Spatial Anchor on Unreal - Samples and how to do it

[dario.maciel]

I managed to install the sample. I took a look at it. I understand the idea but no matter what I tried, i cant start a project and develop spatial anchor from start.

I would like to start a simple project from zero to understand it better.
I have an actor with grab component (from vr template) and would like to create a spatial anchor on it. This way, a person would grab it and move it around. After he left the object it would be saved and someone else could get the actor from the place it was left in another session....

Any idea how to implement a simple spatial anchor? No menus, hover material etc (the sample I thought to be a little complex to understand the principles)

[Shenksu]

Hi 🙂 Iam digging into spatial anchors for hours now. I also found this where you suggest to use spatial anchors: https://communityforums.atmeta.com/t5/Unreal-VR-Development/Room-scale-matching-IRL-location-How-to-...

Now i tried a bunch of things in ue5.3 to set it up. its pretty well explained: https://learn.microsoft.com/en-us/windows/mixed-reality/develop/unreal/unreal-spatial-anchors?tabs=4...

(also started an ar session with arsessionconfig). But when i try to store a pin in the arpin storage, it always returns false (storing failed). When calling "is arpin local store supported" i receive "false" as well. 

Iam actually using a quest 3 in unreal engine 5.3. iam NOT packaging an arp but run the quest 3 VR project in unreal editor using SteamVR and Steam link. Could this potentially the issue?

I wonder why it is so hard in unreal VR to orient in a physical room. Since the head is aware of the room and also of the exact guardian-transformation in the physical room (or champerone in steam), it should also be able to orient in absolute room space somehow. But i dont find a way to do so(like many others). Can only "reorient" in unreal but thats it. Its weird. What are your thoughts about it? 

Thanks mate 🙂

[dario.maciel]

dont use the microsoft page. that is for their hardware (hololens I think)
Use this page instead
https://developer.oculus.com/documentation/unreal/unreal-spatial-anchors/

[Shenksu]

Thank you for your answer :). This requires access to the dedicated oculus framework i guess?! Iam actually on a different way: I try to access the points of the chaperone/guardian playarea. I read couple of things about it. People wrote there is a "Steam VRChaperone"-component that can be added a player pawn or a "Get Guardian Points"-node (oculus) to retrieve points which define the playarea. This also sounds reasonable to me i highly assume these points will always match real world positions, which would be perfect to interlock virtual objects in the given playarea.

But i dont find the named component nor the the named oculus node. I guess it requires some steam/oculus propreitary plugins that provide these component/nodes. Since ue only ships with openxr, there is no steam/oculus related component/node but only stuff for the generalized openxr stuff.

So maybe you have some insight about how to fetch chaperone/guardian data from openxr ?

[dario.maciel]

i dont think you can access the points on the guardian (i dont know how and even if its possible). you can access the boundaries of it. but to make virtual objects at specific phisical place just use the spatial anchor.

As far as I know, you need to use all the nodes from oculus (now MetaXR with you are using unreal 5). The only node from OpenXR that works with oculus are the Get Eye Gaze (something like that) to do eye tracking with meta quest pro.

The steam node you talked about could work with you are developing a PC/Steam aplication and just use the meta quest as a display device (using air link, for example). But I never used steam vr or anything, so good luck

[Shenksu]

I got it to work finally. Ill sum it up real quick for others cause it was a bigger hustle for me, specially for those who are new:

1. I installed the metaxr plugin from the meta website for ue5.3.2 (can also be done via epic marketplace, search for "metaxr"). Maybe follow short install instructions on meta page: https://developer.oculus.com/downloads/package/unreal-engine-5-integration/60.0

2. Setup developer account at meta and bring the quest 3 into developer mode afterwards (like people do when sideloading stuff over adb)

3. Log out from oculus software on pc and re-login (needed to do it to make it recognize that iam a dev now)

4. Within the occulus software on pc: Switch "OpenXR-Runtime" to use the Oculus runtime

4. Also in occulus software: Go to "Preferences" -> "Beta" -> Switch on "Runtime Features for Devs". I checked "Passthrough via Oculus Link" and "Pointcloud via occulus link" (dunno how the english terms are. I use german language in app) - options will only appear once the software recognizes that you are dev. This is why i re-logged in.

5. In unreal i disabled openxr, restarted and enabled metaxr

6. In unreal under "Project settings" under "Plugins" open "Meta XR" i enabled "Anchor Support" and "Anchor Sharing"

After that i just followed the instructions on https://developer.oculus.com/documentation/unreal/unreal-spatial-anchors/
as you mentioned and works like a charm - also when running the VR project in UE Editor with Quest 3 being connected via Air Link ... So no need to build APK yay! 🙂

Thanks for helping me with this :))

[theodorriedltimeride]

Hi @Shenksu . I managed to complete alle stept 1-6 but cant get the actual anchor to work. Could you go into more detail what you exactly did by saying "After that i just followed the instructions on https://developer.oculus.com/documentation/unreal/unreal-spatial-anchors/".

I found the sample project but i cant implement it in my own project.

Thank you very much 🙂