This workshop will show you how to:

Final Result

To complete this workshop you will need:

Languages used:

Additional resources

The onboarding experience is an important aspect of any AR app. Its main purpose is to provide users with straightforward information on how to use the app. While each application will have specific instructions, the initial steps (e.g., finding a plane, placing an object) are commonly used in any application. There are no specific rules on how the onboarding experience needs to be; the important part is that the user needs to be informed from the beginning about what they need to do to use the application (e.g., which button to press, which actions to perform).

Overlays video

One effective solution is to add overlaid videos and/or text to alert the user. Both uGUI and UIToolkit can be used for displaying and controlling the user interface. In this tutorial, we are going to use the new uGUI system.

Canvas Screen space

Before building the UI we need to import the onboarding AR videos. Import the findaplane.webm and taptoplace.webm in a subfolder of the Assets.

Inside the same subfolder create a RenderTexture named UXRenderTextureand change the size to 512 x 512 in the Inspector window and Anti-aliasing to 2 samples

Render Texture

Create a new UI -> Canvas and change the name to Onboarding

Create Canvas

In the Inspector Window:

Create a new Empty Game Object inside the Canvas GameObject and name it UIRoot this is going to be the container of the UI.

With the UIRoot selected, in the Inspector Window:

UIRoot element

We can now add the actual components that hold the UX information, a UI -> Text - TextMeshPro, named Info1, an Empty Game Object named Video and another UI -> Text - TextMeshPro named Info2. The order of these components in the Hierarchy Panel is important.

With both Info1 and Info2 selected, in the Inspector Window:

Select the Info1 GameObject and in the TextMeshPro - Text (UI) component change the text input to:

Similarly, for the Info2, change the text to:

Select the the Video GameObject, and in the Inspector Window:

Finally, add to the Video GameObject a new UI -> Raw Image and named it videoUX, and in the Inspector Window:

Video Player UI

Press Play, you should be able to see the UI interface and the video running in the centre

Play video UI

Control the UI

The final step is to make the UI respond to the underlying ARFoundation system. This involves changing the text and video when the surface is found and removing the interface once the user places the object. This functionality is controlled by a new C# script.

Create a new script named uiAR

using UnityEngine;
using UnityEngine.Video;
using UnityEngine.XR.ARFoundation;
using TMPro;

//Script need to be added to XROrigin, as it has ARPlaneManager and tapToPlace
public class uiAR : MonoBehaviour
{
    //Video player
    public VideoPlayer videoUX;
    //Video Clips
    public VideoClip v_findSurface;
    public VideoClip v_tapPlace;
    //Info texts
    public TextMeshProUGUI t_info1;
    public TextMeshProUGUI t_info2;

    // Events for found plane and content created
    private ARPlaneManager m_ARPlaneManager; //ARFoundation system
    private tapToPlace m_tapToPlace; //used to detect when the user create the content

    bool isContentVisible = false;

    // Start is called before the first frame update
    private void Awake()
    {
        videoUX.clip = v_findSurface;
        m_ARPlaneManager = GetComponent<ARPlaneManager>();
        m_ARPlaneManager.planesChanged += planeFound; //Subscribe to the event `plane is detected`

        m_tapToPlace = GetComponent<tapToPlace>();
        m_tapToPlace._contentVisibleEvent += contentVisible; //Subscribe to the event `content is created` (user Tap)
    }

    void planeFound(ARPlanesChangedEventArgs args)
    {
        //Plane found, turn off UI and Video
        videoUX.clip = v_tapPlace;
        t_info1.text = "Tap to Place";
        t_info2.text = "Surface found";
        m_ARPlaneManager.planesChanged -= planeFound; //Unsubcribe

        if (isContentVisible)
        {   //Content created, turn off UI and Video
            videoUX.gameObject.SetActive(false);
            t_info1.gameObject.SetActive(false);
            t_info2.gameObject.SetActive(false);
        }

    }

    void contentVisible()
    {
        isContentVisible = true; //if the content is visible
        m_tapToPlace._contentVisibleEvent -= contentVisible; //Unsubscribe

        //Content created, turn off UI and Video
        videoUX.gameObject.SetActive(false);
        t_info1.gameObject.SetActive(false);
        t_info2.gameObject.SetActive(false);
    }
}

Add the script to the XR Origin GameObject and set the public variables
Play video UI

In order to see the script in action we need to build and deploy the App

Play video UI

The Lean Touch Asset provides a quick and easy way to add multiple gestures to your AR project without writing (almost) any code.

