What does it mean to set a flag?
Right now my game randomizes the layout of my dungeon room by randomly selecting a pre-designed layout, which has its own dedicated layer, and setting the layer to visible. Unfortunately, it doesn't make the objects solid, obviously, so I need to find a way to (hopefully easily) make all objects in the visible layer solid too. Also, for the purpose of saving memory, I should probably delete all the other invisible objects as well. So... is there a trick for deleting the contents of an entire layer all at once?
So that's two questions:
1. Make all objects on a single layer visible
2. Make all objects on the other random layers deleted