X-Plane looks phenomenal in VR over high res terrain with realistic weather. Here are some FPS tips to help get it working at its best.
- 1 X-Plane’s Good Points!
- 2 The Initial X-Plane VR Experience
- 3 How to Improve X-Plane FPS
- 4 X-Plane’s Vulkan Update
- 5 Review Your Hardware
- 6 Recommended X-Plane Add-Ons
- 7 Flightsim Hangar Contents List
- 8 Related Articles
X-Plane’s Good Points!
I’ve spent a lot of time dwelling on the problem areas of X-Plane so I need to remind myself what’s good about it too:
- It brings beautiful, realistic VR to the masses with a good physics model for a reasonable price
- It runs on multiple platforms
- It provides interfaces for 3rd Party support
- It provides a good balance of all the features a serious sim needs, including VR
- Vulkan & Metal support provides efficiencies in the rendering pipeline
The Initial X-Plane VR Experience
The first time into VR is an OMG experience but it takes time to choose the best graphical configuration settings. It drained my computer’s resources mercilessly. Initially, even with basic terrain I had to turn off clouds and shadows and have a moderate number of objects in order to get VR to work smoothly. Even with hardware upgrades in place the combination of settings I could pick remains a delicate balancing act.
How to Improve X-Plane FPS
Ensure nVidia Settings are Good
There are a couple of settings that will help with all games you are running. Right-click the desktop and open the nVidia panel. Select ‘Manage 3D Settings’.
- Power management mode = Prefer maximum performance
- Texture filtering quality = High performance
Reduce Background Processing
- Turn off real-time anti-virus processing
- Check your regular antivirus scan time
- Check your windows updater download times
Overclock your Graphics Card
If you haven’t already done this then you probably aren’t aware that you can overclock your graphics card by using MSI’s Afterburner.
Note: Overclocking my graphics card brought the GPU temperature down for X Plane but caused problems with the Microsoft Flight Simulator so I no longer use the overclocked settings.
MSI and YouTube will describe how to do it. The overclocking overview is like this:
- Install MSI’s Afterburner
- Set it to auto-start with Windows.
- Unlock voltage control and monitoring
- Open the Core Clock curve
- Open the OC scanner
- Begin a 4 point scan
- The scanner increases the frequency curve of the GPU to safe limits
- The new frequency power curve is saved with afterburner
- Manually save the new scan as a selectable profile
- Lock the voltage and control monitoring
- All done
Note that if you are intending to increase the graphics memory frequency as well, you should do that before the GPU overclocking so it can be incorporated into the final result.
I gained about 15% in terms of efficiency for no cash outlay. Each graphics card will react differently.
Tinker With Your X-Plane Settings
In the graphics settings panel the left hand side affects your GPU and the right hand panel affects your CPU. Choose your ‘must have’ settings first, and turn the other settings off. You can extend the rest when you have a satisfactory system.
Anti Aliasing Slider
With zero anti aliasing you will still see pixelisation in the Oculus Rift S. This is not removed by super-sampling using the ‘OVR Settings’ script (see below). However, adding the minimum value on this slider will take away the jagged edges on buildings etc. and reduce the shimmering effect caused by pixelisation.
Try These ‘Fly With LUA’ Scripts
LFD’s Auto View Distance Utility
Eventually I was drawn into filling in an omission in X Plane’s settings menu with this utility that optimises the graphics controls – you can find that here:
It responds dynamically to FPS drops as well. You should se an improvement.
‘OVR Settings’ Script
Anyone using X Plane in Oculus VR should at least try OVR Settings tool by Arnold Alting for Oculus Rift. It will provide you with an in-flight VR menu for super-sampling and ASW adjustments. This script has helped massively to improve the quality of the output.
Super-sampling renders the image onto a larger bitmap then reduces it to your display size. This is a simpler way to achieve anti-aliasing. It will give you a sharper instrument panel. It is less useful to the external view, but can only be applied globally and so will affect the FPS.
ASW is a prediction method for where you will be looking next. That will make your attachment to the VR world more solid. It also reduces the black bars on either side of your view when you turn quickly.
When flying close to complex scenery I would normally see visual stuttering when ASW is set to Auto. I discovered a significant additional quality improvement by limiting the frame rate to 27 FPS. The Near-scenery judder effect was drastically reduced and almost eliminated completely. Definitely worth a try. I would guess that holding the next frame draw until needed means that system is not redrawing old data and then missing the start of the next frame.
I used OVR Settings in conjunction with the Speedfan temperature chart to see how it was affecting my previous stressed out CPU. I also used it in conjunction with task manager to optimise my super-sampling selection in real time by monitoring the CPU and GPU usage as I altered the super-sampling factor.
Open Task Manager in windows, showing your CPU cores. The GPU usage is at the lower left. Use the ‘Move VR’ Script to display it in your cockpit.
