%% 
%%  A DANTE-Edition example
%% 
%% 
%%  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{375.57637pt}
\setlength\parindent{0pt}

\usepackage{pst-solides3d}

\begin{document}
\psset{lightsrc=30 30 25,viewpoint=50 40 20 rtp2xyz,Decran=20}
\begin{pspicture}(-6,-8)(7,8)
\psSurface[ngrid=.25 .25,inouthue=1 0 0.5 1,linewidth=0.01,axesboxed,algebraic]%
    (-4,-4)(4,4){ ((y^2)-(x^2))/4 }
\end{pspicture}
\end{document}