%% 
%%  Ein Beispiel der DANTE-Edition
%%  
%%  7. Auflage
%% 
%%  Beispiel 15-02-1 auf Seite 254.
%% 
%%  Copyright (C) 2016 Herbert Voss
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{193.16928pt}
\setlength\parindent{0pt}
\usepackage{pst-node}
\def\Square{\rule{1cm}{1cm}}
\def\BildI{%
\begin{pspicture}[showgrid](5,1)
\Rnode{A}{\Square}\hspace{3cm}\Rnode{B}{\Square}
\ncline[linecolor=red,style=line]{A}{B}
\end{pspicture}}
\def\BildII{%
\begin{pspicture}[showgrid](5,4)
\rput[lb](0,0){\Rnode{A}{\Square}\hspace{3cm}%
    \Rnode[vref=3cm]{B}{\Square}}
\psframe*[linecolor=black!20](4,3)(5,4)
\pcline[linecolor=red,linestyle=dotted,linewidth=2pt](A)(B)
\ncline[linecolor=red,style=line]{A}{B}
\pnode(4,0.7ex){C}
\ncline[linecolor=blue,style=line]{A}{C}
\pcline{->}(4.5,0.5)(4.5,3.5)\uput[0](3.5,2){vref}
\end{pspicture}}
\newpsstyle{line}{linewidth=2pt,arrowscale=2,arrows=->}
%StartShownPreambleCommands
\usepackage{pst-node}
%StopShownPreambleCommands
\begin{document}
\psscalebox{0.8}{\BildI}\\[12pt]
\psscalebox{0.8}{\BildII}\\[12pt]
\psscalebox{0.8}{%
 \begin{pspicture}[showgrid](7,4)%
  \rput[lb](0,0){\Rnode{A}{\Square}%
   \hspace{3cm}%
   \Rnode[href=4,vref=3cm]{B}{\Square}}
  \psframe*[linecolor=black!20](4,3)(5,4)
  \psframe*[linecolor=black!20](6,3)(7,4)
  \psline[arrows=->](4.5,3.5)(6.5,3.5)
  \uput[-90](5.5,3.5){href}
  \pcline[linecolor=red,linestyle=dotted,
    linewidth=2pt](A)(B)
  \ncline[linecolor=red,style=line]{A}{B}
  \pnode(4,0.7ex){C}
  \pcline{->}(4.5,0.5)(4.5,3.5)
  \uput[0](3.5,2){vref}
  \pcline[linecolor=white](3.5,0.5)(3.5,1)
  \ncline[linecolor=blue,style=line]{A}{C}
\end{pspicture}}
\end{document}
