hmm… so my interpretation is white = void and pink = dungeon.
so the cell (a 3x3) that’s full-pink = inner cell/floor. a full white cell is void.
The north wall (green) states “select me if I am dungeon and am surrounded by dungeon cell on W,SW,S,SE & E as well as having void to the NW,N & NE”
The south wall is essentially the opposite; void to the SW,S,SE and dungeon everywhere else.
Blue is for a dungeon cell surrounded by void to the full north and south.
The reason I do it like this (and it’s my interpretation of it) is because when you fill in any shape it calcs all the walls out correctly… this includes the code I have to fill in the map by setting all the “dungeon” cells. Its very simple to do this approach in code
However it sounds like in need two layers - one to fill in just the edges/corners on an upper layer and another under it for the inner layers for the floor? Or maybe floor is everything and the “under wall” tiles are partially transparent?