Arnold does not support Caustics like other render eninges do. Go with Corona or Maxwell if you need the real stuff. Or do a search for fake caustics in Arnold.
Hello! I'm on a task to generate a lightmap for faking car's headlights output using Arnold for 3dsMax 2020 along with render to texture. So far I managed to obtain the "pure" light projection, and I'd like to add on top a caustic effect using the glass lens in front of the light sources that are mesh emitters (can't use…