Port TG updating appearances (#17943)

* Get pants that match or else you gonna look silly yo

* Posters

* Fix other hud elements

* Rereviewed

* Update shotglass.dm

* Fix for new merged PRs

* Typo

* Coming across other stuff

* Update theblob.dm

* No takebacksies

* smh i forget to leave a comment

* Updated for the detgun and cards

* Should have rerun langserver again

* No longer plastic, more in scope

* Damn you bluespace

* Reverting turret logic, out of scope at this point

* Tweak that part

* Went over energy guns again, and fixed UI White's sprite sheet

* Welding masks, glasses, and JUSTICE

* Update portable_atmospherics.dm

* Cleaning up, clearing things up

* Review and suggestions

* Update valve.dm

* More tweaks

* Missing character

* Not distinct lightmasks, so they can be overlays

* Update generator.dm

* Add parameter so holodeck doesn't try to make a perfect copy

* Update unsorted.dm

* Spiders

* Better fix for spiders, fix vamps too

* Ghosts

* Update telekinesis.dm

* Cleaning up old procs

* It's set up to not copy datums... Unless they're in a list

* Donuts, duct tape, and detgun. D3VR coming to Early Access

* Update procs that interact with doors so they call update_state instead

* Forgot one spot, and actually might as well just force lock

* Cleaning up other things... Sigh, and kitty ears

* oops

* Getting used to how it works

* blinds

* Going back to the suit obscuring thing, so it doesn't update all the time

* Missed that from merging master

* I made this PR and forgot about it

* Fix runtimes in cards

* Make things a bit more unified

* Update update_icons.dm

* yarn, really?

* Update library_equipment.dm

* Update shieldgen.dm

* Every time Charlie merges something, I go back and see if I can improve things further

* what's this? more?

* Update misc_special.dm

* wow, paper

* Review

* More reviews

* To be sure, seems like being broken messed something sometimes

* Brought airlocks closer to how TG works to iron out some stuff

* Pizza and morgue

* Doesn't seem to hurt, tried with holodeck

* Revert "Doesn't seem to hurt, tried with holodeck"

This reverts commit 158529302b.

* Icon conflict

* Fix organ damage

* Don't ask how. Why. It's like that on prod too.

* Cutting down on things and updating from TG.

* More flexible. Just in case the thing you stuck it on didn't destroy.

* Hydro was one the things I touched earlier on, better rework it

* Reviews

* Cleaning up further, also bri'ish

* Undo a change I did, and switch over to a more recent implementation

* Update biogenerator.dm

* Rolling back to old airlocks, but with new duct taped note

* Functionally the same. I'd just rather not have the smoothing happen there

* Went over APCs again

* Fix welding helmet names in species files

* Update airlock.dm

* Update persistent_overlay.dm

* Oh, topic

code/game/objects/effects/decals/Cleanable/aliens.dm

@@ -19,6 +19,7 @@
 
 /obj/effect/decal/cleanable/blood/gibs/xeno/update_icon()
 	color = "#FFFFFF"
+	. = ..()
 
 /obj/effect/decal/cleanable/blood/gibs/xeno/up
 	random_icon_states = list("xgib1", "xgib2", "xgib3", "xgib4", "xgib5", "xgib6", "xgibup1", "xgibup1", "xgibup1")

code/game/objects/effects/decals/Cleanable/humans.dm

@@ -50,6 +50,7 @@ GLOBAL_LIST_EMPTY(splatter_cache)
 	if(basecolor == "rainbow")
 		basecolor = "#[pick(list("FF0000","FF7F00","FFFF00","00FF00","0000FF","4B0082","8F00FF"))]"
 	color = basecolor
+	..()
 
 /obj/effect/decal/cleanable/blood/proc/dry()
 	name = dryname
@@ -142,21 +143,26 @@ GLOBAL_LIST_EMPTY(splatter_cache)
 	random_icon_states = list("gib1", "gib2", "gib3", "gib4", "gib5", "gib6")
 	no_clear = TRUE
 	mergeable_decal = FALSE
-
+	var/image/giblets
 	var/fleshcolor = "#FFFFFF"
 
+/obj/effect/decal/cleanable/blood/gibs/Destroy()
+	giblets = null
+	return ..()
+
 /obj/effect/decal/cleanable/blood/gibs/update_icon()
-	var/image/giblets = new(base_icon, "[icon_state]_flesh", dir)
+	giblets = new(base_icon, "[icon_state]_flesh", dir)
 	if(!fleshcolor || fleshcolor == "rainbow")
 		fleshcolor = "#[pick(list("FF0000","FF7F00","FFFF00","00FF00","0000FF","4B0082","8F00FF"))]"
 	giblets.color = fleshcolor
 	var/icon/blood = new(base_icon,"[icon_state]",dir)
-
 	icon = blood
-	overlays.Cut()
-	overlays += giblets
 	. = ..()
 
+/obj/effect/decal/cleanable/blood/gibs/update_overlays()
+	. = ..()
+	. += giblets
+
 /obj/effect/decal/cleanable/blood/gibs/ex_act(severity)
 	return
 

code/game/objects/effects/decals/Cleanable/robots.dm

@@ -13,6 +13,7 @@
 
 /obj/effect/decal/cleanable/blood/gibs/robot/update_icon()
 	color = "#FFFFFF"
+	. = ..()
 
 /obj/effect/decal/cleanable/blood/gibs/robot/dry()	//pieces of robots do not dry up like
 	return

code/game/objects/effects/decals/Cleanable/tracks.dm

@@ -87,8 +87,8 @@ GLOBAL_LIST_EMPTY(fluidtrack_cache)
 				update_icon()
 
 
-/obj/effect/decal/cleanable/blood/footprints/update_icon()
-	overlays.Cut()
+/obj/effect/decal/cleanable/blood/footprints/update_overlays()
+	. = ..()
 
 	for(var/Ddir in GLOB.cardinal)
 		if(entered_dirs & Ddir)
@@ -100,7 +100,7 @@ GLOBAL_LIST_EMPTY(fluidtrack_cache)
 				GLOB.fluidtrack_cache["entered-[blood_state]-[Ddir]"] = I
 			if(I)
 				I.color = basecolor
-				overlays += I
+				. += I
 		if(exited_dirs & Ddir)
 			var/image/I
 			if(GLOB.fluidtrack_cache["exited-[blood_state]-[Ddir]"])
@@ -110,7 +110,7 @@ GLOBAL_LIST_EMPTY(fluidtrack_cache)
 				GLOB.fluidtrack_cache["exited-[blood_state]-[Ddir]"] = I
 			if(I)
 				I.color = basecolor
-				overlays += I
+				. += I
 
 	alpha = base_alpha + bloodiness
 

code/game/objects/effects/decals/contraband.dm

@@ -62,9 +62,9 @@
 	var/poster_item_icon_state = "rolled_poster"
 
 /obj/structure/sign/poster/Initialize(mapload)
-	. = ..()
 	if(random_basetype)
 		randomise(random_basetype)
+	. = ..()
 	if(!ruined)
 		original_name = name
 		name = "poster - [name]"

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

@@ -36,7 +36,7 @@
 
 			var/obj/structure/foamedmetal/M = new(src.loc)
 			M.metal = metal
-			M.updateicon()
+			M.update_state()
 
 		flick("[icon_state]-disolve", src)
 		sleep(5)
@@ -193,15 +193,20 @@
 /obj/structure/foamedmetal/play_attack_sound(damage_amount, damage_type = BRUTE, damage_flag = 0)
 	playsound(src.loc, 'sound/weapons/tap.ogg', 100, TRUE)
 
-/obj/structure/foamedmetal/proc/updateicon()
+/obj/structure/foamedmetal/proc/update_state()
 	if(metal == MFOAM_ALUMINUM)
-		icon_state = "metalfoam"
 		max_integrity = 20
 		obj_integrity = max_integrity
 	else
-		icon_state = "ironfoam"
 		max_integrity = 50
 		obj_integrity = max_integrity
+	update_icon(UPDATE_ICON_STATE)
+
+/obj/structure/foamedmetal/update_icon_state()
+	if(metal == MFOAM_ALUMINUM)
+		icon_state = "metalfoam"
+	else
+		icon_state = "ironfoam"
 
 /obj/structure/foamedmetal/attack_hand(mob/user)
 	user.changeNext_move(CLICK_CD_MELEE)

code/game/objects/items/ashtray.dm

@@ -30,19 +30,25 @@
 
 		visible_message("[user] places [I] in [src].")
 		add_fingerprint(user)
-		update_icon()
+		update_appearance(UPDATE_DESC|UPDATE_ICON_STATE)
 	else
 		return ..()
 
-/obj/item/ashtray/update_icon()
+/obj/item/ashtray/update_icon_state()
 	if(contents.len == max_butts)
 		icon_state = icon_full
-		desc = initial(desc) + " It's stuffed full."
 	else if(contents.len > max_butts * 0.5)
 		icon_state = icon_half
-		desc = initial(desc) + " It's half-filled."
 	else
 		icon_state = initial(icon_state)
+
+/obj/item/ashtray/update_desc()
+	. = ..()
+	if(contents.len == max_butts)
+		desc = initial(desc) + " It's stuffed full."
+	else if(contents.len > max_butts * 0.5)
+		desc = initial(desc) + " It's half-filled."
+	else
 		desc = initial(desc)
 
