Ray-Guided Volumetric Water Caustics in Single Scattering Media with DXR

This chapter presents a hybrid algorithm that uses ray tracing and rasterization to render surface and volumetric caustics in single scattering participating media. The algorithm makes use of ray tracing based on DirectX Raytracing (DXR) to generate data that drives hardware tessellation to adaptively refine triangular beam volumes that are rendered to slice volumetric caustics. Further on in the rendering pipeline, ray tracing is also used to generate secondary caustics maps that store the positions of ray/scene intersections for light rays that get reflected or refracted by a water surface.