Caustic reflection and refraction


As compared to Cycles within blender, the Cycles render within Rhino WIP is not able to generate Caustic reflection and refraction. I have tried the no_caustic option. But that only affects the transmission. Is there a way to enable those features.

(Nathan 'jesterKing' Letwory) #2

Setting the no_caustics option to true will cause both caustics_reflective and caustics_refractive to be false. With no_caustics set to false those two will be true. These are the low-level Cycles integrator settings.

What you are seeing is that most likely multiple importance sampling isn’t on for everything. That is necessary for the caustics to work.

I have created RH-40088 to track this.

(Nathan 'jesterKing' Letwory) #3

@rajeev - can you double-check? There have been many changes since, and while I haven’t specifically worked on this I did enable MIS and made changes related to the caustics that Cycles does support.

Thanks in advance,



the tracker is non public

(Nathan 'jesterKing' Letwory) #5

't Is no longer thus.


Can the cycle’s renderer do refraction/dispersion, as in gem sparklie colors?

(Nathan 'jesterKing' Letwory) #7

Unfortunately no. This can be faked by some degree by setting up a glass that has three different glass BSDFs, one for red, one for blue, one for green, each with a different IOR, but not with the existing materials. It’ll need a special material.

Here is an example of a material specifically build for dispersion effects. Not perfect, but it means I could recreate something similar for Raytraced: