Renderman Shading Language (abbreviated RSL) is a component of the

RenderMan Interface Specification The RenderMan Interface Specification, or RISpec in short, is an open API developed by Pixar Animation Studios to describe three-dimensional scenes and turn them into digital photorealistic images. It includes the RenderMan Shading Language. As ...

, and is used to define

shader In computer graphics, a shader is a computer program that calculates the appropriate levels of light, darkness, and color during the rendering of a 3D scene - a process known as ''shading''. Shaders have evolved to perform a variety of spec ...

s. The language syntax is C-like. A shader written in RSL can be used without changes on any RenderMan-compliant renderer, such as Pixar's

PhotoRealistic RenderMan Pixar RenderMan (formerly PhotoRealistic RenderMan) is proprietary photorealistic 3D rendering software produced by Pixar Animation Studios. Pixar uses RenderMan to render their in-house 3D animated movie productions and it is also available as ...

, DNA Research's

3Delight 3Delight, also known as 3DelightNSI, is 3D computer graphics software that runs on Microsoft Windows, MacOS and Linux. It is developed by Illumination Research. It is both a photorealistic and NPR path tracing offline renderer based on its NSI ...

, Sitexgraphics' Air or an open source solution such as

Pixie A pixie (also pisky, pixy, pixi, pizkie, and piskie in Cornwall and Devon, and pigsie or puggsy in the New Forest) is a mythical creature of British folklore. Pixies are considered to be particularly concentrated in the high moorland areas arou ...

Aqsis Aqsis is a free rendering suite compliant with the RenderMan standard. It is available under the BSD, previously under GPL. Its main author and project manager is Paul Gregory. The Aqsis project consists of a renderer, shader compiler and a ...

. RenderMan Shading Language defines standalone functions and five types of shaders: surface, light, volume, imager and displacement shaders. An example of a surface shader that defines a metal surface is: surface metal (float Ka = 1; float Ks = 1; float roughness = 0.1;) Shaders express their work by reading and writing special variables such as Cs (surface color), N (normal at given point), and Ci (final surface color). The arguments to the shaders are global parameters that are attached to objects of the model (so one metal shader can be used for different metals and so on). Shaders have no return values, but functions can be defined which take arguments and return a value. For example, the following function computes vector length using the

dot product In mathematics, the dot product or scalar productThe term ''scalar product'' means literally "product with a scalar as a result". It is also used sometimes for other symmetric bilinear forms, for example in a pseudo-Euclidean space. is an algebra ...

operator ".": float length (vector v)

External links

Shading Language (RSL) documentation
RenderMan Shading languages {{graphics-software-stub zh:RenderMan规范#RenderMan着色语言（RSL）

Further reading

External links