A = Point(xAxis)
B = Point(yAxis)
C = Point(xAxis)
D = Point(yAxis)
u = Vector(A, C)
v = Vector(B, D)
f = Ray(A, u)
g = Ray(B, v)
F_1 = Point(f)
Objektiv = Point(g)
O = Intersect(xAxis, yAxis)
w = Vector(O, Objektiv)
a: (-w)
o = Line(O, u)