Real-time discrete visibility fields for ray-traced dynamic scenes

Abstract

Environment lighting plays a crucial role in enhancing the realism of rendered images. As environment light sources are distributed over a sphere or hemisphere, the rendering process involves tracing multiple rays per pixel. This process is computationally expensive and therefore achieving real-time results is challenging. Many studies focus on visibility functions to reduce the number of traced rays, often achieved through precomputation methods. This study improves upon a recent CPU-based visibility precomputation method designed for rendering solely static scenes, enabling its use for dynamic scenes. Our key contribution is the parallelization of this algorithm across multiple compute shader invocations which well integrates into the modern real-time rendering pipeline. By analyzing the performance-quality impact of various parameters, we aim to discover the best configuration for a given scene. With our technique the entire preprocessing stage can be executed for a scene with more than $200K$ triangles in $4\mathrm{ms}$, allowing for more than a 50 FPS performance including precomputation and rendering.