basically when you go to the left edge it brodcasts to the map to move right, and if you are at Green the it moves to the right blue does too and takes it's place there I came up with this myself but I would be very surprised if no one has already done it before.
if you want to use this and not let the player go out of bounds you just add the coordinates to the list in the backdrop like to coordinates of blue is 5190 because its x=519 and y=0