Pixar’s Core Rendering Technology
For over twenty-five years RenderMan has been at the forefront of the visual effects revolution, and today RenderMan is a high performance renderer built to tackle the most complicated 3D imaginable. With the new state-of-the-art ray tracing RIS framework optimized for physically-based rendering combined with the efficiencies of the REYES architecture, RenderMan can deliver unmatched flexibility for any production pipeline.
Fast and Dependable
Pixar develops RenderMan for production, so every version is faster and more reliable than the previous one. Because Pixar uses RenderMan exclusively, the software has already been pushed to the extreme, so it’s ready to render anything you can throw at it.
RenderMan is fully multi-threaded and is happy to take advantage of machines with multiple cores. In the new RIS mode, RenderMan has extraordinary scalability on machines with many cores. Interactive rendering can benefit greatly because of this efficiency.
RenderMan’s motion blur and depth-of-field can mimic the behavior of real-world cameras, so RenderMan’s synthetic images can realistically simulate their conventionally filmed counterparts. RenderMan supports exotic camera effects like Bokeh and Shutter Speed.
Physically based Shading
Physically based Shading allows RenderMan to deliver highly realistic lighting with minimal setup, including full support for multi-bounce ray traced global illumination and ray traced subsurface scattering. Much research and development has gone into making these traditionally expensive effects a production reality. Pixar’s latest feature film, Monsters University, showcases this physically based system.
Fur and Hair
Fur and hair is essential for characters in animation and VFX, and RenderMan is capable of handling fur efficiently with a dedicated primitive, the riCurve. RenderMan can ray trace hair directly for single pass global illumination using the RIS framework, or hair can be rendered with REYES and use deep shadows and other cost effective techniques. The choice is yours.
Displacements have always been a strength of RenderMan and remain so today. With support for 32bit maps, ptex, and vector displacements, RenderMan can create highly complex displacements for any purpose.
Deep Textures have helped revolutionize compositing. In a deep texture each pixel contains all the samples in Z-space (making it “deep”), allowing edges to be filtered correctly with any composited elements, including traditionally problematic effects like depth of field. RenderMan is capable of generating deep textures, which can be used with a compatible compositor such as The Foundry’s Nuke.
RenderMan provides elegant methods for breaking visual effects down into secondary passes for compositing. With support for both AOVs and Light Path Expressions, RenderMan offers a multitude of ways of writing any element of a render (SSS, Diffuse, Shadows, Z-Depth, Object IDs, etc.) into many popular formats including OpenExr 2 and Deep Textures. Per-light AOVs are supported natively in RenderMan for Maya.
RenderMan Can Stand Alone
Call RenderMan as a simple executable and render any 3D data in RenderMan’s native RIB file format. These RIB files are the backbone of any RenderMan pipeline and are highly customizable, allowing many types of data to be converted to RIB and rendered with RenderMan. For example, NASA uses RenderMan for scientific visualization of extremely large datasets.
For serious animation and VFX, dispatching renders to a dedicated renderfarm is essential, and that system has to be robust and dependable. Pixar has developed Tractor specifically for this purpose as a modern system for remote job execution. Fast, efficient, and featuring a web dashboard, out-of-box RenderMan comes with Tractor, a great force multiplier for rendering.
The REYES Architecture
With the advent of the RIS framework, RenderMan is capable of amazing ray tracing feats, but note that the original REYES architecture is still available, right in the same software, for those times when the efficiencies of the REYES are a clear win. These different approaches to rendering CGI provide a large toolbox, providing the right tool for the job.