Footnote indentation 1.25cm of multiple lines footnotes

Question

I am trying to indent multiline footnotes 1.25cm after and including the second line.

This is the code fragment that my template uses to set-up footnotes, which needs to be adapted:

\AtBeginDocument{% 
\renewcommand\@makefntext[1]{%
\parindent 12\p@ 
\noindent 
\mbox{\@makefnmark} #1}}

I found a general answer to a similar question by @egreg, as follows:

\makeatletter
\renewcommand\@makefntext[1]{\leftskip=2em\hskip-2em\@makefnmark#1}
\makeatother

However, while I can include this answer to my code fragment so that there is some indent, I can't get it to do what I want it to, i.e. indent 2.5 cm. Also, I am not entirely sure whether my code modification is right, since my try at merging the two code fragments was more or less a guesstimation.

How do I modify my (the first) code fragment to keep the settings in principle, but add an indentation from the second line of 1.25cm using the method as described?

Answer 1

Are you looking for something like this?

\documentclass{article}

\usepackage{lipsum}

\makeatletter
\renewcommand\@makefntext[1]{%
  \@setpar{%
    \@@par \@tempdima=\hsize
    \advance\@tempdima by -1.25cm\relax
    \parshape \@ne 1.25cm \@tempdima
  }%
  \par \parindent=\z@ \noindent
  \hb@xt@ \z@{\hss \hb@xt@ 1.25cm{\@thefnmark.\hss}}%
  #1%
}
\makeatother

\begin{document}
\vspace*{\fill}Text\footnote{\lipsum[1]}
\end{document}

Answer 2

Since you're only mentioning multi-lined footnotes (and not multi-paragraph footnotes), the following provides what you're after:

\documentclass{article}

\usepackage[paperheight=20\baselineskip]{geometry}% Just for this example
\usepackage{lipsum}

\makeatletter
\renewcommand\@makefntext[1]{%
  \parshape \@ne 1.25cm \dimexpr\hsize-1.25cm\relax% Set up the generic paragraph shape:
                                                   %   Indentation of first (and following) lines are 1.25cm
                                                   %   Width are \hsize-1.25cm (to fit horizontally)
  \noindent % Start paragraph
  \hspace*{-1.25cm}% Jump back (horizontally) the width of the indentation
  \makebox[12\p@][l]{\@makefnmark}% Set a box of width 12\p@ that is [l]eft aligned and insert the footnote mark
  #1}% Set the rest of the footnote as a paragraph
\makeatother

\begin{document}
Text\footnote{\lipsum[1]}. More text\footnote{\lipsum[2]}.
\end{document}

Comments in the code explain the components of the \@makefntext construction.