Hello,
I was trying out the new Volumetric Clouds feature of 4.26 in VR on my Oculus Headset and the portion of my FOV where the clouds are glitch and is distorted. Needless to say this doesn’t happen when I’m not using it in the scene. Wondering of this feature is compatible for VR? If not, is there an alternative? Thanks for your time.
Regards,
Paddy
1 Like
You need to disable instanced stereo rendering, you will take a ~40% base pass performance decrease
Nope, disabling instanced Stereo does not help. The clouds are still blurry and corrupted in the right eye. Tried it with forward and defferred Shading and instance stereo on and off. The feature seems not to be VR-Ready, maybe the forgot to test it xD
So I have to fallback to texture-based sky…
Both of the big features of 4.26 do NOT work in VR… which is disappointing
Volumetric Clouds
Do not animate and only appear static in left eye and glitchy in the other
Water
Only works in left eye
I can confirm that…
Water works in VR with instanced stereo off, but volumetrics don’t work at all even if mono culling disabled also and round robin disabled as well and using default deferred renderer as opposed to forward shading.
I’m curious why is that? How can we enable volumetrics in VR?
would love something official from unreal about this. I submitted a bug but i don’t see it on the issues tracker. Case # 00290173: volumetric clouds not visible in one eye in VR
Without these features enabled, developing for VR causes a massive performance cost on even high end machines and then you also want to be seeing complex rendering features like volumetrics and fluid sim. In addition to the lack of volumetrics (not a problem in 4.25, but still has a huge performance cost) Ive noticed translucent materials simply not appearing in one eye and controls for Reverb G2 being broken (might work with HP’s plugin, but for 4.26 only? Come off it HP).
Just put a pin in 4.26, its broken for VR.
might as well say put a pin in UE for VR if we cannot use new features going forward or keep working in UE with the hope they might be fixed one day.
I after some thought can work around the water, as in landlocked levels. The clouds also not a big deal for flying shooter, same with translucent materials .
You misunderstood me - you only need to disable instanced stereo for water, everything else VR related like Round Robin occlusion works fine with water.
And it doesn’t cause performance hit that’s noticeable assuming you use mono culling distance instead. Which is basically beyond a certain distance rendering everything only for one eye and duplicating it for another instead of rendering separately for each. I did not notice much of performance difference in my scene, even though grass and rocks meshes up close were rendering twice, but distant landscape and distant meshes beyond 7.5 meters only once.
4.25 is perfectly fine for VR, in my experience. My current base VR project is in 4.25 and it works flawlessly, even with my Reverb. 4.26 is basically the “We added a bunch of our Fortnite tools” release, and since theres no VR support for Fortnite I understand if things arent going to work out of the box. It doesnt mean this kind of thing isnt frustrating, but it also doesnt mean Epic has given up on VR.
Expect to see “VR Improvements” as a header in future release notes, and have faith 
Worst case 4.25 is our safe bet, and thats not such a bad worst case.
Im hesitant to disable a feature that provides a ~40% performance boost across the board just for water. I might stick with old-school mesh displacement and material trickery for water for the time being. Im curious about experimenting with not using instanced stereo and just using aggressive mono culling now 
Could have some interesting ramifications.
4.25 might be fine . But I want to use the new Control Rig functions.
Clouds do not work, Stereo Enabled or Not, Does anyone know if TrueSky Clouds work in 4.26? And if there is a bug report for the 4.26 Clouds?
Hi - Any movement on this problem? Has anyone found a work around for the Volumetric Clouds issue?
Question there: how do you use Mono culling? I understood that the feature has been removed in 4.22 as per <link>?
With water, even with instanced stereo off, I’m getting weird culling issues where seemingly random squares of water are culled only in VR. Anyone else had this issue? Anyone found a workaround?
1 Like
I am also still interested in the topic and would love to see VR support for the 4.26 volumetric clouds.
I made some progress on this topic. The version of the Volumetric clouds plugin in UE4.25 works in VR with “mobile HDR” disabled and “instanced Stereo” enabled. But the cloud material has very limited customizability and the performance is terrible compared to the UE4.26 clouds. See here:
2 Likes
The Volumetric Exponential Height fog also works in VR with UE4.26. See here the fog swirl in the foreground:
Exponential Height fog and Volumetric clouds use the volume materials.
Removing the volumetric advanced Output also doesn’t make the clouds visible on both eyes. So I would assume the problem is not with the volume material itself.
I’ve looked into the Volumetric Cloud Component C++ file to maybe fix it, but I have no idea what’s going on or where the problem might be. I thought of looking into the source code of the 4.25 plugin version, but I can’t find the code.
I just testet it and the Volumetric Clouds now work in VR in Unreal Engine 5.0.0 Preview 1.
I am certain they did not work a few months ago when I last checked before but they do now.
The volumetric clouds work in UE4.27 now as well in VR, but the rendering is bugged, it jitters and the clouds on the left eye are render over all solids. It would be cool if the fixes that are already in UE5 also get ported to UE4.27.
If you want to fix it yourself you need to build UE4.27 from source and change these two lines: https://github.com/EpicGames/UnrealEngine/commit/3808796330293133103b009ac630c716c1de6fc1
2 Likes