croix.tex

\documentclass{article}
\usepackage{pst-solides3d}
\begin{document}
\pagestyle{empty}
 
\begin{pspicture}(-1.5,-4)(4,6)
\psset{lightsrc=50 -50 50,viewpoint=100 -30 40,Decran=100}
\psset{solidmemory}
\psSolid[object=plantype,
   definition=equation,
   args={[0 0 1 0] 90},
   base=-6 6 -7 6,
   ngrid=9 13,
   name=monplan]
\defFunction[algebraic]{C1}(t)
    {2*cos(t)}
    {-6}
    {2*sin(t)}
\defFunction[algebraic]{C2}(t)
    {-6}
    {2*cos(t)}
    {2*sin(t)}
\psSolid[object=cylindre,
   range=0 6.28,
   h=12,
   function=C1,
   axe=0 1 0,
   incolor=green!50,
   fillcolor=yellow!50,
   ngrid=9 18,
% séparation du cylindre 1
   plansepare=monplan,
   name=cylindre1,
   action=none
]
\psSolid[object=cylindre,
   range=6.28 0,
   h=12,
   function=C2,
   axe=1 0 0,
   incolor=green!50,
   fillcolor=yellow!50,
% séparation du cylindre 2
   plansepare=monplan,
   ngrid=9 18,
   name=cylindre2,
   action=none
]
% on fusionne et dessine les parties inférieures
\psSolid[object=fusion,
   base=cylindre11 cylindre21
]
% on trace le plan défini au départ
\psSolid[object=plan,
   definition=plantype,
   args=monplan
]
% on fusionne et dessine les parties supérieures
\psSolid[object=fusion,
   base=cylindre10 cylindre20
]
\psProjection[object=texte,
   plan=monplan,
   linecolor=red,
   text=PST-solides3d,
   fontsize=20,
   pos=cc
   ](0,-6.5,0)
\composeSolid
\end{pspicture}
 
\end{document}