The passability byte in the old map format
0 = Can?t walk, can?t build
150 = Can walk, can?t build
255 = Can walk, can build
?
Well it's a lie. Ok not really a lie, but it's misinformation. Untrue. Nonsense.
Especially the 150, which is a completely random number that doesn't make sense in any way. 127 or 128 would, but not 150. Maybe it just happened to work.
It's a bit switch. We haven't figured it all out yet, but there are bits for "walkable" "buildable" "farmable" and some weird things related to trees.
So far:
bit 0 = walkable
bit 1 = unknown??
bit 2 = buildable
bit 3 = farmable
bit 4 = south west of tree*
bit 5 = north west of tree*
bit 6 = north east of tree*
bit 7 = south east of tree*
* doesn't seem to make much sense does it? could be something about diagonal passability.
We'll keep you posted.