Class XRSessionSubsystem

This subsystem controls the lifecycle of an XR session. Some platforms, particularly those that have non-XR modes, need to be able to turn the session on and off to enter and exit XR mode(s) of operation.

Inheritance
Object
Subsystem
Subsystem<XRSessionSubsystemDescriptor>
XRSubsystem<XRSessionSubsystemDescriptor>
XRSessionSubsystem
XRSessionSubsystemImpl
Inherited Members
Namespace: UnityEngine.XR.ARSubsystems
Syntax
public abstract class XRSessionSubsystem : XRSubsystem<XRSessionSubsystemDescriptor>, ISubsystem

Constructors

XRSessionSubsystem()

Do not call this directly. Call create on a valid XRSessionSubsystemDescriptor instead.

Declaration
public XRSessionSubsystem()

Properties

frameRate

The native update rate of the AR Session.

Declaration
public int frameRate { get; }
Property Value
Type Description
Int32
Exceptions
Type Condition
NotSupportedException

Thrown if supportsMatchFrameRate is False.

matchFrameRate

Whether the AR session update is synchronized with the Unity frame rate. If true, Update(XRSessionUpdateParams) should block until the next AR frame is available.

Declaration
public bool matchFrameRate { get; set; }
Property Value
Type Description
Boolean
Exceptions
Type Condition
NotSupportedException

Thrown if supportsMatchFrameRate is False.

nativePtr

Returns an implementation-defined pointer associated with the session.

Declaration
public IntPtr nativePtr { get; }
Property Value
Type Description
IntPtr

notTrackingReason

Gets the NotTrackingReason for the session.

Declaration
public NotTrackingReason notTrackingReason { get; }
Property Value
Type Description
NotTrackingReason

sessionId

Returns a unique session identifier for this session.

Declaration
public Guid sessionId { get; }
Property Value
Type Description
Guid

trackingState

Gets the TrackingState for the session.

Declaration
public TrackingState trackingState { get; }
Property Value
Type Description
TrackingState

Methods

CreateProvider()

Implement this to provide this class with an interface to platform specific implementations.

Declaration
protected abstract XRSessionSubsystem.Provider CreateProvider()
Returns
Type Description
XRSessionSubsystem.Provider

An implementation specific provider.

GetAvailabilityAsync()

Asynchronously retrieves the SessionAvailability. Used to determine whether the current device supports XR and if the necessary software is installed.

Declaration
public Promise<SessionAvailability> GetAvailabilityAsync()
Returns
Type Description
Promise<SessionAvailability>

A Promise<T> which can be used to determine when the availability has been determined and retrieve the result.
Remarks

This platform-agnostic method is typically implemented by a platform-specific package.

InstallAsync()

Asynchronously attempts to install XR software on the current device. Throws if supportsInstall is false.

Declaration
public Promise<SessionInstallationStatus> InstallAsync()
Returns
Type Description
Promise<SessionInstallationStatus>

A Promise<T> which can be used to determine when the installation completes and retrieve the result.
Remarks

This platform-agnostic method is typically implemented by a platform-specific package.

OnApplicationPause()

Should be invoked when the application is paused.

Declaration
public void OnApplicationPause()

OnApplicationResume()

Should be invoked when the application is resumed.

Declaration
public void OnApplicationResume()

OnDestroyed()

Destroys the session.

Declaration
protected override sealed void OnDestroyed()
Overrides
UnityEngine.XR.ARSubsystems.XRSubsystem<UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor>.OnDestroyed()

OnStart()

Starts or resumes the session.

Declaration
protected override sealed void OnStart()
Overrides
UnityEngine.XR.ARSubsystems.XRSubsystem<UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor>.OnStart()

OnStop()

Pauses the session.

Declaration
protected override sealed void OnStop()
Overrides
UnityEngine.XR.ARSubsystems.XRSubsystem<UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor>.OnStop()

Reset()

Restarts a session. and pause and resume a session, respectively. Restart resets the session state and clears and any detected trackables.

Declaration
public void Reset()

Update(XRSessionUpdateParams)

Trigger the session's update loop.

Declaration
public void Update(XRSessionUpdateParams updateParams)
Parameters
Type Name Description
XRSessionUpdateParams updateParams

Data needed by the session to perform its update.