turns the baseturf var into a part time list (#33705)

code/game/objects/effects/effect_system/effects_foam.dm

@@ -76,7 +76,7 @@
 	if(metal)
 		var/turf/T = get_turf(src)
 		if(isspaceturf(T)) //Block up any exposed space
-			T.ChangeTurf(/turf/open/floor/plating/foam)
+			T.PlaceOnTop(/turf/open/floor/plating/foam)
 		for(var/direction in GLOB.cardinals)
 			var/turf/cardinal_turf = get_step(T, direction)
 			if(get_area(cardinal_turf) != get_area(T)) //We're at an area boundary, so let's block off this turf!

code/game/objects/effects/spawners/vaultspawner.dm

@@ -20,9 +20,9 @@
 		for(var/j = lowBoundY,j<=hiBoundY,j++)
 			var/turf/T = locate(i,j,z)
 			if(i == lowBoundX || i == hiBoundX || j == lowBoundY || j == hiBoundY)
-				T.ChangeTurf(/turf/closed/wall/vault)
+				T.PlaceOnTop(/turf/closed/wall/vault)
 			else
-				T.ChangeTurf(/turf/open/floor/vault)
+				T.PlaceOnTop(/turf/open/floor/vault)
 			T.icon_state = "[type]vault"
 
 	qdel(src)

code/game/objects/items/melee/misc.dm

@@ -275,13 +275,14 @@
 		consume_turf(target)
 
 /obj/item/melee/supermatter_sword/proc/consume_turf(turf/T)
-	if(istype(T, T.baseturf))
-		return //Can't void the void, baby!
+	var/oldtype = T.type
+	var/turf/newT = T.ScrapeAway()
+	if(newT.type == oldtype)
+		return
 	playsound(T, 'sound/effects/supermatter.ogg', 50, 1)
 	T.visible_message("<span class='danger'>[T] smacks into [src] and rapidly flashes to ash.</span>",\
 	"<span class='italics'>You hear a loud crack as you are washed with a wave of heat.</span>")
 	shard.Consume()
-	T.ChangeTurf(T.baseturf)
 	T.CalculateAdjacentTurfs()
 
 /obj/item/melee/supermatter_sword/add_blood(list/blood_dna)

code/game/objects/structures/false_walls.dm

@@ -85,7 +85,7 @@
 
 /obj/structure/falsewall/proc/ChangeToWall(delete = 1)
 	var/turf/T = get_turf(src)
-	T.ChangeTurf(walltype)
+	T.PlaceOnTop(walltype)
 	if(delete)
 		qdel(src)
 	return T

code/game/objects/structures/girders.dm

@@ -86,7 +86,7 @@
 					S.use(5)
 					to_chat(user, "<span class='notice'>You add the plating.</span>")
 					var/turf/T = get_turf(src)
-					T.ChangeTurf(/turf/closed/wall/mineral/iron)
+					T.PlaceOnTop(/turf/closed/wall/mineral/iron)
 					transfer_fingerprints_to(T)
 					qdel(src)
 				return
@@ -120,7 +120,7 @@
 					S.use(2)
 					to_chat(user, "<span class='notice'>You add the plating.</span>")
 					var/turf/T = get_turf(src)
-					T.ChangeTurf(/turf/closed/wall)
+					T.PlaceOnTop(/turf/closed/wall)
 					transfer_fingerprints_to(T)
 					qdel(src)
 				return
@@ -150,7 +150,7 @@
 						S.use(1)
 						to_chat(user, "<span class='notice'>You fully reinforce the wall.</span>")
 						var/turf/T = get_turf(src)
-						T.ChangeTurf(/turf/closed/wall/r_wall)
+						T.PlaceOnTop(/turf/closed/wall/r_wall)
 						transfer_fingerprints_to(T)
 						qdel(src)
 					return
@@ -194,7 +194,7 @@
 					S.use(2)
 					to_chat(user, "<span class='notice'>You add the plating.</span>")
 					var/turf/T = get_turf(src)
-					T.ChangeTurf(text2path("/turf/closed/wall/mineral/[M]"))
+					T.PlaceOnTop(text2path("/turf/closed/wall/mineral/[M]"))
 					transfer_fingerprints_to(T)
 					qdel(src)
 				return
@@ -397,7 +397,7 @@
 			user.visible_message("<span class='notice'>[user] plates [src] with runed metal.</span>", "<span class='notice'>You construct a runed wall.</span>")
 			R.use(1)
 			var/turf/T = get_turf(src)
-			T.ChangeTurf(/turf/closed/wall/mineral/cult)
+			T.PlaceOnTop(/turf/closed/wall/mineral/cult)
 			qdel(src)
 
 	else
@@ -424,7 +424,7 @@
 	switch(passed_mode)
 		if(RCD_FLOORWALL)
 			to_chat(user, "<span class='notice'>You finish a wall.</span>")
-			T.ChangeTurf(/turf/closed/wall)
+			T.PlaceOnTop(/turf/closed/wall)
 			qdel(src)
 			return TRUE
 		if(RCD_DECONSTRUCT)