UE 5.8.0 - blank + openXR plugin + instanced stereo = instant crash in VR

General Issues and Bug Reporting (Unreal Engine)
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1

Summary

instant crash when running instanced stereo + on blank (lumen) project

What Type of Bug are you experiencing?

Platform Other

Steps to Reproduce

  1. create blank project
  2. enable openXR
  3. add some content + vrPawn
  4. play on desktop = ok
  5. play in VR = instant crash

Edit:
OR

  1. create a new VRtemplate project, disable forward shading + restart
  2. change light mobility to moveable
  3. start in VR = instant crash

Expected Result

good + faster working VR

Observed Result

crash

Affects Versions

5.8

Platform(s)

Windows

For crash reports, include your callstack

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000090

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Instanced Stereo + deferred rendering broken in 5.8
2

Hey Max! Which CL of 5.8 release branch are you on? I’m not able to reproduce this with our latest changes that are coming in the hotfix.

3

@VictorLerp Hi VIctor, Just checked, I’m still on 5.8.0 from the launcher.
Just edited the topic title from 5.8.1 to 5.8.0. Nice to hear it is fixed in the coming hotfix

1 Like
4

Just tested 5.8.1 Instanced stereo works now with TSR and Lumen + openXR.
Did save only a few ms.
I did notice in one project reflection glitches in one eye. WIll have to investigate more…

5

The reflection issue is known, we’ve fixed it here (UE5 Main) but unfortunately can’t be included in a hotfix as it invalidates shaders.

1 Like
6

So the fix will be in 5.9 OR 6.0? I prefer not to use a github build because I want to be able to open the project in an official UE version.

7

The release branch on GitHub mirrors the latest official release in the launcher. You can cherry pick the fix into that branch, and continue to be able to open the project in the latest binary version from the launcher

8

Hi Victor,
The same fix should apply to HairStrandsEnvironmentLighting.usf and SingleLayerWaterComposite.usf
Thanks for the fix