
% debugging stuff
\def\vruler#1{{%
        \def\wid{\dimen0}%
        \def\inc{\dimen1}%
        \wid=#1pt
        \inc=\wid
        \divide\inc by #1
        \divide\wid by 2
        \here=-\wid
        \loop\ifdim\here<\wid\advance\here by\inc
                \hbox to0pt{\vbox to0pt{\vss\hrule width2pt height 0.05pt\kern\here}\hss}%
        \repeat%
}}
\def\hruler#1#2{\hbox{%
        \def\wid{\dimen0}%
        \def\here{\dimen3}%
        \wid=#1pt
        \divide\wid by 2
        \here=-\wid
        \loop\ifdim\here<\wid\advance\here by #2
                \hbox to0pt{\kern\here\vrule width0.05pt height 1pt depth 1pt\hss}%
        \repeat%
}}


