[MIRROR] update_appearance (#3508)

* update_appearance

* a

* a

Co-authored-by: TemporalOroboros <TemporalOroboros@gmail.com>
Co-authored-by: Gandalf2k15 <jzo123@hotmail.com>

code/modules/NTNet/relays.dm

@@ -59,10 +59,8 @@
 
 
 /obj/machinery/ntnet_relay/update_icon_state()
-	if(is_operational)
-		icon_state = "bus"
-	else
-		icon_state = "bus_off"
+	icon_state = "bus[is_operational ? null : "_off"]"
+	return ..()
 
 /obj/machinery/ntnet_relay/process(delta_time)
 	if(is_operational)
@@ -70,7 +68,7 @@
 	else
 		use_power = IDLE_POWER_USE
 
-	update_icon()
+	update_appearance()
 
 	if(dos_overload > 0)
 		dos_overload = max(0, dos_overload - dos_dissipate * delta_time)
@@ -78,12 +76,12 @@
 	// If DoS traffic exceeded capacity, crash.
 	if((dos_overload > dos_capacity) && !dos_failure)
 		set_dos_failure(TRUE)
-		update_icon()
+		update_appearance()
 		SSnetworks.add_log("Quantum relay switched from normal operation mode to overload recovery mode.")
 	// If the DoS buffer reaches 0 again, restart.
 	if((dos_overload == 0) && dos_failure)
 		set_dos_failure(FALSE)
-		update_icon()
+		update_appearance()
 		SSnetworks.add_log("Quantum relay switched from overload recovery mode to normal operation mode.")
 	..()
 
@@ -109,13 +107,13 @@
 		if("restart")
 			dos_overload = 0
 			set_dos_failure(FALSE)
-			update_icon()
+			update_appearance()
 			SSnetworks.add_log("Quantum relay manually restarted from overload recovery mode to normal operation mode.")
 			return TRUE
 		if("toggle")
 			set_relay_enabled(!relay_enabled)
 			SSnetworks.add_log("Quantum relay manually [relay_enabled ? "enabled" : "disabled"].")
-			update_icon()
+			update_appearance()
 			return TRUE
 
 /obj/machinery/ntnet_relay/Initialize()

code/modules/admin/verbs/debug.dm

@@ -216,7 +216,7 @@ But you can call procs that are of type /mob/living/carbon/human/proc/ for that
 					var/obj/item/storage/wallet/W = worn
 					W.front_id = id
 					id.forceMove(W)
-					W.update_icon()
+					W.update_appearance()
 			else
 				H.equip_to_slot(id,ITEM_SLOT_ID)
 

code/modules/admin/verbs/manipulate_organs.dm

@@ -71,4 +71,4 @@
 				var/obj/item/implantcase/case = new(get_turf(C))
 				case.imp = I
 				I.forceMove(case)
-				case.update_icon()
+				case.update_appearance()

code/modules/antagonists/abductor/equipment/abduction_gear.dm

@@ -488,9 +488,10 @@ Congratulations! You are now trained for invasive xenobiology research!"}
 	if(!turned_on)
 		toggle_on(user)
 	to_chat(usr, "<span class='notice'>You switch the baton to [txt] mode.</span>")
-	update_icon()
+	update_appearance()
 
 /obj/item/melee/baton/abductor/update_icon_state()
+	. = ..()
 	switch(mode)
 		if(BATON_STUN)
 			icon_state = "wonderprodStun"

code/modules/antagonists/abductor/machinery/experiment.dm

@@ -183,7 +183,5 @@
 	return
 
 /obj/machinery/abductor/experiment/update_icon_state()
-	if(state_open)
-		icon_state = "experiment-open"
-	else
-		icon_state = "experiment"
+	icon_state = "experiment[state_open ? "-open" : null]"
+	return ..()

code/modules/antagonists/blob/blobstrains/_blobstrain.dm

@@ -95,7 +95,7 @@ GLOBAL_LIST_INIT(valid_blobstrains, subtypesof(/datum/blobstrain) - list(/datum/
 	for(var/obj/structure/blob/B as anything in overmind.all_blobs)
 		B.max_integrity *= max_structure_health_multiplier
 		B.obj_integrity *= max_structure_health_multiplier
-		B.update_icon()
+		B.update_appearance()
 
 	for(var/mob/living/simple_animal/hostile/blob/BM as anything in overmind.blob_mobs)
 		BM.maxHealth *= max_mob_health_multiplier

code/modules/antagonists/blob/blobstrains/replicating_foam.dm

@@ -17,7 +17,7 @@
 		var/obj/structure/blob/newB = B.expand(null, null, 0)
 		if(newB)
 			newB.obj_integrity = B.obj_integrity - damage
-			newB.update_icon()
+			newB.update_appearance()
 	return ..()
 
 

code/modules/antagonists/blob/overmind.dm

@@ -64,7 +64,7 @@ GLOBAL_LIST_EMPTY(blob_nodes)
 	set_strain(BS)
 	color = blobstrain.complementary_color
 	if(blob_core)
-		blob_core.update_icon()
+		blob_core.update_appearance()
 	SSshuttle.registerHostileEnvironment(src)
 	. = ..()
 	START_PROCESSING(SSobj, src)
@@ -186,7 +186,7 @@ GLOBAL_LIST_EMPTY(blob_nodes)
 		var/obj/structure/blob/B = BL
 		if(B && B.overmind == src)
 			B.overmind = null
-			B.update_icon() //reset anything that was ours
+			B.update_appearance() //reset anything that was ours
 	for(var/BLO in blob_mobs)
 		var/mob/living/simple_animal/hostile/blob/BM = BLO
 		if(BM)

code/modules/antagonists/blob/powers.dm

@@ -55,7 +55,7 @@
 		core.overmind = src
 		blobs_legit += src
 		blob_core = core
-		core.update_icon()
+		core.update_appearance()
 	update_health_hud()
 	placed = TRUE
 	announcement_time = world.time + OVERMIND_ANNOUNCEMENT_MAX_TIME
@@ -146,7 +146,7 @@
 	if(LAZYLEN(candidates)) //if we got at least one candidate, they're a blobbernaut now.
 		B.max_integrity = initial(B.max_integrity) * 0.25 //factories that produced a blobbernaut have much lower health
 		B.obj_integrity = min(B.obj_integrity, B.max_integrity)
-		B.update_icon()
+		B.update_appearance()
 		B.visible_message("<span class='warning'><b>The blobbernaut [pick("rips", "tears", "shreds")] its way out of the factory blob!</b></span>")
 		playsound(B.loc, 'sound/effects/splat.ogg', 50, TRUE)
 		var/mob/living/simple_animal/hostile/blob/blobbernaut/blobber = new /mob/living/simple_animal/hostile/blob/blobbernaut(get_turf(B))

code/modules/antagonists/blob/structures/_blob.dm

@@ -41,7 +41,7 @@
 			overmind.blobs_legit += src
 	GLOB.blobs += src //Keep track of the blob in the normal list either way
 	setDir(pick(GLOB.cardinals))
-	update_icon()
+	update_appearance()
 	if(atmosblock)
 		air_update_turf(TRUE, TRUE)
 	ConsumeTile()
@@ -86,6 +86,7 @@
 	return !atmosblock
 
 /obj/structure/blob/update_icon() //Updates color based on overmind color if we have an overmind.
+	. = ..()
 	if(overmind)
 		add_atom_colour(overmind.blobstrain.color, FIXED_COLOUR_PRIORITY)
 	else
@@ -97,7 +98,7 @@
 		if(COOLDOWN_FINISHED(src, heal_timestamp))
 			obj_integrity = min(max_integrity, obj_integrity+health_regen)
 			COOLDOWN_START(src, heal_timestamp, 20)
-		update_icon()
+		update_appearance()
 		COOLDOWN_START(src, pulse_timestamp, 10)
 		return TRUE//we did it, we were pulsed!
 	return FALSE //oh no we failed
@@ -161,7 +162,7 @@
 		if(T.Enter(B,src)) //NOW we can attempt to move into the tile
 			B.density = initial(B.density)
 			B.forceMove(T)
-			B.update_icon()
+			B.update_appearance()
 			if(B.overmind && expand_reaction)
 				B.overmind.blobstrain.expand_reaction(src, B, T, controller)
 			return B
@@ -267,7 +268,7 @@
 /obj/structure/blob/take_damage(damage_amount, damage_type = BRUTE, damage_flag = 0, sound_effect = 1, attack_dir)
 	. = ..()
 	if(. && obj_integrity > 0)
-		update_icon()
+		update_appearance()
 
 /obj/structure/blob/obj_destruction(damage_flag)
 	if(overmind)
@@ -279,7 +280,7 @@
 		CRASH("change_to(): invalid type for blob")
 	var/obj/structure/blob/B = new type(src.loc, controller)
 	B.creation_action()
-	B.update_icon()
+	B.update_appearance()
 	B.setDir(dir)
 	qdel(src)
 	return B
@@ -321,23 +322,30 @@
 		return "Currently weak to brute damage."
 	return "N/A"
 
-/obj/structure/blob/normal/update_icon()
-	..()
+/obj/structure/blob/normal/update_name()
+	. = ..()
+	name = "[(obj_integrity <= 15) ? "fragile " : (overmind ? null : "dead ")][initial(name)]"
+
+/obj/structure/blob/normal/update_desc()
+	. = ..()
 	if(obj_integrity <= 15)
-		icon_state = "blob_damaged"
-		name = "fragile blob"
 		desc = "A thin lattice of slightly twitching tendrils."
+	else if(overmind)
+		desc = "A thick wall of writhing tendrils."
+	else
+		desc = "A thick wall of lifeless tendrils."
+
+/obj/structure/blob/normal/update_icon_state()
+	icon_state = "blob[(obj_integrity <= 15) ? "_damaged" : null]"
+
+	/// - [] TODO: Move this elsewhere
+	if(obj_integrity <= 15)
 		brute_resist = BLOB_BRUTE_RESIST
 	else if (overmind)
-		icon_state = "blob"
-		name = "blob"
-		desc = "A thick wall of writhing tendrils."
 		brute_resist = BLOB_BRUTE_RESIST * 0.5
 	else
-		icon_state = "blob"
-		name = "dead blob"
-		desc = "A thick wall of lifeless tendrils."
 		brute_resist = BLOB_BRUTE_RESIST * 0.5
+	return ..()
 
 /obj/structure/blob/special // Generic type for nodes/factories/cores/resource
 	// Core and node vars: claiming, pulsing and expanding
@@ -386,7 +394,7 @@
 		var/obj/structure/blob/B = L
 		if(!B.overmind && prob(30))
 			B.overmind = pulsing_overmind //reclaim unclaimed, non-core blobs.
-			B.update_icon()
+			B.update_appearance()
 		var/distance = get_dist(get_turf(src), get_turf(B))
 		var/expand_probablity = max(20 - distance * 8, 1)
 		if(B.Adjacent(src))

code/modules/antagonists/blob/structures/core.dm

@@ -21,34 +21,37 @@
 	GLOB.blob_cores += src
 	START_PROCESSING(SSobj, src)
 	AddElement(/datum/element/point_of_interest)
-	update_icon() //so it atleast appears
+	update_appearance() //so it atleast appears
 	if(!placed && !overmind)
 		return INITIALIZE_HINT_QDEL
 	if(overmind)
 		overmind.blobstrain.on_gain()
-		update_icon()
+		update_appearance()
 	. = ..()
 
-/obj/structure/blob/special/core/scannerreport()
-	return "Directs the blob's expansion, gradually expands, and sustains nearby blob spores and blobbernauts."
-
-/obj/structure/blob/special/core/update_icon()
-	cut_overlays()
-	color = null
-	var/mutable_appearance/blob_overlay = mutable_appearance('icons/mob/blob.dmi', "blob")
-	if(overmind)
-		blob_overlay.color = overmind.blobstrain.color
-	add_overlay(blob_overlay)
-	add_overlay(mutable_appearance('icons/mob/blob.dmi', "blob_core_overlay"))
-
 /obj/structure/blob/special/core/Destroy()
 	GLOB.blob_cores -= src
 	if(overmind)
 		overmind.blob_core = null
-	overmind = null
+		overmind = null
 	STOP_PROCESSING(SSobj, src)
 	return ..()
 
+/obj/structure/blob/special/core/scannerreport()
+	return "Directs the blob's expansion, gradually expands, and sustains nearby blob spores and blobbernauts."
+
+/obj/structure/blob/special/core/update_overlays()
+	. = ..()
+	var/mutable_appearance/blob_overlay = mutable_appearance('icons/mob/blob.dmi', "blob")
+	if(overmind)
+		blob_overlay.color = overmind.blobstrain.color
+	. += blob_overlay
+	. += mutable_appearance('icons/mob/blob.dmi', "blob_core_overlay")
+
+/obj/structure/blob/special/core/update_icon()
+	color = null
+	return ..()
+
 /obj/structure/blob/special/core/ex_act(severity, target)
 	var/damage = 50 - 10 * severity //remember, the core takes half brute damage, so this is 20/15/10 damage based on severity
 	take_damage(damage, BRUTE, BOMB, 0)

code/modules/antagonists/blob/structures/node.dm

@@ -24,13 +24,16 @@
 	return "Gradually expands and sustains nearby blob spores and blobbernauts."
 
 /obj/structure/blob/special/node/update_icon()
-	cut_overlays()
 	color = null
+	return ..()
+
+/obj/structure/blob/special/node/update_overlays()
+	. = ..()
 	var/mutable_appearance/blob_overlay = mutable_appearance('icons/mob/blob.dmi', "blob")
 	if(overmind)
 		blob_overlay.color = overmind.blobstrain.color
-	add_overlay(blob_overlay)
-	add_overlay(mutable_appearance('icons/mob/blob.dmi', "blob_node_overlay"))
+	. += blob_overlay
+	. += mutable_appearance('icons/mob/blob.dmi', "blob_node_overlay")
 
 /obj/structure/blob/special/node/creation_action()
 	if(overmind)

code/modules/antagonists/blob/structures/shield.dm

@@ -20,20 +20,23 @@
 /obj/structure/blob/shield/core // Automatically generated by the core
 	point_return = 0
 
-/obj/structure/blob/shield/update_icon()
-	..()
-	if(obj_integrity < max_integrity * 0.5)
-		icon_state = "[initial(icon_state)]_damaged"
-		name = "weakened [initial(name)]"
-		desc = "[damaged_desc]"
-		atmosblock = FALSE
-		air_update_turf(TRUE, FALSE)
-	else
-		icon_state = initial(icon_state)
-		name = initial(name)
-		desc = initial(desc)
-		atmosblock = TRUE
-		air_update_turf(TRUE, TRUE)
+/obj/structure/blob/shield/update_name(updates)
+	. = ..()
+	name = "[(obj_integrity < (max_integrity * 0.5)) ? "weakened " : null][initial(name)]"
+
+/obj/structure/blob/shield/update_desc(updates)
+	. = ..()
+	desc = (obj_integrity < (max_integrity * 0.5)) ? "[damaged_desc]" : initial(desc)
+
+/obj/structure/blob/shield/take_damage(damage_amount, damage_type, damage_flag, sound_effect, attack_dir)
+	. = ..()
+	if(. && obj_integrity > 0)
+		atmosblock = obj_integrity < (max_integrity * 0.5)
+		air_update_turf(TRUE, atmosblock)
+
+/obj/structure/blob/shield/update_icon_state()
+	icon_state = "[initial(icon_state)][(obj_integrity < (max_integrity * 0.5)) ? "_damaged" : null]"
+	return ..()
 
 /obj/structure/blob/shield/reflective
 	name = "reflective blob"

code/modules/antagonists/cult/cult_items.dm

@@ -372,6 +372,7 @@
 
 /obj/item/sharpener/cult/update_icon_state()
 	icon_state = "cult_sharpener[(uses == 0) ? "_used" : ""]"
+	return ..()
 
 /obj/item/clothing/suit/hooded/cultrobes/cult_shield
 	name = "empowered cultist armor"
@@ -639,8 +640,7 @@
 	name = "bloody halberd"
 	desc = "A halberd with a volatile axehead made from crystallized blood. It seems linked to its creator. And, admittedly, more of a poleaxe than a halberd."
 	icon_state = "occultpoleaxe0"
-	inhand_icon_state = "occultpoleaxe0"
-	base_icon_state = "occultpoleaxe0"
+	base_icon_state = "occultpoleaxe"
 	w_class = WEIGHT_CLASS_HUGE
 	force = 17
 	throwforce = 40
@@ -663,7 +663,7 @@
 /obj/item/melee/cultblade/halberd/ComponentInitialize()
 	. = ..()
 	AddComponent(/datum/component/butchering, 100, 90)
-	AddComponent(/datum/component/two_handed, force_unwielded=17, force_wielded=24)
+	AddComponent(/datum/component/two_handed, force_unwielded=17, force_wielded=24, icon_wielded = "[base_icon_state]1")
 
 /// triggered on wield of two handed item
 /obj/item/melee/cultblade/halberd/proc/on_wield(obj/item/source, mob/user)
@@ -678,12 +678,8 @@
 	wielded = FALSE
 
 /obj/item/melee/cultblade/halberd/update_icon_state()
-	if(wielded)
-		icon_state = "occultpoleaxe1"
-		inhand_icon_state = "occultpoleaxe1"
-	else
-		icon_state = "[base_icon_state]"
-		inhand_icon_state = "[base_icon_state]"
+	icon_state = "[base_icon_state]0"
+	return ..()
 
 /obj/item/melee/cultblade/halberd/Destroy()
 	if(halberd_act)

code/modules/antagonists/cult/cult_structures.dm

@@ -63,10 +63,11 @@
 	. = ..()
 	if(isnull(.))
 		return
-	update_icon()
+	update_appearance()
 
 /obj/structure/destructible/cult/update_icon_state()
 	icon_state = "[initial(icon_state)][anchored ? null : "_off"]"
+	return ..()
 
 /obj/structure/destructible/cult/attackby(obj/I, mob/user, params)
 	if(istype(I, /obj/item/melee/cultblade/dagger) && iscultist(user))

code/modules/antagonists/eldritch_cult/eldritch_book.dm

@@ -135,7 +135,7 @@
 					charge -= initial(EK.cost)
 					return TRUE
 
-	update_icon() // Not applicable to all objects.
+	update_appearance() // Not applicable to all objects.
 
