSpringJoint
    
    Returns the damping ratio for the spring's damper.
    
    Specified by:
    
    getSpringDampingRatio in interface LinearSpringJoint
    
    Returns:
    
    double
  - setSpringDampingRatio
```
public void setSpringDampingRatio(double dampingRatio)
```
    Description copied from interface: LinearSpringJoint
    
    Sets the damping ratio.
    Larger values reduce the oscillation of the spring.
    
    Specified by:
    
    setSpringDampingRatio in interface LinearSpringJoint
    
    Parameters:
    
    dampingRatio - the damping ratio; in the range (0, 1]
  - getSpringFrequency
```
public double getSpringFrequency()
```
    Description copied from interface: LinearSpringJoint
    
    Returns the spring frequency.
    
    Specified by:
    
    getSpringFrequency in interface LinearSpringJoint
    
    Returns:
    
    double
  - getSpringStiffness
```
public double getSpringStiffness()
```
    Description copied from interface: LinearSpringJoint
    
    Returns the spring stiffness.
    
    Specified by:
    
    getSpringStiffness in interface LinearSpringJoint
    
    Returns:
    
    double
  - setSpringFrequency
```
public void setSpringFrequency(double frequency)
```
    Description copied from interface: LinearSpringJoint
    
    Sets the spring frequency.
    Larger values increase the stiffness of the spring.
    Calling this method puts the spring into fixed frequency mode. In this mode, the spring stiffness is computed based on the frequency.
    
    Specified by:
    
    setSpringFrequency in interface LinearSpringJoint
    
    Parameters:
    
    frequency - the spring frequency in hz; must be greater than zero
  - setSpringStiffness
```
public void setSpringStiffness(double stiffness)
```
    Description copied from interface: LinearSpringJoint
    
    Sets the spring stiffness.
    Larger values increase the stiffness of the spring.
    Calling this method puts the spring into fixed stiffness mode. In this mode, the spring frequency is computed based on the stiffness.
    
    Specified by:
    
    setSpringStiffness in interface LinearSpringJoint
    
    Parameters:
    
    stiffness - the spring stiffness (k); must be greater than zero
  - getMaximumSpringForce
```
public double getMaximumSpringForce()
```
    Description copied from interface: LinearSpringJoint
    
    Returns the maximum spring force that will be applied.
    
    Specified by:
    
    getMaximumSpringForce in interface LinearSpringJoint
    
    Returns:
    
    double
  - setMaximumSpringForce
```
public void setMaximumSpringForce(double maximum)
```
    Description copied from interface: LinearSpringJoint
    
    Sets the maximum force the spring can apply.
    
    Specified by:
    
    setMaximumSpringForce in interface LinearSpringJoint
    
    Parameters:
    
    maximum - the maximum force
  - isMaximumSpringForceEnabled
```
public boolean isMaximumSpringForceEnabled()
```
    Description copied from interface: LinearSpringJoint
    
    Returns true if the spring force is limited to the maximum.
    
    Specified by:
    
    isMaximumSpringForceEnabled in interface LinearSpringJoint
    
    Returns:
    
    boolean
  - setMaximumSpringForceEnabled
```
public void setMaximumSpringForceEnabled(boolean enabled)
```
    Description copied from interface: LinearSpringJoint
    
    Sets whether the spring force is limited to the maximum.
    
    Specified by:
    
    setMaximumSpringForceEnabled in interface LinearSpringJoint
    
    Parameters:
    
    enabled - true if the spring force should be limited
  - isSpringEnabled
```
public boolean isSpringEnabled()
```
    Description copied from interface: LinearSpringJoint
    
    Returns true if the spring is enabled.
    
    Specified by:
    
    isSpringEnabled in interface LinearSpringJoint
    
    Returns:
    
    boolean
  - setSpringEnabled
```
public void setSpringEnabled(boolean enabled)
```
    Description copied from interface: LinearSpringJoint
    
    Sets whether the spring is enabled or not.
    
