Would map layering be possible?

I've always wondered this. Does Rgss have enough ability to literally layer 2 maps on top of each other?

An example, in my game i want to have a 2 story building with, on the second floor, a large opening to reveal the map considered below that floor. I also want the transition to be literally instantaneous, which doesn't seem possible due to transitions and the likes and, in my opinion, would look better by hiding the top floor map anyway.

How I'd imagine it to show the bottom floor would be a lot like background images. You put in the transparent background tile that would normally give you the background image, but instead it's grab another map you'd reference (maybe in the map names?)

So would that be possible, or am I dreaming too big? :p

Can't you just put the corresponding map on the place where the whole is and use a program to make it darker and add some shadows?

Sure why not? IceDragon (?) has written map merge scripts that allows you to load tiles from different maps into another map.

Pre-load everything then.

But it may be better to write the script in a way such that the stuff you don't need to care about, aren't adding extra processing for you.

You can make the bottom floor a parallax and map on top of it.