C Specification

The XrFaceTrackerCreateInfo2FB structure is described as follows:

// Provided by XR_FB_face_tracking2
typedef struct XrFaceTrackerCreateInfo2FB {
    XrStructureType                 type;
    const void*                     next;
    XrFaceExpressionSet2FB          faceExpressionSet;
    uint32_t                        requestedDataSourceCount;
    XrFaceTrackingDataSource2FB*    requestedDataSources;
} XrFaceTrackerCreateInfo2FB;

Members

Member Descriptions

  • type is the XrStructureType of this structure.

  • next is NULL or a pointer to the next structure in a structure chain. No such structures are defined in core OpenXR or this extension.

  • faceExpressionSet is an XrFaceExpressionSet2FB that describes the set of blend shapes to retrieve.

  • requestedDataSourceCount is the number of elements in the requestedDataSources array.

  • requestedDataSources is an array of XrFaceTrackingDataSource2FB that the application accepts. The order of values in the array has no significance.

Description

The XrFaceTrackerCreateInfo2FB structure describes the information to create an XrFaceTracker2FB handle.

Runtimes may support a variety of data sources for estimations of facial expression, and some runtimes and devices may use data from multiple data sources. The application tells the runtime all data sources that the runtime may use to provide facial expressions for the application.

Because the device setting may change during a running session, the runtime may return a valid XrFaceTracker2FB handle even if the device is unable to estimate facial expression using the data sources requested by the application’s call to xrCreateFaceTracker2FB. The runtime must instead return XR_ERROR_FEATURE_UNSUPPORTED from xrCreateFaceTracker2FB, if for example the runtime believes it will never be able to satisfy the request.

If requestedDataSourceCount is 0, the runtime may choose any supported data source, preferably one that is more expressive than the others.

If any value in requestedDataSources is duplicated the runtime must return XR_ERROR_VALIDATION_FAILURE from the call to xrCreateFaceTracker2FB.

Valid Usage (Implicit)

See Also

XR_FB_face_tracking2, XrFaceExpressionSet2FB, XrFaceTrackingDataSource2FB, XrStructureType, xrCreateFaceTracker2FB

Document Notes

For more information, see the OpenXR Specification

This page is extracted from the OpenXR Specification. Fixes and changes should be made to the Specification, not directly.

Copyright

Copyright 2014-2024, The Khronos Group Inc.

This work is licensed under a Creative Commons Attribution 4.0 International License.