C Specification

The xrGetMarkerNumberML function is defined as:

// Provided by XR_ML_marker_understanding
XrResult xrGetMarkerNumberML(
    XrMarkerDetectorML                          markerDetector,
    XrMarkerML                                  marker,
    uint64_t*                                   number);

Parameters

Parameter Descriptions

  • markerDetector is the detector object to retrieve marker information from.

  • marker is the marker atom to be examined.

  • number points to a float in which the numerical value associated with the marker is returned.

Description

Get the numerical value of a marker, such as the ArUco ID. xrGetMarkerNumberML must only be called when the state of the detector is XR_MARKER_DETECTOR_STATUS_READY_ML. If the marker does not have an associated numerical value, the runtime must return XR_ERROR_MARKER_DETECTOR_INVALID_DATA_QUERY_ML.

If xrGetMarkerDetectorStateML has not been called and returned XR_MARKER_DETECTOR_STATUS_READY_ML since the last invocation of xrSnapshotMarkerDetectorML, the runtime must return XR_ERROR_CALL_ORDER_INVALID.

The runtime must return XR_ERROR_MARKER_INVALID_ML if the marker atom is invalid.

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_MARKER_INVALID_ML

  • XR_ERROR_MARKER_DETECTOR_INVALID_DATA_QUERY_ML

See Also

XR_ML_marker_understanding, XrMarkerDetectorML, XrMarkerML, xrGetMarkersML

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.