Stuttering at Close range.

[shu77]

I've just Started with VR over he weekend with a new Rig and a Reverb G2.  Followed Big Newy's settings in his post and while the game seems to be happily offering 90FPS I am noticing at Low level on the Caucaus Free flight close objects seem the stutter on the right hand side, or ghost by while things that are either further away or on the left go fine (only seems to happen out the right hand side of the ship, not on the ocean side) Head Tracking is fine, FPS is fine, it just seems to be some kind of issue when theres a lot of object on one side, so Im not quite sure if this is stuttering or ghosting or something else, I'd be interested if anyone else has seen something similar or how to properly describe it. 

[BaronVonDoon]

I had my G2 this week too I had this issue too, even though I was getting 45fps (everything was maxed) at ground level, looking left or right was a stuttering mess. Straight ahead was fine. 

 

I switched on legacy reprojection in the per app setting in steamvr, which seems to have fixed it. Not sure if that's what I want to be doing, but for now it's smooth 

 

Using a 5800x/3080

Edited February 21, 2021 by BaronVonDoon

[speed-of-heat]

do you have shadows on?

[GunSlingerAUS]

You're getting 90fps??? Wow. Lucky you.

 

If you're seeing this when you are passing aircraft at close range, or looking sideways out of the cockpit at the ground, it's likely reprojection artefacts. These should only display when you're running at an fps lower than the HMD's refresh rate though. So if you're getting 90fps (unlikely, given most people struggle to get 45fps with a 3090 and G2), you shouldn't be seeing it. If you are, there is unfortunately no way to get rid of it - some VR players apparently don't notice this at all, while others (like me) are extremely sensitive to it. This is the main reason that I don't use my G2 with DCS (I have a 3090 as well). 

[captainHelmet]

I have reprojection forced off and still see objects ghosting when looking out the side of the plane.  Ill see double of Things like power lines or other planes.  Even with one eye closed it looks like the same object is rendered twice in one frame slightly offset.  I have cockpit shadows on high, and ground shadows set flat with the flat shadow removal mod. 

[shu77]

Yeah I have shadows on Flat at present is it worth dropping them? 

DCS is suggesting 90FPS is there some other way to monitor without FPSVR? 

[speed-of-heat]

Without knowing your settings in detail it’s about like playing whackamole but shadows and aa are usually to blame...

[shu77]

5 hours ago, speed-of-heat said:

Without knowing your settings in detail it’s about like playing whackamole but shadows and aa are usually to blame...

Thanks, TBH I wasnt quite sure how to describe the problem, as it was odd and only when looking out the side of the aircraft that had a lot of terrain on it, I wasnt getting the same issue when looking at Terrain that had ocean behind it so Shadows would make sense, as would the Reprojection method, so I am going to play with those two and see if that helps, I'll post my settings once  I get a little further on.

 

Is there any indication on what impact the DCS resolution has? I notice BigNewy has 2560 x 1080 and Thud suggests 3480x2160, I'm thinking both might just be using the resolution of their native monitors? 

 

[shu77]

Tried a couple things, turned off Shadows, enabled Legacy Reprojection which seemed to help, the stuttering is still there on the edges, but not as bad. 

I also added the IC Compliant VR Shaders from this thread: 

 

But without any real baseline its difficult to tell if its normal or not.

 

Have upped native resolution to 2560 x1440 and Have Steam sitting on about 60%.  Still getting between 75 and 90 FPS, went for a run through Syria tonight and found the performance ok. The 3080 seems to be performing fairly well against what other people have suggested from the 3090 which seems reasonable given how close the benchmarks place it. Will See if 2.7 adds any improvements.

 

[speed-of-heat]

not quite sure what you are saying but for clarity resolution in game (options ->System -> resolution) only has functional impact in 2d world, the only thing that impacts VR is is the Steam SS and in Game PD settings

[shu77]

Thanks for the pointer on the DCS resolution, have been wondering about that. 

