Pimax 8K X with OpenXR

[Rangoon]

I'm trying to get my Pimax working with OpenXR in DCS. I am seeing a double image. I believe with SteamVR, turning on "Compatible with parallel reprojections" would fix that. But now that just seems to leave me with a double image or blurring when I turn my head. 

Is there something within the OpenXR Toolkit that might fix this? Or is it something within PiTool?

I have read about people using PiTool version .263. Is that generally considered the best version to use? Might that fix my issue?

I've tried locking framerate to 45fps and I am not using motion smoothing. 

[Brzi_Joe]

No double vision for me, and no need for paralel projections.

Disable foveated rendering in OpenXR toolkit, that is currently broken for dcs (untill DCS and OpenXR toolkit update that).

Also be sure to disable OpenXR toolkit zoom - that will sure make double vision.

ps: I use latest pitool

ps2: check if you really have latest Openxr toolkit, and OpenXR for pimax. Uninstall old, and reinstall new.

 

 

Edited December 12, 2022 by Brzi_Joe

[WipeUout]

This sounds like you are super sampling with PiTool.  Leave this (Render Quality) at 1, restart your computer but make sure to completely unplug and re-plug your HMD from the computer before you restart it.

If you want to super sample, use pixel density (PD) within DCS but not too much because unlike a resolution slider, PD will jump quickly to a high super sampling value.  PD 1.1 = 121%, PD 1.2 = 144%, PD 1.3 = 169%.

OpenXR is more efficient than SteamVR but not with AMD cards, much better with nvidia.  I found that neither FSR nor NIS provide good results, I use Fix Foveated (in OpenXR) instead with a good performance uplift of 1.1ms in my GPU FT and no loss of quality in the center image.  The wider field of view of the pimax is better suited for Foveated.  Unfortunately, PiTool Foveated rendering does not seem to work with OpenXR but the OpenXR Fix Foveated setting works fine. 

Edited December 12, 2022 by WipeUout
update

[Rangoon]

Thanks for the input, you guys. Foveated rendering is disabled, and no zoom is set. I'll double check the toolkit version, though I just downloaded it yesterday. I have my super sampling set to 1.0 in PiTool (I used to have it set to 0.75 for DCS with SteamVR, but moved it to 1.0 thinking I would do anything like that in the Toolkit - it's also at 1.0 in DCS). 

I'll try unplugging the headset and restarting.

I'm using an RTX 3080Ti (with i9-12900k and 64GB RAM). 

I'm just trying to get things working on a fundamental level here, so I haven't really even played with any other settings at this point. Just have the performance overlay turned on.

[Phantom88]

If You are running Windows 11 make sure HAGS is turned off in your Windows Settings....It can have a very Bad effect on VR

[Rangoon]

29 minutes ago, Phantom88 said:

If You are running Windows 11 make sure HAGS is turned off in your Windows Settings....It can have a very Bad effect on VR

That was definitely the problem. Thank you!!

[Slammin]

I can't remember the details, but I do know that I used the Global method for the OpenXR DLL api when I installed OpenXR for my 8kx.  My DCS is the Steam version in case that makes a difference.  I have not had any issues.  One strange thing I did notice with DCS, and this is even before I installed the OpenXR stuff is that setting the in-game PD to anything above 1.0 would result in a very crappy screen.  Before VR, I had always set in-game PD to 1.2.

Just to make certain this isn't a lighthouse issue, you might want to make sure they are not too close to your position.  Also, if they are v1.0 lighthouses, they need to be able to see each other.  I mention this because I seem to remember my 8kx freaking out with double-vision issues due to bad lighthouse location.

[WipeUout]

I just switched the 8k+ for a refurbished 8kX by Pimax.  Wow, what a difference!  Running native 4k at 60hz with no repro or MSAA and the image is simply stunning.  Resolution is the cure to aliassing, MSAA is not required anymore.  Running at 60hz gives a lot of breathing room and I can use low shadows, normal clouds, medium water, high textures in any scenario without exceeding 16.7ms frame time.  Of course there is always the exception such as missions created for DCS-liberation that eat up your CPU like crazy.  But even in Syria, I am flying without need for any reprojection.  Native 4k per eye is so beautiful!

