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How can I access the Hololens Locatable Camera view and projection matrices with the WinRT API?
The documentation for the Hololens gives an example of how to extract the Locatable Camera view and projection matrices using the Media Foundation API here: https://developer.microsoft.com/en-us/windows/mixed-reality/locatable_camera#locating_the_device_camera_in_the_world.
It claims that this is also possible with the WinRT API, and links to this documentation reference: https://docs.microsoft.com/en-us/uwp/api/Windows.Media.Devices.Core.CameraIntrinsics.
However, this class does not seem to have any API to retrieve the extended Hololens attributes, only the default Windows Phone ones like the distortion matrix and pinhole properties.
Is the Hololens documentation incorrect and is it simply not possible to retrieve the Locatable Camera metadata in the WinRT API? Or am I missing something?
The Spatial Coordinate System (3rd and last extended sample metadata attribute) does seem to be available as MediaFrameReference.CoordinateSystem (https://docs.microsoft.com/en-us/uwp/api/windows.media.capture.frames.mediaframereference), which makes this even more confusing...