This fun little mod was created in an attempt to see how many structures we can get floating in a floating island world. The normal behavior is that the structures spawn at the bottom of the world which looks weird. Like houses right on the void at y = 0. This mod lets you specify a y value in the config that it should try and shift all structures to. By default, this is 50.
There is also a config for making some structure pillars not go into the void and there is another config for if you want to just remove structure pieces entirely if they at at the world's bottom instead of making them float. You can blacklist structures so they do not get affected by this mod but some parts of MC's code does not let me know what structure a piece is from so this config may not stop all behaviors of this mod on a specific structure.
Currently, this mod will affect any dimension where its sealevel is set below the world's minimum y value. This does mean that this mod affects the End dimension as well...
But give this mod a spin if you are looking to have less weird looking structures in a floating island world!
And yes, you may use this mod in modpacks. And this mod also can work solely server-side as well which means vanilla clients can still connect with my mod on server.