API reference
HandGrabUseInteractor Class
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
IHand Hand[Get]
The IHand used for both grabbing and using.
Though HandGrabUseInteractor is not an IHandGrabInteractor, this property is contractually similar to IHandGrabInteractor.Hand.
IFingerUseAPI UseAPI[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
HandGrabTarget HandGrabTarget[Get]
The HandGrab.HandGrabTarget used by this interactor when grabbing.
bool IsGrabbing[Get]
Implementation of IHandGrabState.IsGrabbing; for details, please refer to the related documentation provided for that interface.
float WristStrength[Get]
Implementation of IHandGrabState.WristStrength; for details, please refer to the related documentation provided for that interface.
float FingersStrength[Get]
Implementation of IHandGrabState.FingersStrength; for details, please refer to the related documentation provided for that interface.
Pose WristToGrabPoseOffset[Get]
Implementation of IHandGrabState.WristToGrabPoseOffset; for details, please refer to the related documentation provided for that interface.
Action< IHandGrabState > WhenHandGrabStarted[Get]
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.
Action< IHandGrabState > WhenHandGrabEnded[Get]
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.
Protected Functions
virtual override bool ComputeShouldSelect ( )
virtual override bool ComputeShouldUnselect ( )
virtual override void Awake ( )
virtual override void Start ( )
override void InteractableSelected
( HandGrabUseInteractable interactable )
override void InteractableUnselected
( HandGrabUseInteractable interactable )
virtual override void DoHoverUpdate ( )
virtual override void DoSelectUpdate ( )
virtual override HandGrabUseInteractable ComputeCandidate ( )
Member Functions
HandFingerFlags GrabbingFingers ( )
Implementation of IHandGrabState.GrabbingFingers; for details, please refer to the related documentation provided for that interface.
void InjectAllHandGrabUseInteractor
( IFingerUseAPI 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.
void InjectUseApi
( IFingerUseAPI 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.
void InjectOptionalHand
( IHand 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.
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