Parallel Adaptive Frameless Rendering with NVIDIA OptiX

Abstract

In virtual reality (VR) or augmented reality (AR) systems, latency is one of the most important causes of simulator sickness. Latency is difficult to limit in traditional renderers, which sample time rigidly with a series of frames, each representing a single moment in time, depicted with a fixed amount of latency. Previous researchers proposed adaptive frameless rendering (AFR), which removes frames to sample space and time flexibly, and reduce latency. However, their prototype was neither parallel nor interactive. We implement AFR in NVIDIA OptiX, a concurrent, real–time ray tracing API taking advantage of NVIDIA GPUs, including their latest RTX ray tracing components. With proper tuning, our prototype prioritizes temporal detail when scenes are dynamic (producing rapidly updated, blurry imagery), and spatial detail when scenes are static (producing more slowly updated, sharp imagery). The result is parallel, interactive, low-latency imagery that should reduce simulator sickness.