Stutter when looking sideways

[Qcumber]

4 hours ago, dutchili said:

The biggest difference i could create are with:
- In game fps setting (60,while headset on 90)
- Oculus Quest 3 sharpening
- Oculus quest spacewarp (needed with 45 FPS per eye), but sometimes when the CPU processes cannot keep up, there seems some kind of desync as the in game FPS counter is still around 45 but i perceive a lower value.

Sorry if this has already been said but have you tried setting refresh to 72hz and aiming to maintain 72fps? 

[SlipHavoc]

I see a couple people in this thread recommended disabling/removing Tacview.  On my system, Tacview was causing a big stutter about every second on my system, most noticeably in scenarios with lots of units.  Disabling it in the Options menu completely fixed that stutter.

[dutchili]

I overclocked my CPU to test the effect.... now there is a fix -> too much work per thread causing the issue.

[dutchili]

@BIGNEWY Can we expect any improvements on May 21st with respect to the ground jitter? It is very annoying.

[AhSoul]

I still see the 'side stutter'. This is when I'm locked at the 72fps to match my 72hz headset refresh, and like 30% gpu headroom according to openxrtoolkit overlay.

Removing TacView didn't help. Everything is smooth out the front of the cockpit, but looking to the sides I can see bushes or buildings skipping a bit.

[Qcumber]

37 minutes ago, AhSoul said:

I still see the 'side stutter'. This is when I'm locked at the 72fps to match my 72hz headset refresh, and like 30% gpu headroom according to openxrtoolkit overlay.

Removing TacView didn't help. Everything is smooth out the front of the cockpit, but looking to the sides I can see bushes or buildings skipping a bit.

Locking at 72 makes it worse for me. 

[AhSoul]

7 minutes ago, Qcumber said:

Locking at 72 makes it worse for me. 

Hmmmm that's interesting..... Are you saying I'm better off just letting DCS render at whatever FPS it can?

[Qcumber]

1 hour ago, AhSoul said:

Hmmmm that's interesting..... Are you saying I'm better off just letting DCS render at whatever FPS it can?

Try it and see how it looks. I have tried a range of settings based on reading various forums. Sometimes it helps locking at about 73-75 FPS. As soon as I get to 72 I start getting a slight stutter when looking around the cockpit. Particularly moving my head forward to look at instruments. Increasing to 73 FPS lock and all is smooth again. 

To be honest though it doesn't really change the frame time stability. I can still sometimes see jitters looking sideways when the frame times are a solid line. 

[AhSoul]

Hmm I'll try unlocked and 73 then - see if it feels any different

6 minutes ago, Qcumber said:

Try it and see how it looks. I have tried a range of settings based on reading various forums. Sometimes it helps locking at about 73-75 FPS. As soon as I get to 72 I start getting a slight stutter when looking around the cockpit. Particularly moving my head forward to look at instruments. Increasing to 73 FPS lock and all is smooth again. 

To be honest though it doesn't really change the frame time stability. I can still sometimes see jitters looking sideways when the frame times are a solid line. 

 

[AhSoul]

9 hours ago, Qcumber said:

Try it and see how it looks. I have tried a range of settings based on reading various forums. Sometimes it helps locking at about 73-75 FPS. As soon as I get to 72 I start getting a slight stutter when looking around the cockpit. Particularly moving my head forward to look at instruments. Increasing to 73 FPS lock and all is smooth again. 

To be honest though it doesn't really change the frame time stability. I can still sometimes see jitters looking sideways when the frame times are a solid line. 

Put the DCS FPS target to 300 in settings and turned off the throttle in openxrtoolkit and bam - no side stutter! It's silky smooth. Thanks so much for suggesting to change it!!!

[dutchili]

4 hours ago, AhSoul said:

Put the DCS FPS target to 300 in settings and turned off the throttle in openxrtoolkit and bam - no side stutter! It's silky smooth. Thanks so much for suggesting to change it!!!

Does it still work if you try it again after rebooting the PC or doing multiple missions?

[Qcumber]

5 hours ago, AhSoul said:

Put the DCS FPS target to 300 in settings and turned off the throttle in openxrtoolkit and bam - no side stutter! It's silky smooth. Thanks so much for suggesting to change it!!!

I still get it sometimes but not nearly as much as I used to. It depends on the map I think. 

[AhSoul]

6 hours ago, dutchili said:

Does it still work if you try it again after rebooting the PC or doing multiple missions?

Not sure yet. I played for 3.5hrs in Pretense and it was glorious.

I'll try again later and see if it's the same.

Edited May 9, 2024 by AhSoul

[AhSoul]

Just went on and tried it again. This time Syria / Apache in single player with a bunch of units doing various things around the map.

Again silky smooth, no stuttering when looking sideways. Pretty much perfect TBH....

