Better nanofrost

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

@@ -175,53 +175,71 @@
 	name = "nanofrost smoke"
 	color = "#B2FFFF"
 	opacity = FALSE
+	var/spread_range = 6
+	lifetime = 0.5 SECONDS_TO_LIFE_CYCLES
 
 /datum/effect_system/smoke_spread/freezing
 	effect_type = /obj/effect/particle_effect/smoke/freezing
-	var/blast = FALSE
-
-/datum/effect_system/smoke_spread/freezing/proc/Chilled(atom/A)
-	if(issimulatedturf(A))
-		var/turf/simulated/T = A
-		if(!T.blocks_air)
-			var/datum/milla_safe/smoke_spread_chill/milla = new()
-			milla.invoke_async(src, T)
-		for(var/obj/machinery/atmospherics/unary/vent_pump/V in T)
-			if(!isnull(V.welded) && !V.welded) //must be an unwelded vent pump.
-				V.welded = TRUE
-				V.update_icon()
-				V.visible_message("<span class='danger'>[V] was frozen shut!</span>")
-		for(var/obj/machinery/atmospherics/unary/vent_scrubber/U in T)
-			if(!isnull(U.welded) && !U.welded) //must be an unwelded vent scrubber.
-				U.welded = TRUE
-				U.update_icon()
-				U.visible_message("<span class='danger'>[U] was frozen shut!</span>")
-		for(var/mob/living/L in T)
-			L.ExtinguishMob()
-		for(var/obj/item/Item in T)
-			Item.extinguish()
-
-/datum/milla_safe/smoke_spread_chill
-
-/datum/milla_safe/smoke_spread_chill/on_run(datum/effect_system/smoke_spread/smoke, turf/T)
+
+/obj/effect/particle_effect/smoke/freezing/process()
+	. = ..()
+	var/turf/T = get_turf(src)
+	if(!istype(T))
+		return
+
+	for(var/obj/machinery/atmospherics/unary/vent_pump/V in T)
+		if(!isnull(V.welded) && !V.welded) //must be an unwelded vent pump.
+			V.welded = TRUE
+			V.update_icon()
+			V.visible_message("<span class='danger'>[V] was frozen shut!</span>")
+	for(var/obj/machinery/atmospherics/unary/vent_scrubber/U in T)
+		if(!isnull(U.welded) && !U.welded) //must be an unwelded vent scrubber.
+			U.welded = TRUE
+			U.update_icon()
+			U.visible_message("<span class='danger'>[U] was frozen shut!</span>")
+	for(var/mob/living/L in T)
+		L.ExtinguishMob()
+	for(var/obj/item/Item in T)
+		Item.extinguish()
+
+	var/datum/milla_safe/nanofrost_extinguish/milla = new()
+	milla.invoke_async(src, T)
+
+/datum/milla_safe/nanofrost_extinguish/on_run(obj/effect/particle_effect/smoke/freezing/smoke, turf/T)
+	if(!istype(T))
+		return
 	var/datum/gas_mixture/env = get_turf_air(T)
-	if(get_dist(T, smoke) < 2) // Otherwise we'll get silliness like people using Nanofrost to kill people through walls with cold air
-		env.set_temperature(2)
-	for(var/obj/effect/hotspot/H in T)
+	for(var/obj/effect/hotspot/fake/H in T)
 		qdel(H)
-		if(env.toxins())
-			env.set_nitrogen(env.nitrogen() + env.toxins())
-			env.set_toxins(0)
-
-/datum/effect_system/smoke_spread/freezing/set_up(amount = 5, only_cardinals = FALSE, source, desired_direction, datum/reagents/chemicals, blasting = FALSE)
-	..()
-	blast = blasting
-
-/datum/effect_system/smoke_spread/freezing/start()
-	if(blast)
-		for(var/turf/T in RANGE_TURFS(2, location))
-			Chilled(T)
-	..()
+
+	if(env.fuel_burnt() == 0)
+		return
+
+	env.set_temperature(2)
+	env.set_nitrogen(env.nitrogen() + env.toxins())
+	env.set_toxins(0)
+
+	if(smoke.spread_range <= 0 || smoke.lifetime > 0)
+		return
+
+	// Spread the smoke, up to spread_range.
+	for(var/direction in list(NORTH, SOUTH, EAST, WEST))
+		var/turf/neighbor = get_step(T, direction)
+		if(isnull(neighbor))
+			continue
+		if(neighbor.density)
+			continue
+		var/has_nanofrost = FALSE
+		for(var/datum/effect_system/smoke_spread/freezing in neighbor)
+			has_nanofrost = TRUE
+			break
+		if(has_nanofrost)
+			continue
+		if(prob(50))
+			continue
+
+		var/obj/effect/particle_effect/smoke/freezing/new_smoke = new(neighbor)
+		new_smoke.spread_range = smoke.spread_range - 1
 
 /////////////////////////////////////////////
 // Sleep smoke

code/game/objects/items/weapons/tanks/watertank.dm

@@ -328,7 +328,7 @@
 
 /obj/effect/nanofrost_container/proc/Smoke()
 	var/datum/effect_system/smoke_spread/freezing/S = new
-	S.set_up(amount = 6, only_cardinals = FALSE, source = loc, desired_direction = null, chemicals = null, blasting = TRUE)
+	S.set_up(amount = 6, only_cardinals = FALSE, source = loc)
 	S.start()
 	new /obj/effect/decal/cleanable/flour/nanofrost(get_turf(src))
 	playsound(src, 'sound/effects/bamf.ogg', 100, TRUE)