%%
%%  A DANTE-Edition example
%%
%%  Example 07-01-20 on page 87.
%%
%%  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{pstricks}
\psset{unit=0.75}

\begin{document}
\begin{pspicture}[linewidth=1cm](4,4)
 \psline[linecolor=red](0,0)(4,4)
 \psline[linecolor=blue,strokeopacity=0.5](0,4)(4,0)
 \psline[linecolor=green,
   strokeopacity=0.5](0,3.5)(4,3.5)
 \psline[linecolor=yellow,
   strokeopacity=0.5](0,0.5)(4,0.5)
\end{pspicture}
\end{document}