Brian Koponen

Programming and Tech Tips

How To Run DiRT 4 in VR Using VorpX

DiRT 4, sadly, does not have native support for virtual reality like the Dirt Rally games. Racing games work so well in VR, I always try to find a way to play them in VR with either a mod or, most often, by using VorpX. The results can be mixed, everything from barely working to nearly native-level VR.

DiRT 4 works reasonably well in VR using VorpX. You are limited to playing in Immersive Screen Mode, which displays the game in full 3D on a giant virtual screen. You can't look around the cockpit in this mode, so you don't feel nearly as immersed as you do in a native VR title like Dirt Rally. That said, the game is in perfect 3D, which is the most important thing. The FOV of the camera is wide enough and the screen big enough that you quickly forget about the limitations when you are actually driving the car.

The main problem most people will have is with performance. The game is not optimized for VR and you need a very high performance PC to be able to run this at 90fps at high settings. Seeing how bad the performance is shines light as to why they didn't include native VR support at all. Obviously the rendering pipeline they used for this game would need substantial reworking to support VR.

With tempered expectations, let's look at what you need to make this work and how to overcome some odd issues that can crop up.


What You Will Need

VorpX - $40

VorpX is the program that can make a traditional 2D game render in stereoscopic 3D in a VR headset. DiRT 4 is fully supported by VorpX, so you don't need to do anything to make it work. I know VorpX has a mixed reputation, but if you are interested at all in playing older games in VR, especially racing games, it's an incredible tool. You can read my overall thoughts on the program here.

To play DiRT 4 in VR, all you have to do is start VorpX and then launch DiRT 4. The built-in profile works perfectly, so you don't need to make any VorpX adjustments.


DiRT 4 Settings

In DiRT 4, there are a few settings that you need to adjust to work in VR properly.

Field of View

In Options & Extras > Game Preferences:

Setting Value
Camera Field of View Widest Setting (all the way to the right)
Camera Shake No Shake (all the way to the left)
Cockpit Driver and Wheel Wheel Only (if playing with a wheel)

With the FOV set to its widest setting, the scale of the world looks perfect. I turn off the Camera Shake as there is plenty of camera motion in VR as it is. If you are playing with a wheel (which I highly recommend), by displaying only the cockpit wheel, the wheel animation will properly line up with your actual wheel's rotation.


Clutch Input Problem

In Options & Extras > Input > Device Management > Keyboard > Input Bindings:

Unbind the Clutch pedal input.

A weird issue can arise involving the clutch. Oftentimes the car won't move off the starting line, even though all the inputs are working. At first I thought this was some bizarre physics problem, but it is actually very simple. Somehow the game thinks the 'c' key is being held down, which is the clutch pedal on the keyboard input and as long as the clutch is held down, the car won't move.

By unbinding the clutch input from the Keyboard input, the problem disappears.


Mouse Cursor Visible

VorpX has its own mouse cursor that displays in the menus. For most games, this cursor disappears normally once you are in the main game. For some reason, this does not happen in DiRT 4.

Be aware that you can hide the VorpX mouse cursor, in any game, by pressing Alt-C.


Performance

As a point of reference, on a desktop machine with an i7 8700 and GTX 1070, I have to set the graphics to nearly the Ultra Low preset in order to get a consistent, playable framerate with Geometry 3D mode enabled. At that setting, the game looks pretty bad. That said, I still prefer playing the game in 3D, even if the graphics look quite basic.

This is, by far, the biggest problem trying to play DiRT 4 in VR. If you want to have better graphics, or have a machine with lower specs than mine, you will have to switch from Geometry 3D to Z-Normal mode. To my eye, this complete removes the 3D effect. I couldn't see a difference between turning the 3D mode off and Z-Normal.

Of course, if you have a more powerful computer, and as time goes on more people certainly will, you can increase the graphics quality much higher and the game will look very nice in 3D.


Experience

As for the rest of the experience, the game works very well in VR. The menus appear at a good distance, so you can navigate and read everything very easily. You would almost think the menus were designed for VR it works so well.

While it would be nice, of course, for the game to be supported as a Full VR title in VorpX, it actually doesn't affect the gameplay very much at all to play in Immersive Screen Mode. When you are focused on the road ahead of you, it doesn't make a big difference that you can't look around very much.

I have noticed that there can be problems with certain textures. The car texture can turn black, which doesn't affect the gameplay, but looks quite odd in the cutscenes. Similarly, the textures or lighting in the cockpit isn't quite right, but this, again, is a fairly small cosmetic detail. Importantly, the actual track graphics are unaffected by any of this.


Better than non-VR?

Whenever I play a game in VR using VorpX, I like to ask if the game actually improves in any way by doing so, or is it more of an interesting experiment without any real benefits.

DiRT 4 is an interesting case, making this a more difficult question than in some other games. Generally, in any racing game, having the depth perception provided by VR is a great advantage and that is certainly true of DiRT 4. In this case, though, if you don't have the hardware to keep up a high framerate, the game becomes nearly unplayable.

While the graphical downgrade doesn't actually impact gameplay, it certainly hurts the overall experience. If you are willing to make that sacrifice or have the hardware so you don't need to, then playing in VR makes the gameplay fundamentally better than playing in 2D.


Conclusion

Playing a racing game in VR really breathes new life into it. DiRT 4 was certainly not my favorite of the series, but playing in VR has made me appreciate it in a whole new way. I highly recommend trying this out if you have the hardware to run it.

Let me know if you have any comments or questions.

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