    Specified by:
    
    setSpringEnabled in interface LinearSpringJoint
    
    Parameters:
    
    enabled - true if the spring should be enabled
  - isSpringDamperEnabled
```
public boolean isSpringDamperEnabled()
```
    Description copied from interface: LinearSpringJoint
    
    Returns true if the damper is enabled for the spring.
    NOTE: for the damper to have any effect, the spring must be enabled.
    
    Specified by:
    
    isSpringDamperEnabled in interface LinearSpringJoint
    
    Returns:
    
    boolean
    
    See Also:
    
    LinearSpringJoint.isSpringEnabled()
  - setSpringDamperEnabled
```
public void setSpringDamperEnabled(boolean enabled)
```
    Description copied from interface: LinearSpringJoint
    
    Sets whether the spring's damper is enabled or not.
    NOTE: for the damper to have any effect, the spring must be enabled.
    
    Specified by:
    
    setSpringDamperEnabled in interface LinearSpringJoint
    
    Parameters:
    
    enabled - true if the damper should be enabled
    
    See Also:
    
    LinearSpringJoint.setSpringEnabled(boolean)
  - getSpringForce
```
public double getSpringForce(double invdt)
```
    Description copied from interface: LinearSpringJoint
    
    Returns the force in netwons applied by the spring in the last timestep.
    
    Specified by:
    
    getSpringForce in interface LinearSpringJoint
    
    Parameters:
    
    invdt - the inverse delta time
    
    Returns:
    
    double
  - getSpringMode
```
public int getSpringMode()
```
    Description copied from interface: LinearSpringJoint
    
    Returns the current spring mode.
    NOTE: The spring mode is set automatically when you call either LinearSpringJoint.setSpringFrequency(double) or LinearSpringJoint.setSpringStiffness(double). Use this method to store the spring mode when saving the simulation state and use the value to call either LinearSpringJoint.setSpringFrequency(double) or LinearSpringJoint.setSpringStiffness(double).
    
    Specified by:
    
    getSpringMode in interface LinearSpringJoint
    
    Returns:
    
    int
    
    See Also:
    
    Joint.SPRING_MODE_FREQUENCY, Joint.SPRING_MODE_STIFFNESS
  - getUpperLimit
```
public double getUpperLimit()
```
    Description copied from interface: LinearLimitsJoint
    
    Returns the upper limit in meters.
    
    Specified by:
    
    getUpperLimit in interface LinearLimitsJoint
    
    Returns:
    
    double
  - setUpperLimit
```
public void setUpperLimit(double upperLimit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets the upper limit in meters.
    
    Specified by:
    
    setUpperLimit in interface LinearLimitsJoint
    
    Parameters:
    
    upperLimit - the upper limit in meters
  - setUpperLimitEnabled
```
public void setUpperLimitEnabled(boolean flag)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets whether the upper limit is enabled.
    
    Specified by:
    
    setUpperLimitEnabled in interface LinearLimitsJoint
    
    Parameters:
    
    flag - true if the upper limit should be enabled
  - isUpperLimitEnabled
```
public boolean isUpperLimitEnabled()
```
    Description copied from interface: LinearLimitsJoint
    
    Returns true if the upper limit is enabled.
    
    Specified by:
    
    isUpperLimitEnabled in interface LinearLimitsJoint
    
    Returns:
    
    boolean true if the upper limit is enabled
  - getLowerLimit
```
public double getLowerLimit()
```
    Description copied from interface: LinearLimitsJoint
    
    Returns the lower limit in meters.
    
    Specified by:
    
    getLowerLimit in interface LinearLimitsJoint
    
    Returns:
    
    double
  - setLowerLimit
```
public void setLowerLimit(double lowerLimit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets the lower limit in meters.
    
    Specified by:
    
    setLowerLimit in interface LinearLimitsJoint
    
    Parameters:
    
    lowerLimit - the lower limit in meters
  - setLowerLimitEnabled
```
public void setLowerLimitEnabled(boolean flag)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets whether the lower limit is enabled.
    
