Continuous interactable and XRPokeFilter play nice with each other

Documentation~/docs/usage.md

@@ -3,10 +3,10 @@ This can be imported as a git package in Unity. The package is built to use [Uni
 
 ## Scene setup
 - Setup the Scene with an XR Origin & XR Interaction Manager (see documentation [XRI documentation for more details](https://docs.unity3d.com/Packages/[email protected]/manual/general-setup.html#create-the-xr-origin-camera-rig-for-tracked-devices)).
-- Add the `HandJointData` in the scene.
 - Setup the `HPUIInteractor`
   - For each hand, add `hpuiinteractorright` and `HPUIInteractorLeft` prefabs to the scene.
 - Setup an HPUI Interactable. (TODO)
+  - HPUIInteractor is an extention of `XRPokeInteractor`. You would be able to use `XRPokeFilter` on any of the HPUI Interactables. Note that, with the `HPUIContinuousInteractable`, the associated `XRPokeFilter` needs to be enabled after the surface is created. By default, once the surface is created, it will enable any XRPokeFilter component on the same GameObject, right before `continuousSurfaceCreatedEvent` is invoked.
 
 ## Interactables
 TODO

Runtime/Interaction/HPUIContinuousInteractable.cs

@@ -4,6 +4,7 @@
 using UnityEngine;
 using UnityEngine.XR.Hands;
 using UnityEngine.XR.Interaction.Toolkit;
+using UnityEngine.XR.Interaction.Toolkit.Filtering;
 
 namespace ubco.ovilab.HPUI.Interaction
 {
@@ -68,6 +69,10 @@ protected override void Awake()
         /// <inheritdoc />
         public override Transform GetAttachTransform(IXRInteractor interactor)
         {
+            if (interactor == null)
+            {
+                return this.transform;
+            }
             // NOTE: This also should allow the XRPokeFilter to work with ContinuousInteractable, I think!
             return GetDistance(interactor.GetAttachTransform(this).transform.position).collider.transform;
         }
@@ -182,6 +187,11 @@ private IEnumerator DelayedExecuteCalibration(float x_size, float y_size, List<T
             OnDisable();
             OnEnable();
 
+            XRPokeFilter pokeFilter = GetComponent<XRPokeFilter>();
+            if (pokeFilter != null)
+            {
+                pokeFilter.enabled = true;
+            }
             continuousSurfaceCreatedEvent?.Invoke(new HPUIContinuousSurfaceCreatedEventArgs(this));
         }
     }