• Add XR Interaction Toolkit after importing, add the Samples :
•  Starter Assets and AR StarterAssets for enhanced interaction features in Unity.

6 – Enabled Touch Interaction Profile

• OpenXR Settings: Under XR Plug-in Management, select OpenXR.

• Android Platform: Ensure you’re configuring settings for the Android platform. If not, switch to Android in Build Settings.
• Add Oculus Touch Interaction Profile: In the OpenXR settings for Android, include the Oculus Touch profile to enable touch interaction.

7 -Project Validations

• In the Project Validation section, you might encounter warnings or errors. Click on Fix All to automatically address and resolve these issues.

2 Unity Scene Setup for Mixed Reality:

1. Clean Scene Setup:  Delete all objects in your Unity scene except for the Directional Light.
2. Add XROrigin (AR): Add an XROrigin (AR) object, which automatically includes the XR Interaction Manager.

1. 1. • Select XR Origin (XR Rig) > Camera Offset > Main Camera.
      • Set Camera Solid color alpha to 0 for passthrough.
      • Confirm the presence of AR Camera Manager and AR Camera Background components.

4 Configure XR Input:

• • Select the XROrigin in the scene.
  • In the Inspector, add the Input Action Manager component.
  • Provide a reference to the action assets: XRI Default Input Actions.

• Navigate to the XR Rig > Camera Offset > Left Controller.
• In the Inspector the XR Controller (Action-based) component, on the right side, click on the icon.
• Choose XRI Default Left Controller for the Left controller.
• Similarly, select XRI Default Right Controller for the Right controller.

5  AR Raycast and Plane Management:

• • Add AR Raycast Manager and AR Plane Manager components to the XROrigin.
  • In AR Plane Manager, set the Plane Prefab Reference to an AR Feathered Plane prefab.

6 Create Placement Object:

• • Create an empty object in the scene (e.g., MR Place Object).
  • Create a new C# script, e.g., PlaceObject, and attach it to MR Place Object.
    
    • In the script:

    • using UnityEngine;
      using UnityEngine.InputSystem;
      using UnityEngine.XR.ARFoundation;
      using UnityEngine.XR.Interaction.Toolkit;
      
      public class PlaceObject : MonoBehaviour
      {
          [SerializeField] private InputActionReference inputActionReference;
          [SerializeField] private XRRayInteractor xrRayInteractor;
          [SerializeField] private GameObject objectToPlace;
          private GameObject placedObject = null;
          [SerializeField] private ARPlaneManager arPlaneManager;
          private void OnEnable()
          {
              inputActionReference.action.performed += ActionOnperformed; 
          }
      
          private void OnDisable()
          {
              inputActionReference.action.performed -= ActionOnperformed; 
          }
      
          private void ActionOnperformed(InputAction.CallbackContext obj)
          {
              if (xrRayInteractor.TryGetCurrentARRaycastHit(out ARRaycastHit hit))
              {
                  if (placedObject == null)
                  {
                      placedObject = Instantiate(objectToPlace, hit.pose.position, hit.pose.rotation);
                      DisableAllPlanes();
                  }
                  else
                  {
                      placedObject.transform.position = hit.pose.position;
                      placedObject.transform.rotation = hit.pose.rotation;
                  }
              }
          }
      
          public void DisableAllPlanes()
          {
              arPlaneManager.enabled = false;
              foreach (ARPlane trackable in arPlaneManager.trackables)
              {
                  trackable.gameObject.SetActive(false);
              }
          }
      }

• • • Add a reference to InputActionReference for the right controller’s Activate button.

    • Reference the XRRayInteractor (use the right-hand controller or adjust as needed).
    • Select the prefab you want to spawn when the Activate button is pressed.

These steps establish the foundational elements for a mixed reality scene in Unity, incorporating AR tracking, raycasting, and object placement based on controller input. Customize references and prefabs according to your specific project requirements.