Class XRGeneralGrabTransformer

Grab transformer which supports moving and rotating unconstrained with one or two interactors. Also allows clamped or unclamped scaling when using two interactors. Allows axis constraints on translation. This is the default grab transformer.

Inheritance
object
Object
Component
Behaviour
MonoBehaviour
XRBaseGrabTransformer
XRGeneralGrabTransformer
Implements
Inherited Members
Object.FindObjectsByType<T>(FindObjectsSortMode)
Object.FindObjectsByType<T>(FindObjectsInactive, FindObjectsSortMode)
Object.FindFirstObjectByType<T>()
Object.FindAnyObjectByType<T>()
Object.FindFirstObjectByType<T>(FindObjectsInactive)
Object.FindAnyObjectByType<T>(FindObjectsInactive)
Namespace: UnityEngine.XR.Interaction.Toolkit.Transformers
Assembly: Unity.XR.Interaction.Toolkit.dll
Syntax
[AddComponentMenu("XR/Transformers/XR General Grab Transformer", 11)]
[HelpURL("https://docs.unity3d.com/Packages/com.unity.xr.interaction.toolkit@3.0/api/UnityEngine.XR.Interaction.Toolkit.Transformers.XRGeneralGrabTransformer.html")]
public class XRGeneralGrabTransformer : XRBaseGrabTransformer, IXRGrabTransformer

Properties

allowOneHandedScaling

Allow one handed scaling using the scale value provider if available.

Declaration
public bool allowOneHandedScaling { get; set; }
Property Value
Type Description
bool
See Also

allowTwoHandedRotation

Determines how rotation is calculated when using two hands for the grab interaction.

Declaration
public XRGeneralGrabTransformer.TwoHandedRotationMode allowTwoHandedRotation { get; set; }
Property Value
Type Description
XRGeneralGrabTransformer.TwoHandedRotationMode
See Also

allowTwoHandedScaling

Allow scaling when using multi-grab interaction.

Declaration
public bool allowTwoHandedScaling { get; set; }
Property Value
Type Description
bool
See Also

clampScaling

If enabled, scaling will abide by ratio ranges defined by minimumScaleRatio and maximumScaleRatio.

Declaration
public bool clampScaling { get; set; }
Property Value
Type Description
bool
See Also

constrainedAxisDisplacementMode

Determines how the constrained axis displacement mode is computed.

Declaration
public XRGeneralGrabTransformer.ConstrainedAxisDisplacementMode constrainedAxisDisplacementMode { get; set; }
Property Value
Type Description
XRGeneralGrabTransformer.ConstrainedAxisDisplacementMode
See Also

maximumScaleRatio

Maximum scale multiplier applied to the initial scale captured on start.

Declaration
public float maximumScaleRatio { get; set; }
Property Value
Type Description
float
See Also

minimumScaleRatio

Minimum scale multiplier applied to the initial scale captured on start.

Declaration
public float minimumScaleRatio { get; set; }
Property Value
Type Description
float
See Also

oneHandedScaleSpeed

Scaling speed over time for one handed scaling based on the IXRScaleValueProvider

Declaration
public float oneHandedScaleSpeed { get; set; }
Property Value
Type Description
float
See Also

permittedDisplacementAxes

Permitted axes for translation displacement relative to the object's initial rotation.

Declaration
public XRGeneralGrabTransformer.ManipulationAxes permittedDisplacementAxes { get; set; }
Property Value
Type Description
XRGeneralGrabTransformer.ManipulationAxes
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.

Examples

If you want your derived class to register as a Multiple Grab Transformer:

  protected override RegisterMode registrationMode => RegisterMode.Multiple;
See Also

scaleMultiplier

Scales the distance of displacement between interactors needed to modify the scale interactable.

Declaration
public float scaleMultiplier { get; set; }
Property Value
Type Description
float
See Also

thresholdMoveRatioForScale

(Two Handed Scaling) Percentage as a measure of 0 to 1 of scaled relative hand displacement required to trigger scale operation. If this value is 0f, scaling happens the moment both grab interactors move closer or further away from each other. Otherwise, this percentage is used as a threshold before any scaling happens.

Declaration
public float thresholdMoveRatioForScale { get; set; }
Property Value
Type Description
float
See Also

Methods

Awake()

See MonoBehaviour.

Declaration
protected void Awake()
See Also

OnGrab(XRGrabInteractable)

Called by Unity when the given Interactable is grabbed (in other words, when entering the Select state). This method won't be called again until the Interactable is released by every Interactor. Use this to do any code initialization based on the first Interactor that selects the Interactable.

Declaration
public override void OnGrab(XRGrabInteractable grabInteractable)
Parameters
Type Name Description
XRGrabInteractable grabInteractable

The XR Grab Interactable being grabbed.
Overrides
Remarks

In other words, this will be called when the selection count changes from 0 to 1.

See Also

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 target scale of the Interactable's transform relative to the GameObject's 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, UpdatePhase, ref Pose, ref Vector3) if the selection count changed.

Examples

To get the number of Interactors selecting the Interactable in your implementation method:

  grabInteractable.interactorsSelecting.Count
See Also

Process(XRGrabInteractable, 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 target scale of the Interactable's transform relative to the GameObject's 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.

Examples

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

Implements

See Also