A natural evolution.
Epic has revealed a nifty new feature coming to Unreal Engine 4 later this year. The new addition is VR-focused, designed specifically for developers creating VR games.
The engine's level editor itself be used with VR. So a developer would be wearing a VR headset and using VR controllers to create in real-time. Epic describes it as a "virtual iPad" interface, and says it works with both Vive and Rift controllers.
Watch Epic Games' Tim Sweeney and Mike Fricker show it off using Valve and HTC's Vive headset, including the wands.
More details will be revealed at GDC in March. For now, you can still watch an archive of a recent livestream, where the tech was unveiled.