\relax

\documentclass{article}
\usepackage{fontdoc}

\begin{document}

\title{\texttt{glyphbox.mtx}: showing metric boxes of glyphs}
\author{Lars Hellstr\"om}
\date{July 2003}
\maketitle

\begin{abstract}
  This file redefines the \verb|\setscaledrawglyph| command to make a 
  thin ($5$ AFM units) frame lining the inside of the metric box of 
  the glyph. This is can be useful when debugging commands for 
  building glyphs, as it gives graphic account of the glyph metrics. 
  Use \verb|\oncommand\setscaledrawglyph| or the \texttt{glyphon.mtx} 
  file to restore the normal command definition.
\end{abstract}


\begin{verbatim}

\metrics

\needsfontinstversion{1.914}


\offcommand\setscaledrawglyph

\resetcommand\setscaledrawglyph#1#2#3#4#5#6#7#8#9{%
   \csname saved-\string\setscaledrawglyph\endcsname
      {#1/raw}{#2}{#3}{#4}{#5}{#6}{#7}{#8}{#9}%
   \setglyph{#1}%
      \push
         \moveup{\neg{#8}}%
         \glyphrule{5}{\add{#7}{#8}}%
         \push
            \ifnumber{#9}{>}{0}\then
               \moveup{\add{#7}{#8}}%
               \glyphrule{\add{\sub{#6}{5}}{#9}}{5}%
            \else
               \moveup{\add{#7}{#8}}%
               \glyphrule{\sub{#6}{10}}{5}%
            \fi
         \pop
         \glyphrule{\sub{#6}{10}}{5}%
         \glyphrule{5}{\add{#7}{#8}}%
      \pop
      \glyph{#1/raw}{1000}%
   \endsetglyph
}


\endmetrics


\end{verbatim}


\end{document}