isActive: indicates if the tile is animated (eg: bonfire has fire or is extinguished)
isSupported: layer2 tile checks beneath it (layer1) to see if there's something to hold it up on that layer (sanity check)
Dunno how to handle the isActive set-on-save. I saw there was an isActive flag in my plaza, assumedly left there from a radio or something. NHSE does not change flag state at this time.
Preallocate the terrain-building objects and reuse
changed:
- grid alternates with a slightly-darker to help indicate the larger 2x2 tile grid.
- put plaza & buildings behind the gridlines
Extracts logic from the building & terrain & field item editors for reuse / separation of concerns
Have FieldItemEditor select between Items & Terrain so that you can change the popup menu mode (view set delete)
Not sure how I want to show the terrain names...
