Systems, extension services, and data providers — MRTK2

In Mixed Reality Toolkit, many of the features are delivered in the form of services. Services are grouped into three primary categories: systems, extension services and data providers.

Systems

Systems are services that provide the core functionality of Mixed Reality Toolkit. All systems are implementations of the IMixedRealityService interface.

• BoundarySystem
• CameraSystem
• DiagnosticsSystem
• InputSystem
• SceneSystem
• SpatialAwarenessSystem
• TeleportSystem

Each of the listed systems are surfaced in the MixedRealityToolkit component's configuration profile.

Extensions

Extension services are components that extend the functionality of Mixed Reality Toolkit. All extension services must specify that they implement the IMixedRealityExtensionService interface.

For information on creating extension services, please reference the Extension services article.

To be accessible to the MRTK, extension services are registered and configured using the Extensions section of the MixedRealityToolkit component's configuration profile.

Data providers

Data providers are components that, per their name, provide data to a Mixed Reality Toolkit service. All data providers must specify that they implement the IMixedRealityDataProvider interface.

To be accessible to the specific MRTK service, data providers are registered in the service's configuration profile.

Application code accesses data providers via the IMixedRealityDataProviderAccess interface. To simplify access, data providers can also be retrieved via the CoreServices helper class.

var inputSimulationService = CoreServices.GetDataProvider<IInputSimulationService>(CoreServices.InputSystem);

Input

The MRTK input system utilizes only data providers that implement the IMixedRealityInputDeviceManager.

The following example demonstrates accessing the input simulation provider and toggle the SmoothEyeTracking property.

IMixedRealityDataProviderAccess dataProviderAccess = CoreServices.InputSystem as IMixedRealityDataProviderAccess;

if (dataProviderAccess != null)
{
    IInputSimulationService inputSimulation =
        dataProviderAccess.GetDataProvider<IInputSimulationService>();

    if (inputSimulation != null)
    {
        inputSimulation.SmoothEyeTracking = !inputSimulation.SmoothEyeTracking;
    }
}

Accessing a data provider for the core input system can also be simplified via use of the CoreServices helper class.

var inputSimulationService = CoreServices.GetInputSystemDataProvider<IInputSimulationService>();
if (inputSimulationService != null)
{
    // do something here
}

For information on writing a data provider for the MRTK input system, please see creating an input system data provider.

Spatial awareness

The MRTK spatial awareness system utilizes only data providers that implement the IMixedRealitySpatialAwarenessObserver interface.

The following example demonstrates accessing the registered spatial mesh data providers and changing the visibility of the meshes.

IMixedRealityDataProviderAccess dataProviderAccess =
    CoreServices.SpatialAwarenessSystem as IMixedRealityDataProviderAccess;

if (dataProviderAccess != null)
{
    IReadOnlyList<IMixedRealitySpatialAwarenessMeshObserver> observers =
        dataProviderAccess.GetDataProviders<IMixedRealitySpatialAwarenessMeshObserver>();

    foreach (IMixedRealitySpatialAwarenessMeshObserver observer in observers)
    {
        // Set the mesh to use the occlusion material
        observer.DisplayOption = SpatialMeshDisplayOptions.Occlusion;
    }
}

Accessing a data provider for the core spatial awareness system can also be simplified via use of the CoreServices helper class.

var dataProvider = CoreServices.GetSpatialAwarenessSystemDataProvider<IMixedRealitySpatialAwarenessMeshObserver>();
if (dataProvider != null)
{
    // do something here
}

For information on writing a data provider for the MRTK spatial awareness system, please see creating a spatial awareness system data provider.

See also

• Extension services
• Creating an input system data provider
• Creating a spatial awareness system system data provider
• IMixedRealityService interface
• IMixedRealityDataProvider interface
• IMixedRealityExtensionService interface