 /obj/item/forbidden_book/ui_close(mob/user)
 	flick("book_closing",src)

code/modules/antagonists/eldritch_cult/eldritch_magic.dm

@@ -630,7 +630,7 @@
 	pixel_y = rand(-6,6)
 	pixel_x = rand(-6,6)
 	icon_state = "small_rune_[rand(12)]"
-	update_icon()
+	update_appearance()
 
 /obj/effect/proc_holder/spell/cone/staggered/entropic_plume
 	name = "Entropic Plume"

code/modules/antagonists/eldritch_cult/eldritch_structures.dm

@@ -3,6 +3,7 @@
 	desc = "Immortalized cast iron, the steel-like teeth holding it in place, it's vile extract has the power of rebirthing things, remaking them from the very beginning."
 	icon = 'icons/obj/eldritch.dmi'
 	icon_state = "crucible"
+	base_icon_state = "crucible"
 	anchored = FALSE
 	density = TRUE
 	///How much mass this currently holds
@@ -100,11 +101,8 @@
 	update_icon_state()
 
 /obj/structure/eldritch_crucible/update_icon_state()
-	. = ..()
-	if(current_mass == max_mass)
-		icon_state = "crucible"
-	else
-		icon_state = "crucible_empty"
+	icon_state = "[base_icon_state][(current_mass == max_mass) ? null : "_empty"]"
+	return ..()
 
 /obj/structure/trap/eldritch
 	name = "elder carving"

code/modules/antagonists/nukeop/equipment/nuclearbomb.dm

@@ -37,7 +37,7 @@
 	GLOB.nuke_list += src
 	core = new /obj/item/nuke_core(src)
 	STOP_PROCESSING(SSobj, core)
-	update_icon()
+	update_appearance()
 	AddElement(/datum/element/point_of_interest)
 	previous_level = get_security_level()
 
@@ -108,7 +108,7 @@
 				if(I.use_tool(src, user, 60, volume=100))
 					deconstruction_state = NUKESTATE_UNSCREWED
 					to_chat(user, "<span class='notice'>You remove the screws from [src]'s front panel.</span>")
-					update_icon()
+					update_appearance()
 				return
 
 		if(NUKESTATE_PANEL_REMOVED)
@@ -119,7 +119,7 @@
 				if(I.use_tool(src, user, 80, volume=100, amount=1))
 					to_chat(user, "<span class='notice'>You cut [src]'s inner plate.</span>")
 					deconstruction_state = NUKESTATE_WELDED
-					update_icon()
+					update_appearance()
 				return
 		if(NUKESTATE_CORE_EXPOSED)
 			if(istype(I, /obj/item/nuke_core_container))
@@ -129,7 +129,7 @@
 					if(core_box.load(core, user))
 						to_chat(user, "<span class='notice'>You load the plutonium core into [core_box].</span>")
 						deconstruction_state = NUKESTATE_CORE_REMOVED
-						update_icon()
+						update_appearance()
 						core = null
 					else
 						to_chat(user, "<span class='warning'>You fail to load the plutonium core into [core_box]. [core_box] has already been used!</span>")
@@ -143,7 +143,7 @@
 					to_chat(user, "<span class='notice'>You repair [src]'s inner metal plate. The radiation is contained.</span>")
 					deconstruction_state = NUKESTATE_PANEL_REMOVED
 					STOP_PROCESSING(SSobj, core)
-					update_icon()
+					update_appearance()
 				return
 	. = ..()
 
@@ -155,14 +155,14 @@
 			if(tool.use_tool(src, user, 30, volume=100))
 				to_chat(user, "<span class='notice'>You remove [src]'s front panel.</span>")
 				deconstruction_state = NUKESTATE_PANEL_REMOVED
-				update_icon()
+				update_appearance()
 			return TRUE
 		if(NUKESTATE_WELDED)
 			to_chat(user, "<span class='notice'>You start prying off [src]'s inner plate...</span>")
 			if(tool.use_tool(src, user, 30, volume=100))
 				to_chat(user, "<span class='notice'>You pry off [src]'s inner plate. You can see the core's green glow!</span>")
 				deconstruction_state = NUKESTATE_CORE_EXPOSED
-				update_icon()
+				update_appearance()
 				START_PROCESSING(SSobj, core)
 			return TRUE
 
@@ -179,7 +179,7 @@
 /obj/machinery/nuclearbomb/update_icon_state()
 	if(deconstruction_state != NUKESTATE_INTACT)
 		icon_state = "nuclearbomb_base"
-		return
+		return ..()
 	switch(get_nuke_state())
 		if(NUKE_OFF_LOCKED, NUKE_OFF_UNLOCKED)
 			icon_state = "nuclearbomb_base"
@@ -187,6 +187,7 @@
 			icon_state = "nuclearbomb_timing"
 		if(NUKE_ON_EXPLODING)
 			icon_state = "nuclearbomb_exploding"
+	return ..()
 
 /obj/machinery/nuclearbomb/update_overlays()
 	. += ..()
@@ -406,7 +407,7 @@
 		timing = FALSE
 		detonation_timer = null
 		countdown.stop()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/nuclearbomb/proc/set_active()
 	var/turf/our_turf = get_turf(src)
@@ -432,7 +433,7 @@
 			S.switch_mode_to(initial(S.mode))
 			S.alert = FALSE
 		countdown.stop()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/nuclearbomb/proc/get_time_left()
 	if(timing)
@@ -459,7 +460,7 @@
 	exploding = TRUE
 	yes_code = FALSE
 	safety = TRUE
-	update_icon()
+	update_appearance()
 	sound_to_playing_players('sound/machines/alarm.ogg')
 	if(SSticker?.mode)
 		SSticker.roundend_check_paused = TRUE
@@ -555,7 +556,7 @@
 		S.switch_mode_to(initial(S.mode))
 		S.alert = FALSE
 	countdown.stop()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/nuclearbomb/beer/proc/local_foam()
 	var/datum/reagents/R = new/datum/reagents(1000)

code/modules/antagonists/revolution/revolution.dm

@@ -146,7 +146,7 @@
 		to_chat(admin, "<span class='danger'>Repairing flash failed!</span>")
 	else
 		flash.burnt_out = FALSE
-		flash.update_icon()
+		flash.update_appearance()
 
 /datum/antagonist/rev/head/proc/admin_demote(datum/mind/target,mob/user)
 	message_admins("[key_name_admin(user)] has demoted [key_name_admin(owner)] from head revolutionary.")

code/modules/antagonists/traitor/equipment/Malf_Modules.dm

@@ -678,7 +678,7 @@ GLOBAL_LIST_INIT(malf_modules, subtypesof(/datum/ai_module))
 		if(!is_station_level(F.z))
 			continue
 		F.obj_flags |= EMAGGED
-		F.update_icon()
+		F.update_appearance()
 	to_chat(owner, "<span class='notice'>All thermal sensors on the station have been disabled. Fire alerts will no longer be recognized.</span>")
 	owner.playsound_local(owner, 'sound/machines/terminal_off.ogg', 50, 0)
 

code/modules/aquarium/aquarium.dm

@@ -42,7 +42,7 @@
 
 /obj/structure/aquarium/Initialize()
 	. = ..()
-	update_icon()
+	update_appearance()
 	RegisterSignal(src,COMSIG_PARENT_ATTACKBY, .proc/feed_feedback)
 
 
@@ -96,7 +96,7 @@
 	if(!user.canUseTopic(src, BE_CLOSE))
 		return ..()
 	panel_open = !panel_open
-	update_icon()
+	update_appearance()
 
 /obj/structure/aquarium/wrench_act(mob/living/user, obj/item/I)
 	if(default_unfasten_wrench(user,I))
@@ -114,7 +114,7 @@
 				glass.use(2)
 				broken = FALSE
 				obj_integrity = max_integrity
-				update_icon()
+				update_appearance()
 			return TRUE
 	else
 		// This signal exists so we common items instead of adding component on init can just register creation of one in response.
@@ -123,7 +123,7 @@
 		var/datum/component/aquarium_content/content_component = I.GetComponent(/datum/component/aquarium_content)
 		if(content_component && content_component.is_ready_to_insert(src))
 			if(user.transferItemToLoc(I,src))
-				update_icon()
+				update_appearance()
 				return TRUE
 		else
 			return ..()
@@ -163,7 +163,7 @@
 				return
 			user.visible_message("<span class='danger'>[user] stuffs [living_pulled] into [src]!</span>")
 			living_pulled.forceMove(src)
-			update_icon()
+			update_appearance()
 
 ///Apply mood bonus depending on aquarium status
 /obj/structure/aquarium/proc/admire(mob/user)
@@ -250,7 +250,7 @@
 		var/datum/reagents/reagent_splash = new()
 		reagent_splash.add_reagent(/datum/reagent/water, 30)
 		chem_splash(droploc, 3, list(reagent_splash))
-	update_icon()
+	update_appearance()
 
 #undef AQUARIUM_LAYER_STEP
 #undef AQUARIUM_MIN_OFFSET

code/modules/assembly/assembly.dm

@@ -18,8 +18,12 @@
 	throw_range = 7
 	drop_sound = 'sound/items/handling/component_drop.ogg'
 	pickup_sound =  'sound/items/handling/component_pickup.ogg'
-	var/is_position_sensitive = FALSE //set to true if the device has different icons for each position.
-										//This will prevent things such as visible lasers from facing the incorrect direction when transformed by assembly_holder's update_icon()
+
+	/**
+	 * Set to true if the device has different icons for each position.
+	 * This will prevent things such as visible lasers from facing the incorrect direction when transformed by assembly_holder's update_appearance()
+	 */
+	var/is_position_sensitive = FALSE
 	var/secured = TRUE
 	var/list/attached_overlays = null
 	var/obj/item/assembly_holder/holder = null
@@ -82,7 +86,7 @@
 
 /obj/item/assembly/proc/toggle_secure()
 	secured = !secured
-	update_icon()
+	update_appearance()
 	return secured
 
 /obj/item/assembly/attackby(obj/item/W, mob/user, params)

code/modules/assembly/bomb.dm

@@ -19,10 +19,13 @@
 /obj/item/onetankbomb/examine(mob/user)
 	return bombtank.examine(user)
 
+/obj/item/onetankbomb/update_icon(updates)
+	icon = bombtank?.icon || initial(icon)
+	return ..()
+
 /obj/item/onetankbomb/update_icon_state()
-	if(bombtank)
-		icon = bombtank.icon
-		icon_state = bombtank.icon_state
+	icon_state = bombtank?.icon_state || initial(icon_state)
+	return ..()
 
 /obj/item/onetankbomb/update_overlays()
 	. = ..()
@@ -135,7 +138,7 @@
 	master = bomb
 
 	forceMove(bomb)
-	bomb.update_icon()
+	bomb.update_appearance()
 
 	user.put_in_hands(bomb) //Equips the bomb if possible, or puts it on the floor.
 	to_chat(user, "<span class='notice'>You attach [assembly] to [src].</span>")

code/modules/assembly/doorcontrol.dm

@@ -83,7 +83,7 @@
 			if(specialfunctions & BOLTS)
 				if(!D.wires.is_cut(WIRE_BOLTS) && D.hasPower())
 					D.locked = !D.locked
-					D.update_icon()
+					D.update_appearance()
 			if(specialfunctions & SHOCK)
 				if(D.secondsElectrified)
 					D.set_electrified(MACHINE_ELECTRIFIED_PERMANENT, usr)

code/modules/assembly/flash.dm

@@ -22,6 +22,9 @@
 	light_color = COLOR_WHITE
 	light_power = FLASH_LIGHT_POWER
 	light_on = FALSE
+	/// Whether we currently have the flashing overlay.
+	var/flashing = FALSE
+	/// The overlay we use for flashing.
 	var/flashing_overlay = "flash-f"
 	var/times_used = 0 //Number of times it's been used.
 	var/burnt_out = FALSE     //Is the flash burnt out?
@@ -42,18 +45,22 @@
 	attack(user,user)
 	return FIRELOSS
 
-/obj/item/assembly/flash/update_icon(flash = FALSE)
-	cut_overlays()
-	attached_overlays = list()
-	if(burnt_out)
-		add_overlay("flashburnt")
-		attached_overlays += "flashburnt"
+/obj/item/assembly/flash/update_icon(updates=ALL, flash = FALSE)
+	flashing = flash
+	. = ..()
 	if(flash)
-		add_overlay(flashing_overlay)
-		attached_overlays += flashing_overlay
 		addtimer(CALLBACK(src, /atom/.proc/update_icon), 5)
-	if(holder)
-		holder.update_icon()
+	holder?.update_icon(updates)
+
+/obj/item/assembly/flash/update_overlays()
+	attached_overlays = list()
+	. = ..()
+	if(burnt_out)
+		. += "flashburnt"
+		attached_overlays += "flashburnt"
+	if(flashing)
+		. += flashing_overlay
+		attached_overlays += flashing_overlay
 
 /obj/item/assembly/flash/proc/clown_check(mob/living/carbon/human/user)
 	if(HAS_TRAIT(user, TRAIT_CLUMSY) && prob(50))
@@ -64,7 +71,7 @@
 /obj/item/assembly/flash/proc/burn_out() //Made so you can override it if you want to have an invincible flash from R&D or something.
 	if(!burnt_out)
 		burnt_out = TRUE
-		update_icon()
+		update_appearance()
 	if(ismob(loc))
 		var/mob/M = loc
 		M.visible_message("<span class='danger'>[src] burns out!</span>","<span class='userdanger'>[src] burns out!</span>")
@@ -113,7 +120,7 @@
 	addtimer(CALLBACK(src, .proc/flash_end), FLASH_LIGHT_DURATION, TIMER_OVERRIDE|TIMER_UNIQUE)
 	times_used++
 	flash_recharge()
-	update_icon(TRUE)
+	update_icon(ALL, TRUE)
 	if(user && !clown_check(user))
 		return FALSE
 	return TRUE
@@ -239,7 +246,7 @@
 	if(issilicon(M))
 		var/mob/living/silicon/robot/flashed_borgo = M
 		log_combat(user, flashed_borgo, "flashed", src)
-		update_icon(TRUE)
+		update_icon(ALL, TRUE)
 		if(!flashed_borgo.flash_act(affect_silicon = TRUE))
 			user.visible_message("<span class='warning'>[user] fails to blind [flashed_borgo] with the flash!</span>", "<span class='warning'>You fail to blind [flashed_borgo] with the flash!</span>")
 			return
@@ -346,7 +353,7 @@
 	overheat = TRUE
 	addtimer(CALLBACK(src, .proc/cooldown), flashcd)
 	playsound(src, 'sound/weapons/flash.ogg', 100, TRUE)
-	update_icon(1)
+	update_icon(ALL, TRUE)
 	return TRUE
 
 

code/modules/assembly/health.dm

@@ -27,7 +27,7 @@
 	else
 		scanning = FALSE
 		STOP_PROCESSING(SSobj, src)
-	update_icon()
+	update_appearance()
 	return secured
 
 /obj/item/assembly/health/AltClick(mob/living/user)

code/modules/assembly/holder.dm

@@ -27,7 +27,7 @@
 	attach(A,user)
 	attach(A2,user)
 	name = "[A.name]-[A2.name] assembly"
-	update_icon()
+	update_appearance()
 	SSblackbox.record_feedback("tally", "assembly_made", 1, "[initial(A.name)]-[initial(A2.name)]")
 
 /obj/item/assembly_holder/proc/attach(obj/item/assembly/A, mob/user)
@@ -44,27 +44,31 @@
 		a_right = A
 	A.holder_movement()
 
