Class XRDualGrabFreeTransformer

Grab transformer which supports moving and rotating unconstrained with multiple Interactors. Maintains the offset from the attachment points used for each Interactor and points in the direction made by each grab. This is the default grab transformer used for multiple selections.

Inheritance
Object
Object
Component
Behaviour
MonoBehaviour
XRBaseGrabTransformer
XRDualGrabFreeTransformer
Inherited Members
UnityEngine.Component.GetComponentInParent<T>(System.Boolean)
UnityEngine.Object.FindObjectsByType<T>(UnityEngine.FindObjectsSortMode)
UnityEngine.Object.FindObjectsOfType<T>(System.Boolean)
UnityEngine.Object.FindObjectsByType<T>(UnityEngine.FindObjectsInactive, UnityEngine.FindObjectsSortMode)
UnityEngine.Object.FindObjectOfType<T>(System.Boolean)
UnityEngine.Object.FindFirstObjectByType<T>()
UnityEngine.Object.FindAnyObjectByType<T>()
UnityEngine.Object.FindFirstObjectByType<T>(UnityEngine.FindObjectsInactive)
UnityEngine.Object.FindAnyObjectByType<T>(UnityEngine.FindObjectsInactive)
Namespace: UnityEngine.XR.Interaction.Toolkit.Transformers
Syntax
[AddComponentMenu("XR/Transformers/XR Dual Grab Free Transformer", 11)]
[HelpURL("https://docs.unity3d.com/Packages/com.unity.xr.interaction.toolkit@2.3/api/UnityEngine.XR.Interaction.Toolkit.Transformers.XRDualGrabFreeTransformer.html")]
public class XRDualGrabFreeTransformer : XRBaseGrabTransformer, IXRGrabTransformer
Remarks

When there is a single Interactor, this has identical behavior to XRSingleGrabFreeTransformer.

Properties

multiSelectPosition

Controls how multiple interactors combine to drive this interactable's position

Declaration
public XRDualGrabFreeTransformer.PoseContributor multiSelectPosition { get; set; }
Property Value
Type Description
XRDualGrabFreeTransformer.PoseContributor
See Also

multiSelectRotation

Controls how multiple interactors combine to drive this interactable's rotation

Declaration
public XRDualGrabFreeTransformer.PoseContributor multiSelectRotation { get; set; }
Property Value
Type Description
XRDualGrabFreeTransformer.PoseContributor
See Also

registrationMode

Controls how this grab transformer will be registered automatically at startup.

Declaration
protected override XRBaseGrabTransformer.RegistrationMode registrationMode { get; }
Property Value
Type Description
XRBaseGrabTransformer.RegistrationMode
Overrides
Remarks

This can be overridden in derived classes.
If you want your derived class to register as a Multiple Grab Transformer:

protected override RegisterMode registrationMode => RegisterMode.Multiple;

See Also

Methods

OnDrawGizmosSelected()

See MonoBehaviour.

Declaration
protected virtual void OnDrawGizmosSelected()

OnGrabCountChanged(XRGrabInteractable, Pose, Vector3)

Called by Unity each time the number of selections changes for the given Interactable while grabbed by at least one Interactor, including when it is first grabbed. Use this to do any code initialization based on each Interactor currently selecting the Interactable, for example computing the initial distance between both Interactors grabbing the object.

Declaration
public override void OnGrabCountChanged(XRGrabInteractable grabInteractable, Pose targetPose, Vector3 localScale)
Parameters
Type Name Description
XRGrabInteractable grabInteractable

The XR Grab Interactable being grabbed.
Pose targetPose

The current target pose for the current frame.
Vector3 localScale

The current scale of the Interactable's transform relative to the GameObjects parent.
Overrides
Remarks

There will always be at least one Interactor selecting the Interactable when this method is called. In other words, this will be called when the selection count changes from 0 to 1 and whenever it subsequently changes while still above 0. This method is called by Unity right before Process(XRGrabInteractable, XRInteractionUpdateOrder.UpdatePhase, ref Pose, ref Vector3) if the selection count changed.
To get the number of Interactors selecting the Interactable in your implementation method:

grabInteractable.interactorsSelecting.Count

Process(XRGrabInteractable, XRInteractionUpdateOrder.UpdatePhase, ref Pose, ref Vector3)

Called by the linked Interactable to calculate the target pose and scale. Modify the value of targetPose and/or localScale (or neither).

Declaration
public override void Process(XRGrabInteractable grabInteractable, XRInteractionUpdateOrder.UpdatePhase updatePhase, ref Pose targetPose, ref Vector3 localScale)
Parameters
Type Name Description
XRGrabInteractable grabInteractable

The XR Grab Interactable to calculate the target pose and scale for.
XRInteractionUpdateOrder.UpdatePhase updatePhase

The update phase this is called during.
Pose targetPose

The target pose for the current frame.
Vector3 localScale

The scale of the Interactable's transform relative to the GameObjects parent.
Overrides
Remarks

When there is more than one linked grab transformer that can process, the updated value of each ref parameter is passed to each in series according to its order in the list. You can utilize this by, for example, having the first grab transformer compute the target pose, and the second compute just the scale.
If your transformer requires the use of two or more selections, you should first check for that condition in your implementation method:

if (grabInteractable.interactorsSelecting.Count < 2) return;

See Also

See Also