Arvid Schneider shows how to write a probability shader using the Arnold OSL Shader.
Like all high-end render engines, Arnold offers artists the flexibility of using OSL shaders. OSL or Open Shading Language is an open-source language specification, compiler, and runtime library by initially by Sony Pictures Imageworks. It allows artists and technical directors to script custom shading tools. Under the context of Arnold Render, there is an OSL Ai node you can use to run OSL shaders or to create your own.
With Arvid Schneider’s latest tutorial, the Lighting TD for ILM shows how you can write a probability shader using the Arnold OSL Shader. Arvid notes that the process is relatively straight forward but also notes that learning how to create custom shaders with OSL offers a lot of rewards.