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Hello everyone!
Was trying out the Hololens 2 integration with Unreal Engine 4.26.2 and 4.27.2 using the Microsoft OpenXR github plugin.
Came across this error that I wasn't able to get past:
StartSession cannot be started yet because spatial perception access cannot be verified.
I have a working demo in Unreal using ARKit. It connects to Azure and is able to create and locate spatial anchors.
Any help would be greatly appreciated! Thanks!
I modified the MicrosoftOpenXR plugin's AzureSpatialAncorsForOpenXR module to bypass the check that was throwing the error.
//if (spatialPerceptionAccessStatus != winrt::Windows::Perception::Spatial::SpatialPerceptionAccessStatus::Allowed)
//{
// UE_LOG(LogHMD, Log, TEXT("FAzureSpatialAnchorsForOpenXR::CreateWatcher cannot be started yet because spatial perception access cannot be verified."));
// return EAzureSpatialAnchorsResult::NotStarted;
//}
This allowed the code to progress but sadly it was not able to get spatial data due to the previous error.
LogHMD: CloudSession LogDebug: Failed to get SpatialLocator. Device may have lost tracking..
I have my laptop and Hololens 2 paired using the Developer settings located in the Update / Security menu. The tracking / remote display is working perfectly fine. Let me know if there's anything else to try. Thank you!
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Are you using remoting?
Azure Spatial Anchors does not currently support remoting when using OpenXR.
Please try packaging the app for HoloLens and running it on your device.
Yes, we are using the holographic remoting app on the hololens 2.
Looking at the change log for the app, it appears to support spatial anchors.
https://learn.microsoft.com/en-us/windows/mixed-reality/develop/native/holographic-remoting-version-history#version-270-september-29-2021-
I see on this commit, 256cf338a7169eed9269f31eb3c6abcbecea962c, that you fixed removing spatial anchors.
Is this just getting the pathway clear to add support with the OpenXR Unreal plugin?
Will this be a feature in the near future?
Thanks!
Holographic remoting does support OpenXR anchors, but does not support the legacy anchors that the WMR plugin previously used.
The issue is that the Azure Spatial Anchor API uses those legacy anchors:
https://github.com/microsoft/Microsoft-OpenXR-Unreal/blob/95ea1c6b930ad38e53ed047579224a603005e520/MsftOpenXRGame/Plugins/MicrosoftOpenXR/Source/AzureSpatialAnchorsForOpenXR/Private/AzureSpatialAnchorsForOpenXR.cpp#L1221
I see. That's unfortunate.
Appreciate you answering my questions. It has been super helpful!
Good morning! I wanted to provide a bit more context about our use case.
We're currently developing a tool, called Chimera, that allows for film art departments to visualize their work digitally in real world spaces and scale.
With the Hololens 2 having limited graphics ability, we were hoping to stream content from a desktop while using the other features of the Hololens, like meshing and spatial anchors, through the holographic remote app. Using the streamed unreal editor also allows us to make changes during work sessions while the devices are on the creatives. This is the reason why we're not able to publish the application to device.
We're doing a panel for SXSW called "Visualization in Action: The Future of Ent. Design". (https://schedule.sxsw.com/2022/events/PP118048) If you or anyone on your team happen to be there, we would love to sync up in person and give a demonstration.
Hope that helps in understanding what we're attempting to do. Thanks!
If you use local anchors (ARPins), those use OpenXR anchors which will work over remoting.
However, please change this value to "2.7.4" to enable saving/loading anchors over remoting. The current remoting version Unreal is using only supports creating anchors.
Regenerate project files after making this change.
(I will be making this change soon for our next marketplace update - the main branch currently has this change in it)
Anchors cannot be shared over OpenXR except through Azure Spatial Anchors unfortunately. If you are making a multi-user experience, you could use QR code tracking over remoting to all agree on a shared origin.
Legacy is probably a poor choice of wording - perception anchors and Azure Spatial Anchors will continue to be supported.