So the story goes: Palmer Luckey was working on the Oculus Rift headset's earliest prototypes from his parents' house. Luckey was a member of several forums dedicated to the world of 3D and, eventually, virtual reality. He was a part of the "mod" community, which is notorious for taking existing hardware and modifying it into something new — a portable Xbox 360, or a GameBoy that plays Super Nintendo games, for instance.
On the journey from ski-goggle prototype to something sellable, Carmack — an idol of Luckey's and, apparently, a member of the same VR forum — got in touch and asked to be sent a prototype. Wired catalogued the exchange in a 2014 story timed to publish soon after the Facebook acquisition:
"Carmack private-messaged him. Would Palmer consider sending him a loaner unit? Palmer, who idolized Carmack, shipped it off to Texas immediately — 'no NDAs, no signing anything,' Carmack says. 'It was one of two prototypes that he had.'
Carmack got to work on the machine, hot-gluing a motion sensor to it and duct-taping on a ski-goggle strap. But his greatest contribution came in the code he wrote for it. The Rift’s biggest selling point was its 90-degree field of view, which Luckey accomplished by slapping a cheap magnifying lens on the display. The problem was, that lens distorted the image underneath, making it warped and uneven. So Carmack coded a version of 'Doom 3' that pre-distorted the image, counteracting the effects of the magnifying lens and making the picture appear correct to the viewer. The result was a completely immersive gaming experience, the kind that would otherwise require $10,000 in high-end optics."