Struct Constraint

A linear or angular constraint in 1, 2, or 3 dimensions.

Implements

IEquatable<Constraint>

Inherited Members

ValueType.ToString()

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: Unity.Physics

Assembly: Unity.Physics.dll

Syntax

public struct Constraint : IEquatable<Constraint>

Fields

ConstrainedAxes

The constrained axes.

Declaration

public bool3 ConstrainedAxes

Field Value

Type	Description
bool3

DampingRatio

The damping ratio.

Declaration

public float DampingRatio

Field Value

Type	Description
float

DefaultDampingRatio

The default damping ratio.

Declaration

public const float DefaultDampingRatio = 2530.126

Field Value

Type	Description
float

DefaultMaxImpulse

The default maximum impulse.

Declaration

public const float DefaultMaxImpulse = Infinity

Field Value

Type	Description
float

DefaultSpringDamping

Deprecated. Use DefaultDampingRatio instead.

The default damping ratio.

Declaration

[Obsolete("DefaultSpringDamping has been deprecated (RemovedAfter 2023-05-09). Use DefaultDampingRatio instead. (UnityUpgradable) -> DefaultDampingRatio", false)]
public const float DefaultSpringDamping = 2530.126

Field Value

Type	Description
float

DefaultSpringFrequency

The default spring frequency.

(Immutable) Current default values give tau = 0.6 damping = 0.99 at 60hz The values are huge and we can't get damping = 1 -- a stiff constraint is the limit of a damped spring as spring params go to infinity. Rather than baking them these values could be calculated using JacobianUtilities.CalculateSpringFrequencyAndDamping(0.6f, 0.99f, math.rcp(60.0f), 4, out DefaultSpringFrequency, out DefaultDampingRatio);

Declaration

public const float DefaultSpringFrequency = 74341.31

Field Value

Type	Description
float

Max

The maximum.

Declaration

public float Max

Field Value

Type	Description
float

MaxImpulse

The impulse threshold after which ImpulseEvent will be raised from this constraint. In case of motorized constraints, represents the maximum impulse that can be applied to it during one step.

Declaration

public float3 MaxImpulse

Field Value

Type	Description
float3

Min

The minimum.

Declaration

public float Min

Field Value

Type	Description
float

SpringDamping

Deprecated. Use DampingRatio instead.

The spring damping ratio.

Declaration

[Obsolete("SpringDamping has been deprecated (RemovedAfter 2023-05-09). Use DampingRatio instead. (UnityUpgradable) -> DampingRatio", false)]
public float SpringDamping

Field Value

Type	Description
float

SpringFrequency

The spring frequency.

Declaration

public float SpringFrequency

Field Value

Type	Description
float

Target

The target a motor will drive towards. Can be set to zero for non-motor type constraints

Declaration

public float3 Target

Field Value

Type	Description
float3

Type

The constraint type.

Declaration

public ConstraintType Type

Field Value

Type	Description
ConstraintType

Properties

ConstrainedAxis1D

Selects the constrained axis from a constraint with Dimension == 1

Declaration

public int ConstrainedAxis1D { get; }

Property Value

Type	Description
int

Dimension

Number of affected degrees of freedom. 1, 2, or 3.

Declaration

public int Dimension { get; }

Property Value

Type	Description
int

FreeAxis2D

Selects the free axis from a constraint with Dimension == 2

Declaration

public int FreeAxis2D { get; }

Property Value

Type	Description
int

Methods

AngularVelocityMotor(float, float, float, float)

Drives bodies to a specified target angular velocity, around one axis.

Declaration

public static Constraint AngularVelocityMotor(float target, float maxImpulseOfMotor = Infinity, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	target	The target angular velocity of the motor around Joint's Axis, in rad/s.
float	maxImpulseOfMotor	The magnitude of the max impulse that a motor constraint can exert in a single step. Must be positive. This is a motor specific usage that does not represent the impulse threshold for event reporting.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

BallAndSocket(float, float)

Constrains linear motion about all three axes to zero.

