X-Git-Url: https://git.ucc.asn.au/?p=ipdf%2Fsam.git;a=blobdiff_plain;f=chapters%2FProcess.tex;h=73e631d02232d78eaf77e821ece603555d0c6d4b;hp=a57d7e05a4c8feb23c9464975ecab0856007e29d;hb=67c33e185edd820e2ea6fef334455645bacd432b;hpb=9fcf44a0c34f393689118e913a2d17d907036c85

diff --git a/chapters/Process.tex b/chapters/Process.tex
index a57d7e0..73e631d 100644
--- a/chapters/Process.tex
+++ b/chapters/Process.tex
@@ -1,13 +1,124 @@
 \chapter{Methods and Design}
 
-\section{Softare Overview}
-\input{chapters/Process/SoftwareOverview}
-\section{Design Process}
-\input{chapters/Process/DesignProcess}
-\section{Coordinate Systems and Bounds Transformations}
-\input{chapters/Process/Transformations}
-\section{Measurements}
-\input{chapters/Process/Measurements}
+{\bf TODO} Write most of this section. I suspect I will have to be very selective about what to fit in considering the word limit.
 
+\section{Collaborative Process}
+\begin{itemize}
+	\item Collaborated with David Gow on the design and implementation of the SVG viewer
+	\item Individual work: Applying GMP Rationals (Sam), Quadtree (David)
+	\item Used git to collaborate \url{https://git.ucc.asn.au}
+	\item Used preprocessor defines to not interfere with each other's code too much
+	\item David used a \verb/goto/ letting the team down
+\end{itemize}
 
+\section{Structure of Software}
+\begin{itemize}
+	\item CPU and GPU renderer supported
+	\item Rendering of Cubic B\'{e}ziers (no antialiasing)
+	\item Partial implementation of shading Paths on CPU (abandoned)
+	\item Ability to move the view around the document with the mouse
+	\item Ability to insert an SVG into the view location
+	\item \verb/typedef/ for number representations
+	\item Ability to control program through scripts or stdio
+	\item Hacky python scripts to produce plots by abusing this
+\end{itemize}
+
+\section{Approaches to Arbitrary Precision}
+\begin{itemize}
+	\item Replace \emph{all} operations with arbitrary precision (ie: Rationals) - Horrendously slow
+	\item Change approach to applying coordinate transform \eqref{view-transformation}
+	\item Apply view transformations directly to objects as the view is transformed, rather than just before rendering
+	\begin{itemize}
+		\item Allows much better precision and range with just regular IEEE-754 floats
+		\item But there is an accumulated rounding error, particularly when zooming out and back in, which is bad
+	\end{itemize}
+	\item As above, but introduce intermediate coordinate system; use the Path elements
+	\begin{itemize}
+		\item Rendering of individual paths is consistent but overall they drift apart
+	\end{itemize}
+	\item As above, but specify Path coordinates with arbitrary precision rationals
+	\begin{itemize}
+		\item Works well, rationals slow down though
+	\end{itemize}
+\end{itemize}
+
+\section{Number Representations Trialed}
+\begin{itemize}
+	\item IEEE-754 single, double, extended
+	\item Custom implementation of Rationals with \verb/int64_t/
+	\begin{itemize}
+		\item Very limited since the integers grow exponentially and overflow
+	\end{itemize}
+	\item Custom implementation of Rationals with custom Arbitrary precision integers
+	\begin{itemize}
+		\item Actually works
+		\item Implementation of division is too slow to be feasible
+	\end{itemize}
+	\item Custom rationals but with GMP arbitrary precision integers
+	\begin{itemize}
+		\item Our implementation of GCD is not feasible
+	\end{itemize}
+	\item Paranoid Numbers; store a operation tree of IEEE-754 floats and simplify the tree wherever \verb/FE_INEXACT/ is \emph{not} raised
+	\begin{itemize}
+		\item This was a really, really, really, bad idea
+	\end{itemize}
+	\item Just use GMP rationals already
+	\begin{itemize}
+		\item Works
+	\end{itemize}
+	
+	\item MPFR floats
+	\begin{itemize}
+		\item They work, but they don't truly give arbitrary precision
+		\item Because you have to specify the maximum precision
+		\item However, this can be changed at runtime
+		\item Future work: Trial MPFR floats changing the precision as needed
+	\end{itemize}
+	
+\end{itemize}
+
+\section{Libraries Used}
+\begin{itemize}
+	\item SDL2 - Simple Direct media Library
+	\begin{itemize}
+		\item Used for window management and to obtain an OpenGL context
+		\item Also provides BMP handling which is useful
+	\end{itemize}
+	\item Qt4 (optional)
+	\begin{itemize}
+		\item Open source toolkit for Dialog based applications
+		\item We can optionally compile with a Qt4 based control panel
+		\item This is useful for interacting with the document
+		\item Has way more features than we actually use it for
+	\end{itemize}
+	\item OpenGL - Standard API for rendering on GPUs
+	\begin{itemize}
+		\item Using GLSL shaders
+		\item B\'{e}ziers are rendered using a Geometry shader which produces line segments
+	\end{itemize}
+	\item PugiXML - Open source XML parsing library
+	\begin{itemize}
+		\item Used to parse SVGs
+	\end{itemize}
+	\item GNU Multiple Precision (GMP)
+	\begin{itemize}
+		\item Implements arbitrary precision integers, floats, and rationals
+		\item We can use the arbitrary precision integers with a custom rational type
+		\item Or just use the GMP rational type (much better)
+		\item We don't use the floats, because they are hardware dependent
+	\end{itemize}
+	\item MPFR
+	\begin{itemize}
+		\item MPFR is built on GMP but ensures IEEE-754 consistent rounding behaviour
+		\item (Not hardware dependent)
+		\item We can compile with MPFR floats but the precision is currently fixed at compile time
+	\end{itemize}
+\end{itemize}
+
+
+\section{Design of Performance Tests}
+\begin{itemize}
+	\item This is mostly covered in the Results chapter
+	\item Control the program through stdin using a python script	
+\end{itemize}