That is why I chose the word Floor, which is a synonym to layer...
I totally agree on the terminology here.
I just finished what I think to be the easiest part, which is to replace to list view into a tree view in the utiLITI as above
In general, we've thought about extending the plain list to a tree for another reason as well: we're planning to provide the possibility to better organize the maps with "folders".
I'm honestly not sure yet whether the concept of floors is general enough to be covered in the editor. I think we should first discover and discuss the different kinds of "child-maps" that might exist. I remember that we had a "cave-system" in the original LITI game that was realized very similarly to your use-case. At that time we solved this with an additional layer that blocked off vision and that wouldn't be rendered anymore when the player entered the cave. Maybe there are even further examples of "child-maps". We should investigate this first and then plan an implementation accordingly to suit the most cases.
Before pushing a new branch on GitHub so you can have a look,
For the aforementioned reasons, I'd suggest to first finish the conceptualization and discussion on what we actually want in the engine. The engine should provide a solution for a general problem and I think that the floor concept might be too specific.
Do you think it would be fair to render two or more .tmx maps at the same time instead?
Right now the engine is not prepared to render multiple environments at a time and I even think that this would interfere with some of the engines API and design decisions (i.e. only one
Environment can be loaded/managed at a time).