VR Performance Tweaks & Tips

As many will have experienced, RaceRoom is very harsh on performance in VR, mostly because of the old engine hammering the CPU. I will collect some of the tweaks I learned about and explain them here, so everyone can hopefully benefit from them as well. I am very happy with the performance I have now, as I can keep 90fps with basically all the eye candy that is noticeable in VR on (even shadows!), even on race starts with 20 cars visible. This is on my 4770K @ 4.4GHz and a 1080ti, but I am mostly CPU bottlenecked, so any better CPUs will probably give even better performance, even with a slightly lesser GPU.

OpenComposite (Oculus and Windows 8/10 only)
In search of better performance in RaceRoom in VR I stumbled upon this thread. The instructions were a bit scattered but I gave it a try and it gave me a HUGE performance boost, made the performance more consistent and reduced loading times. OpenComposite is an awesome project by Campbell Suter which replaces SteamVR as the 'translator' for games that do not have native Oculus support. Unfortunately, at this time the main project does not work with RaceRoom, but @The Iron Wolf did an amazing job at adapting the project to work with RaceRoom, which he published as his own fork. He does not use Oculus anymore, so he will not be able to support the project anymore in case it stops working, but so far 3 Betatesters with different hardware tried it and worked for all of us, so hopefully it will work for most people with an Oculus headset.

How to install:

• Go to the x64 folder in the RaceRoom directory (Normally in C:\Program Files (x86)\Steam\steamapps\common\raceroom racing experience\Game\x64)
• I would recommend renaming or backing up openvr_api.dll as this is going to be replaced with the opencomposite DLL, so if it does not work you can restore the original file to use SteamVR again.
• Download the latest v1.0.0.0 DLL file from the adapted project, it will be in a zip together with opencomposite.ini , which is required to set the options for OpenComposite. The download link there doesn't work anymore, so here is a link to the files from a betatester: https://forum.kw-studios.com/index.php?threads/vr-performance-tweaks-tips.13068/page-38#post-249527
• Extract these files to the x64 folder in the RaceRoom directory, if you start RaceRoom in VR now, it should no longer start SteamVR and will most likely crash, as the included opencomposite.ini file is not correct for RaceRoom yet.
• Edit the opencomposite.ini file to the following (make sure it is formatted on different lines and not all on one line):
  supersampleRatio=1.0
  enableLayers=true
  enableCubemap=false
  threePartSubmit=true
  useViewportStencil=true
  dx10Mode=true
  
  You can adjust the supersampleRatio to whatever you want, but it seemed to cause worse performance than setting the supersampling in the Oculusdebugtool myself. You can test this for yourself though. If you want to match your SteamVR supersampling setting they are slightly different: 1.5 here would be equivalent to 1.5x1.5=2.25 or 225% in SteamVR, so you can calculate what the equivalent setting would be for you.
• RaceRoom should now launch in VR without SteamVR launching. This will only work for the 64-bit version of the game.

Some Remarks:

• If SteamVR is still launching with RaceRoom, make sure you have extracted the files into the correct 'x64' folder and not the 'Game' folder.
  
• If the game instantly crashes, doublecheck you have set the correct values in opencomposite.ini. If that is all correct, you could try the other DLL file in the project. If that does not work either, you can either try to play with the settings in opencomposite.ini to see if your system maybe works with other settings. Otherwise, you can revert back to using SteamVR by replacing the DLL file with the backup of the original one you made. You could try asking the original OpenComposite devs for some suggestions, but as this is not fully their work it's a long shot.
• Make sure you have done the room setup in Oculus Home, otherwise it's possible that OpenComposite will not work properly.
• As this is not officially supported for RaceRoom, there is a good chance the files will be overwritten when updating or repairing the game and any update might also cause it to stop working, but since I have only used it for a week now, I don't know yet. Similarly, there is no guarantee it works for everyone and that it improves performance for everyone, so make sure to test for yourself and feel free to report back!

Recommended Graphics Settings
(Removed my old recommendations as they do not really apply to the 2024 graphics update anymore)

 

Interesting, for me shadow split on gives slightly better performance, which it isn’t supposed to do, so I might be the odd one out

 

Will add that to the remarks, thanks!

 

How many cars do you have visible? That is the biggest performance hit you can have. For example on Silverstone, my frametimes are about 7ms with 30 AI on when none of them are in view, but if I have 30 cars visible and all of them in view, or in the mirror the frametimes go up to 13-14ms, so almost double!

 

Updated the original post with an initial settings breakdown

 

I've tested it quickly on VLN with 40 AI, I get around 60-70fps right at the start, but it climbs back up pretty quickly as the field spreads out. This is pretty much the biggest challenge you can throw at it, so it's up to you if you really think you need 90 fps in this case. You could always turn some settings down when you know you are going to do a very demanding combination.

 

This is one thing I was going to add to this post later, you can copy the graphics settings xml file and just rename the one you are not using at that moment. Still some effort, but a lot less than clicking through all your settings