Quantum 2D wave packet
Ψ(r) = exp(-(r -
ro )2 + i k r) moves along the k = (ko , ko ) direction.
It is reflected by the middle horizontal line y = 0
(that is Ψ |y = 0 = 0 ).
To get this reflection we add one more (imaginary) packet
Ψ'(r) = - exp(-(r +
ro )2 + i k' r),
k' = (ko , -ko ).
We save Re(Ψ), Im(Ψ) in texture. Then "move" it and add
"imaginary" packet. |Ψ|2 is plotted.
In a similar way (by summation of translated textures)
one can get interference fringes from complicated sources. But I'm not sure
if it is very funny or useful.