-/obj/item/assembly_holder/update_icon()
-	cut_overlays()
+/obj/item/assembly_holder/update_appearance(updates=ALL)
+	. = ..()
+	master?.update_appearance(updates)
+
+/obj/item/assembly_holder/update_overlays()
+	. = ..()
 	if(a_left)
-		add_overlay("[a_left.icon_state]_left")
-		for(var/O in a_left.attached_overlays)
-			add_overlay("[O]_l")
+		. += "[a_left.icon_state]_left"
+		for(var/left_overlay in a_left.attached_overlays)
+			. += "[left_overlay]_l"
 
-	if(a_right)
-		if(a_right.is_position_sensitive)
-			add_overlay("[a_right.icon_state]_right")
-			for(var/O in a_right.attached_overlays)
-				add_overlay("[O]_r")
-		else
-			var/mutable_appearance/right = mutable_appearance(icon, "[a_right.icon_state]_left")
-			right.transform = matrix(-1, 0, 0, 0, 1, 0)
-			for(var/O in a_right.attached_overlays)
-				right.add_overlay("[O]_l")
-			add_overlay(right)
+	if(!a_right)
+		return
 
-	if(master)
-		master.update_icon()
+	if(a_right.is_position_sensitive)
+		. += "[a_right.icon_state]_right"
+		for(var/right_overlay in a_right.attached_overlays)
+			. += "[right_overlay]_r"
+		return
+
+	var/mutable_appearance/right = mutable_appearance(icon, "[a_right.icon_state]_left")
+	right.transform = matrix(-1, 0, 0, 0, 1, 0)
+	for(var/right_overlay in a_right.attached_overlays)
+		right.add_overlay("[right_overlay]_l")
+	. += right
 
 /obj/item/assembly_holder/Crossed(atom/movable/AM as mob|obj)
 	. = ..()

code/modules/assembly/infrared.dm

@@ -42,7 +42,7 @@
 		return FALSE //Cooldown check
 	on = !on
 	refreshBeam()
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/item/assembly/infra/toggle_secure()
@@ -53,22 +53,23 @@
 	else
 		QDEL_LIST(beams)
 		STOP_PROCESSING(SSobj, src)
-	update_icon()
+	update_appearance()
 	return secured
 
-/obj/item/assembly/infra/update_icon()
-	cut_overlays()
-	attached_overlays = list()
-	if(on)
-		add_overlay("infrared_on")
-		attached_overlays += "infrared_on"
-		if(visible && secured)
-			add_overlay("infrared_visible")
-			attached_overlays += "infrared_visible"
+/obj/item/assembly/infra/update_appearance(updates=ALL)
+	. = ..()
+	holder?.update_appearance(updates)
 
-	if(holder)
-		holder.update_icon()
-	return
+/obj/item/assembly/infra/update_overlays()
+	. = ..()
+	attached_overlays = list()
+	if(!on)
+		return
+	. += "infrared_on"
+	attached_overlays += "infrared_on"
+	if(visible && secured)
+		. += "infrared_visible"
+		attached_overlays += "infrared_visible"
 
 /obj/item/assembly/infra/dropped()
 	. = ..()
@@ -213,7 +214,7 @@
 			visible = !visible
 			. = TRUE
 
-	update_icon()
+	update_appearance()
 	refreshBeam()
 
 /***************************IBeam*********************************/

code/modules/assembly/mousetrap.dm

@@ -23,16 +23,16 @@
 				if((HAS_TRAIT(user, TRAIT_DUMB) || HAS_TRAIT(user, TRAIT_CLUMSY)) && prob(50))
 					to_chat(user, "<span class='warning'>Your hand slips, setting off the trigger!</span>")
 					pulse(FALSE)
-		update_icon()
+		update_appearance()
 		playsound(src, 'sound/weapons/handcuffs.ogg', 30, TRUE, -3)
 
-/obj/item/assembly/mousetrap/update_icon()
-	if(armed)
-		icon_state = "mousetraparmed"
-	else
-		icon_state = "mousetrap"
-	if(holder)
-		holder.update_icon()
+/obj/item/assembly/mousetrap/update_icon_state()
+	icon_state = "mousetrap[armed ? "armed" : ""]"
+	return ..()
+
+/obj/item/assembly/mousetrap/update_icon(updates=ALL)
+	. = ..()
+	holder?.update_icon(updates)
 
 /obj/item/assembly/mousetrap/proc/triggered(mob/target, type = "feet")
 	if(!armed)
@@ -43,7 +43,7 @@
 		if(HAS_TRAIT(H, TRAIT_PIERCEIMMUNE))
 			playsound(src, 'sound/effects/snap.ogg', 50, TRUE)
 			armed = FALSE
-			update_icon()
+			update_appearance()
 			pulse(FALSE)
 			return FALSE
 		switch(type)
@@ -71,7 +71,7 @@
 		visible_message("<span class='boldannounce'>Skreeeee!</span>") //He's simply too large to be affected by a tiny mouse trap.
 	playsound(src, 'sound/effects/snap.ogg', 50, TRUE)
 	armed = FALSE
-	update_icon()
+	update_appearance()
 	pulse(FALSE)
 
 
@@ -89,7 +89,7 @@
 			return
 		to_chat(user, "<span class='notice'>You disarm [src].</span>")
 	armed = !armed
-	update_icon()
+	update_appearance()
 	playsound(src, 'sound/weapons/handcuffs.ogg', 30, TRUE, -3)
 
 

code/modules/assembly/proximity.dm

@@ -32,7 +32,7 @@
 		timing = !timing
 	else
 		scanning = FALSE
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/item/assembly/prox_sensor/on_detach()
@@ -53,7 +53,7 @@
 	else
 		START_PROCESSING(SSobj, src)
 		proximity_monitor.SetHost(loc,src)
-	update_icon()
+	update_appearance()
 	return secured
 
 /obj/item/assembly/prox_sensor/HasProximity(atom/movable/AM as mob|obj)
@@ -87,7 +87,7 @@
 		return FALSE
 	scanning = scan
 	proximity_monitor.SetRange(scanning ? sensitivity : 0)
-	update_icon()
+	update_appearance()
 
 /obj/item/assembly/prox_sensor/proc/sensitivity_change(value)
 	var/sense = min(max(sensitivity + value, 0), 5)
@@ -95,18 +95,19 @@
 	if(scanning && proximity_monitor.SetRange(sense))
 		sense()
 
-/obj/item/assembly/prox_sensor/update_icon()
-	cut_overlays()
+/obj/item/assembly/prox_sensor/update_appearance()
+	. = ..()
+	holder?.update_appearance()
+
+/obj/item/assembly/prox_sensor/update_overlays()
+	. = ..()
 	attached_overlays = list()
 	if(timing)
-		add_overlay("prox_timing")
+		. += "prox_timing"
 		attached_overlays += "prox_timing"
 	if(scanning)
-		add_overlay("prox_scanning")
+		. += "prox_scanning"
 		attached_overlays += "prox_scanning"
-	if(holder)
-		holder.update_icon()
-	return
 
 /obj/item/assembly/prox_sensor/ui_status(mob/user)
 	if(is_secured(user))
@@ -144,7 +145,7 @@
 				. = TRUE
 		if("time")
 			timing = !timing
-			update_icon()
+			update_appearance()
 			. = TRUE
 		if("input")
 			var/value = text2num(params["adjust"])

code/modules/assembly/signaler.dm

@@ -61,10 +61,9 @@
 	signal()
 	return TRUE
 
-/obj/item/assembly/signaler/update_icon()
-	if(holder)
-		holder.update_icon()
-	return
+/obj/item/assembly/signaler/update_appearance()
+	. = ..()
+	holder?.update_appearance()
 
 /obj/item/assembly/signaler/ui_status(mob/user)
 	if(is_secured(user))
@@ -110,7 +109,7 @@
 				code = initial(code)
 			. = TRUE
 
-	update_icon()
+	update_appearance()
 
 /obj/item/assembly/signaler/attackby(obj/item/W, mob/user, params)
 	if(issignaler(W))

code/modules/assembly/timer.dm

@@ -40,7 +40,7 @@
 	if(!..())
 		return FALSE//Cooldown check
 	timing = !timing
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/item/assembly/timer/toggle_secure()
@@ -50,7 +50,7 @@
 	else
 		timing = FALSE
 		STOP_PROCESSING(SSobj, src)
-	update_icon()
+	update_appearance()
 	return secured
 
 /obj/item/assembly/timer/proc/timer_end()
@@ -64,7 +64,7 @@
 			LM.playsound_local(get_turf(src), 'sound/machines/triple_beep.ogg', ASSEMBLY_BEEP_VOLUME, TRUE)
 	if(loop)
 		timing = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/item/assembly/timer/process(delta_time)
 	if(!timing)
@@ -75,14 +75,16 @@
 		timer_end()
 		time = saved_time
 
-/obj/item/assembly/timer/update_icon()
-	cut_overlays()
+/obj/item/assembly/timer/update_appearance()
+	. = ..()
+	holder?.update_appearance()
+
+/obj/item/assembly/timer/update_overlays()
+	. = ..()
 	attached_overlays = list()
 	if(timing)
-		add_overlay("timer_timing")
+		. += "timer_timing"
 		attached_overlays += "timer_timing"
-	if(holder)
-		holder.update_icon()
 
 /obj/item/assembly/timer/ui_status(mob/user)
 	if(is_secured(user))
@@ -113,7 +115,7 @@
 			timing = !timing
 			if(timing && istype(holder, /obj/item/transfer_valve))
 				log_bomber(usr, "activated a", src, "attachment on [holder]")
-			update_icon()
+			update_appearance()
 			. = TRUE
 		if("repeat")
 			loop = !loop

code/modules/atmospherics/machinery/airalarm.dm

@@ -227,7 +227,7 @@
 	if(name == initial(name))
 		name = "[get_area_name(src)] Air Alarm"
 
-	update_icon()
+	update_appearance()
 
 /obj/machinery/airalarm/Destroy()
 	SSradio.remove_object(src, frequency)
@@ -451,7 +451,7 @@
 			if(A.atmosalert(FALSE, src))
 				post_alert(0)
 			. = TRUE
-	update_icon()
+	update_appearance()
 
 
 /obj/machinery/airalarm/proc/reset(wire)
@@ -459,7 +459,7 @@
 		if(WIRE_POWER)
 			if(!wires.is_cut(WIRE_POWER))
 				shorted = FALSE
-				update_icon()
+				update_appearance()
 		if(WIRE_AI)
 			if(!wires.is_cut(WIRE_AI))
 				aidisabled = FALSE
@@ -648,11 +648,11 @@
 				icon_state = "alarm_b2"
 			if(0)
 				icon_state = "alarm_b1"
-		return
+		return ..()
 
 	if((machine_stat & (NOPOWER|BROKEN)) || shorted)
 		icon_state = "alarmp"
-		return
+		return ..()
 
 	var/area/A = get_area(src)
 	switch(max(danger_level, A.atmosalm))
@@ -662,6 +662,7 @@
 			icon_state = "alarm2" //yes, alarm2 is yellow alarm
 		if(2)
 			icon_state = "alarm1"
+	return ..()
 
 /obj/machinery/airalarm/process()
 	if((machine_stat & (NOPOWER|BROKEN)) || shorted)
@@ -732,7 +733,7 @@
 	if(A.atmosalert(new_area_danger_level,src)) //if area was in normal state or if area was in alert state
 		post_alert(new_area_danger_level)
 
-	update_icon()
+	update_appearance()
 
 /obj/machinery/airalarm/attackby(obj/item/W, mob/user, params)
 	switch(buildstage)
@@ -742,13 +743,13 @@
 				to_chat(user, "<span class='notice'>You cut the final wires.</span>")
 				new /obj/item/stack/cable_coil(loc, 5)
 				buildstage = 1
-				update_icon()
+				update_appearance()
 				return
 			else if(W.tool_behaviour == TOOL_SCREWDRIVER)  // Opening that Air Alarm up.
 				W.play_tool_sound(src)
 				panel_open = !panel_open
 				to_chat(user, "<span class='notice'>The wires have been [panel_open ? "exposed" : "unexposed"].</span>")
-				update_icon()
+				update_appearance()
 				return
 			else if(W.GetID())// trying to unlock the interface with an ID card
 				togglelock(user)
@@ -767,7 +768,7 @@
 						new /obj/item/electronics/airalarm( src.loc )
 						playsound(src.loc, 'sound/items/deconstruct.ogg', 50, TRUE)
 						buildstage = 0
-						update_icon()
+						update_appearance()
 				return
 
 			if(istype(W, /obj/item/stack/cable_coil))
@@ -788,14 +789,14 @@
 						shorted = 0
 						post_alert(0)
 						buildstage = 2
-						update_icon()
+						update_appearance()
 				return
 		if(0)
 			if(istype(W, /obj/item/electronics/airalarm))
 				if(user.temporarilyRemoveItemFromInventory(W))
 					to_chat(user, "<span class='notice'>You insert the circuit.</span>")
 					buildstage = 1
-					update_icon()
+					update_appearance()
 					qdel(W)
 				return
 
@@ -806,7 +807,7 @@
 				user.visible_message("<span class='notice'>[user] fabricates a circuit and places it into [src].</span>", \
 				"<span class='notice'>You adapt an air alarm circuit and slot it into the assembly.</span>")
 				buildstage = 1
-				update_icon()
+				update_appearance()
 				return
 
 			if(W.tool_behaviour == TOOL_WRENCH)
@@ -829,7 +830,7 @@
 			user.visible_message("<span class='notice'>[user] fabricates a circuit and places it into [src].</span>", \
 			"<span class='notice'>You adapt an air alarm circuit and slot it into the assembly.</span>")
 			buildstage = 1
-			update_icon()
+			update_appearance()
 			return TRUE
 	return FALSE
 

code/modules/atmospherics/machinery/atmosmachinery.dm

@@ -158,7 +158,7 @@
 			if(can_be_node(target, i))
 				nodes[i] = target
 				break
-	update_icon()
+	update_appearance()
 
 /**
  * setter for pipe layers
@@ -169,7 +169,7 @@
  */
 /obj/machinery/atmospherics/proc/setPipingLayer(new_layer)
 	piping_layer = (pipe_flags & PIPING_DEFAULT_LAYER_ONLY) ? PIPING_LAYER_DEFAULT : new_layer
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/update_icon()
 	layer = initial(layer) + piping_layer / 1000
@@ -280,7 +280,7 @@
 		var/obj/machinery/atmospherics/pipe/P = reference
 		P.destroy_network()
 	nodes[nodes.Find(reference)] = null
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/pipe)) //lets you autodrop

code/modules/atmospherics/machinery/components/binary_devices/circulator.dm

@@ -67,18 +67,21 @@
 
 /obj/machinery/atmospherics/components/binary/circulator/process_atmos()
 	..()
-	update_icon()
+	update_appearance()
 
-/obj/machinery/atmospherics/components/binary/circulator/update_icon()
+/obj/machinery/atmospherics/components/binary/circulator/update_icon_state()
 	if(!is_operational)
 		icon_state = "circ-p-[flipped]"
-	else if(last_pressure_delta > 0)
+		return ..()
+	if(last_pressure_delta > 0)
 		if(last_pressure_delta > ONE_ATMOSPHERE)
 			icon_state = "circ-run-[flipped]"
 		else
 			icon_state = "circ-slow-[flipped]"
-	else
-		icon_state = "circ-off-[flipped]"
+		return ..()
+
+	icon_state = "circ-off-[flipped]"
+	return ..()
 
 /obj/machinery/atmospherics/components/binary/circulator/wrench_act(mob/living/user, obj/item/I)
 	if(!panel_open)
@@ -162,7 +165,7 @@
 		generator.cold_circ = null
 	else
 		generator.hot_circ = null
-	generator.update_icon()
+	generator.update_appearance()
 	generator = null
 
 /obj/machinery/atmospherics/components/binary/circulator/setPipingLayer(new_layer)
@@ -184,4 +187,4 @@
 
 	flipped = !flipped
 	to_chat(usr, "<span class='notice'>You flip [src].</span>")
-	update_icon()
+	update_appearance()

code/modules/atmospherics/machinery/components/binary_devices/dp_vent_pump.dm

@@ -170,8 +170,8 @@
 
 	addtimer(CALLBACK(src, .proc/broadcast_status), 2)
 
-	if(!("status" in signal.data)) //do not update_icon
-		update_icon()
+	if(!("status" in signal.data)) //do not update_appearance
+		update_appearance()
 
 /obj/machinery/atmospherics/components/binary/dp_vent_pump/high_volume
 	name = "large dual-port air vent"

code/modules/atmospherics/machinery/components/binary_devices/passive_gate.dm

@@ -31,7 +31,7 @@ Passive gate is similar to the regular pump except:
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/passive_gate/AltClick(mob/user)
@@ -39,7 +39,7 @@ Passive gate is similar to the regular pump except:
 		target_pressure = MAX_OUTPUT_PRESSURE
 		investigate_log("was set to [target_pressure] kPa by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the pressure output on [src] to [target_pressure] kPa.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/passive_gate/Destroy()
@@ -117,7 +117,7 @@ Passive gate is similar to the regular pump except:
 			if(.)
 				target_pressure = clamp(pressure, 0, ONE_ATMOSPHERE*100)
 				investigate_log("was set to [target_pressure] kPa by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/passive_gate/atmosinit()
 	..()
@@ -147,7 +147,7 @@ Passive gate is similar to the regular pump except:
 		return
 
 	broadcast_status()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/passive_gate/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/binary_devices/pressure_valve.dm

