anim.tex

\documentclass{article}
\usepackage[dvipsnames,svgnames]{pstricks}
\usepackage{pst-solides3d,pstricks-add}
\pagestyle{empty}
 
\begin{document}
 
\psset{unit=0.75}
 
\multido{\r=70+-1}{55}{
\begin{pspicture}(-6,-3)(6,8)
\psset{%
    lightsrc=\r\space 20 \r\space,
    viewpoint= 30 50 \r\space,
    Decran=70
    }
\pstVerb{%
    /ry 50 sin neg def
    /rz 50 neg def
    }
\psSolid[%
    object=grille,
    base=-6 6 0 6,
    RotX=-30,
    fillcolor=lightgray,
    linecolor=black,
    linewidth=0.01
    ]
\psSolid[%
    object=grille,
    base=-6 6 -6 6,
    fillcolor=lightgray,
    linecolor=black,
    linewidth=0.01
    ]
\psSolid[%
    object=grille,
    base=-6 6 -6 0,
    RotX=-50,
    fillcolor=lightgray,
    linecolor=black,
    linewidth=0.01
    ]
\axesIIID(0,0,0)(7,7,7)
\deffunction[algebraic]{fonction}(x){x}{}{-x^2+4}
\psProjette[%
   object=courbeR2,
   range=-2 2,
   linewidth=.1,
   linecolor=blue,
   normale=0 ry rz,
   function=fonction](0,0,0)
\psProjette[%
   object=courbeR2,
   range=-2 2,
   normale=0 -1 0,
   linewidth=.1,
   linecolor=green,
   function=fonction](0,0,0)
\end{pspicture}
\newpage
}
 
\end{document}