a = 3; b = 6; c = Sqrt[b^2 - a^2]; fx[s_, t_] := (a*Cos[t] + b)Cos[s]; fy[s_, t_] := (a*Cos[t] + b)Sin[s]; fz[s_, t_] := a Sin[t]; fxx[s_, t_] := (c*fx[s, t] + a*fz[s, t])/b; fyy[s_, t_] := fy[s, t]; fzz[s_, t_] := (-a*fx[s, t] + c*fz[s, t])/b; Do[ ParametricPlot3D[{fxx[s, t], fyy[s, t], fzz[s, t]}, {t, 0, 2Pi},{s, -Pi, Pi }, PlotRange -> {{-(a + b + 1), a + b + 1}, {-(a + b + 1), a + b + 1}, {-(a + b + 1) + i, i}}, Axes -> False, PlotPoints -> {51, 71}, ViewPoint -> {0.934, -1.725, 2.757}, DisplayFunction -> $DisplayFunction], {i, b, -b, -1}] |