[MRTK3] world locked rendering or tracking broken on app resume

[pajama]

This issue has been migrated a new MRTK repository, and the status of this issue will now be tracked at the following location:

• [MRTK3] world locked rendering or tracking broken on app resume MixedRealityToolkit/MixedRealityToolkit-Unity#350

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Describe the bug

App runs fine on fresh launch, but after launching the HL2 home menu then resuming the app, it seems head/space tracking is broken.

To reproduce

1. launch Simple MRTK3 app with a canvas being positioned from a RadialView solver.
   2.Launch the home menu,
2. re enter the app, the canvas will now be fixed to the users view.

Your setup (please complete the following information)

• Unity 2020.3.38f1
• MRTK 3.preview11

Target platform (please complete the following information)

• HoloLens 2

Additional context

I'm using URP
I'm using the default MRTK XR Rig, however I get this warning in my logs
Camera "Main Camera" does not use a AR Pose Driver or a Tracked Pose Driver, so its transform will not be updated by an XR device. In order for this to be updated, please add either an AR Pose Driver or a Tracked Pose Driver.

[pajama]

I was able to fix the issue by

1. enabling Run In Background
2. adding a tracked pose driver to the camera

I'm not sure which of those steps were the solution.

[pajama]

reopening in case this is something that should still be fixed mrtk side

[Zee2]

adding a tracked pose driver to the camera

@pajama By this, do you mean replacing the TrackedPoseDriver (Input System) with the non-Action-based TrackedPoseDriver?

i.e., doing this?

[Zee2]

@pajama Just pinging here again :)

[pajama]

adding a tracked pose driver to the camera

@pajama By this, do you mean replacing the TrackedPoseDriver (Input System) with the non-Action-based TrackedPoseDriver?

i.e., doing this?

I added the non action based one but did not remove the input system version.

[keveleigh]

Interesting...thanks for the confirmation on the Tracked Pose Driver.
Can you please report which version if the Input System package you're using?

[keveleigh]

I was able to fix the issue by

1. enabling Run In Background
2. adding a tracked pose driver to the camera

I'm not sure which of those steps were the solution.

Both of these are actually potential fixes to this issue! Though it should have been fixed by a specific release of the Input System...I think 1.4.0.

[Zee2]

Adding @Clandguth here to repro the errors on app resume.

[AMollis]

@srinjoym can you try to reproduce

[srinjoym]

Unable to reproduce on the MRTK Dev Template project with Unity 2020.3.44 and Input System 1.4.4. Looks like this is fixed now with the input system package