mathdimen.sty

\ProvidesPackage{mathdimen}[2012/03/01 v0.1]

\RequirePackage{newfile,etoolbox}

%variable definitions
\@ifpackageloaded{tex4ht}{}{
\newoutputstream{mathdim}
\openoutputfile{\jobname.mtd}{mathdim}
}
\newcount\dmath@count
\newbox\MathBox


\newcommand\save@math@dimens{%
\addtostream{mathdim}{\noexpand\mathdim{\the\dmath@count}{\the\wd\MathBox}{\the\ht\MathBox}{\the\dp\MathBox}}
}

\newcommand\step@math@count{\global\advance\dmath@count by1\relax}
% Display math definitions
\newcommand\Start@math@box{%
\setlength{\abovedisplayskip}{0pt}
\setlength{\belowdisplayskip}{0pt}
\setbox\MathBox=\vbox\bgroup
}
\newcommand\End@math@box{%
\egroup\copy\MathBox%
\setbox\MathBox=\vbox{\unvbox\MathBox\unskip\unpenalty\unkern}%
\step@math@count
%\advance\dmath@count by1\relax%
%Výška: \the\ht\MathBox, šířka \the\wd\MathBox
%\addtostream{mathdim}{\noexpand\mathdim{\the\dmath@count}{\the\wd\MathBox}{\the\ht\MathBox}{\the\dp\MathBox}}
\save@math@dimens
}

%We must redefine the math commands
\let\oldbdisplay\[
\let\oldedisplay\]
\let\oldbmath\(
\let\oldemath\)


\renewcommand\[{%\]
\Start@math@box\oldbdisplay
}

\renewcommand\]{%
\oldedisplay\End@math@box
} 
\renewcommand\({%%%    \) end brackets because of broken syntax highlighting in gedit
\setbox\MathBox=\hbox\bgroup\oldbmath
}

\renewcommand\){%
\oldemath\egroup%
\step@math@count
\save@math@dimens
}
\BeforeBeginEnvironment{equation}{\Start@math@box}
\AfterEndEnvironment{equation}{\End@math@box}