%% d'apres les donnees de %% http://www.mathcurve.com/courbes3d/solenoidtoric/solenoidtoric.shtml -3 3 setxrange -3 3 setyrange 50 setxunit 0.01 0 50 SetCamPos 0 0 0 SetCamView /ScreenDist .05 def -10 10 setxrange3d -3 3 setyrange3d 2 setlinejoin /m 12 def %% ex R /r 8 def /n 3 1 div def /g { 3 dict begin settvar #rpn# (m+r*Cos(n*t))*Cos(t) #rpn# (m+r*Cos(n*t))*Sin(t) #rpn# r*Sin(n*t) end } def /g' { 3 dict begin settvar #rpn# -n*r*Sin(n*t)*Cos(t) - (m+r*Cos(n*t))*Sin(t) #rpn# -n*r*Sin(n*t)*Sin(t) + (m+r*Cos(n*t))*Cos(t) #rpn# n*r*Cos(n*t) end } def /g'' { 3 dict begin settvar #rpn# -n^2*r*Cos(n*t)*Cos(t) +n*r*Sin(n*t)*Sin(t) + n*r*Sin(n*t)*Sin(t) - (m+r*Cos(n*t))*Cos(t) #rpn# -n^2*r*Cos(n*t)*Sin(t) -n*r*Sin(n*t)*Cos(t) - (n*r*Sin(n*t))*Cos(t) - (m+r*Cos(n*t))*Sin(t) #rpn# -n^2*r*Sin(n*t) end } def %rouge %0 pi 4 mul {g} CourbeR3 % stop .1 setlinewidth %/aretescachees false def GetCamPos setlightsrc %solidgridOff 0 4 pi mul (g) 1 [200 8] newtube dupsolid dupsolid dupsolid dup [.5 .6] solidputhuecolors /A exch def dup [0 .1] solidputhuecolors {0 0 90 rotateOpoint3d} solidtransform /B exch def dup [.2 .3] solidputhuecolors {0 0 180 rotateOpoint3d} solidtransform /C exch def dup [.8 .9] solidputhuecolors {0 0 -90 rotateOpoint3d} solidtransform /D exch def A B C D solidfuz solidfuz solidfuz drawsolid**