 /obj/item/ashtray/deconstruct()
@@ -52,7 +58,7 @@
 /obj/item/ashtray/proc/empty_tray()
 	for(var/obj/item/I in contents)
 		I.forceMove(loc)
-	update_icon()
+	update_appearance(UPDATE_DESC|UPDATE_ICON_STATE)
 
 /obj/item/ashtray/throw_impact(atom/hit_atom)
 	if(contents.len)

code/game/objects/items/bodybag.dm

@@ -56,7 +56,7 @@
 /obj/structure/closet/body_bag/update_overlays()
 	..()
 	if(name != initial(name))
-		add_overlay("bodybag_label")
+		. += "bodybag_label"
 
 /obj/structure/closet/body_bag/MouseDrop(over_object, src_location, over_location)
 	. = ..()

code/game/objects/items/candle.dm

@@ -22,7 +22,7 @@
 	STOP_PROCESSING(SSobj, src)
 	return ..()
 
-/obj/item/candle/update_icon()
+/obj/item/candle/update_icon_state()
 	if(flickering)
 		icon_state = "candle[get_icon_index()]_flicker"
 	else
@@ -58,7 +58,7 @@
 			usr.visible_message(show_message)
 		set_light(CANDLE_LUM)
 		START_PROCESSING(SSobj, src)
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/item/candle/proc/get_icon_index()
 	if(wax > 150)
@@ -70,12 +70,12 @@
 
 /obj/item/candle/proc/start_flickering()
 	flickering = TRUE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	addtimer(CALLBACK(src, .proc/stop_flickering), 4 SECONDS, TIMER_UNIQUE)
 
 /obj/item/candle/proc/stop_flickering()
 	flickering = FALSE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/candle/process()
 	if(!lit)
@@ -88,7 +88,7 @@
 			var/mob/M = src.loc
 			M.unEquip(src, 1) //src is being deleted anyway
 		qdel(src)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	if(isturf(loc)) //start a fire if possible
 		var/turf/T = loc
 		T.hotspot_expose(700, 5)
@@ -98,7 +98,7 @@
 	if(lit)
 		user.visible_message("<span class='notice'>[user] snuffs out [src].</span>")
 		lit = FALSE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		set_light(0)
 
 /obj/item/candle/eternal

code/game/objects/items/crayons.dm

@@ -269,13 +269,12 @@
 		if("Toggle Cap")
 			to_chat(user, "<span class='notice'>You [capped ? "remove" : "replace"] the cap of [src].</span>")
 			capped = !capped
-			icon_state = "spraycan[capped ? "_cap" : ""]"
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 		if("Change Drawing")
 			..()
 		if("Change Color")
 			colour = input(user,"Choose Color") as color
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 
 /obj/item/toy/crayon/spraycan/afterattack(atom/target, mob/user as mob, proximity)
 	if(!proximity)
@@ -300,8 +299,11 @@
 		playsound(user.loc, 'sound/effects/spray.ogg', 5, 1, 5)
 		..()
 
-/obj/item/toy/crayon/spraycan/update_icon()
-	overlays.Cut()
+/obj/item/toy/crayon/spraycan/update_icon_state()
+	icon_state = "spraycan[capped ? "_cap" : ""]"
+
+/obj/item/toy/crayon/spraycan/update_overlays()
+	. = ..()
 	var/image/I = image('icons/obj/crayons.dmi',icon_state = "[capped ? "spraycan_cap_colors" : "spraycan_colors"]")
 	I.color = colour
-	overlays += I
+	. += I

code/game/objects/items/devices/flashlight.dm

@@ -15,34 +15,32 @@
 
 /obj/item/flashlight/Initialize()
 	. = ..()
-	if(on)
-		icon_state = "[initial(icon_state)]-on"
-		set_light(brightness_on)
-	else
-		icon_state = initial(icon_state)
-		set_light(0)
+	update_brightness()
 
-/obj/item/flashlight/proc/update_brightness(mob/user = null)
+/obj/item/flashlight/update_icon_state()
 	if(on)
 		icon_state = "[initial(icon_state)]-on"
+	else
+		icon_state = "[initial(icon_state)]"
+
+/obj/item/flashlight/proc/update_brightness()
+	if(on)
 		set_light(brightness_on)
 	else
-		icon_state = initial(icon_state)
 		set_light(0)
+	update_icon()
 
 /obj/item/flashlight/attack_self(mob/user)
 	if(!isturf(user.loc))
 		to_chat(user, "You cannot turn the light on while in this [user.loc].")//To prevent some lighting anomalities.
-
-		return 0
+		return FALSE
 	on = !on
 	playsound(user, togglesound, 100, 1)
-	update_brightness(user)
+	update_brightness()
 	for(var/X in actions)
 		var/datum/action/A = X
 		A.UpdateButtonIcon()
-	return 1
-
+	return TRUE
 
 /obj/item/flashlight/attack(mob/living/M as mob, mob/living/user as mob)
 	add_fingerprint(user)
@@ -129,15 +127,12 @@
 	materials = list()
 	on = TRUE
 
-
 // green-shaded desk lamp
 /obj/item/flashlight/lamp/green
 	desc = "A classic green-shaded desk lamp."
 	icon_state = "lampgreen"
 	item_state = "lampgreen"
 
-
-
 /obj/item/flashlight/lamp/verb/toggle_light()
 	set name = "Toggle light"
 	set category = "Object"
@@ -153,7 +148,6 @@
 	icon_state = "bananalamp"
 	item_state = "bananalamp"
 
-
 // FLARES
 
 /obj/item/flashlight/flare
@@ -174,6 +168,12 @@
 	fuel = rand(fuel_lower, fuel_upp)
 	..()
 
+/obj/item/flashlight/flare/update_icon_state()
+	if(!fuel)
+		icon_state = "[initial(icon_state)]-empty"
+		return
+	..()
+
 /obj/item/flashlight/flare/process()
 	var/turf/pos = get_turf(src)
 	if(pos && produce_heat)
@@ -181,8 +181,6 @@
 	fuel = max(fuel - 1, 0)
 	if(!fuel || !on)
 		turn_off()
-		if(!fuel)
-			icon_state = "[initial(icon_state)]-empty"
 		STOP_PROCESSING(SSobj, src)
 
 /obj/item/flashlight/flare/Destroy()
@@ -193,21 +191,9 @@
 	on = FALSE
 	force = initial(force)
 	damtype = initial(damtype)
-	if(ismob(loc))
-		var/mob/U = loc
-		update_brightness(U)
-	else
-		update_brightness(null)
-
-/obj/item/flashlight/flare/update_brightness(mob/user = null)
-	..()
-	if(on)
-		item_state = "[initial(item_state)]-on"
-	else
-		item_state = "[initial(item_state)]"
+	update_brightness()
 
 /obj/item/flashlight/flare/attack_self(mob/user)
-
 	// Usual checks
 	if(!fuel)
 		to_chat(user, "<span class='notice'>[src] is out of fuel.</span>")
@@ -220,8 +206,9 @@
 	// All good, turn it on.
 	if(.)
 		user.visible_message("<span class='notice'>[user] activates [src].</span>", "<span class='notice'>You activate [src].</span>")
-		force = on_damage
-		damtype = "fire"
+		if(produce_heat)
+			force = on_damage
+			damtype = "fire"
 		START_PROCESSING(SSobj, src)
 
 // GLOWSTICKS
@@ -234,30 +221,25 @@
 	icon_state = "glowstick"
 	item_state = "glowstick"
 	togglesound = 'sound/effects/bone_break_1.ogg'
-	produce_heat = 0
+	produce_heat = FALSE
 	fuel_lower = 1600
 	fuel_upp = 2000
+	blocks_emissive = FALSE
 
 /obj/item/flashlight/flare/glowstick/Initialize()
 	light_color = color
 	..()
 
-/obj/item/flashlight/flare/glowstick/update_icon()
-	item_state = "glowstick"
-	cut_overlays()
+/obj/item/flashlight/flare/glowstick/update_icon_state()
 	if(!fuel)
 		icon_state = "glowstick-empty"
-		cut_overlays()
-		update_brightness(0)
-	else if(on)
+
+/obj/item/flashlight/flare/glowstick/update_overlays()
+	. = ..()
+	if(on)
 		var/mutable_appearance/glowstick_overlay = mutable_appearance(icon, "glowstick-glow")
 		glowstick_overlay.color = color
-		add_overlay(glowstick_overlay)
-		item_state = "glowstick-on"
-		update_brightness(brightness_on)
-	else
-		icon_state = "glowstick"
-		cut_overlays()
+		. += glowstick_overlay
 
 /obj/item/flashlight/flare/glowstick/red
 	name = "red glowstick"

code/game/objects/items/devices/geiger_counter.dm

@@ -53,7 +53,7 @@
 
 	current_tick_amount = 0
 
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	update_sound()
 
 /obj/item/geiger_counter/examine(mob/user)
@@ -80,7 +80,7 @@
 
 	. += "<span class='notice'>The last radiation amount detected was [last_tick_amount]</span>"
 
-/obj/item/geiger_counter/update_icon()
+/obj/item/geiger_counter/update_icon_state()
 	if(!scanning)
 		icon_state = "geiger_off"
 	else if(emagged)
@@ -113,11 +113,11 @@
 	if(amount <= RAD_BACKGROUND_RADIATION || !scanning)
 		return
 	current_tick_amount += amount
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/geiger_counter/attack_self(mob/user)
 	scanning = !scanning
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	to_chat(user, "<span class='notice'>[bicon(src)] You switch [scanning ? "on" : "off"] [src].</span>")
 
