What is Asynchronous Spacewarp and why should you care?

With last week's release of the 1.10 runtime for the Oculus Rift platform, so too comes Asynchronous Spacewarp (ASW). This is not to be confused with the existing Asynchronous Timewarp (ATW) that was released earlier in the year. Let's take a look at what each technology does and how it affects you as a VR enthusiast.

What is Asynchronous Timewarp?

The skinny of ATW is this: when in the Rift, you're going to get a much smoother experience when it comes to positional head tracking. Your hardware can get distracted with other things than rendering frames of a Rift game, and ATW fills in when a frame can't be rendered in time.

Each eye gets a frame rendered for it.

For example, say that a frame is rendered for each eye. Everything works great and the image is clear. Your CPU and GPU must then work on rendering the next frame, but get distracted working on something else. The left eye's frame is complete, but the right eye's frame is not. ATW will take the previous frame from the right eye, re-align it to correspond with how your head is now oriented, and show it on the display.

The result? A smooth picture that reduces motion sickness and gives an overall better VR experience. Oculus claims that ATW contributes up to about 100 times less judder in games.

Asynchronous Timewarp is not a crutch that can be used by lazy developers who do not want to optimize their games for 90FPS. It is more of a failsafe for when your PC decides it has something better to do than render frames. Any Oculus experience that doesn't efficiently meet 90FPS without ATW will suffer from a poor image and you will experience positional judder.

Asynchronous Spacewarp

It's best to think of ATW and ASW as best friends on a mission to make your time in Rift as enjoyable as possible. While ATW works at keeping positional judder to a minimum, ASW works at keeping pretty much all other sources of jerky motion to a minimum.

Your player's movement and any camera movement are taken into consideration and, if the game drops below a suitable frame rate, ASW kicks in to produce 'fake' frames that fill in. The result is an all-around smooth experience. Now, with the introduction of room-scale tracking, ASW will cover Touch controller movement and your physical movement around your VR space. You can see why ATW no longer cuts it on its own.

Using Touch controllers.

Like Asynchronous Timewarp, Asynchronous Spacewarp is enabled automatically any time your PC needs it. There's nothing you have to turn on; just play, and see if you notice when it kicks in. Those of you with beefy gaming PCs probably won't notice it at all, but anyone with a PC just scraping the minimum requirements will likely see it in action quite a bit.

Again, ASW is not a crutch that developers can lean on. It does, however, make up for PC hardware that can't normally reach 90FPS, significantly lowering the minimum system requirements.

New minimum system requirements

Thanks to ASW now working in tandem with ATW, minimum system requirements for the Rift have dropped.

Hardware Old system reqs New minimum system reqs
GPU NVIDIA GTX 970 / AMD Radeon R9 290 NVIDIA GTX 960 / AMD Radeon RX 470
CPU Intel i5-4590 Intel i3-6100 / AMD FX4350

This drop in hardware has opened up a completely new field of PCs that are ready for VR, and more people are now finding a top-notch virtual reality experience to be affordable.

Not sure if your PC can run an Oculus Rift? Oculus has a great compatibility tool you can download and run to automatically test your PC.

Click to download the Oculus Rift compatiblity tool

If you've run the Rift compatibility tool and everything checks out but you're still experiencing poor performance, have a look at our guide on getting the best performance out of your PC.

How to ensure the best VR performance from your PC

You and ASW

Have you noticed ASW or ATW kick in while you're within your Rift? What was your experience like? Let us know in the comments section below!