The mystery has been solved.
Last November, Jonathan Blow posted a pair of cryptic images labeled "vr1" and "vr2" on the official website for his upcoming first-person exploration game The Witness. The only text — "What could it mean??" — offered no explanation.
He told Polygon at the time that he wanted "to support VR really well with this game — because The Witness is a game that is about exploring a space at your own speed, and walking around and looking at things, and not worrying about getting your face bitten off by a monster."
What he didn't tell anyone is what he was experimenting with — until today, when he solved the mystery he created late last year.
Blow was "pessimistic about VR systems in the near future," he wrote, in part because those he'd tried "didn't seem to offer much (certainly not enough to justify wearing a bulky headset all the time and fighting back feelings of nausea)." Things changed when he saw Valve's VR system, but that wasn't something he was allowed to talk about until recently.
"We worked with Valve to get support for the system in The Witness," he wrote, "and that's where those screenshots come from (but when I took the shots, an HMD was not plugged in, and as a result what you see is a dummy calibration that does not correspond to any useful image-warping; the screenshot was really more about just being happy about the [stereo] display capability.) In late November I spent a few days at Valve's offices working with Atman Binstock and Doug Church to adapt the HMD's input system more thoroughly for The Witness and to build a few scenes that are playable on the device."
Blow's experiments with Valve's device convinced him to add VR support to The Witness, which will make it debut first on PlayStation 4 this year.
"So, we will be supporting this device (and any similar devices) with The Witness," he wrote. "But I am really looking forward to see what gets designed specifically for devices like this."