• Let's start by adding our packages to manifest.json
• Paste these two lines into your manifest.json file in the Project folder

• Next we need to enable our Plug-in
• In Unity, navigate to "Project Settings" (Edit > Project Settings) then click XR Plug-in Management
• Click on the iOS tab and check the box next to "ARKit"

• Next we need to provide our app end-users a reason for why we're asking to use their camera (because we need it for ARKit) when we ask for permission during start-up of the app

  • Navigate to "Build Settings" (under "File"), then "Player Settings", and when "Player" is selected on the left panel, click the iOS tab

    • Scroll down to "Camera Usage Description" under "Other Settings" and enter the following text into the text field: "Camera will be used for AR capabilities"
    • Scroll down to "Requires ARKit support" and set it to true

Unity's explanation of ARSession

An AR scene should include an ARSession component. The AR Session controls the lifecycle of an AR experience by enabling or disabling AR on the target platform. The ARSession can be on any GameObject.

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When you disable the ARSession, the system no longer tracks features in its environment, but if you enable it at a later time, the system will attempt to recover and maintain previously-detected features.

If you enable the Attempt Update option, the device tries to install AR software if possible. Support for this feature is platform-dependent.

Note: An AR session is a global construct. An ARSession component manages this global session, so multiple ARSession components will all try to manage the same global session.

Checking for device support

Some platforms might support a limited subset of devices. On these platforms, your application needs to be able to detect support for AR Foundation so it can provide an alternative experience when AR is not supported.

The ARSession component has a static coroutine that you can use to determine whether AR is supported at runtime:

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public class MyComponent {

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[SerializeField] ARSession m_Session;

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IEnumerator Start() {

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if ((ARSession.state == ARSessionState.None) ||

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(ARSession.state == ARSessionState.CheckingAvailability))

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{

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yield return ARSession.CheckAvailability();

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}

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if (ARSession.state == ARSessionState.Unsupported)

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{

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// Start some fallback experience for unsupported devices

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}

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else

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{

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// Start the AR session

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m_Session.enabled = true;

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}

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}

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}

Copied!

Session state

To determine the current state of the session (for example, whether the device is supported, if AR software is being installed, and whether the session is working), use ARSession.state. You can also subscribe to an event when the session state changes: ARSession.stateChanged.

AR Session Origin

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The purpose of the ARSessionOrigin is to transform trackable features, such as planar surfaces and feature points, into their final position, orientation, and scale in the Unity Scene. Because AR devices provide their data in "session space", which is an unscaled space relative to the beginning of the AR session, the ARSessionOrigin performs the appropriate transformation into Unity space.

This concept is similar to the difference between "model" or "local" space and world space when working with other Assets in Unity. For instance, if you import a house Asset from a DCC tool, the door's position is relative to the modeler's origin. This is commonly called "model space" or "local space". When Unity instantiates it, it also has a world space that's relative to Unity's origin.

Likewise, trackables that an AR device produces, such as planes, are provided in "session space", relative to the device's coordinate system. When instantiated in Unity as GameObjects, they also have a world space. In order to instantiate them in the correct place, AR Foundation needs to know where the session origin should be in the Unity scene.

ARSessionOrigin also allows you to scale virtual content and apply an offset to the AR Camera. If you're scaling or offsetting the ARSessionOrigin, then its AR Camera should be a child of the ARSessionOrigin. Because the AR Camera is session-driven, this setup allows the AR Camera and detected trackables to move together.

From AR Foundation's About AR Foundation documentation​

• Back in Unity, navigate to MainScene in your Scenes folder and open up MainScene

  • Right-click on the Hierarchy, select "XR" then AR Session
  • Right-click on the Hierarchy, select "XR" then AR Session Origin

• Now let's create the script that will check for device support

  • If there is no AR support on a particular device attempting to use your app, then the AR Session component and the AR Session Origin GameObject will be disabled
  • Select the "AR Session" GameObject in Hierarchy
  • When AR Session is selected, go to the Inspector and click "Add Component" and create a new script called "ARPlatformInitializer" and click "Create and add"
  • Once created and added, drag the file into the Scripts and Prefabs/Mixed folder
  • Paste the code snippet below into ARPlatformInitializer.cs:

• Now let's create a new component (the component that is referenced in the script above, which is why you might have an error right now in Unity-- the component it references does not exist yet!)
• Create a C# script named "IsARPlayerComponent" in the Client/Components folder
• Paste the code snippet below into IsARPlayerComponent.cs:

• Now select the "AR Session" GameObject in Hierarchy again and drag the ARSession and ARSessionOrigin GameObjects from the Hierarchy into the appropriate fields in the ARPlatformInitializer component in Inspector

• Let's go to NavigationScene, hit play, and host a game to make sure that are GameObjects are indeed disabled (by expanding MainScene in Hierarchy while in playmode)

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• Navigate to BuildSettings, right-click, and select "Create", then, "Build", then, "MacOS Classic Build Configuration" and name it "iOS-Build"

• Select iOS-Build and in the Inspector remove "General Settings" and "Scene List" components (by clicking the three-dot menu and selecting "remove overrides")
• Expand "Shared Configurations" at the top then click "+ Add Configuration"
• Drag "BaseBuildConfiguration" into the field and then hit "Apply"

• Next under the "Classic Scripting Settings" component

  • choose "IL2CPP" as Scripting Backend
  • choose "Debug" as IL2CPP Compiler Configuration
  • under Classic Build Profile, choose "iOS" from the Platform dropdown, hit "Apply", and then at the top of Inspector hit "Build and Run"

    • Sometimes you need to hit "Build and Run" twice as it fails the first time (sometimes even 3 times...)

      • "Editor's active Build Target needed to be switched to iOS..."

• Next, in Xcode, make sure you set up your signing capabilities

  • Click on the "Unity-iPhone" project at on the left
  • Click on "Signing & Capabilities"
  • Make sure you are able to sign the application
• Hit "Play" in XCode to deploy the application

  • you can either connect an iOS device to run your application or choose a simulated device as the destination

• Host a game