animT(x) = cos(π / 2 - (π / 2 * x))^(4)
t1 = 1 (slider from 0 to 1, step 0.01)
B: (1, 0)
C = PointIn(y > 0)
A: (0, 0)
c = Circle(C, A)
h = Segment(A, B)
i = Line(C, h)
D = Intersect(c, i, 1)
e = CircleArc(C, D, A)
d = Circle(C, B)
E = Intersect(d, i, 2)
F = Point(e, 1 - animT(t1))
k = CircleArc(C, B, E)
G = Point(k, animT(t1))
j = Segment(F, C)
l = Segment(C, G)
t2, b, a, c_1 = Polygon(A, C, B)
H: (x(C), y(C))
u = Vector(F, C)
v = Vector(C, G)
w = Vector(A, B)
draggingC = false
fadeTimer = 1 (slider from 0 to 1, step 0.01)