Three of the most talked-about virtual reality headsets – the Oculus Rift , HTC Vive , and PlayStation VR – are less than a year old, but if you stopped by the Game Developers Conference in San Francisco this week you’d be forgiven for concluding that they were as obsolete as an Apple eMac . That’s because much of the buzz at this year’s GDC, an annual hobnob of bigwigs from the gaming and consumer tech industries, was about augmented reality glasses and standalone VR headsets – the kind that require neither a PC nor a smartphone to run.