 /obj/item/geiger_counter/afterattack(atom/target, mob/user)
@@ -158,7 +158,7 @@
 		user.visible_message("<span class='notice'>[user] refastens [src]'s maintenance panel!</span>", "<span class='notice'>You reset [src] to its factory settings!</span>")
 		emagged = FALSE
 		radiation_count = 0
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return TRUE
 	else
 		return ..()
@@ -171,7 +171,7 @@
 		return
 	radiation_count = 0
 	to_chat(user, "<span class='notice'>You flush [src]'s radiation counts, resetting it to normal.</span>")
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/geiger_counter/emag_act(mob/user)
 	if(emagged)

code/game/objects/items/devices/lightreplacer.dm

@@ -147,14 +147,23 @@
 
 /obj/item/lightreplacer/emag_act(user as mob)
 	if(!emagged)
-		Emag()
+		emagged = !emagged
+		playsound(loc, "sparks", 100, TRUE, SHORT_RANGE_SOUND_EXTRARANGE)
+		update_appearance(UPDATE_NAME|UPDATE_ICON_STATE)
 
 /obj/item/lightreplacer/attack_self(mob/user)
 	for(var/obj/machinery/light/target in user.loc)
 		ReplaceLight(target, user)
 	to_chat(user, status_string())
 
-/obj/item/lightreplacer/update_icon()
+/obj/item/lightreplacer/update_name()
+	. = ..()
+	if(emagged)
+		name = "shortcircuited [initial(name)]"
+	else
+		name = initial(name)
+
+/obj/item/lightreplacer/update_icon_state()
 	icon_state = "lightreplacer[emagged]"
 
 /obj/item/lightreplacer/proc/status_string()
@@ -214,15 +223,6 @@
 		to_chat(U, "<span class='warning'>There is a working [target.fitting] already inserted!</span>")
 		return
 
-/obj/item/lightreplacer/proc/Emag()
-	emagged = !emagged
-	playsound(loc, "sparks", 100, TRUE, SHORT_RANGE_SOUND_EXTRARANGE)
-	if(emagged)
-		name = "shortcircuited [initial(name)]"
-	else
-		name = initial(name)
-	update_icon()
-
 /obj/item/lightreplacer/proc/CanUse(mob/living/user)
 	add_fingerprint(user)
 	if(uses > 0)
@@ -249,9 +249,8 @@
 		to_chat(U, "[src]'s refill light blinks red.")
 
 /obj/item/lightreplacer/proc/janicart_insert(mob/user, obj/structure/janitorialcart/J)
-	J.put_in_cart(src, user)
 	J.myreplacer = src
-	J.update_icon()
+	J.put_in_cart(src, user)
 
 /obj/item/lightreplacer/cyborg/janicart_insert(mob/user, obj/structure/janitorialcart/J)
 	return

code/game/objects/items/devices/painter/airlock_painter.dm

@@ -58,5 +58,5 @@
 		A.icon = initial(airlock.icon)
 		A.overlays_file = initial(airlock.overlays_file)
 		A.assemblytype = initial(airlock.assemblytype)
-		A.update_icon()
+		A.update_appearance()
 		return TRUE

code/game/objects/items/devices/powersink.dm

@@ -30,7 +30,7 @@
 	attached = null
 	return ..()
 
-/obj/item/powersink/update_icon()
+/obj/item/powersink/update_icon_state()
 	icon_state = "powersink[mode == OPERATING]"
 
 /obj/item/powersink/proc/set_mode(value)
@@ -60,7 +60,7 @@
 			density = TRUE
 
 	mode = value
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	set_light(0)
 
 /obj/item/powersink/screwdriver_act(mob/user, obj/item/I)

code/game/objects/items/devices/radio/intercom.dm

@@ -61,10 +61,10 @@
 		if(direction)
 			setDir(direction)
 			set_pixel_offsets_from_dir(28, -28, 28, -28)
-		b_stat=1
+		b_stat = TRUE
 		on = FALSE
 	GLOB.global_intercoms.Add(src)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/radio/intercom/Initialize()
 	. = ..()
@@ -184,12 +184,12 @@
 		return
 	if(!I.use_tool(src, user, 10, volume = I.tool_volume) || buildstage != 2)
 		return
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	on = TRUE
-	b_stat = 0
+	b_stat = FALSE
 	buildstage = 3
 	to_chat(user, "<span class='notice'>You secure the electronics!</span>")
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	update_operating_status()
 	for(var/i, i<= 5, i++)
 		wires.on_cut(i, 1)
@@ -203,9 +203,9 @@
 	WIRECUTTER_SNIP_MESSAGE
 	new /obj/item/stack/cable_coil(get_turf(src),5)
 	on = FALSE
-	b_stat = 1
+	b_stat = TRUE
 	buildstage = 1
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	update_operating_status(FALSE)
 
 /obj/item/radio/intercom/welder_act(mob/user, obj/item/I)
@@ -220,11 +220,11 @@
 		new /obj/item/mounted/frame/intercom(get_turf(src))
 		qdel(src)
 
-/obj/item/radio/intercom/update_icon()
+/obj/item/radio/intercom/update_icon_state()
 	if(!circuitry_installed)
 		icon_state="intercom-frame"
-		return
-	icon_state = "intercom[!on?"-p":""][b_stat ? "-open":""]"
+	else
+		icon_state = "intercom[!on?"-p":""][b_stat ? "-open":""]"
 
 /obj/item/radio/intercom/proc/update_operating_status(on = TRUE)
 	var/area/current_area = get_area(src)
@@ -249,7 +249,7 @@
 		on = FALSE
 	else
 		on = current_area.powered(EQUIP) // set "on" to the equipment power status of our area.
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/intercom_electronics
 	name = "intercom electronics"

code/game/objects/items/devices/scanners.dm

@@ -596,6 +596,7 @@ REAGENT SCANNER
 	var/obj/item/stock_parts/cell/cell
 	var/cell_type = /obj/item/stock_parts/cell/upgraded
 	var/ready = TRUE // Ready to scan
+	var/printing = FALSE
 	var/time_to_use = 0 // How much time remaining before next scan is available.
 	var/usecharge = 750
 	var/scan_time = 10 SECONDS //how long does it take to scan
@@ -626,20 +627,22 @@ REAGENT SCANNER
 	playsound(src, 'sound/machines/defib_saftyon.ogg', 50, 0)
 	update_icon()
 
-/obj/item/bodyanalyzer/update_icon(printing = FALSE)
-	overlays.Cut()
-	var/percent = cell.percent()
+/obj/item/bodyanalyzer/update_icon_state()
+	if(!cell)
+		icon_state = "bodyanalyzer_0"
+		return
 	if(ready)
 		icon_state = "bodyanalyzer_1"
 	else
 		icon_state = "bodyanalyzer_2"
 
+/obj/item/bodyanalyzer/update_overlays()
+	. = ..()
+	var/percent = cell.percent()
 	var/overlayid = round(percent / 10)
-	overlayid = "bodyanalyzer_charge[overlayid]"
-	overlays += icon(icon, overlayid)
-
+	. += "bodyanalyzer_charge[overlayid]"
 	if(printing)
-		overlays += icon(icon, "bodyanalyzer_printing")
+		. += "bodyanalyzer_printing"
 
 /obj/item/bodyanalyzer/attack(mob/living/M, mob/living/carbon/human/user)
 	if(user.incapacitated() || !user.Adjacent(M))
@@ -686,14 +689,16 @@ REAGENT SCANNER
 			else
 				cell.use(usecharge)
 			ready = FALSE
-			update_icon(TRUE)
+			printing = TRUE
+			update_icon()
 			addtimer(CALLBACK(src, /obj/item/bodyanalyzer/.proc/setReady), scan_cd)
-			addtimer(CALLBACK(src, /obj/item/bodyanalyzer/.proc/update_icon), 20)
-
+			addtimer(VARSET_CALLBACK(src, printing, FALSE), 1.4 SECONDS)
+			addtimer(CALLBACK(src, /atom/.proc/update_icon, UPDATE_OVERLAYS), 1.5 SECONDS)
 	else if(iscorgi(M) && M.stat == DEAD)
 		to_chat(user, "<span class='notice'>You wonder if [M.p_they()] was a good dog. <b>[src] tells you they were the best...</b></span>") // :'(
 		playsound(loc, 'sound/machines/ping.ogg', 50, 0)
 		ready = FALSE
+		update_icon(UPDATE_ICON_STATE)
 		addtimer(CALLBACK(src, /obj/item/bodyanalyzer/.proc/setReady), scan_cd)
 		time_to_use = world.time + scan_cd
 	else

code/game/objects/items/devices/taperecorder.dm

@@ -26,7 +26,7 @@
 	..()
 	if(starts_with_tape)
 		mytape = new /obj/item/tape/random(src)
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 	soundloop = new(list(src))
 
 /obj/item/taperecorder/Destroy()
@@ -53,7 +53,7 @@
 			mytape = I
 			to_chat(user, "<span class='notice'>You insert [I] into [src].</span>")
 			playsound(src, 'sound/items/taperecorder/taperecorder_close.ogg', 50, FALSE)
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 
 /obj/item/taperecorder/proc/eject(mob/user)
 	if(mytape)
@@ -62,7 +62,7 @@
 		stop()
 		user.put_in_hands(mytape)
 		mytape = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/taperecorder/fire_act(datum/gas_mixture/air, exposed_temperature, exposed_volume, global_overlay = TRUE)
@@ -92,7 +92,7 @@
 	eject(usr)
 
