Class HandConstraint

Provides a solver that constrains the target to a region safe for hand constrained interactive content. This solver is intended to work with IMixedRealityHand but also works with IMixedRealityController.

Inheritance
Object
Solver
HandConstraint
HandConstraintPalmUp
Inherited Members
Namespace: Microsoft.MixedReality.Toolkit.Utilities.Solvers
Assembly: cs.temp.dll.dll
Syntax
public class HandConstraint : Solver

Fields

handBounds

Declaration
protected HandBounds handBounds
Field Value
Type Description
HandBounds

trackedController

Declaration
protected IMixedRealityController trackedController
Field Value
Type Description
IMixedRealityController

Properties

HideHandCursorsOnActivate

When a hand is activated for tracking, should the cursor(s) be disabled on that hand?

Declaration
public bool HideHandCursorsOnActivate { get; set; }
Property Value
Type Description
Boolean

OffsetBehavior

Specifies how the solver's offset relative to the hand will be computed.

Declaration
public HandConstraint.SolverOffsetBehavior OffsetBehavior { get; set; }
Property Value
Type Description
HandConstraint.SolverOffsetBehavior

OnFirstHandDetected

Event which is triggered when zero hands to one hand is tracked.

Declaration
public UnityEvent OnFirstHandDetected { get; set; }
Property Value
Type Description
UnityEvent

OnHandActivate

Event which is triggered when a hand begins being tracked.

Declaration
public UnityEvent OnHandActivate { get; set; }
Property Value
Type Description
UnityEvent

OnHandDeactivate

Event which is triggered when a hand stops being tracked.

Declaration
public UnityEvent OnHandDeactivate { get; set; }
Property Value
Type Description
UnityEvent

OnLastHandLost

Event which is triggered when all hands are lost.

Declaration
public UnityEvent OnLastHandLost { get; set; }
Property Value
Type Description
UnityEvent

RotationBehavior

Specifies how the solver should rotate when tracking the hand.

Declaration
public HandConstraint.SolverRotationBehavior RotationBehavior { get; set; }
Property Value
Type Description
HandConstraint.SolverRotationBehavior

SafeZone

Which part of the hand to move the tracked object towards. The ulnar side of the hand is recommended for most situations.

Declaration
public HandConstraint.SolverSafeZone SafeZone { get; set; }
Property Value
Type Description
HandConstraint.SolverSafeZone

SafeZoneBuffer

Additional offset to apply to the intersection point with the hand bounds.

Declaration
public float SafeZoneBuffer { get; set; }
Property Value
Type Description
Single

UpdateWhenOppositeHandNear

Should the solver continue to move when the opposite hand (hand which is not being tracked) is near the tracked hand. This can improve stability when one hand occludes the other."

Declaration
public bool UpdateWhenOppositeHandNear { get; set; }
Property Value
Type Description
Boolean

Methods

CalculateGoalPosition()

Performs a ray vs AABB test to determine where the solver can constrain the tracked object without intersection. The "safe zone" is calculated as if projected into the horizontal and vertical plane of the camera.

Declaration
protected virtual Vector3 CalculateGoalPosition()
Returns
Type Description
Vector3

The new goal position.

CalculateGoalRotation()

Determines the solver's goal rotation based off of the SolverRotationBehavior.

Declaration
protected virtual Quaternion CalculateGoalRotation()
Returns
Type Description
Quaternion

The new goal rotation.

GetController(Handedness)

Returns the first detected controller in the input system that matches the passed-in handedness

Declaration
protected static IMixedRealityController GetController(Handedness handedness)
Parameters
Type Name Description
Handedness handedness

The handedness of the returned controller
Returns
Type Description
IMixedRealityController

The IMixedRealityController for the desired handedness, or null if none are present.

IsOppositeHandNear(IMixedRealityController)

Performs an intersection test to see if the left hand is near the right hand or vice versa.

Declaration
protected virtual bool IsOppositeHandNear(IMixedRealityController controller)
Parameters
Type Name Description
IMixedRealityController controller

The hand to check against.
Returns
Type Description
Boolean

True, when hands are near each other.

IsValidController(IMixedRealityController)

Determines if a hand meets the requirements for use with constraining the tracked object.

Declaration
protected virtual bool IsValidController(IMixedRealityController controller)
Parameters
Type Name Description
IMixedRealityController controller

The controller to check against.
Returns
Type Description
Boolean

True if this hand should be used from tracking.

OnEnable()

Declaration
protected override void OnEnable()
Overrides

SolverUpdate()

Should be implemented in derived classes, but Solver can be used to flush shared transform to real transform

Declaration
public override void SolverUpdate()
Overrides

ToggleCursors(IMixedRealityController, Boolean, Boolean)

Enables/disables all cursors on the currently tracked hand.

Declaration
protected virtual IEnumerator ToggleCursors(IMixedRealityController controller, bool visible, bool frameDelay = false)
Parameters
Type Name Description
IMixedRealityController controller

Controller target to search for pointers
Boolean visible

Is the cursor visible?
Boolean frameDelay

Delay one frame before performing the toggle to allow the pointers to instantiate their cursors.
Returns
Type Description
IEnumerator