Unfortunately DCS Native OpenXR introduced with 2.8.2 does not work good for me though.  I had to revert back to using opencomposite instead of the command line switch to force OpenXR.  Even using Pimax XR 0.3.0 and OXRTK 1.2.4 did not help.

The issues I had were two fold:

1. Stutters when moving my head up/down right/left.  

2. Blurry image out of focus or having left/right image synch problem.

Going back to PimaxXR 0.2.8, OXRTK 1.2.1 and opencomposite 0.6.3 solved the issues.

Wonder if this only related to the 2075 serial number 8KX or also present in 2076 models?

Edited February 7, 2023 by WipeUout
Typo

[void68]

I noticed the same problems with my 2076 model. Ran fine 1 month ago or so. Totally wrecked after any of the updates, I think it began with the OpenComposite update and then I switched through PimaxXR and OpenXR Toolkit like you.

A question, do you use the OpenComposit openvr_api.dll or the DCS native one? With the native one I got no microstutters but all Texture setting above low lead to an OpenComposite error. With the OpenComposite .dll I get these stutters.

 

Then:

opencomposite 0.6.3 solved the issues

I fail to locate this file, do you have a link? Do you mean the Open Composite Runtime Switcher? I just found one file without any versions.

 

edit: error with the OC .dll (1,7MB), back to DCS .dll (580KB) and it runs. Didn't change the updated OC Runtime switcher.

 

System runs again, thank you! Tried to get it back running for almost a week!

Edited February 7, 2023 by void68

[WipeUout]

50 minutes ago, void68 said:

I fail to locate this file

I use now the opencomposite dll to switch from OpenVR to openXR runtine and bypass DCS native OpenXR.  This version (0.6.3) is the one that works fine with PimaxXR 0.2.8, it is attached and it goes in the dcs\bin folder, as you probably know.  If I you want to use the DCS native openXR support, you do not need the opencomposite switcher but need to have PimaxXR 0.3.0 and OpenXRtoolkit 1.2.4, and add two arguments to the command line (see first subject in vr forum), but in my case, it does not work well.

openvr_api.dll

Edited February 7, 2023 by WipeUout
update

[void68]

From what I understood - but I am lost already - that native OpenXR support comes with the actual beta version of DCS only?

The Openvr_api.dll does not run... error. So I use the old version like you, the Composite Switcher and the DCS original openvr_api.dll.

Strange

[WipeUout]

Yes, the OB 2.8.2.35759 only.

Very confusing indeed but the first two post here are very clear and detailed:

https://forum.dcs.world/topic/318004-dcs-now-supports-openxr-natively/

[void68]

New day, new chances. So, today I took your openvr_api.dll attachment file from the post (and not the one - to me identical(!) - version on my drive and amazingly it runs, too (the original .dll worked amazingly well)! I remember OpenComposite Switcher updated 2 weeks ago and the mess started and then I updated all other tools. As I neither get version info on the switcher nor the openvr_api.dll so I considered them being the same. How do you know that this is 0.6.3? I checked version history in the file's properties, no info at all.

Quote

this version (0.6.3) is the one that works fine with PimaxXR 0.2.8, it is attached and it goes in the dcs\bin folder, as you probably know.

I'm back in the skies, guys!

Edited February 8, 2023 by void68

[WipeUout]

5 hours ago, void68 said:

How do you know that this is 0.6.3?

When I downloaded it, I created a folder for OVGME and labelled it "OpenComposite 0.6.3"... 

[WipeUout]

OMG, finally got OpenXR to work with DCS Native support from latest OB version.

I did not have Pitool 284 installed and this was causing the issues.

The results are stunning, I have a GPU frametime improvement of 1.0ms and even a CPU improvement of 1.3ms with same settings running my test track file.

   

[void68]

I got .284 and it didn't work with native support. I wonder why PiTools didn't tell there was a new version.

Edited February 16, 2023 by void68

[WipeUout]

2 hours ago, void68 said:

I wonder why PiTools didn't tell there was a new version.

