X-Git-Url: https://git.ucc.asn.au/?p=ipdf%2Fdocuments.git;a=blobdiff_plain;f=LiteratureNotes.tex;h=c7aae7b3ef3f0d4f1bdc4581b7ed04a57586bff2;hp=a9292dc31dc6eb45fcd034c6c7678fd14116a9bd;hb=12e7dacee2405e1edae91fc2c78437dcaa4181f5;hpb=f1069d4e2ac6473ff167bb7385f22b446a91b2dc diff --git a/LiteratureNotes.tex b/LiteratureNotes.tex index a9292dc..c7aae7b 100644 --- a/LiteratureNotes.tex +++ b/LiteratureNotes.tex @@ -18,7 +18,7 @@ \parskip 8.2pt % sets spacing between paragraphs %\renewcommand{\baselinestretch}{1.5} % Uncomment for 1.5 spacing between lines \parindent 0pt % sets leading space for paragraphs -\linespread{0.8} +\linespread{1} \newcommand{\vect}[1]{\boldsymbol{#1}} % Draw a vector @@ -37,14 +37,14 @@ \definecolor{darkred}{rgb}{0.75,0,0} \definecolor{darkblue}{rgb}{0,0,0.75} \definecolor{pink}{rgb}{1,0.5,0.5} -\lstset{language=Java} +\lstset{language=XML} \lstset{backgroundcolor=\color{darkgray}} -\lstset{numbers=left, numberstyle=\tiny, stepnumber=1, numbersep=5pt} -\lstset{keywordstyle=\color{darkred}\bfseries} -\lstset{commentstyle=\color{darkblue}} +%\lstset{numbers=left, numberstyle=\tiny, stepnumber=1, numbersep=5pt} +%\lstset{keywordstyle=\color{darkred}\bfseries} +%\lstset{commentstyle=\color{darkblue}} %\lstset{stringsyle=\color{red}} -\lstset{showstringspaces=false} -\lstset{basicstyle=\small} +%\lstset{showstringspaces=false} +%\lstset{basicstyle=\small} \newcommand{\shell}[1]{\texttt{#1}} \newcommand{\code}[1]{\texttt{#1}} @@ -615,9 +615,100 @@ IE: The more precise the representation, the slower things go wrong, but they st This is an example where the calculation of a function $f(a,b)$ is not only totally wrong, it gives completely different results depending on the CPU. Despite the CPU conforming to IEEE. +\section{Scalable Vector Graphics (SVG) 1.1 (Second Edition) \cite{svg2011-1.1}} + +Scalable Vector Graphics (SVG) is a XML language for describing two dimensional graphics. This document is \url{http://www.w3.org/TR/2011/REC-SVG11-20110816/}, the latest version of the standard at the time of writing. + +\subsubsection{Three types of object} +\begin{enumerate} + \item Vector graphics shapes (paths) + \item Images (embedded bitmaps) + \item Text +\end{enumerate} + +\subsubsection{Rendering Model and Precision} + +SVG uses the ``painter's model''. Paint is applied to regions of the page in an order, covering the paint below it according to rules for alpha blending. + +``Implementations of SVG are expected to behave as though they implement a rendering (or imaging) model cor- +responding to the one described in this chapter. A real implementation is not required to implement the model in +this way, but the result on any device supported by the implementation shall match that described by this model.'' + +SVG uses {\bf single precision floats}. Unlike PDF and PostScript, the standard specifies this as a {\bf minimum} range from \verb/-3.4e+38F/ to \verb/+3.4e+38F/ + +``It is recommended that higher precision floating point storage and computation be performed on operations +such as coordinate system transformations to provide the best possible precision and to prevent round-off errors.'' + +There is also a ``High Quality SVG Viewers'' requirement to use at least {\bf double} precision floats. + +\section{OpenVG Specification 1.1 \cite{rice2008openvg}} +``OpenVG is an application programming interface (API) for hardware-accelerated two- +dimensional vector and raster graphics developed under the auspices of the Khronos +Group \url{www.khronos.org}.'' + +Specifically, provides the same drawing functionality required by a high-performance SVG document viewer (SVG Tiny 1.2) +TODO: Look at that $\neq$ SVG 1.1 + +It is designed to be similar to OpenGL. + +\subsubsection{Precision} +``All floating-point values are specified in standard IEEE 754 format. However, +implementations may clamp extremely large or small values to a restricted +range, and internal processing may be performed with lesser precision. At least +16 bits of mantissa, 6 bits of exponent, and a sign bit must be present, allowing +values from $\pm 2^{-30}$ to $\pm2^{31}$ to be represented with a fractional precision of at least 1 +in $2^{16}$.'' + +IEEE but with a non standard number of bits. + +Presumably the decreased precision is for increased efficiency the standard states that example applications are for ebooks. + + +\section{Document Object Model --- pugixml 1.4 manual \cite{pugixmlDOM}} + +Pugixml is a C++ library for parsing XML documents\cite{kapoulkine2014pugixml}. XML is based on the Document Object Model (DOM); this is explained pretty well by the pugixml manual. + +The document is the root node of the tree. Each child node has a type. These may +\begin{itemize} + \item Have attributes + \item Have child nodes of their own + \item Contain data +\end{itemize} + +In the case of HTML/SVG an XML parser within the browser/viewer creates the DOM tree from the XML (plain text) and then interprets that tree to produce the objects that will be rendered. + +Example of XML $\to$ DOM tree given at\cite{pugixmlDOM}. +Example of XML parsing using pugixml is in \shell{code/src/tests/xml.cpp} + + +\begin{figure}[H] + \centering +\begin{lstlisting}[language=XML,basicstyle=\ttfamily] + + + + some text + + some more text + + + + + + +\end{lstlisting} + + \includegraphics[width=0.6\textwidth]{references/pugixmlDOM-dom_tree.png} + \caption{Tree representation of the above listing \cite{pugixmlDOM}} +\end{figure} + \chapter{General Notes} -\section{Floating-Point \cite{HFP,goldberg1991whatevery,goldberg1992thedesign,priest1991algorithms}} +\section{The DOM Model} + +A document is modelled as a tree. The root of the tree is the document. This has nodes of varying types. Some nodes may have children, attributes, and data. + +\section{Floating-Point Numbers\cite{HFP,goldberg1991whatevery,goldberg1992thedesign,priest1991algorithms}} A set of FP numbers is characterised by: \begin{enumerate}