%% 
%%  A DANTE-Edition example
%% 
%%  Example 07-01-24 on page 88.
%% 
%%  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{177.70511pt}
\setlength\parindent{0pt}

\usepackage{pstricks}
\psset{unit=0.75}

\begin{document}
\begin{pspicture}[linewidth=1cm](4,4)
  \psline[linecolor=red](0,0)(4,4)
  \pscircle*[opacity=0.5](2,2){2}
  \psline[linecolor=blue,
    strokeopacity=0.6](0,4)(4,0)
\end{pspicture}
\end{document}