# HG changeset patch
# User John Tsiombikas <nuclear@mutantstargoat.com>
# Date 1316647430 -10800
# Node ID 71a3eb026e80af8138dfcc31f4f74dd8356428a9
# Parent  0c1aab0534c577a128a23d0d9fa040626b2f497b
writing the scene file spec

diff -r 0c1aab0534c5 -r 71a3eb026e80 doc/scnfmt.tex
--- a/doc/scnfmt.tex	Thu Sep 22 01:19:37 2011 +0300
+++ b/doc/scnfmt.tex	Thu Sep 22 02:23:50 2011 +0300
@@ -1,16 +1,85 @@
-chunk
-------
-offs  size  description
-0     4     type id (four-cc)
-4     4     size (including header and children)
-8     sz-8  data (chunk specific)
+\documentclass[a4paper]{article}
 
-defined chunk ids
------------------
-root		"root"
-material	"mtl "
-object		"obj "
-camera		"cam "
+\title{ARDA \\
+\large \emph{a 3D scene file format for the calacirya renderer}}
+\author{}
+\date{}
 
-chunk description
------------------
+\begin{document}
+\maketitle
+
+\begin{abstract}
+Arda is a scene description format for the calacirya photorealistic renderer.
+It's a binary hierarchical chunk-based format, designed for simplicity and
+extensibility.
+\end{abstract}
+
+\tableofcontents
+\newpage
+
+\section{Overview}
+The ARDA file format is a hierarchical scene description for the
+\emph{calacirya} photorealistic renderer. The idea behind
+ARDA is to allow the core of the renderer to be completely oblivious about
+the file format beyond the root, and just prune subtrees and pass them to other
+modules for parsing. For instance, the core doesn't need to know anything about
+how triangle meshes are structured, it just cuts off that whole subtree and
+gives it to the mesh module for parsing.
+
+\section{Chunk layout}
+
+\begin{tabular}{ccl}
+offs 	& size	& description \\
+0		& 4		& type id (four-cc) \\
+4		& 4		& size (including header and children) \\
+8		& size - 8 & data (chunk specific)
+\end{tabular}
+
+%defined chunk ids
+%-----------------
+%root		"root"
+%material	"mtl "
+%object		"obj "
+%camera		"cam "
+
+\section{Chunks}
+
+A description of all predefined chunks follows.
+
+\subsection{Root}
+\begin{tabular}{rl}
+chunk id: & ``root'' \\
+data: & none \\
+children: & object (0 or more), material (0 or more), camera (0 or more)
+\end{tabular}
+
+This is the root node of the scene graph. Allowable children are any number of
+objects, materials, and cameras.
+
+\subsection{Material}
+\begin{tabular}{rl}
+chunk id: & ``mtl '' \\
+data: & none \\
+children: & name (1), shader (0 or 1), material attribute (0 or more).
+\end{tabular}
+
+\subsection{Material attribute}
+\begin{tabular}{rl}
+chunk id: & ``matr'' \\
+data: & none \\
+children: & name (1), vec3 (0 or 1), float (0 or 1), texture (0 or 1).
+\end{tabular}
+
+The material attribute carries its value as a vec3 or a float or both,
+modulated by a texture image.
+
+
+\subsection{Name}
+\begin{tabular}{rl}
+chunk id: & ``name'' \\
+data: & zero-terminated string of characters \\
+children: & none
+\end{tabular}
+
+
+\end{document}