\section{Introduction}
\textbf{Disclaimer:} This is manual is currently a work in progress---please
bear with me while things are coming together.

\subsection{About Mitsuba}
Mitsuba is an extensible rendering framework written in portable C++. It implements unbiased 
as well as biased techniques and contains heavy optimizations targeted towards current CPU 
architectures.

In comparison to other open source renderers, Mitsuba places a strong emphasis on recent research-oriented 
rendering techniques, such as path-based formulations of Metropolis Light Transport and volumetric
modeling approaches.

\paragraph{Performance:}
One important goal of Mitsuba is to provide optimized implementations of the most commonly 
used rendering algorithms. By virtue of running on a shared foundation, comparisons between them can
better highlight the merits and limitations of different approaches. This is in contrast to, say, 
comparing two completely different rendering products, where technical information on the underlying 
implementation is often intentionally not provided.

\paragraph{Robustness:}
In many cases, physically-based rendering packages force the user to model scenes with the underlying 
algorithm (specifically: its convergence behavior) in mind. For instance, glass windows are routinely 
replaced with light portals, photons must be manually guided to the relevant parts of a scene, and 
interactions with complex materials are taboo, since they cannot be importance sampled exactly. 
One focus of Mitsuba will be to develop path-space light transport algorithms, which handle such 
cases more gracefully.

\paragraph{Scalability:} Mitsuba instances can be merged into large clusters, which transparently distribute and 
jointly execute tasks assigned to them using only node-to-node communcation. It has successfully
scaled to large-scale renderings that involved 1024 cores working on a single image.
Most algorithms in Mitsuba  are written using a generic parallelization layer, which can tap 
into this cluster-wide parallelism. The principle is that if any component of the renderer produces
work that takes longer than a second or so, it at least ought to use all of the processing power 
it can get.

The renderer also tries to be very conservative in its use of memory, which lets it handle 
large scenes (>30 million triangles) and multi-gigabyte heterogeneous volumes on consumer hardware.

\paragraph{Usability:}
Mitsuba comes with a graphical user interface to interactively explore scenes. Once a suitable 
viewpoint has been found, it is straightforward to perform renderings using any of the 
implemented rendering techniques, while tweaking their parameters to find the most suitable 
settings. Experimental integration into Blender 2.5 is also available.

\subsection{License}
Mitsuba is free software and can be redistributed and modified under the terms of the GNU General 
Public License (Version 3) as provided by the Free Software Foundation.


