OpenXR Toolkit Tuning Guide (updated 21/02/23)

[edmuss]

Unfortunately reprojection just isn't as good as WMR4SVR, SVR or oculus, the image quality suffers and occasionally the performance dives massively (I think related to lack of VRAM); this is in addition to the substantial artifacts which are arguably much worse than any other option.  The devs are aware of the issues with DCS but I don't know how high it ranks on their list of things to fix; I understand that it was quite a tricky issue to solve.

On the plus side openxr without reprojection is much smoother than SVR so higher framerates aren't so critical but you have to accept that there will be a more ghosting as you get close to your half refresh rate.  Essentially without reprojection, if you're not achieving refresh rate then openxr will render at half refresh and wait for the next frame to be ready; the FPS shown is an average based on the time it's waiting for refresh - in reality it's only rendering at 45Hz but it's a useful performance metric to have (this is my understanding of it, someone please clarify if it's wrong).

[Burt]

I’m totally opposite. I get better clarity and less jitters with motion repo enabled and performance is fantastic. I’ve tried without it and no matter how much I slide things around it looks and feel terrible. 

G2 @90hz - 100-NIS- 100 -15%sharpness Motion repo enabled

[edmuss]

The hateful thing about VR is everyone's experience is completely different

[Burt]

That’s so true ! 

[Digitalvole]

4 minutes ago, edmuss said:

The hateful thing about VR is everyone's experience is completely different

Haha so true! 

 

1 hour ago, edmuss said:

Unfortunately reprojection just isn't as good as WMR4SVR, SVR or oculus, the image quality suffers and occasionally the performance dives massively (I think related to lack of VRAM); this is in addition to the substantial artifacts which are arguably much worse than any other option.  The devs are aware of the issues with DCS but I don't know how high it ranks on their list of things to fix; I understand that it was quite a tricky issue to solve.

On the plus side openxr without reprojection is much smoother than SVR so higher framerates aren't so critical but you have to accept that there will be a more ghosting as you get close to your half refresh rate.  Essentially without reprojection, if you're not achieving refresh rate then openxr will render at half refresh and wait for the next frame to be ready; the FPS shown is an average based on the time it's waiting for refresh - in reality it's only rendering at 45Hz but it's a useful performance metric to have (this is my understanding of it, someone please clarify if it's wrong).

Thanks for the info edmuss, and the thread. I’d love to be able to run with no motion smoothing, it looks amazing, but I decided a while back that the hunt for 90fps is a fools errand even with a 3090. I mean it’s never going to happen in mp or Liberation. I’d love to hear I’m wrong though.

Edited July 25, 2022 by Digitalvole

[Burt]

I don’t think there’s any VR game that could run 90fps with all the bells and whistles on even with the newer 13900-4090 ect. If so it will only run 90fps for a seconds. Maybe one day but difinitely not in DCS. Maybe DCS 3.0  

[edmuss]

16 minutes ago, Digitalvole said:

Haha so true! 

 

Thanks for the info edmuss, and the thread. I’d love to be able to run with no motion smoothing, it looks amazing, but I decided a while back that the hunt for 90fps is a fools errand even with a 3090. I mean it’s never going to happen in mp or Liberation. I’d love to hear I’m wrong though.

 

I've hit 85fps on SP foothold caucasus (with a big fistfull of FSR upscaling) and typically 70-75in conjunction with 60Hz means that it's above refresh all the time and wonderfully smooth.  That's largely dependent on your capacity to run the G2 at 60Hz though, some can, some can't.

Running 90Hz means that I have to rely on the built in vsync (the 45hz render with average fps value) which will sync up rotational movements but not translational - therefore if you are looking around it will be a stable image, if you slide sideways in the seat you will get a slight ghosting of the cockpit.  Generally as I'm sat still in the cockpit this minor cockpit ghosting doesn't bother me, if flying at speed low over buildings when looking 3-9 you will see ghosting (seems to get better over 60fps); in a helo it's all so slow that it rarely causes me issues  

If I'm tired then 60Hz blows my eyes out quite quickly (getting too old for burning the candle at both ends!) so I'll switch to 90Hz and live with the ghosting.