 
-/obj/item/taperecorder/update_icon()
+/obj/item/taperecorder/update_icon_state()
 	if(!mytape)
 		icon_state = "taperecorder_empty"
 	else if(recording)
@@ -102,7 +102,6 @@
 	else
 		icon_state = "taperecorder_idle"
 
-
 /obj/item/taperecorder/hear_talk(mob/living/M as mob, list/message_pieces)
 	var/msg = multilingual_to_message(message_pieces)
 	if(mytape && recording)
@@ -146,7 +145,7 @@
 		recording = TRUE
 		atom_say("Recording started.")
 		update_sound()
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		mytape.timestamp += mytape.used_capacity
 		mytape.storedinfo += "\[[time2text(mytape.used_capacity * 10,"mm:ss")]\] Recording started."
 		var/used = mytape.used_capacity	//to stop runtimes when you eject the tape
@@ -180,7 +179,7 @@
 		playsound(src, 'sound/items/taperecorder/taperecorder_stop.ogg', 50, FALSE)
 		atom_say("Playback stopped.")
 		playing = FALSE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	update_sound()
 
 
@@ -198,7 +197,7 @@
 		return
 
 	playing = TRUE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	update_sound()
 	atom_say("Playback started.")
 	playsound(src, 'sound/items/taperecorder/taperecorder_play.ogg', 50, FALSE)
@@ -285,7 +284,7 @@
 	var/used_capacity = 0
 	var/list/storedinfo = list()
 	var/list/timestamp = list()
-	var/ruined = 0
+	var/ruined = FALSE
 
 /obj/item/tape/fire_act(datum/gas_mixture/air, exposed_temperature, exposed_volume, global_overlay = TRUE)
 	..()
@@ -308,22 +307,23 @@
 	to_chat(usr, "<span class='notice'>You erase the data from [src].</span>")
 	clear()
 
+/obj/item/tape/update_overlays()
+	. = ..()
+	if(ruined)
+		. += "ribbonoverlay"
+
 /obj/item/tape/proc/clear()
 	used_capacity = 0
 	storedinfo.Cut()
 	timestamp.Cut()
 
 /obj/item/tape/proc/ruin()
-	if(!ruined)
-		overlays += "ribbonoverlay"
-	ruined = 1
-
-
+	ruined = TRUE
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/tape/proc/fix()
-	overlays -= "ribbonoverlay"
-	ruined = 0
-
+	ruined = FALSE
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/tape/attackby(obj/item/I, mob/user)
 	if(ruined && istype(I, /obj/item/screwdriver))

code/game/objects/items/devices/transfer_valve.dm

@@ -152,23 +152,25 @@
 		spawn(50) // To stop a signal being spammed from a proxy sensor constantly going off or whatever
 			toggle = TRUE
 
-/obj/item/transfer_valve/update_icon()
-	overlays.Cut()
-	underlays = null
-
+/obj/item/transfer_valve/update_icon_state()
 	if(!tank_one && !tank_two && !attached_device)
 		icon_state = "valve_1"
+	else
+		icon_state = "valve"
+	
+/obj/item/transfer_valve/update_overlays()
+	. = ..()
+	underlays.Cut()
+	if(!tank_one && !tank_two && !attached_device)
 		return
-	icon_state = "valve"
-
 	if(tank_one)
-		overlays += "[tank_one.icon_state]"
+		. += "[tank_one.icon_state]"
 	if(tank_two)
 		var/icon/J = new(icon, icon_state = "[tank_two.icon_state]")
 		J.Shift(WEST, 13)
 		underlays += J
 	if(attached_device)
-		overlays += "device"
+		. += "device"
 
 /obj/item/transfer_valve/proc/merge_gases()
 	tank_two.air_contents.volume += tank_one.air_contents.volume

code/game/objects/items/flag.dm

@@ -8,6 +8,7 @@
 	w_class = WEIGHT_CLASS_BULKY
 	max_integrity = 40
 	resistance_flags = FLAMMABLE
+	custom_fire_overlay = "fire"
 	var/rolled = FALSE
 
 /obj/item/flag/attackby(obj/item/W, mob/user, params)
@@ -29,18 +30,16 @@
 	..()
 	update_icon()
 
-/obj/item/flag/update_icon()
-	overlays.Cut()
+/obj/item/flag/update_icon_state()
 	updateFlagIcon()
 	item_state = icon_state
 	if(rolled)
 		icon_state = "[icon_state]_rolled"
+		custom_fire_overlay = "fire_rolled"
+	else
+		custom_fire_overlay = initial(custom_fire_overlay)
 	if(resistance_flags & ON_FIRE)
 		item_state = "[item_state]_fire"
-	if((resistance_flags & ON_FIRE) && rolled)
-		overlays += image('icons/obj/flag.dmi', src , "fire_rolled")
-	else if((resistance_flags & ON_FIRE) && !rolled)
-		overlays += image('icons/obj/flag.dmi', src , "fire")
 	if(ismob(loc))
 		var/mob/M = loc
 		M.update_inv_r_hand()

code/game/objects/items/his_grace.dm

@@ -41,16 +41,18 @@
 	GLOB.poi_list -= src
 	return ..()
 
-/obj/item/his_grace/update_icon()
+/obj/item/his_grace/update_icon_state()
 	icon_state = ascended ? "gold" : "green"
 	item_state = ascended ? "toolbox_gold" : "artistic_toolbox"
-	cut_overlays()
+
+/obj/item/his_grace/update_overlays()
+	. = ..()
 	if(ascended)
-		add_overlay("triple_latch")
+		. += "triple_latch"
 	else if(awakened)
-		add_overlay("single_latch_open")
+		. += "single_latch_open"
 	else
-		add_overlay("single_latch")
+		. += "single_latch"
 
 /obj/item/his_grace/attack_self(mob/living/user)
 	if(!awakened)

code/game/objects/items/robot/robot_parts.dm

@@ -102,7 +102,7 @@
 
 /obj/item/robot_parts/robot_suit/New()
 	..()
-	updateicon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/robot_parts/robot_suit/Destroy()
 	QDEL_NULL(l_arm)
@@ -117,20 +117,20 @@
 /obj/item/robot_parts/robot_suit/attack_self(mob/user)
 	return
 
-/obj/item/robot_parts/robot_suit/proc/updateicon()
-	overlays.Cut()
+/obj/item/robot_parts/robot_suit/update_overlays()
+	. = ..()
 	if(l_arm)
-		overlays += "l_arm+o"
+		. += "l_arm+o"
 	if(r_arm)
-		overlays += "r_arm+o"
+		. += "r_arm+o"
 	if(chest)
-		overlays += "chest+o"
+		. += "chest+o"
 	if(l_leg)
-		overlays += "l_leg+o"
+		. += "l_leg+o"
 	if(r_leg)
-		overlays += "r_leg+o"
+		. += "r_leg+o"
 	if(head)
-		overlays += "head+o"
+		. += "head+o"
 
 /obj/item/robot_parts/robot_suit/proc/check_completion()
 	if(l_arm && r_arm)
@@ -158,7 +158,7 @@
 		user.drop_item()
 		W.forceMove(src)
 		l_leg = W
-		updateicon()
+		update_icon(UPDATE_OVERLAYS)
 
 	if(istype(W, /obj/item/robot_parts/r_leg))
 		if(r_leg)
@@ -166,7 +166,7 @@
 		user.drop_item()
 		W.forceMove(src)
 		r_leg = W
-		updateicon()
+		update_icon(UPDATE_OVERLAYS)
 
 	if(istype(W, /obj/item/robot_parts/l_arm))
 		if(l_arm)
@@ -174,7 +174,7 @@
 		user.drop_item()
 		W.forceMove(src)
 		l_arm = W
-		updateicon()
+		update_icon(UPDATE_OVERLAYS)
 
 	if(istype(W, /obj/item/robot_parts/r_arm))
 		if(r_arm)
@@ -182,7 +182,7 @@
 		user.drop_item()
 		W.forceMove(src)
 		r_arm = W
-		updateicon()
+		update_icon(UPDATE_OVERLAYS)
 
 	if(istype(W, /obj/item/robot_parts/chest))
 		var/obj/item/robot_parts/chest/CH = W
@@ -192,7 +192,7 @@
 			user.drop_item()
 			W.forceMove(src)
 			chest = W
-			updateicon()
+			update_icon(UPDATE_OVERLAYS)
 		else if(!CH.wired)
 			to_chat(user, "<span class='notice'>You need to attach wires to it first!</span>")
 		else
@@ -206,7 +206,7 @@
 			user.drop_item()
 			W.forceMove(src)
 			head = W
-			updateicon()
+			update_icon(UPDATE_OVERLAYS)
 		else
 			to_chat(user, "<span class='notice'>You need to attach a flash to it first!</span>")
 

code/game/objects/items/robot/robot_upgrades.dm

@@ -39,11 +39,11 @@
 /obj/item/borg/upgrade/proc/pre_install_checks(mob/living/silicon/robot/R)
 	if(R.stat == DEAD)
 		to_chat(usr, "<span class='warning'>[src] will not function on a deceased cyborg.</span>")
-		return FALSE
+		return
 	if(module_type && !istype(R.module, module_type))
 		to_chat(R, "<span class='warning'>Upgrade mounting error!  No suitable hardpoint detected!</span>")
 		to_chat(usr, "<span class='warning'>There's no mounting point for the module!</span>")
-		return FALSE
+		return
 	return TRUE
 