- Fly to your worst case scenario i.e. high res terrain with lots of objects close to you
- Set your super-sampling factor
- Look outside then observe the usage in the GPU and CPU charts. My system works best with at least 80% GPU usage leaving 20% in reserve.
‘Fps boost + Auto LOD’ Script
I no longer use this script but it’s worth a mention.
If you open this LUA script up you will see 40+ property settings that give you significantly better frame rates due to the application of a bit of good sense. Well done to 1nnocent for figuring this stuff out and making it available to the community here.
This script is great if you are NOT using plugins that are manipulating visual effects. Amongst other things it changes the draw distance and LOD values. In VR this will make the sun and stars look like they are a few kilometres away, but you can edit it with a normal text editor to comment out the draw distance commands.
X-Plane’s Vulkan Update
Does the Vulkan Update Help?
I didn’t see a startling jump in performance, but I did see a solid 40 FPS for my usual settings in all situations except when looking into the far distance, and even then the lowest figure was about 36 FPS.
- I still have shimmer because this is to do with the Oculus Rift S resolution.
- My shimmer is reduced because I can apply 1.4 super-sampling throughout all scenarios without a problem.
- l still get some judder when looking at fast changing/moving terrain at short range. For example, when turning view quickly or flying low over buildings and looking directly down. This is worse over high res terrain, as expected.
- The limits to my settings haven’t changed but the FPS is now consistently at the 40 FPS maximum for an Oculus Rift S.
- The system handles a lot of cloud and no cloud equally well, which is excellent. A few months ago I couldn’t have clouds at all.
How Does Vulkan Contribute?
Vulkan provides a more direct access to the hardware level which reduces the time taken to execute tasks. This makes a difference when a particular operation is repeated millions of times. For X-Plane in particular:
- All of the shaders that will be used in a program are compiled and stored when the program is run for the first time. This can take several minutes. As the program runs, the precompiled shaders can be accessed as needed and the time to compile is removed from the frame rate.
- Textures required for a 3D scene must be preloaded. The programmers must predict which textures have to be made available to the video RAM ahead of time. Loading occurs on a separate thread.
- Video memory must be preloaded with required geometry. The programmer acquires a reference to a memory block and populates it ahead of time.
Vulkan’s frame rate efficiency is achieved by the use of its generic low level operations combined with tactical preloading of textures and geometry on separate threads. This combination eliminates or reduces stutter due to assets being loaded while efficient coding in the low level access to graphics hardware releases processing power in the form of increased FPS.
That’s all folks I hope this helped to point you in the right direction.
Review Your Hardware
This is probably the least useful thing to mention, but its part of the problem so needs to be taken into account.
X-Plane currently uses 3 cores, so if you’re not worried about MS Flight Simulator’s upcoming ability to use multiple cores you’ll want to get the fastest single core speeds you can afford (from Intel).
I used to have an i7 CPU which got uncomfortably close to the 100 C thermal limit quite often, and that would cause a nasty visual stutter. Here are the temperature traces provided by Speedfan.
The upper tangle of lines are the temperatures of the 4 CPU cores. The 70 C line is the temperature of a GTX 1070 Graphics card. A healthy temperature for a CPU when gaming is something in the range of 70 C to 80 C.
Note: Overclocking my graphics card brought the temperature down but also caused problems with the Microsoft Flight Simulator so I no longer use the overclocked setting.
A Note About My New Rig
In order to be ready for the Microsoft Flight Simulator I have bought a new rig containing a 16 core AMD 3950X. The multi-core CPU won’t help much with X-Plane (since it currently only uses 3 cores), however the speed of the system is higher in general and the frame-rate has been nearly doubled after careful tweaking of settings. When the X-Plane team released Vulkan my 40 FPS per eye became more consistent. However, I found it useful to limit the VR frame rate which reduced micro stutters.
Recommended X-Plane Add-Ons
Ultra Weather Plugin
A useful side effect of buying the Ultra Weather add-on seems to have been an improvement in the frame rate. I don’t have solid figures for that.
However I didn’t buy it for that, I bought it because I wanted a decent looking weather system. Now I fly through an epic living cloudscape with stupendous shadows cruising over the land, available globally. Shadows cast by the clouds on the terrain is always awesome and really makes the landscapes in VR very satisfying to see.
In addition it contains a slider for changing shadow resolution, which will increase the quality of the shadow edges in the cockpit considerably (but will be applied globally and affect the FPS).
- Realistic cloudscapes casting epic shadows
- Clouds become significant entities within the environment
- Control over cockpit shadow resolution
Western Alps Hi Res Terrain
For an extremely good VR experience you should add the Western Alps terrain by A Sky Story, and give them a donation. Whatever you give will be a tiny fraction of what it would cost to go there in person, and that’s exactly what it feels like. The vistas are beautiful and the changing time and weather refresh your perception of this beautiful area. Its amazingly realistic and feels like an mini holiday each and every time I visit.