I've just committed the building snapping feature. I'd like to here some feedback: does it behave like you expect, would you like to change something (like adding an option to enable it by default)? To use the building snapping you need to select a building, press Ctrl and move your mouse. When a preview of the new building is near to other structures it`s trying to snap to their edges (while Ctrl is pressed).   Snapping (1).mp4