\let\mypdfximage\pdfximage\def\pdfximage{\immediate\mypdfximage}\documentclass[twoside]{book}

% Packages required by doxygen
\usepackage{fixltx2e}
\usepackage{calc}
\usepackage{doxygen}
\usepackage{graphicx}
\usepackage[utf8]{inputenc}
\usepackage{makeidx}
\usepackage{multicol}
\usepackage{multirow}
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\usepackage[nointegrals]{wasysym}
\usepackage[table]{xcolor}
\usepackage{ifpdf,ifxetex}

% Font selection
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\usepackage{amssymb}
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\newcommand{\+}{\discretionary{\mbox{\scriptsize$\hookleftarrow$}}{}{}}

% Arguments of doxygenemoji:
% 1) ':<text>:' form of the emoji, already "LaTeX"-escaped
% 2) file with the name of the emoji without the .png extension
% in case image exist use this otherwise use the ':<text>:' form
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% Page & text layout
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\makeatother

% Headers & footers
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% Indices & bibliography
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\usepackage[titles]{tocloft}
\setcounter{tocdepth}{3}
\setcounter{secnumdepth}{5}
\makeindex

\usepackage{newunicodechar}
  \newunicodechar{⁻}{${}^{-}$}% Superscript minus
  \newunicodechar{²}{${}^{2}$}% Superscript two
  \newunicodechar{³}{${}^{3}$}% Superscript three

% Hyperlinks (required, but should be loaded last)
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  \usepackage[pdftex,pagebackref=true]{hyperref}
\else
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\fi

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}

% Custom commands
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\usepackage{caption}
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\usepackage{etoc}
\etocsettocstyle{\doxytocparskip}{\doxynormalparskip}
\renewcommand{\numberline}[1]{#1~}
%===== C O N T E N T S =====

\begin{document}

% Titlepage & ToC
\hypersetup{pageanchor=false,
             bookmarksnumbered=true,
             pdfencoding=unicode
            }
\pagenumbering{alph}
\begin{titlepage}
\vspace*{7cm}
\begin{center}%
{\Large Fx\+Engine \\[1ex]\large 0.\+0.\+1 }\\
\vspace*{1cm}
{\large Generated by Doxygen 1.8.15}\\
\end{center}
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\clearemptydoublepage
\pagenumbering{roman}
\tableofcontents
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\pagenumbering{arabic}
\hypersetup{pageanchor=true}

%--- Begin generated contents ---
\chapter{Data Structure Index}
\input{annotated}
\chapter{File Index}
\input{files}
\chapter{Data Structure Documentation}
\input{structbitmap__rich}
\input{struct_f_e__floating__position}
\input{struct_f_e__integer__point}
\input{struct_f_e__integer__position}
\chapter{File Documentation}
\input{keyboard_8h}
\input{bitmap_8h}
\input{parameters_8h}
\input{translate_8h}
\input{zbuffer_8h}
%--- End generated contents ---

% Index
\backmatter
\newpage
\phantomsection
\clearemptydoublepage
\addcontentsline{toc}{chapter}{\indexname}
\printindex

\end{document}