    Specified by:
    
    setLowerLimitEnabled in interface LinearLimitsJoint
    
    Parameters:
    
    flag - true if the lower limit should be enabled
  - isLowerLimitEnabled
```
public boolean isLowerLimitEnabled()
```
    Description copied from interface: LinearLimitsJoint
    
    Returns true if the lower limit is enabled.
    
    Specified by:
    
    isLowerLimitEnabled in interface LinearLimitsJoint
    
    Returns:
    
    boolean true if the lower limit is enabled
  - setLimits
```
public void setLimits(double lowerLimit,
                      double upperLimit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets both the lower and upper limits.
    
    Specified by:
    
    setLimits in interface LinearLimitsJoint
    
    Parameters:
    
    lowerLimit - the lower limit in meters
    
    upperLimit - the upper limit in meters
  - setLimitsEnabled
```
public void setLimitsEnabled(double lowerLimit,
                             double upperLimit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets both the lower and upper limits and enables both.
    
    Specified by:
    
    setLimitsEnabled in interface LinearLimitsJoint
    
    Parameters:
    
    lowerLimit - the lower limit in meters
    
    upperLimit - the upper limit in meters
  - setLimitsEnabled
```
public void setLimitsEnabled(boolean flag)
```
    Description copied from interface: LinearLimitsJoint
    
    Enables or disables both the lower and upper limits.
    
    Specified by:
    
    setLimitsEnabled in interface LinearLimitsJoint
    
    Parameters:
    
    flag - true if both limits should be enabled
  - setLimits
```
public void setLimits(double limit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets both the lower and upper limits to the given limit.
    
    Specified by:
    
    setLimits in interface LinearLimitsJoint
    
    Parameters:
    
    limit - the desired limit in meters
  - setLimitsEnabled
```
public void setLimitsEnabled(double limit)
```
    Description copied from interface: LinearLimitsJoint
    
    Sets both the lower and upper limits to the given limit and enables both.
    
    Specified by:
    
    setLimitsEnabled in interface LinearLimitsJoint
    
    Parameters:
    
    limit - the desired limit in meters

Class WheelJoint<T extends PhysicsBody>

Field Summary

Fields inherited from class AbstractPairedBodyJoint

Fields inherited from class AbstractJoint

Fields inherited from interface Joint

Constructor Summary

Method Summary

Methods inherited from class AbstractPairedBodyJoint

Methods inherited from class AbstractJoint

Methods inherited from class Object

Methods inherited from interface DataContainer

Methods inherited from interface Joint

Methods inherited from interface Ownable

Methods inherited from interface PairedBodyJoint

Field Detail

localAnchor1

localAnchor2

xAxis

yAxis

upperLimitEnabled

lowerLimitEnabled

upperLimit

lowerLimit

motorEnabled

motorSpeed

motorMaximumTorqueEnabled

motorMaximumTorque

springEnabled

springDamperEnabled

springMode

springFrequency

springStiffness

springDampingRatio

springMaximumForceEnabled

springMaximumForce

springRestOffset

Constructor Detail

WheelJoint

Method Detail

toString

initializeConstraints

solveVelocityConstraints

solvePositionConstraints

updateSpringCoefficients

getAnchor1

getAnchor2

getReactionForce

getReactionTorque

shift

getLinearSpeed

getAngularSpeed

getLinearTranslation

getAngularTranslation

getAxis

setSpringRestOffset

getSpringRestOffset

isMotorEnabled

setMotorEnabled

getMotorSpeed

setMotorSpeed

isMaximumMotorTorqueEnabled

setMaximumMotorTorqueEnabled

getMaximumMotorTorque

setMaximumMotorTorque

getMotorTorque

getSpringDampingRatio

setSpringDampingRatio

getSpringFrequency

getSpringStiffness

setSpringFrequency

setSpringStiffness

getMaximumSpringForce

setMaximumSpringForce

isMaximumSpringForceEnabled

setMaximumSpringForceEnabled

isSpringEnabled

setSpringEnabled

isSpringDamperEnabled

setSpringDamperEnabled

getSpringForce