CloVR: Fast-Startup Low-Latency Cloud VR

VR headsets have limited rendering capability, which limits the size and detail of the virtual environment (VE) that can be used in VR applications. One solution is cloud VR, where the "thin" VR clients are assisted by a server. This paper describes Cio VR, a cloud VR system that provides fast loading times, as needed to let users see and interact with the VE quickly at session startup or after teleportation. The server reduces the original VE to a compact representation through near-far partitioning. The server renders the far region to an environment map which it sends to the client together with the near region geometry, from which the client renders quality frames locally, with low latency. The near region starts out small and grows progressively, with strict visual continuity, minimizing startup time. The low-latency and fast-startup advantages of CloVR have been validated in a user study where groups of 8 participants wearing all-in-one VR headsets (Quest 2's) were supported by a laptop server to run a collaborative VR application with a 25 million triangle VE.