% \iffalse meta-comment
%
% arcs.dtx
% Copyright 2004 Gianfranco Boggio-Togna
% 
% This program may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version~1.2
% of this license or (at your option) any later version.
% The latest version of this license is in
% http://www.latex-project.org/lppl.txt
% and version 1.2 or later is part of all distributions of LaTeX  
% version 1999/12/01 or later.
%
% This program consists of the files arcs.dtx and arcs.ins
%
%<*driver>
\documentclass[11pt]{ltxdoc}
\setlength{\parindent}{0pt}
\setlength{\parskip}{1ex}
\MakeShortVerb{|}
% To get the documented source of the package, comment out
% the next line and uncomment the following one.
\OnlyDescription
%\AlsoImplementation
\begin{document}
  \DocInput{arcs.dtx}
\end{document}
%</driver>
%
% \fi
%
% \CheckSum{188}
% \makeatletter
% \let\ps@titlepage=\ps@empty
% \makeatother
%
% \title{{\LARGE\tt arcs.sty}\\
%         Placing an arc over (under) some text\\
%         {\small Version 1\ \ (2004/05/09)}\\\ \\}
% \author{Gianfranco Boggio\,--Togna\\
%         \textsl{gbt\kern .08em @\kern .1em acm.org}}
% \date{}
% \maketitle
% \vspace{6ex}
% The package provides two commands for placing an arc over or under 
% a short (up to three letters) piece of text.  The commands generate an
% |\hbox| and can be used in math formulas
% (see \textit{The \TeX{}book}, p.\,151).
%
% |\overarc| puts an arc above the text given as argument.\\
% |\underarc|  puts the arc below the text.
%
% The size of the arc is chosen so that it embraces all the text. In
% some cases, you may wish to use a smaller or larger size. An
% optional argument can specify a factor which 
% is multiplied by the width of the text: the size of the symbol is then
% chosen as if the text had that width. Keep in mind, however, that only
% a limited range of sizes is available in the Computer Modern fonts.
% \vfill
% {\footnotesize
% \noindent \copyright\ Copyright 2004 Gianfranco Boggio\,--Togna.\par
% This program may be distributed and/or modified under the
% conditions of the \LaTeX{} Project Public License, either version~1.2
% of this license or (at your option) any later version. 
% The latest version of this license is in  
% \texttt{http://www.latex-project.org/lppl.txt} 
% and version 1.2 or later is part of all distributions of \LaTeX{} 
% version 1999/12/01 or later.\par
% This program consists of the files \texttt{arcs.dtx} and 
% \texttt{arcs.ins}
% }
% \newpage
% \StopEventually{}
% \section*{The code}
%    \begin{macrocode}
\NeedsTeXFormat {LaTeX2e}[2003/12/01]
\ProvidesPackage {arcs}[2004/05/09]
\RequirePackage {relsize}
\newcommand{\overarc}[2][1]{\over@under@arc{#1}{#2}\z@}
\newcommand{\underarc}[2][1]{\over@under@arc{#1}{#2}\@ne}
\newcommand{\over@under@arc}[3]{%
  \leavevmode
  \hbox {%
    \setbox\z@ = \hbox {#2}%
    \ifdim \ht\z@ = \z@ %      arc over/under space
      \ifdim \dp\z@ = \z@ 
        \ht\z@ = 1ex\relax
      \fi
    \fi
    \dimen@ = #1\wd\z@ 
    \begingroup
    \let \rs@size@warning = \@gobbletwo
    \relsize{-10}%
    \wd\@ne = \z@
    \@whiledim \wd\@ne < .95\dimen@ \do {%
      \ifx \@currsize \Huge
        \dimen@ = \z@
      \else
        $%
        \skip@ = \f@baselineskip
        \fontencoding{OML}\fontfamily{cmm}\fontseries{m}%
        \fontshape{it}\fontsize{\ssf@size}{\skip@}\selectfont
        \global \setbox\@ne = \hbox {%
           \hss\symbol{"5\ifnum #3=\z@ F\else E\fi}\hss}%
        \ifdim \wd\@ne < \dimen@ 
          \fontsize{\sf@size}{\skip@}\selectfont
          \global \setbox\@ne = \hbox {%
             \hss\symbol{"5\ifnum #3=\z@ F\else E\fi}\hss}%
          \ifdim \wd\@ne < \dimen@ 
            \fontsize{\tf@size}{\skip@}\selectfont
            \global \setbox\@ne = \hbox {%
              \hss\symbol{"5\ifnum #3=\z@ F\else E\fi}\hss}%
          \fi
        \fi
        $%
      \fi
      \ifdim \wd\@ne < \dimen@ 
        \relsize{+1}%
      \fi
      \global \dimen@i = \fontdimen5\the\font
    }%
    \endgroup
    \ifnum #3 = \z@
      \dimen@ii = 1.067\ht\z@ 
      \global \divide \dimen@i by \tw@
      \global \advance \dimen@i by -\ht\@ne
      \advance \dimen@ii by .6\dimen@i
    \else
      \dimen@ii = -1.05\ht\@ne
      \advance \dimen@ii by -.75pt
      \ifdim \dp\z@ > \z@ 
        \advance \dimen@ii by -\dp\z@ 
      \fi
    \fi
    \copy\z@ 
    \dimen@ = \wd\z@ 
    \advance \dimen@ by \wd\@ne 
    \kern -.5\dimen@ 
    \raisebox {\dimen@ii}[\z@][\z@]{\copy\@ne}%
    \dimen@ = \wd\z@ 
    \advance \dimen@ by -\wd\@ne 
    \dimen@ = .5\dimen@ 
    \kern \dimen@
  }%
}
%    \end{macrocode}
%% \Finale
\endinput