 /**
@@ -99,7 +99,7 @@
 /obj/item/borg/upgrade/rename/do_install(mob/living/silicon/robot/R)
 	if(!R.allow_rename)
 		to_chat(R, "<span class='warning'>Internal diagnostic error: incompatible upgrade module detected.</span>")
-		return 0
+		return
 	R.notify_ai(3, R.name, heldname)
 	R.name = heldname
 	R.custom_name = heldname
@@ -116,7 +116,7 @@
 /obj/item/borg/upgrade/restart/do_install(mob/living/silicon/robot/R)
 	if(R.health < 0)
 		to_chat(usr, "<span class='warning'>You have to repair the cyborg before using this module!</span>")
-		return 0
+		return
 
 	if(!R.key)
 		for(var/mob/dead/observer/ghost in GLOB.player_list)
@@ -286,7 +286,7 @@
 	var/obj/item/borg/upgrade/selfrepair/U = locate() in R
 	if(U)
 		to_chat(usr, "<span class='warning'>This unit is already equipped with a self-repair module.</span>")
-		return 0
+		return
 
 	cyborg = R
 	icon_state = "selfrepair_off"
@@ -308,9 +308,9 @@
 	else
 		to_chat(cyborg, "<span class='notice'>You deactivate the self-repair module.</span>")
 		STOP_PROCESSING(SSobj, src)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
-/obj/item/borg/upgrade/selfrepair/update_icon()
+/obj/item/borg/upgrade/selfrepair/update_icon_state()
 	if(cyborg)
 		icon_state = "selfrepair_[on ? "on" : "off"]"
 		for(var/X in actions)
@@ -322,7 +322,7 @@
 /obj/item/borg/upgrade/selfrepair/proc/deactivate()
 	STOP_PROCESSING(SSobj, src)
 	on = FALSE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/borg/upgrade/selfrepair/process()
 	if(!repair_tick)

code/game/objects/items/stacks/rods.dm

@@ -43,7 +43,7 @@ GLOBAL_LIST_INIT(rod_recipes, list ( \
 	is_cyborg = TRUE
 	materials = list()
 
-/obj/item/stack/rods/cyborg/update_icon()
+/obj/item/stack/rods/cyborg/update_icon_state()
 	return // icon_state should always be a full stack of rods.
 
 /obj/item/stack/rods/ten
@@ -58,9 +58,9 @@ GLOBAL_LIST_INIT(rod_recipes, list ( \
 /obj/item/stack/rods/New(loc, amount=null)
 	..()
 	recipes = GLOB.rod_recipes
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
-/obj/item/stack/rods/update_icon()
+/obj/item/stack/rods/update_icon_state()
 	var/amount = get_amount()
 	if((amount <= 5) && (amount > 0))
 		icon_state = "rods-[amount]"

code/game/objects/items/stacks/sheets/leather.dm

@@ -199,11 +199,7 @@ GLOBAL_LIST_INIT(sinew_recipes, list ( \
 			D.armor = D.armor.setRating(bullet_value = min(D.armor.getRating(BULLET) + 5, 50))
 			D.armor = D.armor.setRating(laser_value = min(D.armor.getRating(LASER) + 5, 50))
 			to_chat(user, "<span class='info'>You strengthen [target], improving its resistance against melee attacks.</span>")
-			D.update_icon()
-			if(D.hides == 3)
-				D.desc = "Autonomous Power Loader Unit. It's wearing a fearsome carapace entirely composed of goliath hide plates - its pilot must be an experienced monster hunter."
-			else
-				D.desc = "Autonomous Power Loader Unit. Its armour is enhanced with some goliath hide plates."
+			D.update_appearance(UPDATE_DESC|UPDATE_OVERLAYS)
 			use(1)
 		else
 			to_chat(user, "<span class='warning'>You can't improve [D] any further!</span>")

code/game/objects/items/tools/welder.dm

@@ -170,15 +170,7 @@
 	else
 		to_chat(user, "<span class='warning'>There's not enough fuel in [A] to refuel [src]!</span>")
 
-/obj/item/weldingtool/proc/update_torch()
-	overlays.Cut()
-	if(tool_enabled)
-		overlays += "[initial(icon_state)]-on"
-		item_state = "[initial(item_state)]1"
-	else
-		item_state = "[initial(item_state)]"
-
-/obj/item/weldingtool/update_icon()
+/obj/item/weldingtool/update_icon_state()
 	if(low_fuel_changes_icon)
 		var/ratio = GET_FUEL / maximum_fuel
 		ratio = CEILING(ratio*4, 1) * 25
@@ -186,8 +178,15 @@
 			icon_state = initial(icon_state)
 		else
 			icon_state = "[initial(icon_state)][ratio]"
-	update_torch()
-	..()
+	if(tool_enabled)
+		item_state = "[initial(item_state)]1"
+	else
+		item_state = "[initial(item_state)]"
+
+/obj/item/weldingtool/update_overlays()
+	. = ..()
+	if(tool_enabled)
+		. += "[initial(icon_state)]-on"
 
 /obj/item/weldingtool/cyborg_recharge(coeff, emagged)
 	if(reagents.check_and_add("fuel", maximum_fuel, 2 * coeff))

code/game/objects/items/toys.dm

@@ -96,7 +96,7 @@
 				qdel(src)
 	return
 
-/obj/item/toy/balloon/update_icon()
+/obj/item/toy/balloon/update_icon_state()
 	if(src.reagents.total_volume >= 1)
 		icon_state = "waterballoon"
 		item_state = "waterballoon"
@@ -772,21 +772,20 @@
 
 /obj/item/toy/windup_toolbox/Initialize(mapload)
 	. = ..()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/item/toy/windup_toolbox/update_icon()
-	..()
-	cut_overlays()
+/obj/item/toy/windup_toolbox/update_overlays()
+	. = ..()
 	if(active)
-		add_overlay("single_latch_open")
+		. += "single_latch_open"
 	else
-		add_overlay("single_latch")
+		. += "single_latch"
 
 /obj/item/toy/windup_toolbox/attack_self(mob/user)
 	if(!active)
 		to_chat(user, "<span class='notice'>You wind up [src], it begins to rumble.</span>")
 		active = TRUE
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 		playsound(src, 'sound/effects/pope_entry.ogg', 100)
 		animate_rumble(src)
 		addtimer(CALLBACK(src, .proc/stopRumble), 60 SECONDS)
@@ -795,7 +794,7 @@
 
 /obj/item/toy/windup_toolbox/proc/stopRumble()
 	active = FALSE
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	visible_message("<span class='warning'>[src] slowly stops rattling and falls still, its latch snapping shut.</span>") //subtle difference
 	playsound(loc, 'sound/weapons/batonextend.ogg', 100, TRUE)
 	animate(src, transform = matrix())
@@ -1113,7 +1112,7 @@
 	wieldsound = 'sound/weapons/chainsawstart.ogg'
 	attack_verb = list("sawed", "cut", "hacked", "carved", "cleaved", "butchered", "felled", "timbered")
 
-/obj/item/twohanded/toy/chainsaw/update_icon()
+/obj/item/twohanded/toy/chainsaw/update_icon_state()
 	if(wielded)
 		icon_state = "chainsaw[wielded]"
 	else

code/game/objects/items/weapons/RCL.dm

@@ -34,7 +34,7 @@
 				loaded.amount = amount
 			else
 				return
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		to_chat(user, "<span class='notice'>You add the cables to [src]. It now contains [loaded.amount].</span>")
 	else
 		..()
@@ -58,7 +58,7 @@
 	loaded.forceMove(user.loc)
 	user.put_in_hands(loaded)
 	loaded = null
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/twohanded/rcl/examine(mob/user)
 	. = ..()
@@ -71,7 +71,7 @@
 	active = FALSE
 	return ..()
 
-/obj/item/twohanded/rcl/update_icon()
+/obj/item/twohanded/rcl/update_icon_state()
 	if(!loaded)
 		icon_state = "rcl-0"
 		item_state = "rcl-0"
@@ -89,10 +89,9 @@
 		else
 			icon_state = "rcl-0"
 			item_state = "rcl-0"
-	..()
 
 /obj/item/twohanded/rcl/proc/is_empty(mob/user, loud = 1)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	if(!loaded || !loaded.amount)
 		if(loud)
 			to_chat(user, "<span class='notice'>The last of the cables unreel from [src].</span>")
@@ -151,4 +150,4 @@
 	loaded = new()
 	loaded.max_amount = max_amount
 	loaded.amount = max_amount
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)

code/game/objects/items/weapons/cash.dm

@@ -16,10 +16,9 @@
 
 /obj/item/stack/spacecash/New(loc, amt = null)
 	..()
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
-/obj/item/stack/spacecash/update_icon()
-	..()
+/obj/item/stack/spacecash/update_icon_state()
 	name = "[amount == max_amount ? "1000000" : amount] Credit[amount > 1 ? "s" : ""]"
 	if(amount >= 1 && amount < 10)
 		icon_state = "cashgreen"

code/game/objects/items/weapons/chrono_eraser.dm

@@ -63,8 +63,8 @@
 		TED = new(src.loc)
 		qdel(src)
 
