How to Set up AR Foundation and ARKit in Unity DOTS

Unity's AR Foundation is an API that sits on top of all the hardware AR SDKs. When we ask for "pose" from AR Foundation, AR Foundation automatically translates that request to whatever appropriate implementation. Unity does not implement any of these functionalities itself, it just a translation layer. AR Foundation calls a platform-specific "plug-in" to get the necessary data from the hardware. So adding the "AR Foundation" package is not enough, we must also include specific packages for AR platforms we will be targeting. In our case it will be ARKit. It is important to note that not all AR Foundation functionalities are available for all plug-ins. For example, ARKit and ARCore both now provide access to a depth API. The HoloLens does not provide this data.

Unity has a robust XR plugin framework. Unity has been working to improve their multi-platform offering, enabling direct integrations through a unified plugin framework. The resulting tech stack consists of an API that exposes common functionalities across their supported platforms in a frictionless way for creators while enabling XR hardware and software providers to develop their own Unity plugins. This architecture offers the following benefits: Multi-platform developer tools such as AR Foundation and the XR Interaction Toolkit Faster partner updates from supported plugins via the Unity Package Manager More platforms have access to an interface to leverage Unity’s XR rendering optimizations and developer tools [Source: Unity]

In MainScene we will run a check if we are an AR system. If we are an AR system, we will create an IsARPlayerComponent singleton. We will then use RequireSingletonForUpdate<IsARPlayerComponent> for our AR-specific systems. We will create a new InputSystem for AR, ARInputSystem, that takes in screen taps and translates them to "shoot" commands. We will also update our PlayerCommand to take in AR pose. So our ARInputSystem will be sending "shoot" data through screen taps and updated position through grabbing ARKit's provided "pose". AR Foundation is written using MonoBehaviours. So we will create and update an ARPlayerPoseComponent in an Update(). The MonoBehaviour will use the EntityManager to update our ARPlayerPoseComponent and our ARInputSystem will pull this data to add it to our PlayerCommand.