Bugs with DemoNetDriver and HMD with Stereo Enabled


I am seeing some very strange behavior here when trying to use demonetdriver with an hmd.

Its hard to explain, so please bear with me, there is also nothing being printed into the logs with LogDemo set to VeryVerbose, nothing apart from it starting to play the demo, and it immediately stopping on the first frame.

What im doing:
Playing back a demo

with no HMD:
plays as normal

with HMD:
loads the level, character looks like it doesnt spawn the pawn / controller

starting the project, without HMD on, loading the demo, THEN running “Stereo On” from the console,
works with the HMD! (thats the weird bit)

Im really not sure how to go forward from here as there is nothing usefull being logged about whats happening, but it looks as though it is not spawning the ReplaySpectatorPlayerControllerClass if i try and play a demo when the HMD is already on.

I really want to provide demo playback on my vr game, please help! :slight_smile:


I know this is an old post, but I wanted to link these for visibility:

I’m not sure if your issue is HMD specific, but the behavior is similar to the problems mentioned in the links above. I hope that you’ve resolved your issue by now, but if not, it may help to post some logs.

(edited :wink:
Thanks for pointing that out…

Hi gozu, not sure if your original reply got edited out (saw it in email, but can’t see it on answerhub), but I’m sorry you couldn’t resolve your issue then. It’s distressing to see that the same issue has likely been around for more than a year (and likely longer, probably since the demo replays feature was added). I just wanted to add this answer here in the first place because I had the same issue and couldn’t tell if it was an Unreal problem or my problem. Your question shows up high on searches so I wanted people to be able to find the same links that I did.

That was me, i had replied before having my morning coffee, haha!

I never did fix my issue, but stopped updating the engine on that project at 4.16…
Reading the fix i think it’s actually a differnt issue. But perhaps mine does stem from the same bug. The results are very similar.
Unfortunately i’ll never know as the fix is a bit too late for me.