-/obj/item/gun/energy/chrono_gun/update_icon()
-	return
+/obj/item/gun/energy/chrono_gun/update_overlays()
+	return list()
 
 /obj/item/gun/energy/chrono_gun/process_fire(atom/target as mob|obj|turf, mob/living/user as mob|obj, message = 1, params, zone_override, bonus_spread = 0)
 	if(field)
@@ -177,7 +177,7 @@
 			cached_icon.Insert(mob_icon, "frame[i]")
 
 		mob_underlay = mutable_appearance(cached_icon, "frame1")
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 		desc = initial(desc) + "<br><span class='info'>It appears to contain [target.name].</span>"
 	START_PROCESSING(SSobj, src)
@@ -188,7 +188,7 @@
 		gun.field_disconnect(src)
 	return ..()
 
-/obj/structure/chrono_field/update_icon()
+/obj/structure/chrono_field/update_icon_state()
 	var/ttk_frame = 1 - (tickstokill / initial(tickstokill))
 	ttk_frame = clamp(CEILING(ttk_frame * CHRONO_FRAME_COUNT, 1), 1, CHRONO_FRAME_COUNT)
 	if(ttk_frame != RPpos)
@@ -217,7 +217,7 @@
 			captured.Paralyse(8 SECONDS)
 			if(captured.loc != src)
 				captured.forceMove(src)
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 			if(gun)
 				if(gun.field_check(src))
 					tickstokill--

code/game/objects/items/weapons/defib.dm

@@ -33,17 +33,16 @@
 /obj/item/defibrillator/Initialize(mapload) //starts without a cell for rnd
 	. = ..()
 	paddles = new paddle_type(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/loaded/Initialize(mapload) //starts with hicap
 	. = ..()
 	cell = new(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/item/defibrillator/update_icon()
+/obj/item/defibrillator/update_icon(updates=ALL)
 	update_power()
-	update_overlays()
-	update_charge()
+	..()
 
 /obj/item/defibrillator/examine(mob/user)
 	. = ..()
@@ -58,28 +57,25 @@
 	else
 		powered = FALSE
 
-/obj/item/defibrillator/proc/update_overlays()
-	overlays.Cut()
+/obj/item/defibrillator/update_overlays()
+	. = ..()
 	if(paddles_on_defib)
-		overlays += "[icon_state]-paddles"
-	if(powered)
-		overlays += "[icon_state]-powered"
-	if(!cell)
-		overlays += "[icon_state]-nocell"
+		. += "[icon_state]-paddles"
 	if(!safety)
-		overlays += "[icon_state]-emagged"
-
-/obj/item/defibrillator/proc/update_charge()
-	if(powered) //so it doesn't show charge if it's unpowered
-		if(cell)
-			var/ratio = cell.charge / cell.maxcharge
-			ratio = CEILING(ratio*4, 1) * 25
-			overlays += "[icon_state]-charge[ratio]"
+		. += "[icon_state]-emagged"
+	if(powered)
+		. += "[icon_state]-powered"
+	if(powered && cell) 
+		var/ratio = cell.charge / cell.maxcharge
+		ratio = CEILING(ratio*4, 1) * 25
+		. += "[icon_state]-charge[ratio]"
+	if(!cell)
+		. += "[icon_state]-nocell"
 
 /obj/item/defibrillator/CheckParts(list/parts_list)
 	..()
 	cell = locate(/obj/item/stock_parts/cell) in contents
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/ui_action_click()
 	toggle_paddles()
@@ -109,7 +105,7 @@
 			cell = null
 			to_chat(user, "<span class='notice'>You remove the cell from [src].</span>")
 
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	return
 
 /obj/item/defibrillator/emag_act(user as mob)
@@ -131,7 +127,7 @@
 		safety = TRUE
 		visible_message("<span class='notice'>[src] beeps: Safety protocols enabled!</span>")
 		playsound(get_turf(src), 'sound/machines/defib_saftyon.ogg', 50, 0)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	..()
 
 /obj/item/defibrillator/verb/toggle_paddles()
@@ -146,7 +142,7 @@
 
 		if(!usr.put_in_hands(paddles))
 			to_chat(user, "<span class='warning'>You need a free hand to hold the paddles!</span>")
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 			return
 		paddles.loc = user
 		paddles_on_defib = FALSE
@@ -154,7 +150,7 @@
 		//Remove from their hands and back onto the defib unit
 		remove_paddles(user)
 
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	for(var/X in actions)
 		var/datum/action/A = X
 		A.UpdateButtonIcon()
@@ -163,7 +159,7 @@
 	..()
 	if(slot != slot_back)
 		remove_paddles(user)
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/item_action_slot_check(slot, mob/user)
 	if(slot == slot_back)
@@ -174,7 +170,7 @@
 	if(paddles in get_both_hands(M))
 		M.unEquip(paddles)
 		paddles_on_defib = TRUE
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	return
 
 /obj/item/defibrillator/Destroy()
@@ -189,12 +185,12 @@
 	if(cell)
 		if(cell.charge < (paddles.revivecost+chrgdeductamt))
 			powered = FALSE
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 		if(cell.use(chrgdeductamt))
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 			return TRUE
 		else
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 			return FALSE
 
 /obj/item/defibrillator/proc/cooldowncheck(mob/user)
@@ -207,8 +203,8 @@
 				user.visible_message("<span class='notice'>[src] beeps: Charge depleted.</span>")
 				playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 		paddles.cooldown = FALSE
-		paddles.update_icon()
-		update_icon()
+		paddles.update_icon(UPDATE_ICON_STATE)
+		update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/compact
 	name = "compact defibrillator"
@@ -223,7 +219,7 @@
 /obj/item/defibrillator/compact/loaded/Initialize(mapload)
 	. = ..()
 	cell = new(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/compact/item_action_slot_check(slot, mob/user)
 	if(slot == slot_belt)
@@ -242,7 +238,7 @@
 /obj/item/defibrillator/compact/combat/loaded/Initialize(mapload)
 	. = ..()
 	cell = new(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/compact/advanced
 	name = "advanced compact defibrillator"
@@ -260,12 +256,12 @@
 	if(W == paddles)
 		paddles.unwield()
 		toggle_paddles()
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/compact/advanced/loaded/Initialize(mapload)
 	. = ..()
 	cell = new /obj/item/stock_parts/cell/bluespace/charging(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/defibrillator/compact/advanced/emp_act(severity)
 	if(world.time > next_emp_message)
@@ -277,7 +273,7 @@
 	if(W == paddles)
 		paddles.unwield()
 		toggle_paddles()
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 		return
 
 //paddles
@@ -306,10 +302,10 @@
 		defib = mainunit
 		loc = defib
 		busy = FALSE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 	return
 
-/obj/item/twohanded/shockpaddles/update_icon()
+/obj/item/twohanded/shockpaddles/update_icon_state()
 	icon_state = "[base_icon_state][wielded]"
 	item_state = "[base_icon_state][wielded]"
 	if(cooldown)
@@ -330,8 +326,8 @@
 		to_chat(user, "<span class='notice'>The paddles snap back into the main unit.</span>")
 		defib.paddles_on_defib = TRUE
 		loc = defib
-		defib.update_icon()
-		update_icon()
+		defib.update_icon(UPDATE_OVERLAYS)
+		update_icon(UPDATE_ICON_STATE)
 	unwield(user)
 
