Does RTX work in VR?

Is it possible to have RTX working with VR?
I’ve tried playing around with it in 4.26 and it only worked in the left eye. The other eye lacked any rtx features. (this issue is also present in 4.25 with AO)

I know there are performance concerns but with something like a 3080 / 3090 and VR DLSS it should be possible for some types of scenes and settings.

The issue at hand is if it’s even possible due to it curently only working with one eye. Did anyone get it to work?

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No one else tried RTX with VR?

According to NVidia, it’s supposed to

Ray Tracing - GeForce RTX GPUs have dedicated ray tracing hardware that enables real-time ray tracing for immersive and realistic lighting, such as shadows and global illumination, while still maintaining the high frame rates needed for VR.

Source : Great VR Requires a Great GPU

However, I am still waiting for my RTX card, so I haven’t tried yet.

Yes; 3080 owner here. RTX and DLSS are seriously over hyped and should not be implemented. In the case of DLSS, the performance gain is only there at the lowest quality levels which impact the graphics fidelity of the scene so much so that the art design data is lost completely. At the high quality DLSS settings, there is less visual fidelity lost in the art assets, but there is actually a performance penalty for enabling DLSS at any “Quality” setting. Your net FPS will go down with DLSS enabled. It makes no sense honestly if you listen to the marketing fluff that Nvidia is shilling.

For RTX, it’s pretty much the same. There is a huge performance hit when enabling RTX. There is also no good reason from the art department to enable RTX when they can develop examples of fantastic looking lit scenes without any RTX and keep FPS high.

It’s a lose-lose if you’re talking RTX and DLSS in 2021. I don’t see it getting better either in the short term. We need another generation or two of GPUs before RTX is really viable, especially at the resolutions high quality VR demands. Meanwhile the art dept is going to get increasingly good at making lighting without RTX continue to look exceptionally well and hyper realistic. No RTX needed.

There is more of an argument that could be made for enabling HDR then there is for RTX/DLSS. We just are not at a point in technology where GPUs are fast enough to do RTX at 4k+ resolutions. Nvidia should be more direct and tell devs that you MUST enabled DLSS and RTX together and do so at above 4k resolutions. This is the only point you will start to see a DLSS benefit, at that’s still an argument to be made. Because at this point, you’re pushing a 3080 to the limit and even the 3090 is going to struggle at this high of a resolution and quality bar.

Let’s have this question come up again in 3-5 years and see what’s changed honestly. Right now in 2021, it’s a meme.

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Thanks for your comment but that is not at all what I am debating in this thread.

Yes there are issues with rtx, but there are reasons why we need it in our work. The main ones being there is no true reflection and GI solution that works with run time generated meshes without baking or manual in editor setup.

The performance requirement of at least a 3080 is also a non issue in our case.

The issue at hand hough is the mere fact that it straight up doesn’t work with VR, since only one eye view gets the rtx …

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RTX is not supported in VR in UE4 as of 4.26. I also haven’t heard of any plans for that to change.

Currently my hopes are:

  1. Perhaps UE5’s lumen will be VR-capable and will give better lighting results than we have available now in VR.
  2. nVidia is doing a lot with lighting, RTX, and VR. My guess is if anyone adds support for it, it would be in nVidia’s branch.

All speculation at this point though.

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Replying to myself based off the UE5 preview. Right now lumen doesn’t work at all in VR (left or right eye). Nanite works in the left eye only.

I’ve heard they plan to support some of this in VR by full release though. Here’s hoping!

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i saw a live stream a month ago he said for nanite its possible they just need to code it in (for lumen)

Came across this question, Real time ray tracing is supported for multi-view rendering and VR since 4.24 Cited Release Notes

I haven’t tested but eager to try.

ray tracing might work but hits me too hard on 2070

What the actual? Im sure I heard that for as recently as 4.26 that ray tracing in UE4 for VR is technically impossible. Can anyone who has tested this please weigh in? Id be interested to know - for example does the engine try to do ray tracing like it also tries to do lens flares and stuff if you turn it on, but its kinda dodgy? Or does the engine let you hit the checkbox but then does nothing because in VR?

Also, sidebar, can anyone say with a straight face that they can achieve a decent frame rate with a decent rig using ray tracing in real-time, even in a traditional flatscreen game?

Bump RT in 4.27 - wondering about your enabled options - or VR Console Commands - like Stereo On/Off
Enables or Disables stereo rendering for Head Mounted Display (HMD) devices.

vr.PixelDensity
Sets the resolution of the VR panel. Use a higher number for better quality, and a lower one for better performance.

Stereo rendering had no effect. RTX GI still only present in one eye.

Changing the resolution doesn’t matter if it’s only visible in one eye.