@@ -24,7 +24,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/pressure_valve/AltClick(mob/user)
@@ -32,7 +32,7 @@
 		target_pressure = MAX_OUTPUT_PRESSURE
 		investigate_log("was set to [target_pressure] kPa by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You set the target pressure on [src] to [target_pressure] kPa.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/pressure_valve/Destroy()
@@ -117,7 +117,7 @@
 			if(.)
 				target_pressure = clamp(pressure, 0, ONE_ATMOSPHERE*100)
 				investigate_log("was set to [target_pressure] kPa by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/pressure_valve/atmosinit()
 	. = ..()
@@ -147,7 +147,7 @@
 		return
 
 	broadcast_status()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/pressure_valve/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/binary_devices/pump.dm

@@ -31,7 +31,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/pump/AltClick(mob/user)
@@ -39,7 +39,7 @@
 		target_pressure = MAX_OUTPUT_PRESSURE
 		investigate_log("was set to [target_pressure] kPa by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the pressure output on [src] to [target_pressure] kPa.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/pump/Destroy()
@@ -115,7 +115,7 @@
 			if(.)
 				target_pressure = clamp(pressure, 0, MAX_OUTPUT_PRESSURE)
 				investigate_log("was set to [target_pressure] kPa by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/pump/atmosinit()
 	..()
@@ -145,7 +145,7 @@
 		return
 
 	broadcast_status()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/pump/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/binary_devices/temperature_gate.dm

@@ -23,7 +23,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/temperature_gate/AltClick(mob/user)
@@ -31,7 +31,7 @@
 		target_temperature = max_temperature
 		investigate_log("was set to [target_temperature] K by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You set the target temperature on [src] to [target_temperature] K.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 
@@ -110,7 +110,7 @@
 			if(.)
 				target_temperature = clamp(minimum_temperature, temperature, max_temperature)
 				investigate_log("was set to [target_temperature] K by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/temperature_gate/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/binary_devices/temperature_pump.dm

@@ -18,14 +18,14 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/temperature_pump/AltClick(mob/user)
 	if(can_interact(user) && !(heat_transfer_rate == max_heat_transfer_rate))
 		heat_transfer_rate = max_heat_transfer_rate
 		investigate_log("was set to [heat_transfer_rate]% by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/temperature_pump/update_icon_nopipes()
@@ -92,4 +92,4 @@
 			if(.)
 				heat_transfer_rate = clamp(rate, 0, max_heat_transfer_rate)
 				investigate_log("was set to [heat_transfer_rate]% by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()

code/modules/atmospherics/machinery/components/binary_devices/volume_pump.dm

@@ -32,7 +32,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/volume_pump/AltClick(mob/user)
@@ -40,7 +40,7 @@
 		transfer_rate = MAX_TRANSFER_RATE
 		investigate_log("was set to [transfer_rate] L/s by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the volume output on [src] to [transfer_rate] L/s.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/binary/volume_pump/Destroy()
@@ -147,7 +147,7 @@
 			if(.)
 				transfer_rate = clamp(rate, 0, MAX_TRANSFER_RATE)
 				investigate_log("was set to [transfer_rate] L/s by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/volume_pump/receive_signal(datum/signal/signal)
 	if(!signal.data["tag"] || (signal.data["tag"] != id) || (signal.data["sigtype"]!="command"))
@@ -170,10 +170,10 @@
 
 	if("status" in signal.data)
 		broadcast_status()
-		return //do not update_icon
+		return //do not update_appearance
 
 	broadcast_status()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/binary/volume_pump/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/components_base.dm

@@ -35,7 +35,7 @@
 
 /obj/machinery/atmospherics/components/proc/hide_pipe(datum/source, covered)
 	showpipe = !covered
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/update_icon()
 	update_icon_nopipes()

code/modules/atmospherics/machinery/components/fusion/hypertorus.dm

@@ -108,14 +108,15 @@
 			node.addMember(src)
 		SSair.add_to_rebuild_queue(src)
 
-/obj/machinery/atmospherics/components/unary/hypertorus/update_icon()
-	. = ..()
+/obj/machinery/atmospherics/components/unary/hypertorus/update_icon_state()
 	if(panel_open)
 		icon_state = icon_state_open
-	else if(active)
+		return ..()
+	if(active)
 		icon_state = icon_state_active
-	else
-		icon_state = icon_state_off
+		return ..()
+	icon_state = icon_state_off
+	return ..()
 
 /obj/machinery/atmospherics/components/unary/hypertorus/fuel_input
 	name = "HFR fuel input port"
@@ -411,22 +412,22 @@
 		return
 	to_chat(user, "<span class='notice'>You link all parts toghether.</span>")
 	active = TRUE
-	update_icon()
+	update_appearance()
 	linked_interface.active = TRUE
-	linked_interface.update_icon()
+	linked_interface.update_appearance()
 	RegisterSignal(linked_interface, COMSIG_PARENT_QDELETING, .proc/unregister_signals)
 	linked_input.active = TRUE
-	linked_input.update_icon()
+	linked_input.update_appearance()
 	RegisterSignal(linked_input, COMSIG_PARENT_QDELETING, .proc/unregister_signals)
 	linked_output.active = TRUE
-	linked_output.update_icon()
+	linked_output.update_appearance()
 	RegisterSignal(linked_output, COMSIG_PARENT_QDELETING, .proc/unregister_signals)
 	linked_moderator.active = TRUE
-	linked_moderator.update_icon()
+	linked_moderator.update_appearance()
 	RegisterSignal(linked_moderator, COMSIG_PARENT_QDELETING, .proc/unregister_signals)
 	for(var/obj/machinery/hypertorus/corner/corner in corners)
 		corner.active = TRUE
-		corner.update_icon()
+		corner.update_appearance()
 		RegisterSignal(corner, COMSIG_PARENT_QDELETING, .proc/unregister_signals)
 	soundloop = new(list(src), TRUE)
 	soundloop.volume = 5
@@ -445,27 +446,27 @@
 	if(!active)
 		return
 	active = FALSE
-	update_icon()
+	update_appearance()
 	if(linked_interface)
 		linked_interface.active = FALSE
-		linked_interface.update_icon()
+		linked_interface.update_appearance()
 		linked_interface = null
 	if(linked_input)
 		linked_input.active = FALSE
-		linked_input.update_icon()
+		linked_input.update_appearance()
 		linked_input = null
 	if(linked_output)
 		linked_output.active = FALSE
-		linked_output.update_icon()
+		linked_output.update_appearance()
 		linked_output = null
 	if(linked_moderator)
 		linked_moderator.active = FALSE
-		linked_moderator.update_icon()
+		linked_moderator.update_appearance()
 		linked_moderator = null
 	if(corners.len)
 		for(var/obj/machinery/hypertorus/corner/corner in corners)
 			corner.active = FALSE
-			corner.update_icon()
+			corner.update_appearance()
 		corners = list()
 	QDEL_NULL(soundloop)
 
@@ -1154,13 +1155,15 @@
 		return
 	return ..()
 
-/obj/machinery/hypertorus/update_icon()
+/obj/machinery/hypertorus/update_icon_state()
 	if(panel_open)
 		icon_state = icon_state_open
-	else if(active)
+		return ..()
+	if(active)
 		icon_state = icon_state_active
-	else
-		icon_state = icon_state_off
+		return ..()
+	icon_state = icon_state_off
+	return ..()
 
 /obj/machinery/hypertorus/interface
 	name = "HFR interface"

code/modules/atmospherics/machinery/components/trinary_devices/filter.dm

@@ -18,7 +18,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/trinary/filter/AltClick(mob/user)
@@ -26,7 +26,7 @@
 		transfer_rate = MAX_TRANSFER_RATE
 		investigate_log("was set to [transfer_rate] L/s by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the volume output on [src] to [transfer_rate] L/s.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/trinary/filter/proc/set_frequency(new_frequency)
@@ -39,22 +39,14 @@
 	SSradio.remove_object(src,frequency)
 	return ..()
 
-/obj/machinery/atmospherics/components/trinary/filter/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/components/trinary/filter/update_overlays()
+	. = ..()
 	for(var/direction in GLOB.cardinals)
 		if(!(direction & initialize_directions))
 			continue
+
 		var/obj/machinery/atmospherics/node = findConnecting(direction)
-
-		var/image/cap
-		if(node)
-			cap = getpipeimage(icon, "cap", direction, node.pipe_color, piping_layer = piping_layer, trinary = TRUE)
-		else
-			cap = getpipeimage(icon, "cap", direction, piping_layer = piping_layer, trinary = TRUE)
-
-		add_overlay(cap)
-
-	return ..()
+		. += getpipeimage(icon, "cap", direction, node?.pipe_color, piping_layer, TRUE)
 
 /obj/machinery/atmospherics/components/trinary/filter/update_icon_nopipes()
 	var/on_state = on && nodes[1] && nodes[2] && nodes[3] && is_operational
@@ -168,7 +160,7 @@
 				filter_name = GLOB.meta_gas_info[gas][META_GAS_NAME]
 			investigate_log("was set to filter [filter_name] by [key_name(usr)]", INVESTIGATE_ATMOS)
 			. = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/trinary/filter/can_unwrench(mob/user)
 	. = ..()

code/modules/atmospherics/machinery/components/trinary_devices/mixer.dm

@@ -20,7 +20,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/trinary/mixer/AltClick(mob/user)
@@ -28,25 +28,17 @@
 		target_pressure = MAX_OUTPUT_PRESSURE
 		investigate_log("was set to [target_pressure] kPa by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the pressure output on [src] to [target_pressure] kPa.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
-/obj/machinery/atmospherics/components/trinary/mixer/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/components/trinary/mixer/update_overlays()
+	. = ..()
 	for(var/direction in GLOB.cardinals)
 		if(!(direction & initialize_directions))
 			continue
+
 		var/obj/machinery/atmospherics/node = findConnecting(direction)
-
-		var/image/cap
-		if(node)
-			cap = getpipeimage(icon, "cap", direction, node.pipe_color, piping_layer = piping_layer, trinary = TRUE)
-		else
-			cap = getpipeimage(icon, "cap", direction, piping_layer = piping_layer, trinary = TRUE)
-
-		add_overlay(cap)
-
-	return ..()
+		. += getpipeimage(icon, "cap", direction, node?.pipe_color, piping_layer, TRUE)
 
 /obj/machinery/atmospherics/components/trinary/mixer/update_icon_nopipes()
 	var/on_state = on && nodes[1] && nodes[2] && nodes[3] && is_operational
@@ -170,7 +162,7 @@
 			adjust_node1_value(100 - value)
 			investigate_log("was set to [node2_concentration] % on node 2 by [key_name(usr)]", INVESTIGATE_ATMOS)
 			. = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/trinary/mixer/proc/adjust_node1_value(newValue)
 	node1_concentration = newValue / 100

code/modules/atmospherics/machinery/components/unary_devices/cryo.dm

@@ -122,7 +122,7 @@
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/set_occupant(atom/movable/new_occupant)
 	. = ..()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/on_construction()
 	..(dir, dir)
@@ -183,10 +183,13 @@
 		beaker.forceMove(drop_location())
 		beaker = null
 
+/obj/machinery/atmospherics/components/unary/cryo_cell/update_icon_state()
+	icon_state = (state_open) ? "pod-open" : ((on && is_operational) ? "pod-on" : "pod-off")
+	return ..()
+
 /obj/machinery/atmospherics/components/unary/cryo_cell/update_icon()
 	. = ..()
 	plane = initial(plane)
-	icon_state = (state_open) ? "pod-open" : (on && is_operational) ? "pod-on" : "pod-off"
 
 GLOBAL_VAR_INIT(cryo_overlay_cover_on, mutable_appearance('icons/obj/cryogenics.dmi', "cover-on", layer = ABOVE_WINDOW_LAYER + 0.02))
 GLOBAL_VAR_INIT(cryo_overlay_cover_off, mutable_appearance('icons/obj/cryogenics.dmi', "cover-off", layer = ABOVE_WINDOW_LAYER + 0.02))
@@ -197,10 +200,7 @@ GLOBAL_VAR_INIT(cryo_overlay_cover_off, mutable_appearance('icons/obj/cryogenics
 		. += "pod-panel"
 	if(state_open)
 		return
-	if(on && is_operational)
-		. += GLOB.cryo_overlay_cover_on
-	else
-		. += GLOB.cryo_overlay_cover_off
+	. += (on && is_operational) ? GLOB.cryo_overlay_cover_on : GLOB.cryo_overlay_cover_off
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/nap_violation(mob/violator)
 	open_machine()
@@ -212,7 +212,7 @@ GLOBAL_VAR_INIT(cryo_overlay_cover_off, mutable_appearance('icons/obj/cryogenics
 	SEND_SIGNAL(src, COMSIG_CRYO_SET_ON, new_value)
 	. = on
 	on = new_value
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/on_set_is_operational(old_value)
 	if(old_value) //Turned off
@@ -315,7 +315,7 @@ GLOBAL_VAR_INIT(cryo_overlay_cover_off, mutable_appearance('icons/obj/cryogenics
 
 		if(air1.temperature > 2000)
 			take_damage(clamp((air1.temperature)/200, 10, 20), BURN)
-		
+
 		update_parents()
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/relaymove(mob/living/user, direction)
@@ -392,7 +392,7 @@ GLOBAL_VAR_INIT(cryo_overlay_cover_off, mutable_appearance('icons/obj/cryogenics
 		|| default_change_direction_wrench(user, I) \
 		|| default_pry_open(I) \
 		|| default_deconstruction_crowbar(I))
-		update_icon()
+		update_appearance()
 		return
 	else if(I.tool_behaviour == TOOL_SCREWDRIVER)
 		to_chat(user, "<span class='warning'>You can't access the maintenance panel while the pod is " \

code/modules/atmospherics/machinery/components/unary_devices/heat_exchanger.dm

@@ -23,13 +23,15 @@
 	piping_layer = 4
 	icon_state = "he_map-4"
 
+/obj/machinery/atmospherics/components/unary/heat_exchanger/update_icon_state()
+	icon_state = "he[nodes[1] ? 1 : 0]"
+	return ..()
+
 /obj/machinery/atmospherics/components/unary/heat_exchanger/update_icon()
+	. = ..()
 	if(nodes[1])
-		icon_state = "he1"
 		var/obj/machinery/atmospherics/node = nodes[1]
 		add_atom_colour(node.color, FIXED_COLOUR_PRIORITY)
-	else
-		icon_state = "he0"
 	PIPING_LAYER_SHIFT(src, piping_layer)
 
 /obj/machinery/atmospherics/components/unary/heat_exchanger/atmosinit()

code/modules/atmospherics/machinery/components/unary_devices/outlet_injector.dm

@@ -27,7 +27,7 @@
 	if(can_interact(user))
 		on = !on
 		investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/unary/outlet_injector/AltClick(mob/user)
@@ -35,7 +35,7 @@
 		volume_rate = MAX_TRANSFER_RATE
 		investigate_log("was set to [volume_rate] L/s by [key_name(user)]", INVESTIGATE_ATMOS)
 		to_chat(user, "<span class='notice'>You maximize the volume output on [src] to [volume_rate] L/s.</span>")
-		update_icon()
+		update_appearance()
 	return ..()
 
 /obj/machinery/atmospherics/components/unary/outlet_injector/Destroy()
@@ -139,7 +139,7 @@
 	addtimer(CALLBACK(src, .proc/broadcast_status), 2)
 
 	if(!("status" in signal.data)) //do not update_icon
-		update_icon()
+		update_appearance()
 
 
 /obj/machinery/atmospherics/components/unary/outlet_injector/ui_interact(mob/user, datum/tgui/ui)
@@ -176,7 +176,7 @@
 			if(.)
 				volume_rate = clamp(rate, 0, MAX_TRANSFER_RATE)
 				investigate_log("was set to [volume_rate] L/s by [key_name(usr)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 	broadcast_status()
 
 /obj/machinery/atmospherics/components/unary/outlet_injector/can_unwrench(mob/user)

code/modules/atmospherics/machinery/components/unary_devices/thermomachine.dm

@@ -31,7 +31,7 @@
 	. = ..()
 	initialize_directions = dir
 	RefreshParts()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/thermomachine/proc/swap_function()
 	cooling = !cooling
@@ -45,7 +45,7 @@
 		icon_state_open = "heater-o"
 	target_temperature = T20C
 	RefreshParts()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/thermomachine/on_construction(obj_color, set_layer)
 	var/obj/item/circuitboard/machine/thermomachine/board = circuit
@@ -72,17 +72,19 @@
 			calculated_laser_rating += laser.rating
 		max_temperature = T20C + (base_heating * calculated_laser_rating) //573.15K with T1 stock parts
 
