%% Auteur : Manuel Luque
%%
\newcommand\SectionCoupe{
0 0
1.5 0
1.5 0.2
1.5 0.2
   -90 -10 -180{
      /Angle exch def
      0.3 Angle cos mul 0.5 add % y=0.3cos(A) + 0.5
      0.3 Angle sin mul 0.5 add % z=0.3sin(A) + 0.5
   } for
0.2 3.1
-85 10 0{
      /Angle exch def
      2 Angle cos mul % y=2cos(A) + 0.5
      2 Angle sin mul 5 add % z=2sin(A) + 5
   } for
2 5
0 -10 -90{
      /Angle exch def
      1.9 Angle cos mul % y=2cos(A) + 0.5
      1.9 Angle sin mul 5 add % z=2sin(A) + 5
   } for
   }
\begin{pspicture}(-4,-3)(4,6)
\psframe(-4,-3)(4,6)
\psset[pst-solides3d]{SphericalCoor,viewpoint=70 40 30,Decran=50,lightsrc=50 40 35}
\psSolid[object=grille,base=-4 4 -4 4,fillcolor=green!30]%
\psSolid[object=anneau,section=\SectionCoupe,fillcolor=cyan!30,linecolor=blue]%
\axesIIID(1.5,1.5,4)(4,4,7)
\end{pspicture}