API reference
HandGrabInteractor Class
Extends PointerInteractor< HandGrabInteractor, HandGrabInteractable >, IHandGrabInteractor, IRigidbodyRef
Enables hand grab for objects within arm's reach that have a <cref="GrabInteractable" />.
When grabbing an object, the hands visually snap to any <cref="HandPose" /> you've provided. To enable grab for controllers, use GrabInteractor.
Properties
IHand Hand[Get]
bool HoverOnZeroStrength[Get]
IThrowVelocityCalculator VelocityCalculator[Get]
IMovement Movement[Get]
bool MovementFinished[Get]
HandGrabTarget HandGrabTarget[Get]
float FingersStrength[Get]
float WristStrength[Get]
Pose WristToGrabPoseOffset[Get]
Fields
Transform WristPoint[Get]
Transform PinchPoint[Get]
Transform PalmPoint[Get]
HandGrabAPI HandGrabApi[Get]
GrabTypeFlags SupportedGrabTypes[Get]
IHandGrabInteractable TargetInteractable[Get]
bool IsGrabbing[Get]
Rigidbody Rigidbody[Get]
Member Functions
HandFingerFlags GrabbingFingers ( )
Returns the fingers that are grabbing the interactable.
override bool CanSelect
( HandGrabInteractable interactable )
void ForceSelect
( HandGrabInteractable interactable,
bool allowManualRelease )
Forces the interactor to select the passed interactable, which will be grabbed in the next interaction iteration.
Parameters
interactable
The interactable to grab.
allowManualRelease
If false, the interactable can only be released by calling ForceRelease.
void ForceRelease ( )
Forces the interactor to deselect the currently grabbed interactable (if any).
override void SetComputeCandidateOverride
( Func< HandGrabInteractable > computeCandidate,
bool shouldClearOverrideOnSelect )
override void Unselect ( )
void InjectAllHandGrabInteractor
( HandGrabAPI handGrabApi,
Transform grabOrigin,
IHand hand,
Rigidbody rigidbody,
GrabTypeFlags supportedGrabTypes )
Adds everything contained in <cref="HandGrabInteractor"/> to a dynamically instantiated GameObject.
void InjectHandGrabApi
( HandGrabAPI handGrabAPI )
Adds a <cref="HandGrabAPI" /> to a dynamically instantiated GameObject.
void InjectHand
( IHand hand )
Adds a <cref="IHand" /> to a dynamically instantiated GameObject.
void InjectRigidbody
( Rigidbody rigidbody )
Adds a Rigidbody to a dynamically instantiated GameObject.
void InjectSupportedGrabTypes
( GrabTypeFlags supportedGrabTypes )
Adds a list of <cref="GrabTypeFlags" /> to a dynamically instantiated GameObject.
void InjectGrabOrigin
( Transform grabOrigin )
Adds a grab origin to a dynamically instantiated GameObject.
void InjectOptionalGripPoint
( Transform gripPoint )
Adds a grip point to a dynamically instantiated GameObject.
void InjectOptionalGripCollider
( Collider gripCollider )
Adds a grip collider to a dynamically instantiated GameObject.
void InjectOptionalPinchPoint
( Transform pinchPoint )
Adds a pinch point to a dynamically instantiated GameObject.
void InjectOptionalPinchCollider
( Collider pinchCollider )
Adds a pinch collider to a dynamically instantiated GameObject.
void InjectOptionalVelocityCalculator
( IThrowVelocityCalculator velocityCalculator )
Adds a velocity calculator to a dynamically instantiated GameObject.
Protected Functions
virtual void Reset ( )
override void Awake ( )
override void Start ( )
override void DoHoverUpdate ( )
Each call while the interactor is hovering, it checks whether there is an interaction being hovered and sets the target snap pose to it.
In the HandToObject snapping behaviors this is relevant as the hand can approach the object progressively even before a true grab starts.
override void InteractableSet
( HandGrabInteractable interactable )
override void InteractableUnset
( HandGrabInteractable interactable )
override void DoSelectUpdate ( )
Each call while the hand is selecting/grabbing an interactable, it moves the item to the new position while also attracting it towards the hand if the snapping mode requires it.
In some cases the parameter can be null, for example if the selection was interrupted by another hand grabbing the object. In those cases it will come out of the release state once the grabbing gesture properly finishes.
override void InteractableSelected
( HandGrabInteractable interactable )
When a new interactable is selected, start the grab at the ideal point.
When snapping is involved that can be a point in the interactable offset from the hand which will be stored to progressively reduced it in the next updates, effectively attracting the object towards the hand. When no snapping is involved the point will be the grip point of the hand directly. Note: ideally this code would be in InteractableSelected but it needs to be called before the object is marked as active.
Parameters
interactable
The selected interactable
override void InteractableUnselected
( HandGrabInteractable interactable )
When releasing an active interactable, calculate the releasing point in similar fashion to InteractableSelected.
Parameters
interactable
The released interactable
virtual override void HandlePointerEventRaised
( PointerEvent evt )
virtual override Pose ComputePointerPose ( )
override bool ComputeShouldSelect ( )
override bool ComputeShouldUnselect ( )
override HandGrabInteractable ComputeCandidate ( )
Compute the best interactable to snap to.
In order to do it the method measures the score from the current grip pose to the closes pose in the surfaces of each one of the interactables in the registry. Even though it returns the best interactable, it also saves the entire Snap pose to it in which the exact pose within the surface is already recorded to avoid recalculations within the same frame.
Returns
The best interactable to snap the hand to.
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