C Specification

The xrGetFacialExpressionBlendShapePropertiesML function is defined as:

// Provided by XR_ML_facial_expression
XrResult xrGetFacialExpressionBlendShapePropertiesML(
    XrFacialExpressionClientML                  facialExpressionClient,
    const XrFacialExpressionBlendShapeGetInfoML* blendShapeGetInfo,
    uint32_t                                    blendShapeCount,
    XrFacialExpressionBlendShapePropertiesML*   blendShapes);

Parameters

Parameter Descriptions

Description

XrFacialExpressionBlendShapePropertiesML is better thought of as a mutable state rather than an immutable property. In general, OpenXR convention tries to keep property data types to be immutable.

The xrGetFacialExpressionBlendShapePropertiesML function returns the XrFacialExpressionBlendShapePropertiesML of each blend shape requested in XrFacialExpressionClientCreateInfoML

Each XrFacialExpressionBlendShapePropertiesML in blendShapes must have its requestedFacialBlendShape member variable initialized before being passed into xrGetFacialExpressionBlendShapePropertiesML.

If a blend shape in blendShapes is not enabled in xrCreateFacialExpressionClientML, the runtime must return XR_ERROR_VALIDATION_FAILURE.

For unsupported blend shapes, the runtime must clear XrFacialExpressionBlendShapePropertiesML::flags and the runtime must also return XR_SUCCESS.

Valid Usage (Implicit)
Return Codes
On success, this command returns

  • XR_SUCCESS

  • XR_SESSION_LOSS_PENDING

On failure, this command returns

  • XR_ERROR_FUNCTION_UNSUPPORTED

  • XR_ERROR_VALIDATION_FAILURE

  • XR_ERROR_RUNTIME_FAILURE

  • XR_ERROR_HANDLE_INVALID

  • XR_ERROR_INSTANCE_LOST

  • XR_ERROR_SESSION_LOST

  • XR_ERROR_TIME_INVALID

See Also

XR_ML_facial_expression, XrFacialExpressionBlendShapeGetInfoML, XrFacialExpressionBlendShapePropertiesML, XrFacialExpressionClientCreateInfoML, XrFacialExpressionClientML

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 2014-2025 The Khronos Group Inc.

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