RTSDF: Generating Signed Distance Fields in Real Time for Soft Shadow Rendering

Tan Yu Wei, Nicholas Chua, Clarence Koh, Anand Bhojan

Abstract: Signed Distance Fields (SDFs) for surface representation are commonly generated offline and subsequently loaded into interactive applications like games. Since they are not updated every frame, they only provide a rigid surface representation. While there are methods to generate them quickly on GPU, the efficiency of these approaches is limited at high resolutions. This paper showcases a novel technique that combines jump flooding and ray tracing to generate approximate SDFs in real-time for soft shadow approximation, achieving prominent shadow penumbras while maintaining interactive frame rates.