Just now, Burt said:

I don’t think there’s any VR game that could run 90fps with all the bells and whistles on even with the newer 13900-4090 ect. If so it will only run 90fps for a seconds. Maybe one day but difinitely not in DCS. Maybe DCS 3.0  

I can run dirt rally 2 at 90Hz with ultra settings and get >90fps, Half Life Alyx is the same - it's just DCS which to be fair was never written for VR and it's amazing it does so well as it is

Edited July 25, 2022 by edmuss

[HoBGoBLiNzx3]

These are something things that helped with OC - OXRTK.  (I run mine at 75%NIS/Override RES ON-default/FFR- 1/2@85 & 1/16, Smoothing at -20)

Adding DSR at the driver level also helps you gain some resolution back at a very minimal cost. You can find it in the Global Setting in your NCP. 

I also add antialiasing in NCP @ 2x (Enhance application setting) So I can enable MFAA. Note: You must have at least msaa 2x on in game to active it. 

- DSR: With the displays in a VR headset resting close to the user's eyes, higher resolution can improve the VR experience. Dynamic Super Resolution (DSR) – which we're introducing with Maxwell – helps us take the resolution from 1 megapixel per eye to 4 megapixels per eye.

DLSS would be a much welcome feature if we ever actually see an update for MCS/Vulkan. 

 

[Digitalvole]

10 minutes ago, HoBGoBLiNzx3 said:

These are something things that helped with OC - OXRTK.  (I run mine at 75%NIS/Override RES ON-default/FFR- 1/2@85 & 1/16, Smoothing at -20)

Adding DSR at the driver level also helps you gain some resolution back at a very minimal cost. You can find it in the Global Setting in your NCP. 

I also add antialiasing in NCP @ 2x (Enhance application setting) So I can enable MFAA. Note: You must have at least msaa 2x on in game to active it. 

- DSR: With the displays in a VR headset resting close to the user's eyes, higher resolution can improve the VR experience. Dynamic Super Resolution (DSR) – which we're introducing with Maxwell – helps us take the resolution from 1 megapixel per eye to 4 megapixels per eye.

DLSS would be a much welcome feature if we ever actually see an update for MCS/Vulkan. 

 

I’ve not played DCS for a couple of months (summer, yay!) but I can see I’m now totally out of the loop. I only understood about 30% of what you typed! Oh dear, I clearly need to hit the books again. I have lots of Google searches to do, but could you maybe just tell me what FFR is? Speed of Heat mentioned that in his guide, is it instead of FSR? I thought NIS was the nvidia version of FSR.

[edmuss]

Fixed Foveated Rendering, it was introduced in fholgers old vrperfkit and is also implemented in openxr toolkit

[Sr.]

14 minutes ago, edmuss said:

Fixed Foveated Rendering, it was introduced in fholgers old vrperfkit and is also implemented in openxr toolkit

Not yet for AMD GPU 

[HoBGoBLiNzx3]

19 minutes ago, edmuss said:

Fixed Foveated Rendering, it was introduced in fholgers old vrperfkit and is also implemented in openxr toolkit

I stated that in my response FFS is kind of a hack imo but it works to save some fps.. You ideally don't want to have to use it. DLSS is a much better option than NIS but needs to be implemented on the development side as well and you need an RTX card.

But let's be honest, who isn't buying RTX cards now... If you're buying AMD, they could also implement that option as well. 

IF you guys haven't given DSR a shot on top, give it a go. I wouldn't use the legacy resolutions but they will work. The other 2 are much better. 

Edited July 25, 2022 by HoBGoBLiNzx3

[Digitalvole]

Thanks guys, I think I turned FFR off because it made the outer edges of the display look wretched. I bet there’s some settings to be tinkered with there though, I shall commence tinkering tonight

[speed-of-heat]

8 hours ago, edmuss said:

No I meant running 3160 resolution and FSR 68% (I think it's about 68 to achieve the 2160 ish render target) vs FSR 150%.