-/obj/machinery/atmospherics/components/unary/thermomachine/update_icon()
-	cut_overlays()
-
+/obj/machinery/atmospherics/components/unary/thermomachine/update_icon_state()
 	if(panel_open)
 		icon_state = icon_state_open
-	else if(on && is_operational)
+		return ..()
+	if(on && is_operational)
 		icon_state = icon_state_on
-	else
-		icon_state = icon_state_off
+		return ..()
+	icon_state = icon_state_off
+	return ..()
 
-	add_overlay(getpipeimage(icon, "pipe", dir, , piping_layer))
+/obj/machinery/atmospherics/components/unary/thermomachine/update_overlays()
+	. = ..()
+	. += getpipeimage(icon, "pipe", dir, , piping_layer)
 
 /obj/machinery/atmospherics/components/unary/thermomachine/update_icon_nopipes()
 	cut_overlays()
@@ -221,14 +223,14 @@
 				target_temperature = clamp(target, min_temperature, max_temperature)
 				investigate_log("was set to [target_temperature] K by [key_name(usr)]", INVESTIGATE_ATMOS)
 
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/thermomachine/CtrlClick(mob/living/user)
 	if(!can_interact(user))
 		return
 	on = !on
 	investigate_log("was turned [on ? "on" : "off"] by [key_name(user)]", INVESTIGATE_ATMOS)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/thermomachine/freezer
 	icon_state = "freezer"

code/modules/atmospherics/machinery/components/unary_devices/unary_devices.dm

@@ -13,7 +13,7 @@
 
 /obj/machinery/atmospherics/components/unary/on_construction()
 	..()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/proc/assign_uid_vents()
 	uid = num2text(gl_uid++)

code/modules/atmospherics/machinery/components/unary_devices/vent_pump.dm

@@ -246,11 +246,11 @@
 
 	if("status" in signal.data)
 		broadcast_status()
-		return // do not update_icon
+		return // do not update_appearance
 
 		// log_admin("DEBUG \[[world.timeofday]\]: vent_pump/receive_signal: unknown command \"[signal.data["command"]]\"\n[signal.debug_print()]")
 	broadcast_status()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/components/unary/vent_pump/welder_act(mob/living/user, obj/item/I)
 	..()
@@ -264,7 +264,7 @@
 		else
 			user.visible_message("<span class='notice'>[user] unwelded the vent.</span>", "<span class='notice'>You unweld the vent.</span>", "<span class='hear'>You hear welding.</span>")
 			welded = FALSE
-		update_icon()
+		update_appearance()
 		pipe_vision_img = image(src, loc, layer = ABOVE_HUD_LAYER, dir = dir)
 		pipe_vision_img.plane = ABOVE_HUD_PLANE
 		investigate_log("was [welded ? "welded shut" : "unwelded"] by [key_name(user)]", INVESTIGATE_ATMOS)
@@ -294,7 +294,7 @@
 		return
 	user.visible_message("<span class='warning'>[user] furiously claws at [src]!</span>", "<span class='notice'>You manage to clear away the stuff blocking the vent.</span>", "<span class='hear'>You hear loud scraping noises.</span>")
 	welded = FALSE
-	update_icon()
+	update_appearance()
 	pipe_vision_img = image(src, loc, layer = ABOVE_HUD_LAYER, dir = dir)
 	pipe_vision_img.plane = ABOVE_HUD_PLANE
 	playsound(loc, 'sound/weapons/bladeslice.ogg', 100, TRUE)

code/modules/atmospherics/machinery/components/unary_devices/vent_scrubber.dm

@@ -255,10 +255,10 @@
 
 	if("status" in signal.data)
 		broadcast_status()
-		return //do not update_icon
+		return //do not update_appearance
 
 	broadcast_status()
-	update_icon()
+	update_appearance()
 	return
 
 /obj/machinery/atmospherics/components/unary/vent_scrubber/power_change()
@@ -277,7 +277,7 @@
 		else
 			user.visible_message("<span class='notice'>[user] unwelds the scrubber.</span>", "<span class='notice'>You unweld the scrubber.</span>", "<span class='hear'>You hear welding.</span>")
 			welded = FALSE
-		update_icon()
+		update_appearance()
 		pipe_vision_img = image(src, loc, layer = ABOVE_HUD_LAYER, dir = dir)
 		pipe_vision_img.plane = ABOVE_HUD_PLANE
 		investigate_log("was [welded ? "welded shut" : "unwelded"] by [key_name(user)]", INVESTIGATE_ATMOS)
@@ -303,7 +303,7 @@
 		return
 	user.visible_message("<span class='warning'>[user] furiously claws at [src]!</span>", "<span class='notice'>You manage to clear away the stuff blocking the scrubber.</span>", "<span class='hear'>You hear loud scraping noises.</span>")
 	welded = FALSE
-	update_icon()
+	update_appearance()
 	pipe_vision_img = image(src, loc, layer = ABOVE_HUD_LAYER, dir = dir)
 	pipe_vision_img.plane = ABOVE_HUD_PLANE
 	playsound(loc, 'sound/weapons/bladeslice.ogg', 100, TRUE)

code/modules/atmospherics/machinery/other/miner.dm

@@ -72,12 +72,12 @@
 /obj/machinery/atmospherics/miner/proc/set_active(setting)
 	if(active != setting)
 		active = setting
-		update_icon()
+		update_appearance()
 
 /obj/machinery/atmospherics/miner/proc/set_broken(setting)
 	if(broken != setting)
 		broken = setting
-		update_icon()
+		update_appearance()
 
 /obj/machinery/atmospherics/miner/proc/update_power()
 	if(!active)
@@ -113,7 +113,9 @@
 	. = ..()
 	if(broken)
 		. += "broken"
-	else if(active)
+		return
+
+	if(active)
 		var/mutable_appearance/on_overlay = mutable_appearance(icon, "on")
 		on_overlay.color = overlay_color
 		. += on_overlay

code/modules/atmospherics/machinery/pipes/heat_exchange/junction.dm

@@ -30,9 +30,9 @@
 		return ..(target, given_layer, FALSE) //we want a normal pipe instead
 	return ..(target, given_layer, TRUE)
 
-/obj/machinery/atmospherics/pipe/heat_exchanging/junction/update_icon()
+/obj/machinery/atmospherics/pipe/heat_exchanging/junction/update_icon_state()
 	icon_state = "pipe[nodes[1] ? "1" : "0"][nodes[2] ? "1" : "0"]-[piping_layer]"
-	update_layer()
+	return ..()
 
 /obj/machinery/atmospherics/pipe/heat_exchanging/junction/layer2
 	piping_layer = 2

code/modules/atmospherics/machinery/pipes/heat_exchange/manifold.dm

@@ -26,18 +26,16 @@
 	initialize_directions = ALL_CARDINALS
 	initialize_directions &= ~dir
 
-/obj/machinery/atmospherics/pipe/heat_exchanging/manifold/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/heat_exchanging/manifold/update_overlays()
+	. = ..()
 
 	PIPING_LAYER_DOUBLE_SHIFT(center, piping_layer)
-	add_overlay(center)
+	. += center
 
 	//Add non-broken pieces
 	for(var/i in 1 to device_type)
 		if(nodes[i])
-			add_overlay( getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i])) )
-
-	update_layer()
+			. += getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i]))
 
 /obj/machinery/atmospherics/pipe/heat_exchanging/manifold/layer2
 	piping_layer = 2

code/modules/atmospherics/machinery/pipes/heat_exchange/manifold4w.dm

@@ -24,18 +24,16 @@
 /obj/machinery/atmospherics/pipe/heat_exchanging/manifold4w/SetInitDirections()
 	initialize_directions = initial(initialize_directions)
 
-/obj/machinery/atmospherics/pipe/heat_exchanging/manifold4w/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/heat_exchanging/manifold4w/update_overlays()
+	. = ..()
 
 	PIPING_LAYER_DOUBLE_SHIFT(center, piping_layer)
-	add_overlay(center)
+	. += center
 
 	//Add non-broken pieces
 	for(var/i in 1 to device_type)
 		if(nodes[i])
-			add_overlay( getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i])) )
-
-	update_layer()
+			. += getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i]))
 
 /obj/machinery/atmospherics/pipe/heat_exchanging/manifold4w/layer2
 	piping_layer = 2

code/modules/atmospherics/machinery/pipes/heat_exchange/simple.dm

@@ -24,9 +24,9 @@
 		if(EAST, WEST)
 			initialize_directions = EAST|WEST
 
-/obj/machinery/atmospherics/pipe/heat_exchanging/simple/update_icon()
+/obj/machinery/atmospherics/pipe/heat_exchanging/simple/update_icon_state()
 	icon_state = "pipe[nodes[1] ? "1" : "0"][nodes[2] ? "1" : "0"]-[piping_layer]"
-	update_layer()
+	return ..()
 
 /obj/machinery/atmospherics/pipe/heat_exchanging/simple/layer2
 	piping_layer = 2

code/modules/atmospherics/machinery/pipes/layermanifold.dm

@@ -38,35 +38,33 @@
 /obj/machinery/atmospherics/pipe/layer_manifold/proc/get_all_connected_nodes()
 	return front_nodes + back_nodes + nodes
 
-/obj/machinery/atmospherics/pipe/layer_manifold/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/layer_manifold/update_layer()
 	layer = initial(layer) + (PIPING_LAYER_MAX * PIPING_LAYER_LCHANGE) //This is above everything else.
 
-	for(var/node in front_nodes)
-		add_attached_images(node)
-	for(var/node in back_nodes)
-		add_attached_images(node)
+/obj/machinery/atmospherics/pipe/layer_manifold/update_overlays()
+	. = ..()
 
-/obj/machinery/atmospherics/pipe/layer_manifold/proc/add_attached_images(obj/machinery/atmospherics/A)
+	for(var/node in front_nodes)
+		. += get_attached_images(node)
+	for(var/node in back_nodes)
+		. += get_attached_images(node)
+
+/obj/machinery/atmospherics/pipe/layer_manifold/proc/get_attached_images(obj/machinery/atmospherics/A)
 	if(!A)
 		return
+
+	. = list()
 	if(istype(A, /obj/machinery/atmospherics/pipe/layer_manifold))
 		for(var/i in PIPING_LAYER_MIN to PIPING_LAYER_MAX)
-			add_attached_image(get_dir(src, A), i)
-			return
-	add_attached_image(get_dir(src, A), A.piping_layer, A.pipe_color)
-
-/obj/machinery/atmospherics/pipe/layer_manifold/proc/add_attached_image(p_dir, p_layer, p_color = null)
-	var/image/I
+			. += get_attached_image(get_dir(src, A), i)
+		return
+	. += get_attached_image(get_dir(src, A), A.piping_layer, A.pipe_color)
 
+/obj/machinery/atmospherics/pipe/layer_manifold/proc/get_attached_image(p_dir, p_layer, p_color = null)
 	// Uses pipe-3 because we don't want the vertical shifting
-	if(p_color)
-		I = getpipeimage(icon, "pipe-3", p_dir, p_color, piping_layer = p_layer)
-	else
-		I = getpipeimage(icon, "pipe-3", p_dir, piping_layer = p_layer)
-
+	var/image/I = getpipeimage(icon, "pipe-3", p_dir, p_color, p_layer)
 	I.layer = layer - 0.01
-	add_overlay(I)
+	return I
 
 /obj/machinery/atmospherics/pipe/layer_manifold/SetInitDirections()
 	switch(dir)
@@ -93,7 +91,7 @@
 			new_nodes += foundfront
 		if(foundback && !QDELETED(foundback))
 			new_nodes += foundback
-	update_icon()
+	update_appearance()
 	return new_nodes
 
 /obj/machinery/atmospherics/pipe/layer_manifold/atmosinit()
@@ -120,7 +118,7 @@
 		if(reference in back_nodes)
 			var/i = back_nodes.Find(reference)
 			back_nodes[i] = null
-	update_icon()
+	update_appearance()
 
 /obj/machinery/atmospherics/pipe/layer_manifold/relaymove(mob/living/user, direction)
 	if(initialize_directions & direction)

code/modules/atmospherics/machinery/pipes/manifold.dm

@@ -30,16 +30,15 @@
 	initialize_directions = ALL_CARDINALS
 	initialize_directions &= ~dir
 
-/obj/machinery/atmospherics/pipe/manifold/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/manifold/update_overlays()
+	. = ..()
+
 	if(!center)
 		center = mutable_appearance(icon, "manifold_center")
 	PIPING_LAYER_DOUBLE_SHIFT(center, piping_layer)
-	add_overlay(center)
+	. += center
 
 	//Add non-broken pieces
 	for(var/i in 1 to device_type)
 		if(nodes[i])
-			add_overlay( getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i])) )
-
-	update_layer()
+			. += getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i]))

code/modules/atmospherics/machinery/pipes/manifold4w.dm

@@ -24,16 +24,14 @@
 /obj/machinery/atmospherics/pipe/manifold4w/SetInitDirections()
 	initialize_directions = initial(initialize_directions)
 
-/obj/machinery/atmospherics/pipe/manifold4w/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/manifold4w/update_overlays()
+	. = ..()
 	if(!center)
 		center = mutable_appearance(icon, "manifold_center")
 	PIPING_LAYER_DOUBLE_SHIFT(center, piping_layer)
-	add_overlay(center)
+	. += center
 
 	//Add non-broken pieces
 	for(var/i in 1 to device_type)
 		if(nodes[i])
-			add_overlay( getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i])) )
-
-	update_layer()
+			. += getpipeimage(icon, "pipe-[piping_layer]", get_dir(src, nodes[i]))

code/modules/atmospherics/machinery/pipes/multiz.dm

@@ -32,13 +32,17 @@
 /obj/machinery/atmospherics/pipe/multiz/SetInitDirections()
 	initialize_directions = dir
 
-/obj/machinery/atmospherics/pipe/multiz/update_icon()
-	cut_overlays()
+/obj/machinery/atmospherics/pipe/multiz/update_layer()
+	return // Noop because we're moving this to /obj/machinery/atmospherics/pipe
+
+/obj/machinery/atmospherics/pipe/multiz/update_overlays()
+	. = ..()
 	pipe.color = front_node ? front_node.pipe_color : rgb(255, 255, 255)
 	pipe.icon_state = "pipe-[piping_layer]"
+	. += pipe
 	center.pixel_x = PIPING_LAYER_P_X * (piping_layer - PIPING_LAYER_DEFAULT)
-	add_overlay(pipe)
-	add_overlay(center)
+	. += center
+
 
 ///Attempts to locate a multiz pipe that's above us, if it finds one it merges us into its pipenet
 /obj/machinery/atmospherics/pipe/multiz/pipeline_expansion()

code/modules/atmospherics/machinery/pipes/pipes.dm

@@ -83,6 +83,10 @@
 			qdel(meter)
 	. = ..()
 
+/obj/machinery/atmospherics/pipe/update_icon()
+	. = ..()
+	update_layer()
+
 /obj/machinery/atmospherics/pipe/proc/update_node_icon()
 	for(var/i in 1 to device_type)
 		if(nodes[i])

code/modules/atmospherics/machinery/pipes/simple.dm

@@ -27,6 +27,6 @@
 		if(EAST, WEST)
 			initialize_directions = EAST|WEST
 
-/obj/machinery/atmospherics/pipe/simple/update_icon()
+/obj/machinery/atmospherics/pipe/simple/update_icon_state()
 	icon_state = "pipe[nodes[1] ? "1" : "0"][nodes[2] ? "1" : "0"]-[piping_layer]"
-	update_layer()
+	return ..()

code/modules/atmospherics/machinery/portable/canister.dm

@@ -275,7 +275,7 @@
 	timing = !timing
 	if(timing)
 		valve_timer = world.time + (timer_set * 10)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/portable_atmospherics/canister/proto
 	name = "prototype canister"
@@ -330,7 +330,7 @@
 		air_contents.copy_from(existing_mixture)
 	else
 		create_gas()
-	update_icon()
+	update_appearance()
 
 
 /obj/machinery/portable_atmospherics/canister/proc/create_gas()
@@ -350,6 +350,7 @@
 /obj/machinery/portable_atmospherics/canister/update_icon_state()
 	if(machine_stat & BROKEN)
 		icon_state = "[base_icon_state]-1"
+	return ..()
 
