...

A RixPattern plugin is used to connect textures and procedurally generated patterns to RiBxdf parameters, or to other patterns to create a shading graph. There are numerous pattern plugins included with the RenderMan software, but if none of the included plugins generate the pattern you want, then this guide will help you write your own pattern plugin. Source code for many of the RenderMan pattern plugins can be found in the PixarRenderMan-Examples-VERSION/plugins/pattern/ directory which is installed as part of the separate examples package.

...