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 modes of operation.

Inheritance

Object

SubsystemWithProvider

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<XRSessionSubsystem, XRSessionSubsystemDescriptor, XRSessionSubsystem.Provider>

XRSessionSubsystem

SimulationSessionSubsystem

Inherited Members

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.OnCreate()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.OnStart()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.OnStop()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.OnDestroy()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.subsystemDescriptor

UnityEngine.SubsystemsImplementation.SubsystemWithProvider<UnityEngine.XR.ARSubsystems.XRSessionSubsystem, UnityEngine.XR.ARSubsystems.XRSessionSubsystemDescriptor, UnityEngine.XR.ARSubsystems.XRSessionSubsystem.Provider>.provider

SubsystemWithProvider.Start()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider.OnStart()

SubsystemWithProvider.Stop()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider.OnStop()

SubsystemWithProvider.Destroy()

UnityEngine.SubsystemsImplementation.SubsystemWithProvider.OnDestroy()

SubsystemWithProvider.running

Object.ToString()

Object.Equals(Object)

Object.Equals(Object, Object)

Object.ReferenceEquals(Object, Object)

Object.GetHashCode()

Object.GetType()

Object.MemberwiseClone()

Namespace: UnityEngine.XR.ARSubsystems

Syntax

public class XRSessionSubsystem : SubsystemWithProvider<XRSessionSubsystem, XRSessionSubsystemDescriptor, XRSessionSubsystem.Provider>, ISubsystem

Constructors

XRSessionSubsystem()

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

Declaration

public XRSessionSubsystem()

Properties

configurationChooser

Get or set the ConfigurationChooser used by DetermineConfiguration(Feature). If set to null, the DefaultConfigurationChooser is used.

Declaration

public ConfigurationChooser configurationChooser { get; set; }

Property Value

Type	Description
ConfigurationChooser

currentConfiguration

The current Configuration in use by the session.

Declaration

public Configuration? currentConfiguration { get; }

Property Value

Type	Description
Nullable<Configuration>

See Also

DetermineConfiguration(Feature)

Feature

currentTrackingMode

Get the current tracking mode in use by the subsystem.

Declaration

public Feature currentTrackingMode { get; }

Property Value

Type	Description
Feature

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.

matchFrameRateEnabled

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 matchFrameRateEnabled { get; }

Property Value

Type	Description
Boolean

Exceptions

Type	Condition
NotSupportedException	Thrown if supportsMatchFrameRate is False.

matchFrameRateRequested

Get or set whether the match frame rate feature should be enabled. When enabled, the AR session update is synchronized with the Unity frame rate.

Declaration

public bool matchFrameRateRequested { get; set; }

Property Value

Type	Description
Boolean

See Also

matchFrameRateEnabled

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

requestedFeatures

Get the requested Features. These are used to determine the session's Configuration.

Declaration

public Feature requestedFeatures { get; }

Property Value

Type	Description
Feature

See Also

DetermineConfiguration(Feature)

requestedTrackingMode

The requested tracking mode. Query for support with SubsystemDescriptor.supportedTrackingModes.

Declaration

public Feature requestedTrackingMode { get; set; }

Property Value

Type	Description
Feature

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

DetermineConfiguration(Feature)

Determines the Configuration the session will use given the requested features.

Declaration

public Configuration? DetermineConfiguration(Feature features)

Parameters

Type	Name	Description
Feature	features	A set of requested Features.

Returns

Type	Description
Nullable<Configuration>	The Configuration the session would use given the requested features, or null if configuration introspection is not available.

Remarks

This method uses the current configurationChooser to choose a configuration using the requested features and the capabilities of the available configurations. The configuration chooser is customizable, see ConfigurationChooser. If you do not set a configuration chooser, the DefaultConfigurationChooser is used.

You can use this method to determine what would happen if you were to enable or disable a particular feature. For example, you can use this method to determine which features would be enabled if you were to change the camera mode from WorldFacingCamera to UserFacingCamera.

See Also

Configuration

ConfigurationChooser

ConfigurationDescriptor

Feature

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 to retrieve the result.

Remarks

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

GetConfigurationDescriptors(Allocator)

Get the list of supported configuration descriptors. The session can have multiple, discrete modes of operation. A configuration represents the capabilities of a mode of operation, which can be a subset of the session's overal capabilities. That is, the session might support many features, but not all at the same time. This is used by DetermineConfiguration(Feature) to determine the best configuration given a set of requested features.

Declaration

public NativeArray<ConfigurationDescriptor> GetConfigurationDescriptors(Allocator allocator)

Parameters

Type	Name	Description
Allocator	allocator	The allocator to use for the returned NativeArray.

Returns

Type	Description
NativeArray<ConfigurationDescriptor>	Allocates a new NativeArray and populates it with descriptors describing the supported configurations. The caller owns the memory and is responsible for calling Dispose on the NativeArray.

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 to 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()

Reset()

Restarts a session. Stop and Start 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.