\section{Introduction}
At the present time, \RAY\ and its scene description grammar are extremely 
primitive, this will be remedied as time passes.  For now I'm going to 
skip the "Intro to Raytracing" and related things that should probably 
go here, I'll put them in later.  This document is currently designed 
to serve the needs of sophisticated users.  If you have suggestions, I'll 
be glad to get to them. 

Until this document is finished, the best way to learn how \RAY\
works is to examine some of the sample scenes that I've included
in the \RAY\ distribution.  Although they are all very simple, each of 
the scenes tries to show something slightly different \RAY can do.
Since \RAY\ is rapidly changing to accomodate new rendering primitives and
speed optimizations, the scene description language is likely to change 
to some degree as well.  The scene desciption language used is extremely 
simple.  

\subsection{\RAY\ Feature List}
  Although \RAY\ is a relatively simple renderer, it does have enough 
features that they bear some discussion.

\begin{itemize}
\item Parallel execution using MPI.
\item Parallel execution using POSIX or Unix-International 
      threads libraries.
\item Automatic grid-based spatial decomposition scheme for greatly
      increased rendering speeds.
\item Simple antialiasing based on psuedo-random supersampling
\item Provides many useful geometric objects including 
      Spheres, Planes, Triangles, Cylinders, Quadrics, and Rings
\item Texture mapping
\item Supports rendering of volumetric data sets 
\end{itemize}


