Lets play with our imagination
The same water pattern showed up again (yes, I recognized it in-game from a year-and-a-half-old post), and it appears that the destructible walls of the castle appear in the same pattern. The background is different of course, but I suppose that castles have a number of preset layouts they go through?
(ppe btw)
Yup, I remember @Male writing a realm detection algorithm, and he had to automatically remove setpieces so that he could run the pixel recognition part. There are a few variants of the setpieces, and itās always one of those variants, potentially rotated. The holes in the castle floor actually let through some of the map that was covered by the setpiece.
The smallest setpieces (that show you most of the map) are ent groves and ghost king keeps.
He did quite some work improving on the maps on the wiki by replacing bulkier structures with those for the sake of the algorithm.
On topic: