QRCodeSpacePins are not persistent with recent WLT versions

[aleneum]

I recently updated WLT and realized that SpacePins set with QR-Codes stopped being saved/loaded correctly. Whenever I restart
the program running on my HoloLens2, the scene transformation is more or less reset. I could reproduce this behavior with the sample code as written below. I adjusted the scene slightly to only use two markers which I printed on a sheet of paper.
The scene is saved and restored as expected when using the WLT version included in the sample. However, when I update CoreEngine and Tools (as well as the NuGet package dependencies), the scene is either not stored or loaded correctly.

Steps to reproduce

Preparation

• Clone https://github.com/microsoft/MixedReality-WorldLockingTools-Samples.git
• Load Advanced/QRSpacePins with UnityEditor (2019.4.22f1)
• Load Scene Scenes/QRSpacePins
• Remove all markers except QRCode_1 and QRCode_2 from HouseHold/BarnMarkers/Markers
• Reset transform of QRCode_1 and QRCode_2
• Set position of QRCode_1 to {x: -0.0625, y:0, z: 0.2025} and QRCode_2 to {x: -0.0625, y: 0, z: 0.0625}
• Adjust Size of QRSpacePinGroup of MarkerPinsRoot/Barn_MarkerPins
• Enable AutoLoad and AutoSave in WorldLocking/WorldLockingManager

This works

• Build, deploy and run project (on HL2)
• accept all the permission dialogs and restart the program
• look at printout of wlt_markers.pdf
• markers should be detected and scene should be adjusted
• restart program
• scene transformation should be loaded (AnchorGraphVisual '1' hovering above printout)

This does not

• Download WLT 1.32 CoreEngine and Tools
• Drag packages to UnityEditor and import them
• Update NuGet packages FrozenWorld to 1.1.0, VCRTForwarders to 140.1.0.7 and QR to 0.5.2112
• delete previous build folder
• Build, deploy and run project (on HL2)
• accept all the permission dialogs and restart the program
• look at printout of wlt_markers.pdf
• markers should be detected and scene should be adjusted
• restart program

What I expected

• scene transformation should be loaded (AnchorGraphVisual '1' hovering above printout)

What happened instead

• AnchorGraphVisual '1' hovers close to (but not exactly at the same position as) 'SpongySpace' root.

[fast-slow-still]

Thanks for the very detailed bug report. I have been able to reproduce the issue. I've ruled out a couple of things, but haven't found the failure point yet.

I hope to narrow down the problem and fix it tomorrow. I'll update this issue as the situation clarifies.

Thanks again for the detailed writeup, that is extremely helpful!

[fast-slow-still]

I have put the fix in the main WLT repo, along with release 1.3.4.

Also, I have updated the QR Code Sample up to WLT v1.3.4 and MRTK 2.6.1 and QR SDK 0.5.2112.

Please let me know if you are still having issues. Thanks!

[aleneum]

Just FYI, I tested the QRCodeSpacePins example again with the recent release and things work fine 👍

[fast-slow-still]

Fantastic, I appreciate you taking the time to post an update!