Arnold Render Cinema4D User Guide – E-BOOK

Arnold Render Cinema4D User Guide – E-BOOK

Arnold is an advanced cross-platform rendering library, or API, developed by Solid Angle and used by a
number of prominent organizations in film, television and animation, including Sony Pictures Imageworks.
It was developed as a photo-realistic, physically-based ray tracing alternative to traditional scanline based
rendering software for CG animation.
Arnold uses cutting-edge algorithms that make the most effective use of your computer’s hardware
resources: memory, disk space, multiple processor cores, and SIMD/SSE units.
The Arnold architecture was designed to easily adapt to existing pipelines. It is built on top of a pluggable
node system; users can extend and customize the system by writing new shaders, cameras, filters and
output driver nodes, as well as procedural geometry, custom ray types and user-defined geometric data.
The primary goal of the Arnold architecture is to provide a complete solution as a primary renderer for
animation and visual effects. However, Arnold can also be used as:
 a ray server for traditional scanline renderers
 a tool for baking/procedural generation of lighting data (lightmaps for videogames)
 an interactive rendering and relighting tool
Why is Arnold different?
Arnold is a highly optimized, unbiased, physically-based ‘Monte Carlo’ ray / path tracing engine. It doesn’t
use caching algorithms that introduce artifacts like photon mapping and final gather. It is designed to
efficiently render the increasingly complex images demanded by animation and visual effects facilities
while simplifying the pipeline, infrastructure requirements and user experience.
Arnold provides interactive feedback, often avoiding the need for many render passes and allowing you to
match on-set lighting more efficiently. By removing many of the frustrating elements of other renderers,
Arnold fits better with your work-flow, produces beautiful, predictable and bias-free results, and puts the
fun back into rendering!
What is wrong with algorithms like photon mapping or final gather?
Such algorithms attempt to cache data that can be re-sampled later, to speed up rendering. However in
doing so, they use up large amounts of memory, introduce bias into the sampling that cause visual
artifacts. They also require artists to understand the details of how these algorithms work in order to
correctly choose various control settings in order to get any speed up at all without ruining the render.
Worse than that, these settings are almost always affected by other things in the scene, so it’s often
possible to accidentally use settings for the cache creation / use that make things worse, not better, or
that work fine in one situation but are terrible in another, seemingly similar, situation.
In short, they are not predictable, other than for very experienced users, and require artists to learn way
too much about the algorithms in order to gain any benefit. At Solid Angle, we believe that your time is
more valuable than your computer’s time; why spend an extra 30 minutes working with photon mapping
or final gather settings, even if it saves 30 minutes render time (and more often than not it doesn’t).
That’s still 30 minutes not spent modeling, animating or lighting.