1.0.1.284 is a beta version, not the official release.  I was running on .277 and pitool never signaled me that there was a newer version.  After installing .284, I was notified by pitool that a new firmware was also available and I installed it.   This might be the issue you have but the recipe for DCS native OpenXR support to work is:

DCS OpenBeta 2.8.2.35759

Pitool 1.0.1.284

PimaxXR 0.3.0

OpenXRToolKit 1.2.4

No OpenComposite

Start DCS.exe with command line arguments: --force_enable_VR --force_OpenXR

...and the magic should work.

 

[void68]

Thank you, I'll try once it's out of beta state.

[Talvid]

Hello all,  do you have to run your monitor through the HDMI port on your motherboard so the GPU can run the Pimax?

Edited March 3, 2023 by Iceman555

[WipeUout]

Pimax does not use HMDI, it uses display port.  The HMD has to be connected through one of the GPU connector or it will not work.  Usually, you have three display port connector on your GPU card. 

[Talvid]

3 hours ago, WipeUout said:

Pimax does not use HMDI, it uses display port.  The HMD has to be connected through one of the GPU connector or it will not work.  Usually, you have three display port connector on your GPU card. 

Thanks, I have my monitor and Pimax connected to my card.  I tried out DCS, it was so jittery, every time I look around the screen shakes.  Anyone else have this problem?

[WipeUout]

3 hours ago, Iceman555 said:

I tried out DCS, it was so jittery

You need to provide more info, what are your settings (pitool, DCS Stable or OB, OpenXR or SteamVR, etc) and what is your hardware...

 

Edited March 3, 2023 by WipeUout
Typo

[Talvid]

15 hours ago, WipeUout said:

You need to provide more info, what are your settings (pitool, DCS Stable or OB, OpenXR or SteamVR, etc) and what is your hardware...

 

 

Pimax store, OpenBeta, Open XR Toolkit (rez size 60%, DCSVR pixel density 1.5, cockpit quality high, terrain quality low, PimaxXR:on , steam vr : bypassed, RTX3080, 64GB RAM, Ryzen9.   

 

I did a Windows reset my PC and set openxr toolkit upscaling/sharpenin to OFF and i did the --force lines of text in the DCS.exe shortcut settings . I'm now in running super smooth thanks for the motivation!  I think that 1.5 pixel density is 150% resolution isnt it?  Without it set at least that high, I cant even make out the lettering on the gauges on the cockpit panels.

Edited March 4, 2023 by Iceman555

[WipeUout]

Ok, a bit of math first.  You have a pixel density of 1.5, which increases your resolution by 225% but also, you reduce resolution to 60% in OXRTK.  Assuming you have an 8kX, you are effectively reducing your final resolution at 90%, or 3456x1944 pixels.  Set pixel density to 1, and use only OXRTK to change resolution as it will be more efficient.

Unless you reduce the demand on your system further, the jitter will not go away because your GPU can't keep up with that much pixels to render.  If you want to keep close to native (100%) resolution, then you will have to consider using smart smoothing or 1/2 vertical synch (smart smoothing, but always on).  Which bring me to another important aspect: what is your HMD's refresh rate?  My 8kX is an older model that has 60/75/90 hz refresh rate and I use the lowest.  If you have the newer model, you may have 90 hz only as an option.  This means that your GPU must pump 90 FPS in order to have a smooth video and with a 3080, it is too much.  You need to use smart smoothing or drop the resolution considerably. 

The other way is to reduce DCS settings.  Disabling shadows completely, clouds to low, all the AA features off and keeping all texture low will help. 

You can also improve performance by enabling fixed foveated rendering in OXRTK, that is what I do an the performance gain is substantial.  Note that Fixed foveated rendering option in Pitool does not work in DCS, you have to use the option in OXRTK.

Getting a smooth experience in DCS, no matter what is you HMD, is a balancing act that we all spend way too much time on.  It is the price to pay for the most immersive VR experience.

Last bit of advice, Pimax is a great HMD but it requires lots of horsepower to fully enjoy it.  Save and get yourself a 4080 or 4090.

Edited March 4, 2023 by WipeUout
Typo

[Nahemoth]

Hi,

 Is there any improvement in switching to .284 beta version of Pitool? I continue with the current stable version, over the 8KX old version at 60Hz, and everything works fine with OpenXR.

Thanks