Installation is a two-step process, firstly you need to download the Unity Assets (there are two versions of LeanTouch, the Free version is enough for our needs) from the Unity Store, to add it to your asset collection.

Head to The Unity Store

Lean Touch

Secondly, install it in Unity by going to Window -> Package Manager

Package Manager

Search under Packages: My Assests for Lean Touch, download and import.

Install

Add the LeanTouch GameObject by right-clicking on the Hierarchy panelLean -> Touch

We now need to add the touch controls to our object (ARGauge) - there are numerous options and Lean Touch can be used for any application with a touch screen.

Double-click your AR Object Prefab to open it in Edit mode and Add Component. If you type in Lean you will see a long list of options. Our first one is Lean Selectable and we want to tick the Self Selected option - this simple makes sure our object is automatically selected and ready to touch.

As the Lean Drag Translate will be in conflict with the tapToPlace script, we can change the latter and use Lean touch for the input tap.

Open the tapToPlace script in VSCode (tapToPlace should be attached to XROrigin GameObject), comment out the Update function and add a new spawnObject() function. The timeThreshold variable is not used anymore

using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR.ARFoundation;
using UnityEngine.XR.ARSubsystems;

[RequireComponent(typeof(ARRaycastManager))]
public class tapToPlace : MonoBehaviour
{
    public GameObject gameObjectToInstantiate; //the Prefab GameObject to instantiate in the AR environment. To be added in the inspector window
    public GameObject spawnedObject; //the Prefab Instantiate in the scene. Used internally by the script 
    private ARRaycastManager _arRaycastManager; //part of the XROrigin
    private Vector2 touchPosition; //XZ position of the user Tap

    static List<ARRaycastHit> hits = new List<ARRaycastHit>();
    public float timeThreshold = 0.5f; //User need to tap and hold the finger for at least 0.5 sec to create the content
    public bool isTouching = false;
    

    public delegate void ContentVisibleDelegate(); 
    public event ContentVisibleDelegate _contentVisibleEvent;

    private void Awake()
    {
        _arRaycastManager = GetComponent<ARRaycastManager>();
    }

    public bool TryGetTouchPosition(out Vector2 touchPosition)
    {
        if (Input.touchCount > 0)
        {
            isTouching = true;
            touchPosition = Input.GetTouch(index: 0).position;
            return true;
        }
        touchPosition = default;
        isTouching = false;
        timeThreshold = 0;
        return false;
    }
/*
  void Update()
    {
       [...]     
    }
*/
public void spawnObject()
{
    if (!TryGetTouchPosition(out Vector2 touchPosition))
        return;

    if (_arRaycastManager.Raycast(touchPosition, hits, trackableTypes: TrackableType.PlaneWithinPolygon))
    {
    var hitPose = hits[0].pose;
        if (spawnedObject == null)
           {
            spawnedObject = Instantiate(gameObjectToInstantiate, hitPose.position, hitPose.rotation);
            _contentVisibleEvent();
        }
        else
        {
            spawnedObject.transform.position = hitPose.position;
        }
    }
}
}

Exit from the Prefab editing mode and select the LeanTouch GameObject, in the Inspector Panel:

We will now have two Lean Finger Tap, one with the double tap to create the object, and one with a single tap used to select the object.

Change also the text in the script uxAR to Double Tap to Place

You should now be able to:

Designing dashboards and charts in Unity can be very challenging without dedicated add-ons. XCharts is a community plugin that takes away the most complex coding part leaving the user a flexible tool to design and customise different chart types with ease. Most of the charts are part of the package delivered with an MIT licence.

Download and install the Unity XCharts 3.8.0 package

The chart can be added directly to the UI, as part of the Screen Space or as a 3D object in the World Space.

To add the chart next to the gauge, open the Prefab and in the Prefab editor right click in the Hierarchy panel and create a UI -> Canvas, right click on it and create a XCharts -> Line Chart.

As XCharts is based on the uGUI system, it will create a new Canvas GameObject as a parent of the selected chart. However, if a Canvas already exists, like the one used for the UI system, it will create the chart inside that one.
By default, the Canvas GameObject is set to Screen Space. select the Canvas GameObject and in the Inspector panel change the Canvas -> Render Mode to World Space.

At this point it is possible to change the scale and position of the Canvas GameObject, e.g.:

The style of the chart is entirely customisable from the Inspector panel, after selecting the Line Chart GameObject from the Hierarchy Panel.

