Microsoft has been pushing the idea of mixed reality -- combining virtual and augmented reality -- for years now. But today at Oculus Connect 5, Facebook showed off a concept that pushes the notion of mixed reality even further. We caught a brief glimpse of Andrew Bosworth, the company's head of AR and VR, wearing an upcoming Oculus Quest headset. Instead of seeing an artificial VR environment, he saw a crude real-time rendering of the room around him, drawn in a cartoon-like style. As he panned his head around, the layout and furniture in the room appeared, as if it were being painted in place.