Here's one where we treat the abdomen differently.
First, look at this as a 2D parametric curve:
r[t_] := E^Sin[t] - 24/10 Cos[4 t] + Sin[t/12]
x[t_] := r[t] Cos[t]
y[t_] := r[t] Sin[t]
We can locate the abdomen by carefully partitioning the roots of x[t]
.
vals = First[Cases[Plot[Evaluate[x[t, 0]], {t, 0, 20π}], Line[l_] :> l, ∞]];
xroots = t /. FindRoot[x[t], {t, ##}, WorkingPrecision -> 30] & @@@
Select[Partition[vals, 2, 1], Sign[#[[1, 2]]] != Sign[#[[2, 2]]] &][[All, All, 1]];
We now will define the abdomen through inequalities of our parameter t
.
AbdomenQ[r_] := With[{s = Chop@y[r]},
s < 0 || (s > 1 && s > Chop@y[r - 1/100])
]
abdomenextrema = Select[xroots, AbdomenQ];
abdomen = N[Or @@ (#1 <= t <= #3 & @@@
Cases[Partition[xroots, 3, 1], {_, Alternatives @@ abdomenextrema, _}])];
Now when we define our 3D parametric equation, we need to make sure our point rotates if and only if it's on a wing.
r[t_] := E^Sin[t] - 24/10 Cos[4 t] + Sin[t/12]
(x[t_, a_] := If[#, r[t] Cos[t], r[t] Cos[t] Cos[a]]) &[abdomen]
y[t_, a_] := r[t] Sin[t]
(z[t_, a_] := If[#, 0., Sign[a] Abs[r[t] Cos[t] Sin[a]]])&[abdomen]
We also keep the abdomen black and make the wings colorful.
cf = Function[{x, y, z, t},
If[#,
Black,
#2[Sqrt[x^2 + y^2]/6]
]
]&[abdomen, ColorData["FruitPunchColors"]];
And now we place this in a nicely formatted Animate
.
Animate[ParametricPlot3D[{x[t, a], y[t, a], z[t, a]}, {t, 0, 20π},
PlotRange -> 8 {{-1, 1}, {-1, 1}, {-1, 1}},
PlotPoints -> ControlActive[100, Automatic],
ColorFunction -> cf,
ColorFunctionScaling -> False,
Boxed -> False,
Axes -> False
],
{{a, 0.001}, -Pi/6, Pi/2},
AnimationDirection -> ForwardBackward,
AnimationRate -> 1
]