Unity Arcore



Unity is the ultimate game development platform. Use Unity to build high-quality 3D and 2D games, deploy them across mobile, desktop, VR/AR, consoles or the Web, and connect with loyal and enthusiastic players and customers. In this tutorial, we will learn to install, build, and deploy Unity ARCore apps for Android. Unity is a leading cross-platform game engine that is exceptionally easy to use for building game and graphic applications quickly. Unity has developed something of a bad reputation in recent years due to its overuse in poor-quality games.

Use the ARCore XR Plugin package to enable ARCore support via Unity's multi-platform XR API. This package implements the following XR Subsystems:

Unity Arcore

This version of ARCore XR Plugin supports only the functionality available as of ARCore 1.19:

  • Device Localization
  • Horizontal Plane Detection
  • Vertical Plane Detection
  • Point Clouds
  • Pass-through Camera View
  • Light Estimation
  • Reference Points
  • Oriented Feature Points
  • Hit Testing
  • Session Management
  • ARCore Apk On-Demand Installation
  • Image tracking
  • Face tracking

It does not support the following subsystems:

To install this package, follow the instructions in the Package Manager documentation.

In addition, you will likely want to also install the AR Foundation package which makes use of ARCore XR Plugin package and provides many useful scripts and prefabs.

For more information on the AR Foundation package, please read the AR Foundation Documentation.

The ARCore XR Plugin implements the native endpoints required for building Handheld AR apps using Unity's multi-platform XR API. However, this package does not expose any public scripting interface of its own and most developers should use the scripts, prefabs, and assets provided by AR Foundation as the basis for their Handheld AR apps.

Inclusion of the ARCore XR Plugin will result in the inclusion of source files, static libraries, shader files, and plugin metadata.

Build Settings

ARCore may be either 'required' or 'optional'. If ARCore is optional, the Play Store will allow your app to be installed on a device that does not support ARCore, or where ARCore may be supported but not installed. This is useful if you want to provide an experience which uses AR where available, and presents a different experience where AR is not available. By default, AR is required. To create an ARCoreSettings asset and assign it to your build settings, click Edit > Project Settings then navigate to XR > ARCore:

Note: If ARCore is 'required', then the availability check will always report that ARCore is supported, even on unsupported devices. This is because the Play Store prevents the installation of ARCore-required apps on unsupported devices, so an ARCore-required app always assumes it is running on a supported device. However, if you install an Android APK onto an unsupported device via USB (called 'side loading') or via Unity, the unsupported device will report that ARCore is supported.

Session

See the ARSubsystems Session documentation. ARCore's implementation of XRSessionSubsystem.GetAvailabilityAsync is somewhat complex. The list of supported ARCore devices is frequently updated to include additional devices, so if ARCore is not already installed on the device, the app needs to check with the Play Store to see if there is a version of ARCore which supports that device. GetAvailabilityAsync returns a Promise which can be used in a coroutine. For ARCore, this check may take some time.

If the device is supported, but ARCore is not installed (or requires an update), then you will need to call XRSessionSubsystem.InstallAsync which again returns a Promise.

Depth Subsystem

See the ARSubsystems Depth Subsystem documentation for more details. Raycasts always return a Pose for the item the raycast hit. When raycasting against feature points, the pose is oriented to provide an estimate for the surface the feature point might represent.

The depth subsystem does not require additional resources, so enabling it does not incur any performance impact.

ARCore's depth subsystem will only ever produce a single XRPointCloud.

Plane Tracking

See the ARSubsystems Plane Subsystem documentation for more details. ARCore supports plane subsumption, i.e., one plane may be subsumed by another. When this happens, the subsumed plane will not be removed, but will also not be updated any further.

ARCore provides boundary points for all its planes.

The ARCore plane subsystem requires additional CPU resources and can be energy intensive. Enabling both horizontal and vertical plane detection requires additional resources. Consider disabling plane detection when not needed to save energy.

Setting the plane detection mode to PlaneDetectionMode.None is equivalent to Stopping subsystem.

Image Tracking

To use image tracking on ARCore, you will first need to create a Reference Image Library. See the AR Subsystems documentation on image tracking for instructions.

When building the Player for Android, each reference image library is used to generate a corresponding imgdb file, ARCore's representation of the reference image library. These files are placed in your project's StreamingAssets folder in a subdirectory called HiddenARCore to allow them to be accessible at runtime.

ARCore's AR Reference Images can be either JPEG or PNG files. If a different type of source texture is specified in the XRReferenceImageLibrary Mac for linux developers. , then the ARCore build processor will attempt to convert the texture to a PNG for ARCore to use. Exporting a Texture2D to PNG can fail for several reasons. For instance, the texture must be marked both readable and uncompressed in the texture importer settings. Note that if you plan to use the texture at runtime (and not just as a source asset for the reference image), you should create a separate PNG or JPEG as the source asset, since those texture import settings can have undesirable performance or memory impacts at runtime.

Unity Arcore Youtube

Reference Image Dimensions

Image dimensions are optional on ARCore; however, specifying them can improve image detection. If you specify the dimensions for a reference image, only the image's width is provided to ARCore. It computes the height from the image's aspect ratio.

Face Tracking

See the ARSubsystems Face Tracking documentation for more details regarding face tracking.

In addition to the core functionality, there are additional methods on the ARCore face subsystem to allow access to ARCore-specific features. ARCore provides access to 'regions', which are specific features on a face. Currently, the features are

  • Nose tip
  • Forehead left
  • Forehead right

Each region has a Pose associated with it. To access face regions, you'll need to obtain an instance of the ARCoreFaceSubsystem:

Arcore Unity Sdk

Requirements

Unity arcore tutorial

This version of ARCore XR Plugin is compatible with the following versions of the Unity Editor:

  • 2019.4.15f1 and later (recommended)

Known limitations

  • The AR Core Supported checkbox in the XR Settings section of the Android Player settings must remain unchecked in order for apps built with the ARCore XR Plugin to work properly.
  • Color Temperature in degrees Kelvin is not presently supported.
  • Due to changes made in Google's ARCore client libraries which are redistributed in ARCore XR Plugin, projects built with Unity 2019.4 must be updated to use Gradle 5.6.4 or later. Please refer to these instructions for updating your project's Gradle version.

Package contents

Unity Arcore

This version of ARCore XR Plugin includes:

  • A shared library which provides implementation of the XR Subsystems listed above
  • A shader used for rendering the camera image
  • A plugin metadata file

Document revision history

Unity Ar Camera

DateReason
April 19, 2018Documentation update.
June 1, 2018Add documentation and screenshots for ARCore build settings. Remove incorrect reference to Xcode and iOS.
June 7, 2018
  • Change reference from Player Settings to Project Settings
  • Change reference from AR Utilities to AR Foundation
June 11, 2018
  • Add link to AR Foundation documentation in Installing ARCore Plugin
  • Changed arcore_settings photo to reflect most recent changes
April 22, 2019Update documentation for 2.1-preview package.