Faking Caustics in Maya (Dirt Cheap)

This was the way I faked the caustics on the sunflower pill project in school. This is many years old and about the only way I could get it done with the hardware back then. It is a really fast and cheap way to fake it…

Connect a samplerInfo node’s facing ratio into a ramp’s vChoord. The outColor of the ramp is then fed into the transparency attribute of the shader.

This allows you to overdrive the transparency and where the object/objects is/are facing the light (top of the V ramp) and totally dial in the way you want your caustics to look. You have to raytrace your shadows to get this effect to work because the technique is based on the fact that raytracing takes transparency into account when computing shadows.

I had a duplicate set of pills that had “primary visibility”, “visible in reflections”, and “visible in refractions off and “cast shadows” on, so their only function was to cast the caustic shadows.