API reference

HandGrabUseInteractor Class

Extends Interactor< HandGrabUseInteractor, HandGrabUseInteractable >
Implements IHandGrabState
This interactor allows sending use-strength values to an interactable to create use interactions.
For example, pressing a trigger, squeezing a ball, etc. In order to calculate the usage strength of a finger it uses a IFingerUseAPI. This class is also an IHandGrabState, so it can be attached to a SyntheticHand to drive the fingers rotations, lerping between the relaxed hand pose and the tight hand pose provided by the interactable depending on the progress of the action.

Properties

FingersStrength : float
[Get]
Implementation of IHandGrabState.FingersStrength; for details, please refer to the related documentation provided for that interface.
Signature 
float FingersStrength
Hand : IHand
[Get]
The IHand used for both grabbing and using.
Though HandGrabUseInteractor is not an IHandGrabInteractor, this property is contractually similar to IHandGrabInteractor.Hand.
Signature 
IHand Hand
HandGrabTarget : HandGrabTarget
[Get]
The HandGrab.HandGrabTarget used by this interactor when grabbing.
Signature 
HandGrabTarget HandGrabTarget
IsGrabbing : bool
[Get]
Implementation of IHandGrabState.IsGrabbing; for details, please refer to the related documentation provided for that interface.
Signature 
bool IsGrabbing
UseAPI : IFingerUseAPI
[Get]
The IFingerUseAPI invoked by this interactor to determine the "finger use strength" of the Hand's fingers.
"Strength" in this context is a measure of of how similar/different the finger's state is to what the system considers "using"; a related overview of "strength" can be found in the documentation for IHand.GetFingerPinchStrength(HandFinger).
Signature 
IFingerUseAPI UseAPI
WhenHandGrabEnded : Action< IHandGrabState >
[Get][Set]
An event which could indicate that the current interactor (which would be passed to the event as an IHandGrabState) stopped grabbing.
In the current implementation, this event is never invoked. Instead, Interactor<TInteractor, TInteractable>.WhenStateChanged can be used to respond to the beginning of a grab; when that event is called with its argument's InteractorStateChangeArgs.PreviousState property set to InteractorState.Select, a grab interaction has ended.
Signature 
Action<IHandGrabState> WhenHandGrabEnded
WhenHandGrabStarted : Action< IHandGrabState >
[Get][Set]
An event which could indicate that the current interactor (which would be passed to the event as an IHandGrabState) began grabbing.
In the current implementation, this event is never invoked. Instead, Interactor<TInteractor, TInteractable>.WhenStateChanged can be used to respond to the beginning of a grab; when that event is called with its argument's InteractorStateChangeArgs.NewState property set to InteractorState.Select, a grab interaction has started.
Signature 
Action<IHandGrabState> WhenHandGrabStarted
WristStrength : float
[Get]
Implementation of IHandGrabState.WristStrength; for details, please refer to the related documentation provided for that interface.
Signature 
float WristStrength
WristToGrabPoseOffset : Pose
[Get]
Implementation of IHandGrabState.WristToGrabPoseOffset; for details, please refer to the related documentation provided for that interface.
Signature 
Pose WristToGrabPoseOffset

Protected Methods

Awake ()
Signature 
override void Awake()
Returns
override void
ComputeCandidate ()
Signature 
override HandGrabUseInteractable ComputeCandidate()
Returns
override HandGrabUseInteractable
ComputeShouldSelect ()
Signature 
override bool ComputeShouldSelect()
Returns
override bool
ComputeShouldUnselect ()
Signature 
override bool ComputeShouldUnselect()
Returns
override bool
DoHoverUpdate ()
Signature 
override void DoHoverUpdate()
Returns
override void
DoSelectUpdate ()
Signature 
override void DoSelectUpdate()
Returns
override void
InteractableSelected ( interactable )
Signature 
override void InteractableSelected(HandGrabUseInteractable interactable)
Parameters
interactable: HandGrabUseInteractable
Returns
override void
InteractableUnselected ( interactable )
Signature 
override void InteractableUnselected(HandGrabUseInteractable interactable)
Parameters
interactable: HandGrabUseInteractable
Returns
override void
Start ()
Signature 
override void Start()
Returns
override void

Methods

GrabbingFingers ()
Implementation of IHandGrabState.GrabbingFingers; for details, please refer to the related documentation provided for that interface.
Signature 
HandFingerFlags GrabbingFingers()
Returns
HandFingerFlags
InjectAllHandGrabUseInteractor ( useApi )
Adds all required scripts for a HandGrabUseInteractor to a dynamically instantiated GameObject.
This method exists to support Interaction SDK's dependency injection pattern and is not needed for typical Unity Editor-based usage.
Signature 
void InjectAllHandGrabUseInteractor(IFingerUseAPI useApi)
Parameters
useApi: IFingerUseAPI
Returns
void
InjectOptionalHand ( hand )
Adds an IHand to a dynamically instantiated GameObject.
This method exists to support Interaction SDK's dependency injection pattern and is not needed for typical Unity Editor-based usage.
Signature 
void InjectOptionalHand(IHand hand)
Parameters
hand: IHand
Returns
void
InjectUseApi ( useApi )
Adds an IFingerUseAPI to a dynamically instantiated GameObject.
This method exists to support Interaction SDK's dependency injection pattern and is not needed for typical Unity Editor-based usage.
Signature 
void InjectUseApi(IFingerUseAPI useApi)
Parameters
useApi: IFingerUseAPI
Returns
void
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