\documentclass{article} \usepackage{pst-solides3d} % Jean-Paul Vignault % Manuel Luque \pagestyle{empty} \begin{document} \psset{lightsrc=75 -63 17,SphericalCoor=true,viewpoint=100 -45 10,Decran=50,fontsize=50} \multido{\iRotZ=0+10}{36}{ \begin{center} \begin{pspicture*}(-5,-3)(5,4) \psframe(-5,-3)(5,4) \pstVerb{/iRotZ \iRotZ\space def}% \psSolid[object=grille,base=-7 7 -7 7,ngrid=1. 1.,action=draw,linecolor=red](0,0,-3.4) \defFunction[algebraic]{helix}(u,v)% {2*(0.4*cos(v)-1)*cos(u)} {2*(0.4*cos(v)-1)*sin(u)} {0.4*sin(v)+0.3*u} \codejps{ /helice -10 10 0 6.28 [60 0.4] {helix} newsurfaceparametree {0 0 iRotZ rotateOpoint3d} solidtransform {0 -4 0 translatepoint3d} solidtransform dup solidfacesreverse def /helicesym helice dupsolid exch pop {[0 1 0 0] symplan3d} solidtransform dup solidfacesreverse def /solidgrid false def solidlightOn helicesym dup [0 1 0.5 1] solidputhuecolors dup (White) inputcolors drawsolid** .5 setfillopacity [0 1 0 0] eq2plan dup [-7 7 -5 3.4] planputrange dup [14. 8.4] planputngrid newplan dup videsolid dup (0.7 0.7 1 setrgbcolor) (0.7 0.7 1 setrgbcolor) inoutputcolors drawsolid** helice dup [0 1 0.5 1] solidputhuecolors dup (White) inputcolors drawsolid** } \end{pspicture*} \end{center}\newpage} \end{document}