[dutchili]

I tried lowering PD as a final try to improve performance. I came from 2.0 and reduced it to 1.3 to get rid of the stutters.
All other settings are still maxed out. 
In 1.3, MFDs are not crisp and the clouds shimmer, but at least the gameplay is good. Hoping for some magic on the May 21st update.

[Qcumber]

3 hours ago, dutchili said:

I tried lowering PD as a final try to improve performance. I came from 2.0 and reduced it to 1.3 to get rid of the stutters.
All other settings are still maxed out. 
In 1.3, MFDs are not crisp and the clouds shimmer, but at least the gameplay is good. Hoping for some magic on the May 21st update.

You should not need a PD of 2.0. What is the oculus output set to?You should have the resolution slider far the the right for 2700 pixels. Then use open xr toolkit or oculus debug tool to set additional resolution modifier to about 1.3; overall resolution to about 3500 pixels. This will give you good visuals. 

[dutchili]

@cucum66 upscaling helps, but you can't generate details that were not rendered in the first place. The best visual results are achieved with pd, but also the worst performance.

[Qcumber]

6 minutes ago, dutchili said:

@cucum66 upscaling helps, but you can't generate details that were not rendered in the first place. The best visual results are achieved with pd, but also the worst performance.

PD is just another form of upscaling. It is considered better to upscale using the oculus software than in DCS. 

Have you tried using Quad Views Foveated Rendering to balance the quality vs performance? 

[dutchili]

It seems indeed that upscaling with Oculus gives a bit extra. I can try upscaling in the debug tool again because i haven't tried that in a long time.
I am not using quad views or any third-party software. I did try OculusVR versus the standard OpenXR and didn't notice any significant difference. (perception, not measured)

[Qcumber]

5 hours ago, dutchili said:

It seems indeed that upscaling with Oculus gives a bit extra. I can try upscaling in the debug tool again because i haven't tried that in a long time.
I am not using quad views or any third-party software. I did try OculusVR versus the standard OpenXR and didn't notice any significant difference. (perception, not measured)

QVFR might be worth a try. It allows you to keep high res in the centre and reduce the peripheral res for a performance boost. You can adjust the settings so you don't really notice the edges. 

https://github.com/mbucchia/Quad-Views-Foveated

[Glide]

The only way to eliminate this issue, called Judder, is to maintain FPS equal to your refresh rate.  Set your headset to 72hz, and tune your settings to maintain 72fps. Judder happens all the time when you are GPU bound because the system is sending "old" frames which are slightly out of sync with the game. 

This video is a bit dated, and it's mostly about Unity, but the concepts are the same for every system.

 

[dutchili]

I guess all VR users are CPU bound, unless they have create setting well beyond the GPU capabilities

 

[Glide]

Not quite true.  When you achieve 72fps with 72hz, you are CPU bound.  To be GPU bound, you can set your refresh back to 120hz, and raise the settings that impact the GPU.  Be careful you don't exceed your VRAM limit.  When you are GPU bound, with the system will give those judder effects because of the old frames.  Easy way to test this, set the refresh rate to 120hz, and lock the frame rate to 30fps.  This is the extreme case.  Looking straight ahead you don't notice it much.  I prefer being GPU bound and just not looking out sideways, however, in a dogfight, the aircraft that whiz across your view port will be juddering.  Watch the runway lights as you take off to clearly see the juddering. 

I should note this is not something DCS can solve, and it does not mean there's something wrong with your system.  It's built into VR.  Every VR game will do this, and every headset will see this.  ASW, motion reprojection, smart smoothing, etc. are supposed to solve this by creating synthetic frames that try to compensate for the timing issue, but that's a work in progress.

Edited May 14, 2024 by Glide

[Rifter]

8 hours ago, Qcumber said:

PD is just another form of upscaling.

Not exactly. The PD has a defined relationship to the native resolution of the headset displays. Your PD can be smaller or bigger than the native resolution. Cranking up the PD beyond the headset resolution is called supersampling.

Upscaling means to render at a resolution lower than the resolution of the headset and then stretching the resulting image to fit the resolution of the headset => performance.

Supersampling means to render at a resolution higher than the resolution of the headset and then shrinking the resulting image to fit the resolution of the headset => quality.

Edited May 14, 2024 by Rifter

[Qcumber]

1 hour ago, Rifter said:

Not exactly. The PD has a defined relationship to the native resolution of the headset displays. Your PD can be smaller or bigger than the native resolution. Cranking up the PD beyond the headset resolution is called supersampling.

Upscaling means to render at a resolution lower than the resolution of the headset and then stretching the resulting image to fit the resolution of the headset => performance.

Supersampling means to render at a resolution higher than the resolution of the headset and then shrinking the resulting image to fit the resolution of the headset => quality.

 

You are of course correct. I meant super sampling. My error. 

Edited May 14, 2024 by Qcumber