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

TL;DR

This paper introduces a real-time method combining jump flooding and ray tracing to generate approximate signed distance fields for soft shadow rendering, enabling dynamic surface updates and high-quality shadows in interactive applications.

Contribution

It presents a novel GPU-based technique that efficiently generates approximate SDFs in real-time, improving soft shadow quality without sacrificing performance.

Findings

Achieves real-time SDF generation at high resolutions

Produces prominent shadow penumbras in interactive frame rates

Combines jump flooding with ray tracing for efficient approximation

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.