% Copyright 2026 Adi Edelhaus
%
% terminaltrees is licensed under the LaTeX Project Public
% License, version 1.3c or any later version.
%
% Maintenance status: maintained
% Current maintainer: Adi Edelhaus
% Issue reports: https://github.com/edel67/terminaltrees/issues
%
% The files comprising this work are listed in manifest.txt.
% See LICENSE for the full license terms.

\documentclass{article}
\usepackage[paperwidth=220mm,paperheight=140mm,textwidth=150mm,
  top=15mm,bottom=15mm]{geometry}
\usepackage{terminaltrees}
\input{terminaltrees-tests/trace.tex}
\pagestyle{empty}
\setlength{\parindent}{0pt}
\AddToHook{shipout/background}{%
  \typeout{PAGE AREA: \the\pdfpagewidth;
    \the\dimexpr1in+\hoffset+\oddsidemargin\relax;\the\textwidth}%
  \begin{tikzpicture}[remember picture,overlay]
    \draw[gray!50] (current page.north west)
      ++({1in+\hoffset+\oddsidemargin},
         {-1in-\voffset-\topmargin-\headheight-\headsep})
      rectangle ++(\textwidth,-\textheight);
  \end{tikzpicture}}

% A deliberate minimum pitch makes this tree wider than the smaller text area.
% All pages use the same tree and starting typography.
\newcommand{\Example}[1]{%
  #1{leaf pitch=16mm,
    [ROOT [PAIR [alpha] [beta]] [PAIR [gamma] [delta]]
      [PAIR [epsilon] [zeta]] [PAIR [eta] [theta]]]}}
\newsavebox{\unfittedtree}
\newcommand{\Unfitted}[1]{%
  \sbox{\unfittedtree}{\begin{forest}terminal tree, #1\end{forest}}%
  \typeout{UNFITTED WIDTH: \the\wd\unfittedtree}%
  \typeout{UNFITTED AVAILABLE: \the\linewidth}%
  \makebox[\linewidth][c]{\usebox{\unfittedtree}}\par}
\newcommand{\Fitted}[1]{%
  \begin{fittedterminaltree}#1\end{fittedterminaltree}}

\begin{document}
\vspace*{1em}
{\Large\sffamily\bfseries Unfitted on larger paper}\par\medskip
\texttt{forest} with \texttt{terminal tree}\par\medskip
Keep 10pt labels by choosing paper large enough for the unscaled tree.
\par\bigskip
\Example{\Unfitted}
\vfill
Frame: text area (150mm wide). Paper: 220 by 140mm. Side margins: 35mm.
You set the paper size in LaTeX. Neither environment changes it.
\par\vspace*{1em}
\clearpage
\setlength{\paperwidth}{170mm}
\pdfpagewidth=\paperwidth
\newgeometry{left=35mm,textwidth=100mm,top=15mm,bottom=15mm}
\vspace*{1em}
{\Large\sffamily\bfseries Fitted on smaller paper}\par\medskip
\texttt{fittedterminaltree}\par\medskip
The tree shrinks uniformly to fit the text width. The page margins do not change.
\par\bigskip
\Example{\Fitted}
\vfill
Frame: text area (100mm wide). Paper: 170 by 140mm. Side margins: 35mm.
Labels and branches scale together without dropping below the minimum label size.
\par\vspace*{1em}
\newpage
\vspace*{1em}
{\Large\sffamily\bfseries When the page is too small}\par\medskip
\texttt{forest} with \texttt{terminal tree}\par\medskip
The same unscaled tree on the smaller paper extends into the margins.
\par\bigskip
\Example{\Unfitted}
\vfill
This is a deliberately unsuitable page size, not a different tree layout.
Choose larger paper or use fitting.
\par\vspace*{1em}
\end{document}

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