Neither are going to be shimmer free but I've felt that it's lessened by using 150 vs 68.

 

I don't see any difference between 68 and 150 

[edmuss]

10 minutes ago, speed-of-heat said:

I don't see any difference between 68 and 150 

Like I said it could just be placebo, logically it's achieving the same result (upscaling from 2160-3160) so it should be the same; thanks for testing it though  

[speed-of-heat]

no worries, part of the problem of course is you are stopping the game and going back in ... which makes life more complex in doing comparisons 

[Xupicor]

Is FFR doing anything for you guys? I mean, I can see it work, I can adjust the settings, I see the two rings and everything, but even at max performance settings I can't see any impact on FPS. It moves maybe 1 fps up, but fps fluctuate for me way more than that over the time of a few minutes flying, so I can't say it does anything but make stuff look worse.

Is there something I'm missing?

[edmuss]

3 minutes ago, Xupicor said:

Is FFR doing anything for you guys? I mean, I can see it work, I can adjust the settings, I see the two rings and everything, but even at max performance settings I can't see any impact on FPS. It moves maybe 1 fps up, but fps fluctuate for me way more than that over the time of a few minutes flying, so I can't say it does anything but make stuff look worse.

Is there something I'm missing?

Pause DCS and look at the performance overlays whilst cycling the options through. From quality/wide preset to off I gain about 1-1.5ms frametimes, you can get much higher gains (2-3ms I think) but then it looks like ass on the periphery.  It's not a big gain but it's the small incrementals that can mount up

[Xupicor]

I'll try and see with the performance overlay, but 3ms would be plenty noticeable in framerate at around 50 baseline - it should go to around 60 then. In my case like I said, it's ether 1 or maybe not even that, since it fluctuates with or without enabling FFR anyway.

[Grodin]

Any real difference using NIS vs FSR? (I have 3080ti). After many days if fiddling with settings my biggest success was to limit FPS to whatever i can maintain reliably with the minimum graphics i can enjoy - having stable 50 fps makes me much less motion sick than having my framerate constantly go up and down from 60 to 80 for example, all those jumps in framerates make left and right eye images go "out of sync" and cause nausea for me.

 

Is it possible to use FXAA instead of MSAA? MSAA off cause lots of shimmering especially when using FSR but MSAA 2x costs huge performance hit.

Edited July 25, 2022 by Grodin

[Burt]

Ah yes I would like to know that too I have been using NIS just because I have a NVidia card. But I think we can use either or

great question 

Edited July 25, 2022 by Burt

[edmuss]

Performance wise I think FSR and NIS are about the same, the differences are in the sharpening algorithms. I understand that NIS is more aggressive with the sharpening.  Both are software implementation so hardware independent.

Hardware dependent equivalents would be FSR2.0 and DLSS but both would require support to be added into DCS by ED and as far as I'm aware they're not inclined to implement hardware vendor specific code.

Regarding FXAA, I think it can be enabled and it does have an effect but it's absolutely minimal compared to MSAA (both in performance hit and antialiasing quality). I've always turned out off after trying it.

Edited July 25, 2022 by edmuss

[Xupicor]

5 hours ago, edmuss said:

Pause DCS and look at the performance overlays whilst cycling the options through. From quality/wide preset to off I gain about 1-1.5ms frametimes, you can get much higher gains (2-3ms I think) but then it looks like ass on the periphery.  It's not a big gain but it's the small incrementals that can mount up

Absolutely no effect on framerate with FFR on my side. I've used the custom settings mode for 1/16-1/16-1/16 mode, and besides the fact that the whole screen is heavily pixelaterd I can't see any effect on fps or frametime at all. Is this implemented right?

[edmuss]

Something not right there, going from off to FFR 16/16/16 losses 3.5ms - obviously looks diabolical but the saving is there.

It doesn't work on AMD GPUs unless it's dx12 but you're on Nvidia aren't you?

[Xupicor]

Yep, I'm on 3080, absolutely no effect on my fps or frame time. It pixelates stuff, but other than that I can't see any effect on performance.