Open Shading Language (OSL) is a small but rich language for programmable shading in advanced renderers and other applications, ideal for describing materials, lights, displacement, and pattern generation. OSL was originally developed by Sony Pictures Imageworks for use in its in- house renderer used for feature film animation and visual effects, released as open source so it could be used by other visual effects and animation studios and rendering software vendors. Now it's the de facto standard shading language for VFX and animated features, used across the industry in many commercial and studio- proprietary renderers. Cuda and OptIx are optional dependencies but they are not tested. OSL is an optional dependency for Blender. Warning for Slackware current users: since the current's LLVM is updated to version 17, this version of OSL cannot be built on Slackware current because versions of LLVM greater than 15 are out of range.