I didn't say anything could or could not be done with Cycles. I said there were 'tons of RSL examples'. Do you understand the significance of a history, and body of work available to start with, and not having to start from scratch? I was using BMRT in the 90s, and reading books about procedurally-generated textures. People wrote so many shaders in RSL, most available for you to copy, modify and re-use. I am assuming there are not nearly as many OSL examples as RSL examples or samples of code. I may be wrong. For the record, I'll use both, and I am happy to see Renderman as an option. I am particularly interested in OSL as a corollary to RSL. Sony used it successfully to counter Pixar's mention here. I am also eager to test my RSL chops again too!
Most of those shaders written back then are pretty much worthless now that Renderman has introduced RIS mode (instead of REYES mode), which was introduced last year. Pixar recommends writing shaders in C++ now instead of in RSL, as C++ shaders are just way more performant right now. OSL is pretty mature, I know that both Sony Pictures Imageworks and Double Negative use it in production. Now that Renderman also support OSL I'm pretty sure we're going to see OSL examples posted online. OSL shaders are awesome compared to RSL shaders, as OSL gives all control to the renderer, which allows it to do a lot of optimization (such as using the renderers own importance sampling strategies).
Thanks, I'll have to look even more into OSL (vs. GSL or RSL). I would hardly use the word 'worthless' just because RIS mode was introduced last year. The basics of what the prodecurally generated textures book taught me back then, still apply. Geometry, math, building up patterns in software, etc... Not to mention, the basis of such shaders just need to be translated just as GSL can be relatively simple to translate into OSL as the videos by Thomas Dinges show: https://www.youtube.com/watch?v=4LQXjIDWtz0