Declaration

public static Constraint BallAndSocket(float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

BallAndSocket(float3, float, float)

Constrains linear motion about all three axes to zero.

Declaration

public static Constraint BallAndSocket(float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Cone(int, FloatRange, float, float)

Constrains angular motion about two axes within the specified range. Rotation around the third is unrestricted.

Declaration

public static Constraint Cone(int freeAxis, Math.FloatRange angularRange, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis specifying the height of the cone within which the  bodies may rotate.
Math.FloatRange	angularRange	The minimum required angle and maximum possible angle between the free axis and its bind pose orientation. A minimum value of zero produces a conical range of motion, while a minimum value greater than zero results in motion restricted to the intersection of the inner and outer cones.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Cone(int, FloatRange, float3, float, float)

Constrains angular motion about two axes within the specified range. Rotation around the third is unrestricted.

Declaration

public static Constraint Cone(int freeAxis, Math.FloatRange angularRange, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis specifying the height of the cone within which the  bodies may rotate.
Math.FloatRange	angularRange	The minimum required angle and maximum possible angle between the free axis and its bind pose orientation. A minimum value of zero produces a conical range of motion, while a minimum value greater than zero results in motion restricted to the intersection of the inner and outer cones.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Cylindrical(int, FloatRange, float, float)

Constrains linear motion about two axes within the specified range. Movement about the third is unrestricted.

Declaration

public static Constraint Cylindrical(int freeAxis, Math.FloatRange distanceRange, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis along which the bodies may freely translate.
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies about the two constrained axes. A minimum value of zero produces a cylindrical range of motion, while a minimum value greater than zero results in a tube-shaped range of motion.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Cylindrical(int, FloatRange, float3, float, float)

Constrains linear motion about two axes within the specified range. Movement about the third is unrestricted.

Declaration

public static Constraint Cylindrical(int freeAxis, Math.FloatRange distanceRange, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis along which the bodies may freely translate.
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies about the two constrained axes. A minimum value of zero produces a cylindrical range of motion, while a minimum value greater than zero results in a tube-shaped range of motion.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Equals(object)

Tests if this object is considered equal to another.

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
object	obj	The object to compare to this object.

Returns

Type	Description
bool	True if the objects are considered equal, false if they are not.

Overrides

ValueType.Equals(object)

Equals(Constraint)

Tests if this Constraint is considered equal to another.

Declaration

public bool Equals(Constraint other)

Parameters

Type	Name	Description
Constraint	other	The constraint to compare to this object.

Returns

Type	Description
bool	True if the objects are considered equal, false if they are not.

FixedAngle(float, float)

Constrains angular motion about all three axes to zero.

Declaration

public static Constraint FixedAngle(float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

FixedAngle(float3, float, float)

Constrains angular motion about all three axes to zero.

Declaration

public static Constraint FixedAngle(float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

GetHashCode()

Calculates a hash code for this object.

Declaration

public override int GetHashCode()

Returns

Type	Description
int	A hash code for this object.

Overrides

ValueType.GetHashCode()

Hinge(int, float, float)

Constrains angular motion about two axes to zero. Rotation around the third is unrestricted.

Declaration

public static Constraint Hinge(int freeAxis, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis around which the bodies may freely rotate.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Hinge(int, float3, float, float)

Constrains angular motion about two axes to zero. Rotation around the third is unrestricted.

Declaration

public static Constraint Hinge(int freeAxis, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	freeAxis	The axis around which the bodies may freely rotate.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

LimitedDistance(FloatRange, float, float)

Constrains linear motion about all three axes within the specified range.

Declaration

public static Constraint LimitedDistance(Math.FloatRange distanceRange, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

LimitedDistance(FloatRange, float3, float, float)

Constrains linear motion about all three axes within the specified range.

Declaration

public static Constraint LimitedDistance(Math.FloatRange distanceRange, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

LinearVelocityMotor(float, float, float, float)

Drives bodies to a specified target relative velocity, along one axis.

