Tom's Hardware conducted an interview [tomshardware.com] with Palmer Luckey, the founder of Oculus VR. The defining takeaway? Virtual reality needs as much graphics resources as can be thrown at it:
Tom's Hardware: If there was one challenge in VR that you had to overcome that you really wish wasn't an issue, which would it be?
Palmer Luckey: Probably unlimited GPU horsepower. It is one of the issues in VR that cannot be solved at this time. We can make our hardware as good as we want, our optics as sharp as we can, but at the end of the day we are reliant on how many flops the GPU can push, how high a framerate can it push? Right now, to get 90 frames per second [the minimum target framerate for Oculus VR] and very low latencies we need heaps of power, and we need to bump the quality of the graphics way down.
If we had unlimited GPU horsepower in everybody's computer, that will make our lives very much easier. Of course, that's not something we can control, and it's a problem that will be solved in due time.
TH: Isn't it okay to deal with the limited power we have today, because we're still in the stepping stones of VR technology?
PL: It's not just about the graphics being simple. You can have lots of objects in the virtual environment, and it can still cripple the experience. Yes, we are able to make immersive games on VR with simpler graphics on this limited power, but the reality is that our ability to create what we are imagining is being limited by the limited GPU horsepower.
[...] The goal in the long run is not only to sell to people who buy game consoles, but also to people who buy mobile phones. You need to expand so that you can connect hundreds of millions of people to VR. It may not necessarily exist in the form of a phone dropping into a headset, but it will be mobile technologies -- mobile CPUs, mobile graphics cards, etc.
In the future, VR headsets are going to have all the render hardware on board, no longer being hardwired to a PC. A self-contained set of glasses is a whole other level of mainstream.
Using [pixels per degree (PPD)], AMD calculated the resolution required as part of the recipe for truly immersive virtual reality. There are two parts of the vision to consider: there's the part of human vision that we can see in 3D, and beyond that is our peripheral vision. AMD's calculations take into account only the 3D segment. For good measure, you'd expand it further to include peripheral vision. Horizontally, humans have a 120-degree range of 3D sight, with peripheral vision expanding 30 degrees further each way, totaling 200 degrees of vision. Vertically, we are able to perceive up to 135 degrees in 3D.
With those numbers, and the resolution of the fovea (the most sensitive part of the eye), AMD calculated the required resolution. The fovea sees at about 60 PPD, which combined with 120 degrees of horizontal vision and 135 degrees of vertical vision, and multiplying that by two (because of two eyes) tallies up to a total of 116 megapixels. Yes, you read that right: 116 megapixels. The closest resolution by today's numbers is 16K, or around  megapixels.
While 90 Hz (albeit with reduced frame stuttering and minimal latency) is considered a starting point for VR, AMD ultimately wants to reach 200 Hz. Compare that to commercially available 2560×1440 @ 144 Hz monitors or HDMI 2.0 [wikipedia.org] recently adding the ability to transport 3840×2160 @ 60 Hz. The 2016 consumer version of Oculus Rift [wikipedia.org] will use two 1080×1200 panels, for a resolution of 2160×1200 refreshed at 90 Hz. That's over 233 million pixels per second. 116 megapixels times 200 Hz is 23.2 billion pixels per second. It's interesting (but no surprise) that AMD's endgame target for VR would require almost exactly one hundred times the graphics performance of the GPU powering the Rift, which recommends an NVIDIA GTX 970 or AMD Radeon R9 290.
In conclusion, today's consumer VR might deliver an experience that feels novel and worth $300+ to people. It might not make them queasy due to the use of higher framerates and innovations like virtual noses [soylentnews.org]. But if you have the patience to wait for 15 years or so of early adopters to pay for stone/bronze age VR [soylentnews.org], you can achieve "absolute immersion," also known as enlightenment.