 /obj/machinery/portable_atmospherics/canister/update_overlays()
 	. = ..()
@@ -362,15 +363,16 @@
 		. += "can-open"
 	if(connected_port)
 		. += "can-connector"
-	var/pressure = air_contents.return_pressure()
-	if(pressure >= 40 * ONE_ATMOSPHERE)
-		. += "can-3"
-	else if(pressure >= 10 * ONE_ATMOSPHERE)
-		. += "can-2"
-	else if(pressure >= 5 * ONE_ATMOSPHERE)
-		. += "can-1"
-	else if(pressure >= 10)
-		. += "can-0"
+
+	switch(air_contents.return_pressure())
+		if((40 * ONE_ATMOSPHERE) to INFINITY)
+			. += "can-3"
+		if((10 * ONE_ATMOSPHERE) to (40 * ONE_ATMOSPHERE))
+			. += "can-2"
+		if((5 * ONE_ATMOSPHERE) to (10 * ONE_ATMOSPHERE))
+			. += "can-1"
+		if((10) to (5 * ONE_ATMOSPHERE))
+			. += "can-0"
 
 
 /obj/machinery/portable_atmospherics/canister/should_atmos_process(datum/gas_mixture/air, exposed_temperature)
@@ -444,7 +446,7 @@
 	if(.)
 		if(close_valve)
 			valve_open = FALSE
-			update_icon()
+			update_appearance()
 			investigate_log("Valve was <b>closed</b> by [key_name(user)].", INVESTIGATE_ATMOS)
 		else if(valve_open && holding)
 			investigate_log("[key_name(user)] started a transfer into [holding].", INVESTIGATE_ATMOS)
@@ -471,7 +473,7 @@
 	///function used to check the limit of the canisters and also set the amount of damage that the canister can receive, if the heat and pressure are way higher than the limit the more damage will be done
 	if(our_temperature > heat_limit || our_pressure > pressure_limit)
 		take_damage(clamp((our_temperature/heat_limit) * (our_pressure/pressure_limit) * delta_time * 2, 5, 50), BURN, 0)
-	update_icon()
+	update_appearance()
 
 /obj/machinery/portable_atmospherics/canister/ui_state(mob/user)
 	return GLOB.physical_state
@@ -619,4 +621,4 @@
 					investigate_log("[key_name(usr)] removed the [holding], leaving the valve open and transferring into the <span class='boldannounce'>air</span>.", INVESTIGATE_ATMOS)
 				replace_tank(usr, FALSE)
 				. = TRUE
-	update_icon()
+	update_appearance()

code/modules/atmospherics/machinery/portable/portable_atmospherics.dm

@@ -70,7 +70,7 @@
 	anchored = TRUE //Prevent movement
 	pixel_x = new_port.pixel_x
 	pixel_y = new_port.pixel_y
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/machinery/portable_atmospherics/Move()
@@ -86,7 +86,7 @@
 	connected_port = null
 	pixel_x = 0
 	pixel_y = 0
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/machinery/portable_atmospherics/AltClick(mob/living/user)
@@ -111,7 +111,7 @@
 		holding = null
 	if(new_tank)
 		holding = new_tank
-	update_icon()
+	update_appearance()
 	return TRUE
 
 /obj/machinery/portable_atmospherics/attackby(obj/item/W, mob/user, params)
@@ -123,7 +123,7 @@
 			to_chat(user, "<span class='notice'>[holding ? "In one smooth motion you pop [holding] out of [src]'s connector and replace it with [T]" : "You insert [T] into [src]"].</span>")
 			investigate_log("had its internal [holding] swapped with [T] by [key_name(user)].", INVESTIGATE_ATMOS)
 			replace_tank(user, FALSE, T)
-			update_icon()
+			update_appearance()
 	else if(W.tool_behaviour == TOOL_WRENCH)
 		if(!(machine_stat & BROKEN))
 			if(connected_port)
@@ -134,7 +134,7 @@
 					"[user] disconnects [src].", \
 					"<span class='notice'>You unfasten [src] from the port.</span>", \
 					"<span class='hear'>You hear a ratchet.</span>")
-				update_icon()
+				update_appearance()
 				return
 			else
 				var/obj/machinery/atmospherics/components/unary/portables_connector/possible_port = locate(/obj/machinery/atmospherics/components/unary/portables_connector) in loc
@@ -149,7 +149,7 @@
 					"[user] connects [src].", \
 					"<span class='notice'>You fasten [src] to the port.</span>", \
 					"<span class='hear'>You hear a ratchet.</span>")
-				update_icon()
+				update_appearance()
 				investigate_log("was connected to [possible_port] by [key_name(user)].", INVESTIGATE_ATMOS)
 	else
 		return ..()

code/modules/atmospherics/machinery/portable/pump.dm

@@ -29,6 +29,7 @@
 
 /obj/machinery/portable_atmospherics/pump/update_icon_state()
 	icon_state = "psiphon:[on]"
+	return ..()
 
 /obj/machinery/portable_atmospherics/pump/update_overlays()
 	. = ..()
@@ -74,7 +75,7 @@
 		if(prob(100 / severity))
 			direction = PUMP_OUT
 		target_pressure = rand(0, 100 * ONE_ATMOSPHERE)
-		update_icon()
+		update_appearance()
 
 /obj/machinery/portable_atmospherics/pump/replace_tank(mob/living/user, close_valve)
 	. = ..()
@@ -82,7 +83,7 @@
 		if(close_valve)
 			if(on)
 				on = FALSE
-				update_icon()
+				update_appearance()
 		else if(on && holding && direction == PUMP_OUT)
 			investigate_log("[key_name(user)] started a transfer into [holding].", INVESTIGATE_ATMOS)
 
@@ -156,4 +157,4 @@
 			if(holding)
 				replace_tank(usr, FALSE)
 				. = TRUE
-	update_icon()
+	update_appearance()

code/modules/atmospherics/machinery/portable/scrubber.dm

@@ -38,6 +38,7 @@
 
 /obj/machinery/portable_atmospherics/scrubber/update_icon_state()
 	icon_state = "pscrubber:[on]"
+	return ..()
 
 /obj/machinery/portable_atmospherics/scrubber/update_overlays()
 	. = ..()
@@ -97,7 +98,7 @@
 	if(is_operational)
 		if(prob(50 / severity))
 			on = !on
-		update_icon()
+		update_appearance()
 
 /obj/machinery/portable_atmospherics/scrubber/ui_interact(mob/user, datum/tgui/ui)
 	ui = SStgui.try_update_ui(user, src, ui)
@@ -131,7 +132,7 @@
 		if(close_valve)
 			if(on)
 				on = FALSE
-				update_icon()
+				update_appearance()
 		else if(on && holding)
 			investigate_log("[key_name(user)] started a transfer into [holding].", INVESTIGATE_ATMOS)
 
@@ -150,7 +151,7 @@
 		if("toggle_filter")
 			scrubbing ^= gas_id2path(params["val"])
 			. = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/machinery/portable_atmospherics/scrubber/huge
 	name = "huge air scrubber"
@@ -174,11 +175,12 @@
 
 /obj/machinery/portable_atmospherics/scrubber/huge/update_icon_state()
 	icon_state = "scrubber:[on]"
+	return ..()
 
 /obj/machinery/portable_atmospherics/scrubber/huge/process_atmos(delta_time)
 	if((!anchored && !movable) || !is_operational)
 		on = FALSE
-		update_icon()
+		update_appearance()
 	use_power = on ? ACTIVE_POWER_USE : IDLE_POWER_USE
 	if(!on)
 		return

code/modules/awaymissions/gateway.dm

@@ -176,7 +176,7 @@ GLOBAL_LIST_EMPTY(gateway_destinations)
 
 /obj/machinery/gateway/Initialize()
 	generate_destination()
-	update_icon()
+	update_appearance()
 	portal_visuals = new
 	vis_contents += portal_visuals
 	return ..()
@@ -193,7 +193,7 @@ GLOBAL_LIST_EMPTY(gateway_destinations)
 	dest.deactivate(src)
 	QDEL_NULL(portal)
 	use_power = IDLE_POWER_USE
-	update_icon()
+	update_appearance()
 	portal_visuals.reset_visuals()
 
 /obj/machinery/gateway/process()
@@ -201,6 +201,7 @@ GLOBAL_LIST_EMPTY(gateway_destinations)
 		if(target)
 			deactivate()
 		return
+
 /obj/machinery/gateway/safe_throw_at(atom/target, range, speed, mob/thrower, spin = TRUE, diagonals_first = FALSE, datum/callback/callback, force = MOVE_FORCE_STRONG, gentle = FALSE)
 	return
 
@@ -216,7 +217,7 @@ GLOBAL_LIST_EMPTY(gateway_destinations)
 	portal_visuals.setup_visuals(target)
 	generate_bumper()
 	use_power = ACTIVE_POWER_USE
-	update_icon()
+	update_appearance()
 
 /obj/machinery/gateway/proc/Transfer(atom/movable/AM)
 	if(!target || !target.incoming_pass_check(AM))

code/modules/awaymissions/mission_code/challenge.dm

@@ -20,6 +20,7 @@
 	desc = "A heavy duty industrial laser."
 	icon = 'icons/obj/singularity.dmi'
 	icon_state = "emitter_+a"
+	base_icon_state = "emitter_+a"
 	anchored = TRUE
 	density = TRUE
 	resistance_flags = INDESTRUCTIBLE | FIRE_PROOF | ACID_PROOF

code/modules/buildmode/buildmode.dm

@@ -130,12 +130,12 @@
 	close_switchstates()
 	mode = new newmode(src)
 	mode.enter_mode(src)
-	modebutton.update_icon()
+	modebutton.update_appearance()
 
 /datum/buildmode/proc/change_dir(newdir)
 	build_dir = newdir
 	close_dirswitch()
-	dirbutton.update_icon()
+	dirbutton.update_appearance()
 	return 1
 
 /datum/buildmode/proc/InterceptClickOn(mob/user, params, atom/object)

code/modules/buildmode/buttons.dm

@@ -24,11 +24,12 @@
 	else if(LAZYACCESS(modifiers, RIGHT_CLICK))
 		bd.mode.change_settings(usr.client)
 		
-	update_icon()
+	update_appearance()
 	return 1
 
 /atom/movable/screen/buildmode/mode/update_icon_state()
 	icon_state = bd.mode.get_button_iconstate()
+	return ..()
 
 /atom/movable/screen/buildmode/help
 	icon_state = "buildhelp"
@@ -46,10 +47,11 @@
 
 /atom/movable/screen/buildmode/bdir/update_icon_state()
 	dir = bd.build_dir
+	return ..()
 
 /atom/movable/screen/buildmode/bdir/Click()
 	bd.toggle_dirswitch()
-	update_icon()
+	update_appearance()
 	return 1
 
 // used to switch between modes

code/modules/cargo/centcom_podlauncher.dm

@@ -709,7 +709,7 @@
 	if (isnull(target_turf))
 		return
 	var/obj/structure/closet/supplypod/centcompod/toLaunch = DuplicateObject(temp_pod) //Duplicate the temp_pod (which we have been varediting or configuring with the UI) and store the result
-	toLaunch.update_icon()//we update_icon() here so that the door doesnt "flicker on" right after it lands
+	toLaunch.update_appearance()//we update_appearance() here so that the door doesnt "flicker on" right after it lands
 	var/shippingLane = GLOB.areas_by_type[/area/centcom/supplypod/supplypod_temp_holding]
 	toLaunch.forceMove(shippingLane)
 	if (launchClone) //We arent launching the actual items from the bay, rather we are creating clones and launching those

code/modules/cargo/expressconsole.dm

@@ -210,7 +210,7 @@
 						else
 							new /obj/effect/pod_landingzone(LZ, podType, SO)
 						. = TRUE
-						update_icon()
+						update_appearance()
 			else
 				if(SO.pack.get_cost() * (0.72*MAX_EMAG_ROCKETS) <= points_to_check) // bulk discount :^)
 					landingzone = GLOB.areas_by_type[pick(GLOB.the_station_areas)]  //override default landing zone
@@ -232,5 +232,5 @@
 							else
 								new /obj/effect/pod_landingzone(LZ, podType, SO)
 							. = TRUE
-							update_icon()
+							update_appearance()
 							CHECK_TICK

code/modules/cargo/gondolapod.dm

@@ -65,12 +65,12 @@
 
 /mob/living/simple_animal/pet/gondola/gondolapod/setOpened()
 	opened = TRUE
-	update_icon()
+	update_appearance()
 	addtimer(CALLBACK(src, /atom/.proc/setClosed), 50)
 
 /mob/living/simple_animal/pet/gondola/gondolapod/setClosed()
 	opened = FALSE
-	update_icon()
+	update_appearance()
 
 /mob/living/simple_animal/pet/gondola/gondolapod/death()
 	qdel(linked_pod) //Will cause the open() proc for the linked supplypod to be called with the "broken" parameter set to true, meaning that it will dump its contents on death

code/modules/cargo/order.dm

@@ -58,7 +58,7 @@
 	P.info += "Rank: [orderer_rank]<br/>"
 	P.info += "Comment: [reason]<br/>"
 
-	P.update_icon()
+	P.update_appearance()
 	return P
 
 /datum/supply_order/proc/generateManifest(obj/container, owner, packname) //generates-the-manifests.
@@ -96,13 +96,13 @@
 			while(--lost >= 0)
 				qdel(pick(container.contents))
 
-	P.update_icon()
+	P.update_appearance()
 	P.forceMove(container)
 
 	if(istype(container, /obj/structure/closet/crate))
 		var/obj/structure/closet/crate/C = container
 		C.manifest = P
-		C.update_icon()
+		C.update_appearance()
 	else
 		container.contents += P
 

code/modules/cargo/packs.dm

@@ -1840,7 +1840,7 @@
 				var/obj/item/pizzabox/infinite/fourfiveeight = new(C)
 				fourfiveeight.boxtag = P.boxtag
 				fourfiveeight.boxtag_set = TRUE
-				fourfiveeight.update_icon()
+				fourfiveeight.update_appearance()
 				qdel(P)
 				anomalous_box_provided = TRUE
 				log_game("An anomalous pizza box was provided in a pizza crate at during cargo delivery")
@@ -1875,7 +1875,7 @@
 			P.pizza = new replacement_type
 			P.boxtag = P.pizza.boxtag
 			P.boxtag_set = TRUE
-			P.update_icon()
+			P.update_appearance()
 
 /datum/supply_pack/organic/pizza/proc/anomalous_pizza_report()
 	print_command_report("[station_name()], our anomalous materials divison has reported a missing object that is highly likely to have been sent to your station during a routine cargo \

code/modules/cargo/supplypod.dm

@@ -107,7 +107,7 @@
 		door = "[base]_door"
 	else
 		door = FALSE
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/proc/SetReverseIcon()
 	fin_mask = "bottomfin"
@@ -115,7 +115,7 @@
 		icon_state = GLOB.podstyles[style][POD_BASE] + "_reverse"
 	pixel_x = initial(pixel_x)
 	transform = matrix()
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/proc/backToNonReverseIcon()
 	fin_mask = initial(fin_mask)
@@ -123,33 +123,35 @@
 		icon_state = GLOB.podstyles[style][POD_BASE]
 	pixel_x = initial(pixel_x)
 	transform = matrix()
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/closet_update_overlays(list/new_overlays)
 	return
 
 /obj/structure/closet/supplypod/update_overlays()
 	. = ..()
-	if (style == STYLE_INVISIBLE)
+	if(style == STYLE_INVISIBLE)
 		return
-	if (rubble)
+
+	if(rubble)
 		. += rubble.getForeground(src)
-	if (style == STYLE_SEETHROUGH)
-		for (var/atom/A in contents)
+
+	if(style == STYLE_SEETHROUGH)
+		for(var/atom/A in contents)
 			var/mutable_appearance/itemIcon = new(A)
 			itemIcon.transform = matrix().Translate(-1 * SUPPLYPOD_X_OFFSET, 0)
 			. += itemIcon
-		for (var/t in turfs_in_cargo)//T is just a turf's type
+		for(var/t in turfs_in_cargo)//T is just a turf's type
 			var/turf/turf_type = t
 			var/mutable_appearance/itemIcon = mutable_appearance(initial(turf_type.icon), initial(turf_type.icon_state))
 			itemIcon.transform = matrix().Translate(-1 * SUPPLYPOD_X_OFFSET, 0)
 			. += itemIcon
 		return
 
