X' = -X   [ O=med(X,X')=(X+X')/2 ]
P = exp(i·t)
M = med(U,P) = (U+P)/2
B = med(O,U,M) = (O+U+M)/3
C = simmetrico(M,B)   [ B=med(M,C)=(M+C)/2 ]

t = 3.14 (slider from 0 to 3.141592653589793, step 0.002)
O = (0, 0)
U = (1, 0)
U': -U
P: exp(ί * t)
a = Segment(U, P)
M = Midpoint(U, P)
U'_1 = Mirror(U, O)
U'' = Mirror(U', O)
P' = Mirror(P, O)
M' = Mirror(M, O)
U'_2 = Mirror(U, O)
P'_1 = Mirror(P, O)
a' = Segment(U'_2, P'_1)
B: (O + U + M) / 3
C = Mirror(M, B)
B' = Mirror(B, O)
C' = Mirror(C, O)
b = Segment(B, C)
d = Segment(U, M)
e = Segment(M, P)
f = Segment(C', B')
g = Segment(U', M')
h = Segment(M', P')