%% 
%%  A DANTE-Edition example
%% 
%%  Example 29-02-7 on page 567.
%% 
%%  Copyright (C) 2011 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[]{article}
\pagestyle{empty}
\setlength\textwidth{153.70511pt}
\setlength\parindent{0pt}

\usepackage{pst-eucl}

\begin{document}
\begin{pspicture}(-1.5,-1.5)(1.5,1.5)
  \pstGeonode(1,1){A}(-1,-1){B}(-1,1){C}(1,-1){D}
  \pstLineAB{C}{D}
  \psset{linecolor=blue,linewidth=2pt}
  \pstLineAB[nodesep=-0.6,linecolor=lightgray]{A}{B}
  \pstLineAB{A}{B}% overwrite line
\end{pspicture}
\end{document}