Yesterday, Sony Pictures Imageworks -the award-winning visual effects and digital character animation unit of Sony Pictures Digital Productions- released the Alpha version of its source code for OSL (Open Shading Language).
What is OSL?
Open Shading Language (OSL) is a small but rich language for programmable shading in advanced renderers and other applications. OSL is similar to C, as well as other shading languages; however, it is specifically designed for advanced rendering algorithms with features such as radiance closures, BRDFs, and deferred ray tracing as first-class concepts.
The OSL project includes a complete language specification, a compiler from OSL to an intermediate assembly-like bytecode, an interpreter that executes OSL shaders on collections of points in a SIMD manner, and extensive standard shader function library. These all exist as libraries with straightforward C++ APIs, and so may be easily integrated into existing renderers, compositing packages, image processing tools, or other applications. Additionally, the source code can be easily customized to allow for renderer-specific extensions or alterations, or custom back-ends to translate to GPUs or other special hardware. (source)
For more information on the project and the alpha release of the source code, check out code.google.com.
The bigger picture...
OSL's release is part of Sony Pictures Imageworks' open source initiative, announced in June 2009 - at last year's SIGGRAPH in New Orleans. Within this initiative, five technologies would be released initially: Maya Reticle (flexible camera guides for Maya), Pystring (Python string handling in C++), Field3D (a voxel data storage library), Scala Migrations (a database library manager), and the forementioned OSL (Open Shading Language). Check out opensource.imageworks.com for more information.