Declaration

public static Constraint LinearVelocityMotor(float target, float maxImpulseOfMotor = Infinity, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	target	The target velocity for the motor (along Joint's Axis).
float	maxImpulseOfMotor	The magnitude of the max impulse that a motor constraint can exert in a single step. Must be positive. This is a motor specific usage that does not represent the impulse threshold for event reporting.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A constraint.

MotorPlanar(float, float, float, float)

Moves bodies along one axis to specified target distance. Movement about the other two perpendicular axes is unrestricted.

Declaration

public static Constraint MotorPlanar(float target, float maxImpulseOfMotor = Infinity, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	target	The target distance the motor drives towards (along Joint's Axis).
float	maxImpulseOfMotor	The magnitude of the max impulse that a motor constraint can exert in a single step. Must be positive. This is a motor specific usage that does not represent the impulse threshold for event reporting.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A constraint

MotorTwist(float, float, float, float)

Constrains angular motion about one axis and locks the angle at the specified target rotation.

Declaration

public static Constraint MotorTwist(float target, float maxImpulseOfMotor = Infinity, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	target	The target rotation around Joint's Axis the motor is driving towards, in radians.
float	maxImpulseOfMotor	The magnitude of the max impulse that a motor constraint can exert in a single step. Must be positive. This is a motor specific usage that does not represent the impulse threshold for event reporting.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A constraint.

MotorTwist(float, FloatRange, float, float, float)

Constrains angular motion about one axis and locks the angle at the specified target rotation while limiting the motion range.

Declaration

public static Constraint MotorTwist(float target, Math.FloatRange angleRange, float maxImpulseOfMotor = Infinity, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
float	target	The target rotation around Joint's Axis the motor is driving towards, in radians.
Math.FloatRange	angleRange	The minimum required angle and maximum possible angle of rotation of the constrained bodies about the constraint's axis, in radians.
float	maxImpulseOfMotor	The magnitude of the max impulse that a motor constraint can exert in a single step. Must be positive. This is a motor specific usage that does not represent the impulse threshold for event reporting.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A constraint.

Planar(int, FloatRange, float, float)

Constrains linear motion about one axis within the specified range. Movement about the other two is unrestricted.

Declaration

public static Constraint Planar(int limitedAxis, Math.FloatRange distanceRange, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	limitedAxis	The axis along which the bodies' translation is restricted.
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies about the constrained axis. Identical minimum and maximum values result in a plane, while different values constrain the bodies between two parallel planes.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Planar(int, FloatRange, float3, float, float)

Constrains linear motion about one axis within the specified range. Movement about the other two is unrestricted.

Declaration

public static Constraint Planar(int limitedAxis, Math.FloatRange distanceRange, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	limitedAxis	The axis along which the bodies' translation is restricted.
Math.FloatRange	distanceRange	The minimum required distance and maximum possible distance between the constrained bodies about the constrained axis. Identical minimum and maximum values result in a plane, while different values constrain the bodies between two parallel planes.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Twist(int, FloatRange, float, float)

Constrains angular motion about one axis within the specified range.

Declaration

public static Constraint Twist(int limitedAxis, Math.FloatRange angularRange, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	limitedAxis	The axis around which the bodies' rotation is restricted.
Math.FloatRange	angularRange	The minimum required angle and maximum possible angle of rotation between the constrained bodies around the constrained axis.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Twist(int, FloatRange, float3, float, float)

Constrains angular motion about one axis within the specified range.

Declaration

public static Constraint Twist(int limitedAxis, Math.FloatRange angularRange, float3 impulseEventThreshold, float springFrequency = 74341.31, float dampingRatio = 2530.126)

Parameters

Type	Name	Description
int	limitedAxis	The axis around which the bodies' rotation is restricted.
Math.FloatRange	angularRange	The minimum required angle and maximum possible angle of rotation between the constrained bodies around the constrained axis.
float3	impulseEventThreshold	The minimum impulse needed to receive an impulse event for this constraint.
float	springFrequency	The spring frequency used to relax this constraint.
float	dampingRatio	The damping ratio used to relax this constraint.

Returns

Type	Description
Constraint	A Constraint.

Implements

IEquatable<T>