[4.8] VR Preview mode often does not open in stereo, engine restart required

If I want VR Preview mode to work, it generally has to be first way that I play a map. If I play “standard” way ( first option in drop-down) on selected viewport first, then on subsequent tries if I choose VR Preview mode it will minimize engine and open up a new viewport but it will not be in stereo. Then, trying console commands such as “hmd stereo on” or “stereo on” do nothing. Exiting and trying again never works, and I have to close editor to get it to work again.

Hi James,

Thanks for your report. We have assigned this issue to a member of our support staff, and they will begin investigation as soon as possible. If we are unable to reproduce issue, or we need additional information, our staff member will comment here with additional questions. Otherwise, we will post an ‘Answer’ once we have logged issue in our bug database or we have a solution for it.

In meantime, please be sure to review our suggestions for how to report a bug, and feel free to edit your post if you have additional information to provide:

Thanks!

Hello ,

This issue sounds very similar to one that has already been reported. I have a few questions that will help narrow down what issue it is that you are experiencing.

Quick questions:

  1. Can you reproduce this issue in a clean project?
  2. If so, could you provide set of steps to reproduce this issue on our end?
  3. Was project that is having this issue upgraded from an older version of engine?
  4. If you close all of tabs that are open in editor (other than main tab) and launch VR preview, does this issue still occur?

I also am having this issue in my project. I am using a DK2, Unreal Engine v4.8.2, I could not reproduce issue in a new project using first person starter content. I notice it happens if I do anything in my pawn character blueprint.

Hello Arkayar,

Could you provide answers to questions number 3 and 4? These two questions will help determine if this is a known issue.

  1. On a clean project, I cannot reproduce this issue. I am able to start VR preview correctly, exit, play in viewport, exit, and open VR preview correctly again. It seems I can’t break it.

  2. Seems to be fine on a clean project! (I tried a clean First Person blueprint project).

  3. project I’m having an issue with has been upgraded through first official release of UE4.0.

  4. Wow, I think you’ve solved issue. If I make sure all other tabs are closed, I don’t believe I can reproduce issue. Still, it would be nice to have my Blueprints open that I’m iterating on while I do VR development, however thank you for clarifying and providing a working solution.

You may be able to go back into VR Preview mode after closing down that Blueprint. I just discovered this works on our end. Sort of an annoyance to have to close Blueprints for every VR test, but at least it’s not same as closing editor down each time.

Hello James ,

Thank you for additional information. This is a known issue and it has been integrated into main (4.9). I have provided a link to commit below. You can follow link provided if you are working from source and would like to integrate this solution into your project. I hope that this information helps.

Commit:

https://github.com/Crtriplett/UnrealEngine/commit/c6899b95de6c75f992249cefc97650c104621d57

Make it a great day

  1. Yes my project started on UE4 4.7.x, and currently running on latest 4.8.2

  2. I just tried this, and it works!! If I close all my tabs, It launches into VR preview as expected! Thanks, I’m a little embarrassed I didn’t think to try that. I agree that its a bit annoying that I cant leave my BP open while testing, however this workaround is WAY better than restarting UE4. I originally thought it would happen anytime i did anything in BP, Now I realize it was because I was leaving that BP open. Thanks again.