[speed-of-heat]

also make sure hags is turned off ; and motion smoothing is on 

[shu77]

I tried the other items in your 3090 set up guide that seems to have helped too the stuttering is still there, but no where near as bad as before, I will play a little further with the legacy reprojection and Smoothing now I have a good base, but it does seem quite workable now.  Just need the Australian weather to cool down enough to want to have a headset strapped on for long periods now. .

[speed-of-heat]

yeah the legacy reprojection is confusing to me but if it works for you i'm not going to knock it 

[Big Daddy]

Hi shu77, after struggling with your problem for a couple of days I finally found the solution!!! I also tried the legacy mode and it worked but with artifacts at the borders of the screen. Well it turned out my MWR for Steam VR settings were wrong.

 

Make sure the following file: E:\SteamLibrary\steamapps\common\MixedRealityVRDriver\resources\settings\default.vrsettings

has the line: "motionReprojectionMode" setting set to "auto".

 

Mine was set to "none"... As soon as I changed this to "auto", set the steamVR settings for DCS to Motion Smoothing: "Enabled" and turned the legacy reprojection setting to "OFF" it was all butter smooth..!

 

Hope this helps!

[speed-of-heat]

That is not how you turn on motion smoothing reprojection anymore, it will be overwritten on each update.

 

please see my settings, wmr for steam Vr settings...

 

The line needs to be commented out, setting it to none, is also equally wrong.

Edited February 22, 2021 by speed-of-heat

[shu77]

I worked through Speeds set up guide but I think the thing I missed was the WMR for Steam Settings, is there a trick to getting into them? thinking back through I couldnt find the screen in  your guide so I skipped over to the next step.  

[shu77]

I found and updated the WMR Settings in Steam, one of the things I noticed is that this cut my FPS from 90 to 45, I tried a few configs people suggested with Smoothing on/Off and Legacy Reprojection on/off Im not sure either really helped, I'm starting to think the issue is to do with the trees in the caucaus Hornet free flight area as it seems to be worse when theres a lot of trees on screen. Its useable now, its just noticeable when looking out the side of the aircraft which you seem to do a lot more in VR. 

[speed-of-heat]

the 90-45 is expected behaviour when motion smoothing is forced on, there are three modes

 

- off, which gives you real time FPS based upon the current frame time of the GPU or CPU which ever is worse, but there is significant stuttering

- enabled, which gives you 90 (or max refresh rate for the headset) or 45 (or half frame rate for the headset) or less than 45 (or half frame rate), if your GPU and CPU frame times are less than 11ms you will get 90, other wise you will get 45fps with the GPU essentially "guessing" every other frame, or if your frametime is above 22 ms you will get the same behaviour as off

- forced, gives you what you have which is 45fps up to 22ms frame time and then the same as "off"

 

some people see or are troubled by the "lurch" that can take place between 90 and 45 and so use forced, i honestly don't so i just leave it enabled.

Edited February 23, 2021 by speed-of-heat

[shu77]

Yes I think the next step is pushing the processor up from the stock 3.7Ghz.

Edited February 23, 2021 by shu77

[speed-of-heat]

yep that will make a huge difference, depending on your cooling solution you should be able to get it up beyond 5Ghz

[shu77]

Yeah to be honest Im starting to think the issue is not any of the above. "Use Steam settings" for WMR with Force always On for the Per App in Steam VR seemed to work for Caucaus but turned Syria into a Jittery mess.  Turning WMR to Auto and SteamVR to On and Legacy seemed to deal with that to an extent, but it doesnt seem consistent. I might try the overclock as a next step and see what difference that makes. 

 

Edited February 23, 2021 by shu77

[speed-of-heat]

i can't remember @shu77 do you have FPSvr? if so that should help diagnose some of the frame times 

[shu77]

No, I may have to do that, Im going to start with some overclocking and see what difference that makes.  Looking at your specs there is really no noticeable difference in our setup beyond the fact you are running @ 5.1 and I'm running @ 3.7.  I really dont rate the difference between the 3080 and 3090 being that much of a difference. 

[speed-of-heat]

Don’t rule out gpu memory... Syria and the Chanel both take up vast quantities of  gpu memory.

 

but a lot of the difference will be cpu frame time based upon your current 3.7.