Select the Anchor Presetscenter - middle

The following is just an example of the style that can be set:

Chart

Chart manager

To dynamically change the data of the chart, we can use the same mqttController used to control the pointer of the gauge (it is of course possible to create a new script) with some minor changes:

using UnityEngine;
using XCharts.Runtime;

[More Code]

public float adjustedStart = 0f; // negative values CCW; positive value CW
[Space]
public mqttManager _eventSender;

[Space]
public LineChart lineChart;
int count = 0; //simple counter for the data 

[More Code]

private void OnMessageArrivedHandler(mqttObj mqttObject) //the mqttObj is defined in the mqttManager.cs
{
//We need to check the topic of the message to know where to use it 
if (mqttObject.topic.Contains(topicSubscribed))
{
    pointerValue = float.Parse(mqttObject.msg);

    Debug.Log("Event Fired. The message, from Object " + nameController + " is = " + pointerValue);

    lineChart.AddData(0, count++, pointerValue); // first value refer to the serieIndex, serieName can be used instead
}
}

Save the modified script and fill the field Line Chart in the Inspector with the GameObject Line Chart created above and test the app (remember to set also the Tag of the mqttController to link the mqttManager)

Chart

Chart

In the final part of the workshop we are going to play and control the animation of the gauge. It this example the animation needs to be part of the FBX object imported.

FBX animation Inspector

Empty State

New State

New State

Inspector Multiplier

Conditions animation

The Animator controller is now ready to be connected with a user interface. In this example we are controlling the animation using the Lean Touch asset. Specifically, we want to use a single tap on the object to start the animation (explodeTrigger), and another single tap on the object to play the animation backwards (AnimationSpeed from 1 to -1).

using UnityEngine;
[RequireComponent(typeof(Animator))]
public class animationExplode : MonoBehaviour
{
    Animator animator;
    float speed;
    bool isExploding = false;

    void Start()
    {
        //Get Animator component
        animator = GetComponent<Animator>();
        speed = animator.GetFloat("AnimationSpeed");
    }

The [RequireComponent(typeof(Animator))] ensure that the component Animator is added to the GameObject. The variable speed is used in this case to control the direction of the animation.

public void Explosion()
    {
        if (isExploding == false)
        {
            //Add a Tag value to the animation block, select the animation block from the Animator Controlelr and set its Tag in the Inspector
            if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1"))
            {
                speed = 1;
                animator.SetFloat("AnimationSpeed", speed);
                isExploding = true;
            }
            else
            {
                animator.SetTrigger("explodeTrigger");
                isExploding = true;
            }

        }

        else
        {
            if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1"))
            {
                speed = -1;
                animator.SetFloat("AnimationSpeed", speed);
                isExploding = false;
            }
            else
            {
                speed = -1;
                animator.SetFloat("AnimationSpeed", speed);
                animator.SetTrigger("explodeTrigger");
                isExploding = false;
            }

        }
    }

The Explosion function is used to control the animation and it will be trigger when the ARObject is selected using a Lean Finger Tap.

    
    void Update()
    {

        if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1") && animator.GetCurrentAnimatorStateInfo(0).normalizedTime > 1)
        {
            animator.Play("Scene", -1, 1);
        }
        else if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1") && animator.GetCurrentAnimatorStateInfo(0).normalizedTime < 0)
        {
            animator.Play("Scene", -1, 0);
        }

        //Play animation on key press
        if (Input.GetKeyDown(KeyCode.Q))
        {
            //Add a Tag value to the animation block, select the animation block from the Animator Controlelr and set its Tag in the Inspector
            if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1"))
            {
                speed = 1;
                animator.SetFloat("AnimationSpeed", speed);
            }
            else { animator.SetTrigger("explodeTrigger"); }
        }
        //Reverse animation on key press
        if (Input.GetKeyDown(KeyCode.W))
        {
            if (animator.GetCurrentAnimatorStateInfo(0).IsTag("1"))
            {
                speed = -1;
                animator.SetFloat("AnimationSpeed", speed);
            }
            else
            {
                speed = -1;
                animator.SetFloat("AnimationSpeed", speed);
                animator.SetTrigger("explodeTrigger");
            }
        }

    }
}

The Update function contains a conditional function to control when the animation is finished (to reset its Time to 0 or 1), and the same animation controller of the Explosion function, but triggered using the key Q and W.

You can now Build and Run your project to place the digital gauge in your environment.