 /obj/item/twohanded/shockpaddles/on_mob_move(dir, mob/user)
@@ -384,12 +380,12 @@
 			defib.deductcharge(revivecost)
 			cooldown = TRUE
 			busy = FALSE
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 			defib.cooldowncheck(user)
 			return
 		user.visible_message("<span class='warning'>[user] begins to place [src] on [M.name]'s chest.</span>", "<span class='warning'>You begin to place [src] on [M.name]'s chest.</span>")
 		busy = TRUE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		var/mob/dead/observer/ghost = H.get_ghost(TRUE)
 		if(ghost && ghost.can_reenter_corpse)
 			to_chat(ghost, "<span class='ghostalert'>Your heart is being defibrillated. Return to your body if you want to be revived!</span> (Verbs -> Ghost -> Re-enter corpse)")
@@ -415,14 +411,14 @@
 							user.visible_message("<span class='notice'>[defib] buzzes: Patient's chest is obscured. Operation aborted.</span>")
 							playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 							busy = FALSE
-							update_icon()
+							update_icon(UPDATE_ICON_STATE)
 							return
 				if(H.undergoing_cardiac_arrest())
 					if(!H.get_int_organ(/obj/item/organ/internal/heart) && !H.get_int_organ(/obj/item/organ/internal/brain/slime)) //prevents defibing someone still alive suffering from a heart attack attack if they lack a heart
 						user.visible_message("<span class='boldnotice'>[defib] buzzes: Resuscitation failed - Failed to pick up any heart electrical activity.</span>")
 						playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 						busy = FALSE
-						update_icon()
+						update_icon(UPDATE_ICON_STATE)
 						return
 					else
 						var/obj/item/organ/internal/heart/heart = H.get_int_organ(/obj/item/organ/internal/heart)
@@ -430,7 +426,7 @@
 							user.visible_message("<span class='boldnotice'>[defib] buzzes: Resuscitation failed - Heart necrosis detected.</span>")
 							playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 							busy = FALSE
-							update_icon()
+							update_icon(UPDATE_ICON_STATE)
 							return
 						H.set_heartattack(FALSE)
 						SEND_SIGNAL(H, COMSIG_LIVING_MINOR_SHOCK, 100)
@@ -442,7 +438,7 @@
 						defib.deductcharge(revivecost)
 						busy = FALSE
 						cooldown = TRUE
-						update_icon()
+						update_icon(UPDATE_ICON_STATE)
 						defib.cooldowncheck(user)
 						return
 				if(H.stat == DEAD)
@@ -497,14 +493,14 @@
 							user.visible_message("<span class='boldnotice'>[defib] buzzes: Resuscitation failed.</span>")
 						playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 						defib.deductcharge(revivecost)
-					update_icon()
 					cooldown = TRUE
+					update_icon(UPDATE_ICON_STATE)
 					defib.cooldowncheck(user)
 				else
 					user.visible_message("<span class='notice'>[defib] buzzes: Patient is not in a valid state. Operation aborted.</span>")
 					playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 		busy = FALSE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/item/borg_defib
 	name = "defibrillator paddles"
@@ -551,10 +547,10 @@
 				R.cell.use(revivecost)
 			cooldown = TRUE
 			busy = FALSE
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 			spawn(50)
 				cooldown = FALSE
-				update_icon()
+				update_icon(UPDATE_ICON_STATE)
 			return
 		user.visible_message("<span class='warning'>[user] begins to place [src] on [M.name]'s chest.</span>", "<span class='warning'>You begin to place [src] on [M.name]'s chest.</span>")
 		busy = TRUE
@@ -619,16 +615,16 @@
 						if(isrobot(user))
 							var/mob/living/silicon/robot/R = user
 							R.cell.use(revivecost)
-					update_icon()
 					cooldown = TRUE
+					update_icon(UPDATE_ICON_STATE)
 					spawn(50)
 						cooldown = FALSE
-						update_icon()
+						update_icon(UPDATE_ICON_STATE)
 				else
 					user.visible_message("<span class='notice'>[user] buzzes: Patient is not in a valid state. Operation aborted.</span>")
 					playsound(get_turf(src), 'sound/machines/defib_failed.ogg', 50, 0)
 		busy = FALSE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/item/twohanded/shockpaddles/syndicate
 	name = "combat defibrillator paddles"

code/game/objects/items/weapons/dice.dm

@@ -304,8 +304,8 @@
 	icon_state = "d100"
 	sides = 100
 
-/obj/item/dice/d100/update_icon()
-	return
+/obj/item/dice/d100/update_overlays()
+	return list()
 
 /obj/item/dice/d20/e20
 	var/triggered = FALSE
@@ -333,7 +333,7 @@
 		comment = "NAT 20!"
 	else if(sides == 20 && result == 1)
 		comment = "Ouch, bad luck."
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	if(initial(icon_state) == "d00")
 		result = (result - 1) * 10
 	if(length(special_faces) == sides)
@@ -375,9 +375,9 @@
 	log_game("E20 detonated at [A.name] ([epicenter.x],[epicenter.y],[epicenter.z]) with a roll of [actual_result]. Triggered by: [key_name(user)]")
 	add_attack_logs(user, src, "detonated with a roll of [actual_result]", ATKLOG_FEW)
 
-/obj/item/dice/update_icon()
-	overlays.Cut()
-	overlays += "[icon_state][result]"
+/obj/item/dice/update_overlays()
+	. = ..()
+	. += "[icon_state][result]"
 
 /obj/item/storage/box/dice
 	name = "Box of dice"

code/game/objects/items/weapons/dnascrambler.dm

@@ -6,7 +6,7 @@
 	icon_state = "lepopen"
 	var/used = FALSE
 
-/obj/item/dnascrambler/update_icon()
+/obj/item/dnascrambler/update_icon_state()
 	if(used)
 		icon_state = "lepopen0"
 	else
@@ -52,5 +52,5 @@
 
 	add_attack_logs(user, target, "injected with [src]")
 	used = TRUE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	name = "used " + name

code/game/objects/items/weapons/explosives.dm

@@ -33,14 +33,14 @@
 		assemblyattacher = user.ckey
 		to_chat(user, "<span class='notice'>You add [A] to [src].</span>")
 		playsound(src, 'sound/weapons/tap.ogg', 20, 1)
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return
 	if(nadeassembly && istype(I, /obj/item/wirecutters))
 		playsound(src, I.usesound, 20, 1)
 		nadeassembly.loc = get_turf(src)
 		nadeassembly.master = null
 		nadeassembly = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return
 	..()
 
@@ -80,16 +80,16 @@
 	if(do_after(user, 50 * toolspeed, target = AM))
 		if(!user.unEquip(src))
 			return
-		src.target = AM
+		target = AM
 		loc = null
 
 		message_admins("[key_name_admin(user)]([ADMIN_QUE(user,"?")]) ([ADMIN_FLW(user,"FLW")]) planted [src.name] on [target.name] at ([target.x],[target.y],[target.z] - <A HREF='?_src_=holder;adminplayerobservecoodjump=1;X=[target.x];Y=[target.y];Z=[target.z]'>JMP</a>) with [det_time] second fuse",0,1)
 		log_game("[key_name(user)] planted [name] on [target.name] at ([target.x],[target.y],[target.z]) with [det_time] second fuse")
 
-		target.overlays += image_overlay
+		AddComponent(/datum/component/persistent_overlay, image_overlay, target)
 		if(!nadeassembly)
 			to_chat(user, "<span class='notice'>You plant the bomb. Timer counting down from [det_time].</span>")
-			addtimer(CALLBACK(src, .proc/prime), det_time*10)
+			addtimer(CALLBACK(src, .proc/prime), det_time SECONDS)
 
 /obj/item/grenade/plastic/suicide_act(mob/user)
 	message_admins("[key_name_admin(user)]([ADMIN_QUE(user,"?")]) ([ADMIN_FLW(user,"FLW")]) suicided with [src.name] at ([user.x],[user.y],[user.z] - <A HREF='?_src_=holder;adminplayerobservecoodjump=1;X=[user.x];Y=[user.y];Z=[user.z]'>JMP</a>)",0,1)
@@ -120,7 +120,7 @@
 	user.gib()
 	return OBLITERATION
 
-/obj/item/grenade/plastic/update_icon()
+/obj/item/grenade/plastic/update_icon_state()
 	if(nadeassembly)
 		icon_state = "[item_state]1"
 	else
@@ -153,7 +153,6 @@
 	if(target)
 		if(!QDELETED(target))
 			location = get_turf(target)
-			target.overlays -= image_overlay
 			if(!ex_breach && istype(target, /turf/simulated/wall)) //Walls get dismantled instead of destroyed to avoid making unwanted holes to space.
 				var/turf/simulated/wall/W = target
 				W.dismantle_wall(TRUE, TRUE)
@@ -219,7 +218,6 @@
 	if(target)
 		if(!QDELETED(target))
 			location = get_turf(target)
-			target.overlays -= image_overlay
 	else
 		location = get_turf(src)
 	if(location)

code/game/objects/items/weapons/flamethrower.dm

@@ -48,14 +48,8 @@
 		igniter.flamethrower_process(location)
 
 
-/obj/item/flamethrower/update_icon()
-	cut_overlays()
-	if(igniter)
-		add_overlay("+igniter[status]")
-	if(ptank)
-		add_overlay("+ptank")
+/obj/item/flamethrower/update_icon_state()
 	if(lit)
-		add_overlay("+lit")
 		item_state = "flamethrower_1"
 	else
 		item_state = "flamethrower_0"
@@ -64,6 +58,15 @@
 		M.update_inv_l_hand()
 		M.update_inv_r_hand()
 
+/obj/item/flamethrower/update_overlays()
+	. = ..()
+	if(igniter)
+		. += "+igniter[status]"
+	if(ptank)
+		. += "+ptank"
+	if(lit)
+		. += "+lit"
+
 /obj/item/flamethrower/can_enter_storage(obj/item/storage/S, mob/user)
 	if(lit)
 		to_chat(user, "<span class='warning'>[S] can't hold [src] while it's lit!</span>")

code/game/objects/items/weapons/garrote.dm

@@ -10,32 +10,24 @@
 	icon_state = "garrot_wrap"
 	w_class = WEIGHT_CLASS_TINY
 	var/mob/living/carbon/human/strangling
-	var/improvised = 0
+	var/improvised = FALSE
 	var/garrote_time
 
 /obj/item/twohanded/garrote/Destroy()
 	strangling = null
 	return ..()
 
-/obj/item/twohanded/garrote/update_icon()
+/obj/item/twohanded/garrote/update_icon_state()
 	if(strangling) // If we're strangling someone we want our icon to stay wielded
-		icon_state = "garrot_unwrap"
-		return
-
-	icon_state = "garrot_[wielded ? "un" : ""]wrap"
+		icon_state = "garrot_[improvised ? "I_" : ""]unwrap"
+	else
+		icon_state = "garrot_[improvised ? "I_" : ""][wielded ? "un" : ""]wrap"
 
 /obj/item/twohanded/garrote/improvised // Made via tablecrafting
 	name = "garrote"
 	desc = "A length of cable with a shoddily-carved wooden handle tied to either end.<br>You suspect you'd have to be behind the target to use this weapon effectively."
 	icon_state = "garrot_I_wrap"
-	improvised = 1
-
-/obj/item/twohanded/garrote/improvised/update_icon()
-	if(strangling)
-		icon_state = "garrot_I_unwrap"
-		return
-
-	icon_state = "garrot_I_[wielded ? "un" : ""]wrap"
+	improvised = TRUE
 
