Spiegel

n = 1.33 (slider from 1 to 3, step 1.0E-4)
B = Point(xAxis)
C = Intersect(xAxis, yAxis)
b = Segment(C, B)
H = Point(b)
A = Point(yAxis)
D: (x(B), y(A))
c = Segment(B, D)
a = Segment(A, C)
E = Point(a)
d = Line(E, b)
F = Intersect(d, c)
e = Segment(E, F)
I = Point(e)
g = OrthogonalLine(I, b)
G = Point(a)
f = Segment(G, H)
J = (-4.879594461462318, 17.953085920070105)
h = Ray(I, J)
α = Angle(g, h)
β: asin(sin(α) / n)
g' = Rotate(g, β, I)
L = Intersect(g', f)
j = OrthogonalLine(L, f)
M = Point(j)
k = Segment(M, L)
g'' = Mirror(g', k)
P = Intersect(g'', e)
m = Segment(L, P)
p = OrthogonalLine(P, xAxis)
Q = Point(p)
a_1 = Segment(P, Q)
K = Point(p)
r = Segment(K, Q)
β_1: 180 * asin(sin(α) / n) / π
i = Segment(I, L)
N = Point(g)
O = Point(g)
l = Segment(N, O)
γ = Angle(l, i)
q = Segment(K, P)
ε = Angle(M, L, I)
Vieleck1, e_1, c_1, b_1, f_1 = Polygon(E, C, B, F)
S = Point(f)
T = Point(f)
U = (5.672774698846831, -2.7236323709827146)
t = Segment(T, U)
δ = Angle(L, P, Q)
s = Segment(K, P)
α2: asin(n * sin(δ))
K' = Rotate(K, -α2, P)
d_1 = Ray(P, K')
ζ = Angle(K', P, K)