
Caustics are everywhere. Defined as concentrations of light refracted or reflected off a specular surface, common examples include the patterns you see on the bottom of a pool and the bright curves of light in a wine glass’s shadow. But they also affect the way you see through windows and the reflections cast by any shiny surface. Turning on caustics in ray-traced renders can add subtle levels of realism, but their high computational expense means they are usually omitted.
That is until now. The latest release of the Corona Renderer includes a vastly improved caustics solver — which minimizes resource-intensive overheads. In this podcast, Corona’s Founding Partner and Main Developer Ondřej Karlik, and R&D Partner Jaroslav Křivánek tell Chris why caustics are so hard to compute. They also discuss the approach they took to make them work, their vision for the future of caustics — and whether the new solver will make its way to V-Ray.

Chris is a CG industry veteran and Director of Chaos Labs. He can also be heard regularly as the host of the CG Garage podcast which attracts 20,000 weekly listeners. With a background in both VFX and Design, Chris has worked for Gensler, Digital Domain, Imageworks and Method Studios. His credits include Maleficent, Oblivion and Tron: Legacy.