-	if (opened) //We're opened means all we have to worry about is masking a decal if we have one
-		if (!decal) //We don't have a decal to mask
+	if(opened) //We're opened means all we have to worry about is masking a decal if we have one
+		if(!decal) //We don't have a decal to mask
 			return
-		if (!door) //We have a decal but no door, so let's just add the decal
+		if(!door) //We have a decal but no door, so let's just add the decal
 			. += decal
 			return
 		var/icon/masked_decal = new(icon, decal) //The decal we want to apply
@@ -159,23 +161,25 @@
 		door_masker.Blend("#000000", ICON_SUBTRACT)
 		masked_decal.Blend(door_masker, ICON_ADD)
 		. += masked_decal
-	else //If we're closed
-		if (!door) //We have no door, lets see if we have a decal. If not, theres nothing we need to do
-			if (decal)
-				. += decal
-			return
-		else if (GLOB.podstyles[style][POD_SHAPE] != POD_SHAPE_NORML) //If we're not a normal pod shape (aka, if we don't have fins), just add the door without masking
-			. += door
-		else
-			var/icon/masked_door = new(icon, door) //The door we want to apply
-			var/icon/fin_masker = new(icon, "mask_[fin_mask]") //The fin shape we want to 'cut out' of the door
-			fin_masker.MapColors(0,0,0,1, 0,0,0,1, 0,0,0,1, 1,1,1,0, 0,0,0,1)
-			fin_masker.SwapColor("#ffffffff", null)
-			fin_masker.Blend("#000000", ICON_SUBTRACT)
-			masked_door.Blend(fin_masker, ICON_ADD)
-			. += masked_door
-		if (decal)
+		return
+
+	//If we're closed
+	if(!door) //We have no door, lets see if we have a decal. If not, theres nothing we need to do
+		if(decal)
 			. += decal
+		return
+	else if (GLOB.podstyles[style][POD_SHAPE] != POD_SHAPE_NORML) //If we're not a normal pod shape (aka, if we don't have fins), just add the door without masking
+		. += door
+	else
+		var/icon/masked_door = new(icon, door) //The door we want to apply
+		var/icon/fin_masker = new(icon, "mask_[fin_mask]") //The fin shape we want to 'cut out' of the door
+		fin_masker.MapColors(0,0,0,1, 0,0,0,1, 0,0,0,1, 1,1,1,0, 0,0,0,1)
+		fin_masker.SwapColor("#ffffffff", null)
+		fin_masker.Blend("#000000", ICON_SUBTRACT)
+		masked_door.Blend(fin_masker, ICON_ADD)
+		. += masked_door
+	if(decal)
+		. += decal
 
 /obj/structure/closet/supplypod/tool_interact(obj/item/W, mob/user)
 	if(bluespace) //We dont want to worry about interacting with bluespace pods, as they are due to delete themselves soon anyways.
@@ -408,17 +412,17 @@
 /obj/structure/closet/supplypod/setOpened() //Proc exists here, as well as in any atom that can assume the role of a "holder" of a supplypod. Check the open_pod() proc for more details
 	opened = TRUE
 	density = FALSE
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/extractionpod/setOpened()
 	opened = TRUE
 	density = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/setClosed() //Ditto
 	opened = FALSE
 	density = TRUE
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/proc/tryMakeRubble(turf/T) //Ditto
 	if (rubble_type == RUBBLE_NONE)
@@ -431,7 +435,7 @@
 		return
 	rubble = new /obj/effect/supplypod_rubble(T)
 	rubble.setStyle(rubble_type, src)
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/Moved()
 	deleteRubble()
@@ -440,7 +444,7 @@
 /obj/structure/closet/supplypod/proc/deleteRubble()
 	rubble?.fadeAway()
 	rubble = null
-	update_icon()
+	update_appearance()
 
 /obj/structure/closet/supplypod/proc/addGlow()
 	if (GLOB.podstyles[style][POD_SHAPE] != POD_SHAPE_NORML)
@@ -587,7 +591,7 @@
 
 /obj/effect/pod_landingzone/proc/beginLaunch(effectCircle) //Begin the animation for the pod falling. The effectCircle param determines whether the pod gets to come in from any descent angle
 	pod.addGlow()
-	pod.update_icon()
+	pod.update_appearance()
 	if (pod.style != STYLE_INVISIBLE)
 		pod.add_filter("motionblur",1,list("type"="motion_blur", "x"=0, "y"=3))
 	pod.forceMove(drop_location())

code/modules/cargo/supplypod_beacon.dm

@@ -29,16 +29,19 @@
 			playsound(src,'sound/machines/synth_no.ogg',50,FALSE)
 		if (SP_UNREADY)
 			ready = FALSE
-	update_icon()
+	update_appearance()
 
 /obj/item/supplypod_beacon/update_overlays()
 	. = ..()
-	if (launched)
+	if(launched)
 		. += "sp_green"
-	else if (ready)
+		return
+	if(ready)
 		. += "sp_yellow"
-	else if (linked)
+		return
+	if(linked)
 		. += "sp_orange"
+		return
 
 /obj/item/supplypod_beacon/proc/endLaunch()
 	launched = FALSE

code/modules/client/preferences_toggles.dm

@@ -321,7 +321,7 @@ GLOBAL_LIST_INIT(ghost_forms, sortList(list("ghost","ghostking","ghostian2","ske
 		prefs.save_preferences()
 		if(isobserver(mob))
 			var/mob/dead/observer/O = mob
-			O.update_icon(new_form)
+			O.update_icon(ALL, new_form)
 
 GLOBAL_LIST_INIT(ghost_orbits, list(GHOST_ORBIT_CIRCLE,GHOST_ORBIT_TRIANGLE,GHOST_ORBIT_SQUARE,GHOST_ORBIT_HEXAGON,GHOST_ORBIT_PENTAGON))
 
@@ -350,7 +350,7 @@ GLOBAL_LIST_INIT(ghost_orbits, list(GHOST_ORBIT_CIRCLE,GHOST_ORBIT_TRIANGLE,GHOS
 		prefs.save_preferences()
 		if(isobserver(mob))
 			var/mob/dead/observer/O = mob
-			O.update_icon()
+			O.update_appearance()
 
 /client/verb/pick_ghost_customization()
 	set name = "Ghost Customization"

code/modules/clothing/chameleon.dm

@@ -282,7 +282,7 @@
 	var/obj/item/pda/agent_pda = target
 	if(istype(agent_pda))
 		agent_pda.update_label()
-		agent_pda.update_icon()
+		agent_pda.update_appearance()
 
 /datum/action/item_action/chameleon/change/pda/apply_job_data(datum/job/job_datum)
 	..()

code/modules/clothing/clothing.dm

@@ -411,17 +411,19 @@
 
 /obj/item/clothing/update_overlays()
 	. = ..()
-	if(damaged_clothes)
-		var/index = "[REF(initial(icon))]-[initial(icon_state)]"
-		var/static/list/damaged_clothes_icons = list()
-		var/icon/damaged_clothes_icon = damaged_clothes_icons[index]
-		if(!damaged_clothes_icon)
-			damaged_clothes_icon = icon(initial(icon), initial(icon_state), , 1) //we only want to apply damaged effect to the initial icon_state for each object
-			damaged_clothes_icon.Blend("#fff", ICON_ADD) //fills the icon_state with white (except where it's transparent)
-			damaged_clothes_icon.Blend(icon('icons/effects/item_damage.dmi', "itemdamaged"), ICON_MULTIPLY) //adds damage effect and the remaining white areas become transparant
-			damaged_clothes_icon = fcopy_rsc(damaged_clothes_icon)
-			damaged_clothes_icons[index] = damaged_clothes_icon
-		. += damaged_clothes_icon
+	if(!damaged_clothes)
+		return
+
+	var/index = "[REF(initial(icon))]-[initial(icon_state)]"
+	var/static/list/damaged_clothes_icons = list()
+	var/icon/damaged_clothes_icon = damaged_clothes_icons[index]
+	if(!damaged_clothes_icon)
+		damaged_clothes_icon = icon(initial(icon), initial(icon_state), , 1) //we only want to apply damaged effect to the initial icon_state for each object
+		damaged_clothes_icon.Blend("#fff", ICON_ADD) //fills the icon_state with white (except where it's transparent)
+		damaged_clothes_icon.Blend(icon('icons/effects/item_damage.dmi', "itemdamaged"), ICON_MULTIPLY) //adds damage effect and the remaining white areas become transparant
+		damaged_clothes_icon = fcopy_rsc(damaged_clothes_icon)
+		damaged_clothes_icons[index] = damaged_clothes_icon
+	. += damaged_clothes_icon
 
 /*
 SEE_SELF  // can see self, no matter what

code/modules/clothing/glasses/_glasses.dm

@@ -341,11 +341,12 @@
 
 /obj/item/clothing/glasses/blindfold/white/equipped(mob/living/carbon/human/user, slot)
 	if(ishuman(user) && slot == ITEM_SLOT_EYES)
-		update_icon(user)
+		update_icon(ALL, user)
 		user.update_inv_glasses() //Color might have been changed by update_icon.
 	..()
 
-/obj/item/clothing/glasses/blindfold/white/update_icon(mob/living/carbon/human/user)
+/obj/item/clothing/glasses/blindfold/white/update_icon(updates=ALL, mob/living/carbon/human/user)
+	. = ..()
 	if(ishuman(user) && !colored_before)
 		add_atom_colour("#[user.eye_color]", FIXED_COLOUR_PRIORITY)
 		colored_before = TRUE

code/modules/clothing/glasses/engine_goggles.dm

@@ -25,7 +25,7 @@
 /obj/item/clothing/glasses/meson/engine/Initialize()
 	. = ..()
 	START_PROCESSING(SSobj, src)
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/glasses/meson/engine/ComponentInitialize()
 	. = ..()
@@ -66,7 +66,7 @@
 		if(H.glasses == src)
 			H.update_sight()
 
-	update_icon()
+	update_appearance()
 	for(var/X in actions)
 		var/datum/action/A = X
 		A.UpdateButtonIcon()
@@ -133,6 +133,7 @@
 
 /obj/item/clothing/glasses/meson/engine/update_icon_state()
 	icon_state = inhand_icon_state = "trayson-[mode]"
+	return ..()
 
 /obj/item/clothing/glasses/meson/engine/tray //atmos techs have lived far too long without tray goggles while those damned engineers get their dual-purpose gogles all to themselves
 	name = "optical t-ray scanner"

code/modules/clothing/head/hardhat.dm

@@ -34,10 +34,11 @@
 		turn_on(user)
 	else
 		turn_off(user)
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/hardhat/update_icon_state()
 	icon_state = inhand_icon_state = "hardhat[on]_[hat_type]"
+	return ..()
 
 /obj/item/clothing/head/hardhat/proc/turn_on(mob/user)
 	set_light_on(TRUE)
@@ -121,7 +122,7 @@
 
 /obj/item/clothing/head/hardhat/weldhat/Initialize()
 	. = ..()
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/hardhat/weldhat/attack_self(mob/living/user)
 	toggle_helmet_light(user)
@@ -133,7 +134,7 @@
 /obj/item/clothing/head/hardhat/weldhat/proc/toggle_welding_screen(mob/living/user)
 	if(weldingvisortoggle(user))
 		playsound(src, 'sound/mecha/mechmove03.ogg', 50, TRUE) //Visors don't just come from nothing
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/hardhat/weldhat/worn_overlays(isinhands)
 	. = ..()

code/modules/clothing/head/helmet.dm

@@ -46,7 +46,7 @@
 	if(A == attached_light)
 		set_attached_light(null)
 		update_helmlight()
-		update_icon()
+		update_appearance()
 		QDEL_NULL(alight)
 		qdel(A)
 	return ..()
@@ -397,7 +397,7 @@
 /obj/item/clothing/head/helmet/monkey_sentience/Initialize()
 	. = ..()
 	light_colors = rand(1,3)
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/helmet/monkey_sentience/examine(mob/user)
 	. = ..()
@@ -410,6 +410,7 @@
 
 /obj/item/clothing/head/helmet/monkey_sentience/update_icon_state()
 	icon_state = "[initial(icon_state)][light_colors][magnification ? "up" : ""]"
+	return ..()
 
 /obj/item/clothing/head/helmet/monkey_sentience/equipped(mob/user, slot)
 	. = ..()
@@ -493,6 +494,7 @@
 			state += "-flight" //etc.
 
 	icon_state = state
+	return ..()
 
 /obj/item/clothing/head/helmet/ui_action_click(mob/user, action)
 	if(istype(action, alight))
@@ -508,7 +510,7 @@
 				return
 			to_chat(user, "<span class='notice'>You click [S] into place on [src].</span>")
 			set_attached_light(S)
-			update_icon()
+			update_appearance()
 			update_helmlight()
 			alight = new(src)
 			if(loc == user)
@@ -528,7 +530,7 @@
 		var/obj/item/flashlight/removed_light = set_attached_light(null)
 		update_helmlight()
 		removed_light.update_brightness(user)
-		update_icon()
+		update_appearance()
 		user.update_inv_head()
 		QDEL_NULL(alight)
 		return TRUE
@@ -553,7 +555,7 @@
 
 /obj/item/clothing/head/helmet/proc/update_helmlight()
 	if(attached_light)
-		update_icon()
+		update_appearance()
 
 	for(var/X in actions)
 		var/datum/action/A = X

code/modules/clothing/head/misc_special.dm

@@ -167,11 +167,12 @@
 
 /obj/item/clothing/head/kitty/equipped(mob/living/carbon/human/user, slot)
 	if(ishuman(user) && slot == ITEM_SLOT_HEAD)
-		update_icon(user)
-		user.update_inv_head() //Color might have been changed by update_icon.
+		update_icon(ALL, user)
+		user.update_inv_head() //Color might have been changed by update_appearance.
 	..()
 
-/obj/item/clothing/head/kitty/update_icon(mob/living/carbon/human/user)
+/obj/item/clothing/head/kitty/update_icon(updates=ALL, mob/living/carbon/human/user)
+	. = ..()
 	if(ishuman(user))
 		add_atom_colour("#[user.hair_color]", FIXED_COLOUR_PRIORITY)
 
@@ -228,14 +229,13 @@
 
 /obj/item/clothing/head/wig/Initialize(mapload)
 	. = ..()
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/wig/update_icon_state()
 	var/datum/sprite_accessory/S = GLOB.hairstyles_list[hairstyle]
-	if(!S)
-		return
-	else
+	if(S)
 		icon_state = S.icon_state
+	return ..()
 
 
 /obj/item/clothing/head/wig/worn_overlays(isinhands = FALSE, file2use)
@@ -259,7 +259,7 @@
 		user.visible_message("<span class='notice'>[user] changes \the [src]'s hairstyle to [new_style].</span>", "<span class='notice'>You change \the [src]'s hairstyle to [new_style].</span>")
 	if(newcolor && newcolor != color) // only update if necessary
 		add_atom_colour(newcolor, FIXED_COLOUR_PRIORITY)
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/wig/afterattack(mob/living/carbon/human/target, mob/user)
 	. = ..()
@@ -267,7 +267,7 @@
 		to_chat(user, "<span class='notice'>You adjust the [src] to look just like [target.name]'s [target.hairstyle].</span>")
 		add_atom_colour("#[target.hair_color]", FIXED_COLOUR_PRIORITY)
 		hairstyle = target.hairstyle
-		update_icon()
+		update_appearance()
 
 /obj/item/clothing/head/wig/random/Initialize(mapload)
 	hairstyle = pick(GLOB.hairstyles_list - "Bald") //Don't want invisible wig
@@ -290,7 +290,7 @@
 	if(ishuman(user) && slot == ITEM_SLOT_HEAD)
 		if (color != "#[user.hair_color]") // only update if necessary
 			add_atom_colour("#[user.hair_color]", FIXED_COLOUR_PRIORITY)
-			update_icon()
+			update_appearance()
 		user.update_inv_head()
 
 /obj/item/clothing/head/bronze

code/modules/clothing/shoes/bananashoes.dm

@@ -30,7 +30,7 @@
 			on = !on
 			if(!always_noslip)
 				clothing_flags &= ~NOSLIP
-			update_icon()
+			update_appearance()
 			to_chat(loc, "<span class='warning'>You ran out of bananium!</span>")
 		else
 			new /obj/item/grown/bananapeel/specialpeel(get_step(src,turn(wearer.dir, 180))) //honk
@@ -52,7 +52,7 @@
 	var/datum/component/material_container/bananium = GetComponent(/datum/component/material_container)
 	if(bananium.get_material_amount(/datum/material/bananium))
 		on = !on
-		update_icon()
+		update_appearance()
 		to_chat(user, "<span class='notice'>You [on ? "activate" : "deactivate"] the prototype shoes.</span>")
 		if(!always_noslip)
 			if(on)
@@ -63,7 +63,5 @@
 		to_chat(user, "<span class='warning'>You need bananium to turn the prototype shoes on!</span>")
 
 /obj/item/clothing/shoes/clown_shoes/banana_shoes/update_icon_state()
-	if(on)
-		icon_state = "clown_prototype_on"
-	else
-		icon_state = "clown_prototype_off"
+	icon_state = "clown_prototype_[on ? "on" : "off"]"
+	return ..()

code/modules/clothing/shoes/miscellaneous.dm

@@ -346,7 +346,7 @@
 	else
 		worn_icon_state = "[initial(icon_state)]"
 	playsound(src, 'sound/weapons/tap.ogg', 10, TRUE)
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/shoes/wheelys/Destroy()
 	QDEL_NULL(wheels)

code/modules/clothing/spacesuits/hardsuit.dm

@@ -350,6 +350,7 @@
 
 /obj/item/clothing/head/helmet/space/hardsuit/syndi/update_icon_state()
 	icon_state = "hardsuit[on]-[hardsuit_type]"
+	return ..()
 
