A Distributed, Decoupled System for Losslessly Streaming Dynamic Light Probes to Thin Clients

Abstract: We present a networked, high performance graphics system that combines dynamic, high quality, ray traced global illumination computed on a server with direct illumination and primary visibility computed on a client. This approach provides many of the image quality benefits of real-time ray tracing on low-power and legacy hardware, while maintaining a low latency response and mobile form factor. Our system distributes the graphic pipeline over a network by computing diffuse global illumination on a remote machine. Global illumination is computed using a recent irradiance volume representation combined with a novel, lossless, HEVC-based, hardware-accelerated encoding, and a perceptually-motivated update scheme. Our experimental implementation streams thousands of irradiance probes per second and requires less than 50 Mbps of throughput, reducing the consumed bandwidth by 99.4% when streaming at 60 Hz compared to traditional lossless texture compression. This bandwidth reduction allows higher quality and lower latency graphics than state-of-the-art remote rendering via video streaming. In addition, our split-rendering solution decouples remote computation from local rendering and so does not limit local display update rate or resolution.