Makes atmos treat atmos_adjacent_turfs as a list

code/modules/atmospherics/environmental/LINDA_system.dm

@@ -67,47 +67,38 @@
 		var/turf/T = get_step(src, direction)
 		if(!istype(T))
 			continue
-		var/counterdir = get_dir(T, src)
 		if(CanAtmosPass(T))
 			atmos_adjacent_turfs_amount += 1
-			atmos_adjacent_turfs |= direction
-			if(!(T.atmos_adjacent_turfs & counterdir))
+			atmos_adjacent_turfs |= T
+			if(!(src in T.atmos_adjacent_turfs))
 				T.atmos_adjacent_turfs_amount += 1
-			T.atmos_adjacent_turfs |= counterdir
+			T.atmos_adjacent_turfs |= src
 		else
-			atmos_adjacent_turfs &= ~direction
-			if(T.atmos_adjacent_turfs & counterdir)
+			atmos_adjacent_turfs -= T
+			if(src in T.atmos_adjacent_turfs)
 				T.atmos_adjacent_turfs_amount -= 1
-			T.atmos_adjacent_turfs &= ~counterdir
+			T.atmos_adjacent_turfs -= src
 
 //returns a list of adjacent turfs that can share air with this one.
 //alldir includes adjacent diagonal tiles that can share
 //	air with both of the related adjacent cardinal tiles
 /turf/proc/GetAtmosAdjacentTurfs(alldir = 0)
 	if (!istype(src, /turf/simulated))
 		return list()
-
-	var/adjacent_turfs = list()
-
-	var/turf/simulated/curloc = src
-	for (var/direction in cardinal)
-		if(!(curloc.atmos_adjacent_turfs & direction))
-			continue
-
-		var/turf/simulated/S = get_step(curloc, direction)
-		if (istype(S))
-			adjacent_turfs += S
+
+	var/adjacent_turfs = atmos_adjacent_turfs.Copy()
 	if (!alldir)
-		return adjacent_turfs
+		return adjacent_turfs()
+	var/turf/simulated/curloc = src
 
 	for (var/direction in diagonals)
 		var/matchingDirections = 0
 		var/turf/simulated/S = get_step(curloc, direction)
 
 		for (var/checkDirection in cardinal)
-			if(!(S.atmos_adjacent_turfs & checkDirection))
-				continue
 			var/turf/simulated/checkTurf = get_step(S, checkDirection)
+			if(!(checkTurf in S.atmos_adjacent_turfs))
+				continue
 
 			if (checkTurf in adjacent_turfs)
 				matchingDirections++
@@ -190,4 +181,4 @@ var/const/SPAWN_AIR = 256
 		new_gases["n2"][MOLES] += MOLES_N2STANDARD * amount
 
 	air.merge(G)
-	SSair.add_to_active(src, 0)
+	SSair.add_to_active(src, 0)