d = 6.5 (slider from 1 to 6.5, step 0.5)
α = 0 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
M: (d * α / 2, d / 2)
D: (x(M) + d / 2 * cos(-α), y(M) + d / 2 * sin(-α))
c = Circle(M, D)
a = Line(D, M)
b = OrthogonalLine(M, a)
A, B = Intersect(c, a)
C, E = Intersect(c, b)
e = Segment(B, D)
f = Segment(C, E)
g = AngularBisector(B, M, E)
h = AngularBisector(C, M, B)
F, G = Intersect(c, h)
H, I = Intersect(c, g)
i = Segment(I, H)
j = Segment(G, F)
J, K = Intersect(c, xAxis)
k = CircleArc(M, E, K)
p = CircleArc(M, K, E)
L = Intersect(xAxis, yAxis)
N = (0, 0)
l = Segment(N, K)
O: ((-d) / 2, 0)
m = OrthogonalLine(O, xAxis)
P, Q = Intersect(c, m)
q = Circle(M, Q)
R: (π * d + d / 2, 0)
n = OrthogonalLine(R, xAxis)
S, T = Intersect(c, n)
r = Circle(M, T)