 /obj/item/clothing/head/helmet/space/hardsuit/syndi/Initialize()
 	. = ..()
@@ -379,7 +380,7 @@
 		flags_cover &= ~(HEADCOVERSEYES | HEADCOVERSMOUTH)
 		flags_inv &= ~visor_flags_inv
 		cold_protection &= ~HEAD
-	update_icon()
+	update_appearance()
 	playsound(src.loc, 'sound/mecha/mechmove03.ogg', 50, TRUE)
 	toggle_hardsuit_mode(user)
 	user.update_inv_head()
@@ -406,7 +407,7 @@
 			linkedsuit.cold_protection &= ~(CHEST | GROIN | LEGS | FEET | ARMS | HANDS)
 
 		linkedsuit.icon_state = "hardsuit[on]-[hardsuit_type]"
-		linkedsuit.update_icon()
+		linkedsuit.update_appearance()
 		user.update_inv_wear_suit()
 		user.update_inv_w_uniform()
 		user.update_equipment_speed_mods()

code/modules/clothing/spacesuits/plasmamen.dm

@@ -62,7 +62,7 @@
 /obj/item/clothing/head/helmet/space/plasmaman/Initialize()
 	. = ..()
 	visor_toggling()
-	update_icon()
+	update_appearance()
 
 /obj/item/clothing/head/helmet/space/plasmaman/AltClick(mob/user)
 	if(user.canUseTopic(src, BE_CLOSE))
@@ -74,10 +74,10 @@
 			to_chat(user, "<span class='notice'>Your helmet's torch can't pass through your welding visor!</span>")
 			helmet_on = FALSE
 			playsound(src, 'sound/mecha/mechmove03.ogg', 50, TRUE) //Visors don't just come from nothing
-			update_icon()
+			update_appearance()
 		else
 			playsound(src, 'sound/mecha/mechmove03.ogg', 50, TRUE) //Visors don't just come from nothing
-			update_icon()
+			update_appearance()
 
 /obj/item/clothing/head/helmet/space/plasmaman/update_overlays()
 	. = ..()
@@ -93,7 +93,7 @@
 				smile = TRUE
 				smile_color = CR.paint_color
 				to_chat(user, "You draw a smiley on the helmet visor.")
-				update_icon()
+				update_appearance()
 		else
 			to_chat(user, "<span class='warning'>Seems like someone already drew something on this helmet's visor!</span>")
 
@@ -112,7 +112,7 @@
 	. = ..()
 	if(smile && (clean_types & CLEAN_TYPE_PAINT))
 		smile = FALSE
-		update_icon()
+		update_appearance()
 		return TRUE
 
 /obj/item/clothing/head/helmet/space/plasmaman/attack_self(mob/user)

code/modules/detectivework/scanner.dm

@@ -52,7 +52,7 @@
 	P.info = text("<center><B>Forensic Record - (FR-[])</B></center><HR><BR>", frNum)
 	P.info += jointext(log, "<BR>")
 	P.info += "<HR><B>Notes:</B><BR>"
-	P.update_icon()
+	P.update_appearance()
 
 	if(ismob(loc))
 		var/mob/M = loc

code/modules/events/pirates.dm

@@ -131,7 +131,7 @@
 
 /obj/machinery/shuttle_scrambler/Initialize(mapload)
 	. = ..()
-	update_icon()
+	update_appearance()
 
 /obj/machinery/shuttle_scrambler/process()
 	if(active)
@@ -162,7 +162,7 @@
 		if(active || !user.canUseTopic(src, BE_CLOSE))
 			return
 		toggle_on(user)
-		update_icon()
+		update_appearance()
 		send_notification()
 	else
 		dump_loot(user)
@@ -192,10 +192,8 @@
 	STOP_PROCESSING(SSobj,src)
 
 /obj/machinery/shuttle_scrambler/update_icon_state()
-	if(active)
-		icon_state = "dominator-blue"
-	else
-		icon_state = "dominator"
+	icon_state = active ? "dominator-blue" : "dominator"
+	return ..()
 
 /obj/machinery/shuttle_scrambler/Destroy()
 	toggle_off()

code/modules/events/prison_break.dm

@@ -47,7 +47,7 @@
 			if(istype(O, /obj/structure/closet/secure_closet))
 				var/obj/structure/closet/secure_closet/temp = O
 				temp.locked = FALSE
-				temp.update_icon()
+				temp.update_appearance()
 			else if(istype(O, /obj/machinery/door/airlock))
 				var/obj/machinery/door/airlock/temp = O
 				if(temp.critical_machine) //Skip doors in critical positions, such as the SM chamber.

code/modules/events/shuttle_loan.dm

@@ -263,7 +263,7 @@
 	set_anchored(TRUE)
 	timer_set = rand(480, 600) //once the supply shuttle docks (after 5 minutes travel time), players have between 3-5 minutes to defuse the bomb
 	activate()
-	update_icon()
+	update_appearance()
 
 /obj/item/paper/fluff/cargo/bomb
 	name = "hastly scribbled note"

code/modules/events/stray_cargo.dm

@@ -53,7 +53,7 @@
 	var/datum/supply_pack/SP = new pack_type
 	var/obj/structure/closet/crate/crate = SP.generate(null)
 	crate.locked = FALSE //Unlock secure crates
-	crate.update_icon()
+	crate.update_appearance()
 	var/obj/structure/closet/supplypod/pod = make_pod()
 	new /obj/effect/pod_landingzone(LZ, pod, crate)
 

code/modules/flufftext/Hallucination.dm

@@ -135,7 +135,7 @@ GLOBAL_LIST_INIT(hallucination_list, list(
 		if(target.client)
 			target.client.images |= current_image
 
-/obj/effect/hallucination/simple/update_icon(new_state,new_icon,new_px=0,new_py=0)
+/obj/effect/hallucination/simple/update_icon(updates=ALL, new_state, new_icon, new_px=0, new_py=0)
 	image_state = new_state
 	if(new_icon)
 		image_icon = new_icon
@@ -143,6 +143,7 @@ GLOBAL_LIST_INIT(hallucination_list, list(
 		image_icon = initial(image_icon)
 	px = new_px
 	py = new_py
+	. = ..()
 	Show()
 
 /obj/effect/hallucination/simple/Moved(atom/OldLoc, Dir)
@@ -248,7 +249,7 @@ GLOBAL_LIST_INIT(hallucination_list, list(
 	name = "alien hunter ([rand(1, 1000)])"
 
 /obj/effect/hallucination/simple/xeno/throw_impact(atom/hit_atom, datum/thrownthing/throwingdatum)
-	update_icon("alienh_pounce")
+	update_icon(ALL, "alienh_pounce")
 	if(hit_atom == target && target.stat!=DEAD)
 		target.Paralyze(100)
 		target.visible_message("<span class='danger'>[target] flails around wildly.</span>","<span class='userdanger'>[name] pounces on you!</span>")

code/modules/food_and_drinks/drinks/drinks.dm

@@ -246,8 +246,8 @@
 	spillable = TRUE
 
 /obj/item/reagent_containers/food/drinks/mug/update_icon_state()
-	. = ..()
 	icon_state = reagents.total_volume ? "tea" : "tea_empty"
+	return ..()
 
 /obj/item/reagent_containers/food/drinks/mug/tea
 	name = "Duke Purple tea"
@@ -297,7 +297,7 @@
 	cap_overlay = mutable_appearance(icon, cap_icon_state)
 	if(cap_on)
 		spillable = FALSE
-		update_icon()
+		update_appearance()
 
 /obj/item/reagent_containers/food/drinks/waterbottle/update_overlays()
 	. = ..()
@@ -333,7 +333,7 @@
 		cap_on = TRUE
 		spillable = FALSE
 		to_chat(user, "<span class='notice'>You put the cap on [src].</span>")
-	update_icon()
+	update_appearance()
 
 /obj/item/reagent_containers/food/drinks/waterbottle/is_refillable()
 	if(cap_on)
@@ -415,7 +415,7 @@
 	list_reagents = list(random_reagent.type = 50)
 	. = ..()
 	desc +=  "<span class='notice'>The writing reads '[random_reagent.name]'.</span>"
-	update_icon()
+	update_appearance()
 
 /obj/item/reagent_containers/food/drinks/beer
 	name = "space beer"
@@ -449,8 +449,8 @@
 	isGlass = FALSE
 
 /obj/item/reagent_containers/food/drinks/sillycup/update_icon_state()
-	. = ..()
 	icon_state = reagents.total_volume ? "water_cup" : "water_cup_e"
+	return ..()
 
 /obj/item/reagent_containers/food/drinks/sillycup/smallcarton
 	name = "small carton"
@@ -458,44 +458,74 @@
 	icon_state = "juicebox"
 	volume = 15 //I figure if you have to craft these it should at least be slightly better than something you can get for free from a watercooler
 
+/// Reagent container icon updates, especially this one, are complete jank. I will need to rework them after this is merged.
 /obj/item/reagent_containers/food/drinks/sillycup/smallcarton/on_reagent_change(datum/reagents/holder, ...)
 	. = ..()
 	if(!length(reagents.reagent_list))
-		name = "small carton"
-		desc = "A small carton, intended for holding drinks."
-		foodtype = NONE
+		foodtype = NONE /// Why are food types on the _container_? TODO: move these to the reagents
 		return
 
-	switch(reagents.get_master_reagent_id()) // - [] TODO: Unshitcode this. Right now I'm just passing through and this really needs it's own dedicated PR.
+	switch(reagents.get_master_reagent_id())
 		if(/datum/reagent/consumable/orangejuice)
-			name = "orange juice box" // I know this shouldn't be here, but I really don't have the time to fix this right now. Blame the last guy
-			desc = "A great source of vitamins. Stay healthy!" // Ditto
-			foodtype = FRUIT | BREAKFAST // Ditto
+			foodtype = FRUIT | BREAKFAST
 		if(/datum/reagent/consumable/milk)
-			name = "carton of milk"
-			desc = "An excellent source of calcium for growing space explorers."
 			foodtype = DAIRY | BREAKFAST
 		if(/datum/reagent/consumable/applejuice)
-			name = "apple juice box"
-			desc = "Sweet apple juice. Don't be late for school!"
 			foodtype = FRUIT
 		if(/datum/reagent/consumable/grapejuice)
-			name = "grape juice box"
-			desc = "Tasty grape juice in a fun little container. Non-alcoholic!"
 			foodtype = FRUIT
 		if(/datum/reagent/consumable/pineapplejuice)
-			name = "pineapple juice box"
-			desc = "Why would you even want this?"
 			foodtype = FRUIT | PINEAPPLE
 		if(/datum/reagent/consumable/milk/chocolate_milk)
-			name = "carton of chocolate milk"
-			desc = "Milk for cool kids!"
 			foodtype = SUGAR
 		if(/datum/reagent/consumable/ethanol/eggnog)
-			name = "carton of eggnog"
-			desc = "For enjoying the most wonderful time of the year."
 			foodtype = MEAT
 
+/obj/item/reagent_containers/food/drinks/sillycup/smallcarton/update_name(updates)
+	. = ..()
+	if(!length(reagents.reagent_list))
+		name = "small carton"
+		return
+
+	switch(reagents.get_master_reagent_id())
+		if(/datum/reagent/consumable/orangejuice)
+			name = "orange juice box"
+		if(/datum/reagent/consumable/milk)
+			name = "carton of milk"
+		if(/datum/reagent/consumable/applejuice)
+			name = "apple juice box"
+		if(/datum/reagent/consumable/grapejuice)
+			name = "grape juice box"
+		if(/datum/reagent/consumable/pineapplejuice)
+			name = "pineapple juice box"
+		if(/datum/reagent/consumable/milk/chocolate_milk)
+			name = "carton of chocolate milk"
+		if(/datum/reagent/consumable/ethanol/eggnog)
+			name = "carton of eggnog"
+
+/obj/item/reagent_containers/food/drinks/sillycup/smallcarton/update_desc(updates)
+	. = ..()
+	if(!length(reagents.reagent_list))
+		desc = "A small carton, intended for holding drinks."
+		return
+
+	switch(reagents.get_master_reagent_id())
+		if(/datum/reagent/consumable/orangejuice)
+			desc = "A great source of vitamins. Stay healthy!"
+		if(/datum/reagent/consumable/milk)
+			desc = "An excellent source of calcium for growing space explorers."
+		if(/datum/reagent/consumable/applejuice)
+			desc = "Sweet apple juice. Don't be late for school!"
+		if(/datum/reagent/consumable/grapejuice)
+			desc = "Tasty grape juice in a fun little container. Non-alcoholic!"
+		if(/datum/reagent/consumable/pineapplejuice)
+			desc = "Why would you even want this?"
+		if(/datum/reagent/consumable/milk/chocolate_milk)
+			desc = "Milk for cool kids!"
+		if(/datum/reagent/consumable/ethanol/eggnog)
+			desc = "For enjoying the most wonderful time of the year."
+
+
 /obj/item/reagent_containers/food/drinks/sillycup/smallcarton/update_icon_state()
 	. = ..()
 	if(!length(reagents.reagent_list))

code/modules/food_and_drinks/drinks/drinks/drinkingglass.dm

@@ -19,26 +19,31 @@
 	. = ..()
 	if(!length(reagents.reagent_list))
 		renamedByPlayer = FALSE //so new drinks can rename the glass
-		return
 
+/obj/item/reagent_containers/food/drinks/drinkingglass/update_name(updates)
 	if(renamedByPlayer)
 		return
-
+	. = ..()
 	var/datum/reagent/largest_reagent = reagents.get_master_reagent()
-	name = largest_reagent.glass_name || initial(name)
-	desc = largest_reagent.glass_desc || initial(desc)
+	name = largest_reagent?.glass_name || initial(name)
+
+/obj/item/reagent_containers/food/drinks/drinkingglass/update_desc(updates)
+	if(renamedByPlayer)
+		return
+	. = ..()
+	var/datum/reagent/largest_reagent = reagents.get_master_reagent()
+	desc = largest_reagent?.glass_desc || initial(desc)
 
 /obj/item/reagent_containers/food/drinks/drinkingglass/update_icon_state()
-	. = ..()
 	if(!length(reagents.reagent_list))
 		icon_state = "glass_empty"
-		return
+		return ..()
 
 	var/datum/reagent/largest_reagent = reagents.get_master_reagent()
-	if(largest_reagent.glass_icon_state)
+	if(largest_reagent?.glass_icon_state)
 		icon_state = largest_reagent.glass_icon_state
 		icon = largest_reagent.glass_icon || 'icons/obj/drinks.dmi' //SKYRAT EDIT ADDITION - CUSTOMIZATION
-	return NONE
+	return ..()
 
 /obj/item/reagent_containers/food/drinks/drinkingglass/update_overlays()
 	. = ..()
@@ -60,6 +65,7 @@
 	name = "shot glass"
 	desc = "A shot glass - the universal symbol for bad decisions."
 	icon_state = "shotglass"
+	base_icon_state = "shotglass"
 	gulp_size = 15
 	amount_per_transfer_from_this = 15
 	possible_transfer_amounts = list()
@@ -67,32 +73,33 @@
 	custom_materials = list(/datum/material/glass=100)
 	custom_price = PAYCHECK_ASSISTANT * 0.4
 
-/obj/item/reagent_containers/food/drinks/drinkingglass/shotglass/on_reagent_change(datum/reagents/holder, ...)
+/obj/item/reagent_containers/food/drinks/drinkingglass/shotglass/update_name(updates)
+	if(renamedByPlayer)
+		return
+	. = ..()
+	name = "[length(reagents.reagent_list) ? "filled " : null]shot glass"
+
+/obj/item/reagent_containers/food/drinks/drinkingglass/shotglass/update_desc(updates)
+	if(renamedByPlayer)
+		return
 	. = ..()
 	if(!length(reagents.reagent_list))
-		name = "shot glass"
 		desc = "A shot glass - the universal symbol for bad decisions."
-		return
-
-	name = "filled shot glass"
-	desc = "The challenge is not taking as many as you can, but guessing what it is before you pass out."
+	else
+		desc = "The challenge is not taking as many as you can, but guessing what it is before you pass out."
 
 /obj/item/reagent_containers/food/drinks/drinkingglass/shotglass/update_icon_state()
 	. = ..()
 	if(!length(reagents.reagent_list))
-		icon_state = "shotglass"
-		name = "shot glass"
-		desc = "A shot glass - the universal symbol for bad decisions."
+		icon_state = base_icon_state
 		return
 
 	var/datum/reagent/largest_reagent = reagents.get_master_reagent()
-	name = "filled shot glass"
-	desc = "The challenge is not taking as many as you can, but guessing what it is before you pass out."
-	icon_state = largest_reagent.shot_glass_icon_state || "shotglassclear"
+	icon_state = largest_reagent.shot_glass_icon_state || "[base_icon_state]clear"
 
 /obj/item/reagent_containers/food/drinks/drinkingglass/shotglass/update_overlays()
 	. = ..()
-	if(icon_state != "shotglassclear")
+	if(icon_state != "[base_icon_state]clear")
 		return
 
 	var/mutable_appearance/shot_overlay = mutable_appearance(icon, "shotglassoverlay")