How do I make the list of figures use an automatically shortened version of the caption?

Question

Many of my captions are quite long and appear as 5 or more lines in the list of figures. To save me the effort of using the optional argument in the caption are there any packages that can produce the list of figures with just the first line and some sort of symbol to indicate that that is not the full caption?

Answer 1

An alternative implementation, shortening the caption in the lof while typesetting it...

\documentclass{article}
\showboxdepth1
\showboxbreadth100
\makeatletter
\long\def\l@figure#1#2{%
\setbox0\vbox{%
\def\lpx{\interlinepenalty-\@M}%
\advance\hsize -1em
\@dottedtocline{1}{1.5em}{2.3em}{\aftergroup\lpx#1bbbb}{#2}}%
\ifdim\ht0>\baselineskip
\begingroup
\vbadness\maxdimen
\setbox2=\vsplit0to \baselineskip
\setbox4\vbox{%
\unvbox2
\global\setbox1\lastbox}%
\endgroup
\noindent\hbox to \linewidth{\unhbox1\unskip!!%
\dotfill\hb@xt@\@pnumwidth{\hfil\normalfont \normalcolor #2}%
%\kern\@tocrmarg
}%
\else
\@dottedtocline{1}{1.5em}{2.3em}{#1}{#2}%
\fi
}
\begin{document}

\listoffigures

\begin{figure}[!b]
\caption{One one one a  longish caption.}
\end{figure}



\begin{figure}[!b]
\caption{A short caption.}
\end{figure}


\begin{figure}[!b]
\caption{This one is a very  very  very  very  very  very  very 
 very  very  very  very  very long caption.}
\end{figure}


\def\z{even longer than before }
\begin{figure}[!b]
\caption{Hmmm \z\z\z. Very long caption. More \z\z\z.}
\end{figure}

\end{document}

Answer 2

You can try and truncate the caption argument, but be warned that typographically this will look very poor.

You will need to add two packages, one is the caption package and the other the truncate package. we define a new command \Caption to be used as:

\Caption[optional width spec.]{caption text ..............}

Variations are also possible and I leave that for you to experiment with.

\documentclass{article}
\usepackage{truncate}
\usepackage{caption}
\begin{document}
\listoffigures
\DeclareRobustCommand\Caption[2][130pt]{\captionof{figure}{\truncate{#1}{#2}}}
\begin{figure}
\Caption{This is my famous half a kilometer long caption that has been truncated}
\end{figure}
\begin{figure}
\Caption{This is my famous half a kilometer long caption that has not been truncated}
\end{figure}
\end{document}

You can disable the effects later by redeclaring the \Caption command as follows:

 \DeclareRobustCommand{\Caption}[2][]{\captionof{figure}{#2}}

I can think of many other ways to provide the input and this will ultimately depend, if one needs to leave the shortened version permanently or not.