 /obj/item/twohanded/garrote/wield(mob/living/carbon/user)
 	if(strangling)
@@ -43,7 +35,7 @@
 				"<span class='warning'>You remove [src] from [strangling]'s neck.</span>")
 
 		strangling = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		STOP_PROCESSING(SSobj, src)
 
 	else
@@ -99,7 +91,7 @@
 	garrote_time = world.time + 10
 	START_PROCESSING(SSobj, src)
 	strangling = M
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 	playsound(src.loc, 'sound/weapons/cablecuff.ogg', 15, 1, -1)
 
@@ -112,14 +104,14 @@
 /obj/item/twohanded/garrote/process()
 	if(!strangling)
 		// Our mark got gibbed or similar
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		STOP_PROCESSING(SSobj, src)
 		return
 
 
 	if(!istype(loc, /mob/living/carbon/human))
 		strangling = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		STOP_PROCESSING(SSobj, src)
 		return
 
@@ -137,7 +129,7 @@
 				 "<span class='warning'>You lose your grip on [strangling]'s neck.</span>")
 
 		strangling = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		STOP_PROCESSING(SSobj, src)
 
 		return
@@ -147,7 +139,7 @@
 				"<span class='warning'>You lose your grip on [strangling]'s neck.</span>")
 
 		strangling = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		STOP_PROCESSING(SSobj, src)
 
 		return

code/game/objects/items/weapons/grenades/chem_grenade.dm

@@ -50,22 +50,10 @@
 		return O
 	return null
 
-
-/obj/item/grenade/chem_grenade/proc/update_overlays()
-	underlays = list()
-	if(nadeassembly)
-		underlays += "[nadeassembly.a_left.icon_state]_left"
-		for(var/O in nadeassembly.a_left.attached_overlays)
-			underlays += "[O]_l"
-		underlays += "[nadeassembly.a_right.icon_state]_right"
-		for(var/O in nadeassembly.a_right.attached_overlays)
-			underlays += "[O]_r"
-
-/obj/item/grenade/chem_grenade/update_icon()
+/obj/item/grenade/chem_grenade/update_icon_state()
 	if(nadeassembly)
 		icon = 'icons/obj/assemblies/new_assemblies.dmi'
 		icon_state = bomb_state
-		update_overlays()
 		var/obj/item/assembly/A = get_trigger()
 		if(stage != READY)
 			name = "bomb casing[label]"
@@ -90,6 +78,15 @@
 				else
 					icon_state += "_locked"
 				name = payload_name + "grenade" + label
+	
+	underlays.Cut()
+	if(nadeassembly)
+		underlays += "[nadeassembly.a_left.icon_state]_left"
+		for(var/O in nadeassembly.a_left.attached_overlays)
+			underlays += "[O]_l"
+		underlays += "[nadeassembly.a_right.icon_state]_right"
+		for(var/O in nadeassembly.a_right.attached_overlays)
+			underlays += "[O]_r"
 
 
 /obj/item/grenade/chem_grenade/attack_self(mob/user)
@@ -98,7 +95,7 @@
 		var/area/A = get_area(bombturf)
 		if(nadeassembly)
 			nadeassembly.attack_self(user)
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 		else if(clown_check(user))
 			// This used to go before the assembly check, but that has absolutely zero to do with priming the damn thing.  You could spam the admins with it.
 			log_game("[key_name(usr)] has primed a [name] for detonation at [A.name] ([bombturf.x],[bombturf.y],[bombturf.z]) [contained].")
@@ -133,7 +130,7 @@
 		else
 			if(label)
 				label = null
-				update_icon()
+				update_icon(UPDATE_ICON_STATE)
 				to_chat(user, "You remove the label from [src].")
 				return 1
 	if(istype(I, /obj/item/screwdriver))
@@ -142,7 +139,7 @@
 				to_chat(user, "<span class='notice'>You lock the assembly.</span>")
 				playsound(loc, prime_sound, 25, -3)
 				stage = READY
-				update_icon()
+				update_icon(UPDATE_ICON_STATE)
 				contained = ""
 				cores = "" // clear them out so no recursive logging by accidentally
 				for(var/obj/O in beakers)
@@ -195,7 +192,7 @@
 		assemblyattacher = user.ckey
 		stage = WIRED
 		to_chat(user, "<span class='notice'>You add [A] to [src]!</span>")
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 	else if(stage == EMPTY && istype(I, /obj/item/stack/cable_coil))
 		var/obj/item/stack/cable_coil/C = I
@@ -203,12 +200,12 @@
 
 		stage = WIRED
 		to_chat(user, "<span class='notice'>You rig [src].</span>")
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 	else if(stage == READY && istype(I, /obj/item/wirecutters))
 		to_chat(user, "<span class='notice'>You unlock the assembly.</span>")
 		stage = WIRED
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 	else if(stage == WIRED && istype(I, /obj/item/wrench))
 		to_chat(user, "<span class='notice'>You open the grenade and remove the contents.</span>")
@@ -223,7 +220,7 @@
 			for(var/obj/O in beakers)
 				O.forceMove(get_turf(src))
 			beakers = list()
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 
 //assembly stuff
@@ -286,7 +283,7 @@
 				O.forceMove(get_turf(src))
 			beakers = list()
 		stage = EMPTY
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return
 
 	if(nadeassembly)
@@ -448,7 +445,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/grenade/chem_grenade/firefighting
@@ -466,7 +463,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/grenade/chem_grenade/incendiary
 	payload_name = "incendiary"
@@ -485,7 +482,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/grenade/chem_grenade/antiweed
@@ -506,7 +503,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/grenade/chem_grenade/cleaner
@@ -526,7 +523,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/grenade/chem_grenade/teargas
@@ -546,7 +543,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/grenade/chem_grenade/facid
 	payload_name = "acid smoke"
@@ -566,7 +563,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/grenade/chem_grenade/saringas
 	payload_name = "sarin gas"
@@ -585,7 +582,7 @@
 
 	beakers += B1
 	beakers += B2
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 #undef EMPTY
 #undef WIRED

code/game/objects/items/weapons/implants/implant_mindshield.dm

@@ -42,8 +42,6 @@
 /obj/item/implanter/mindshield/New()
 	imp = new /obj/item/implant/mindshield(src)
 	..()
-	update_icon()
-
 
 /obj/item/implantcase/mindshield
 	name = "implant case - 'mindshield'"

code/game/objects/items/weapons/implants/implantcase.dm

@@ -12,18 +12,22 @@
 	materials = list(MAT_GLASS=500)
 	var/obj/item/implant/imp = null
 
-
-/obj/item/implantcase/update_icon()
+/obj/item/implantcase/proc/update_state()
 	if(imp)
-		icon_state = "implantcase-[imp.item_color]"
 		origin_tech = imp.origin_tech
 		flags = imp.flags & ~DROPDEL
 		reagents = imp.reagents
 	else
-		icon_state = "implantcase-0"
 		origin_tech = initial(origin_tech)
 		flags = initial(flags)
 		reagents = null
+	update_icon(UPDATE_ICON_STATE)
+
+/obj/item/implantcase/update_icon_state()
+	if(imp)
+		icon_state = "implantcase-[imp.item_color]"
+	else
+		icon_state = "implantcase-0"
 
 
 /obj/item/implantcase/attackby(obj/item/W, mob/user, params)
@@ -38,8 +42,8 @@
 			I.imp.loc = src
 			imp = I.imp
 			I.imp = null
-			update_icon()
-			I.update_icon()
+			update_state()
+			I.update_icon(UPDATE_ICON_STATE)
 		else
 			if(imp)
 				if(I.imp)
@@ -47,8 +51,8 @@
 				imp.loc = I
 				I.imp = imp
 				imp = null
-				update_icon()
-			I.update_icon()
+				update_state()
+			I.update_icon(UPDATE_ICON_STATE)
 
 	/*else if(istype(W, /obj/item/ammo_casing/shotgun/implanter))
 		var/obj/item/ammo_casing/shotgun/implanter/I = W
@@ -57,7 +61,7 @@
 
 /obj/item/implantcase/New()
 	..()
-	update_icon()
+	update_state()
 
 
 /obj/item/implantcase/tracking

code/game/objects/items/weapons/implants/implanter.dm

@@ -13,7 +13,7 @@
 	var/obj/item/implant/imp = null
 
 
-/obj/item/implanter/update_icon()
+/obj/item/implanter/update_icon_state()
 	if(imp)
 		icon_state = "implanter1"
 		origin_tech = imp.origin_tech
@@ -38,7 +38,7 @@
 					else
 						M.visible_message("[user] has implanted [M].", "<span class='notice'>[user] implants you.</span>")
 					imp = null
-					update_icon()
+					update_icon(UPDATE_ICON_STATE)
 
 /obj/item/implanter/attackby(obj/item/W, mob/user, params)
 	..()
@@ -48,7 +48,7 @@
 /obj/item/implanter/New()
 	..()
 	spawn(1)
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 
 /obj/item/implanter/adrenalin

code/game/objects/items/weapons/implants/implantpad.dm

@@ -14,12 +14,11 @@
 		dropcase()
 	return ..()
 
-/obj/item/implantpad/update_icon()
+/obj/item/implantpad/update_icon_state()
 	if(case)
-		src.icon_state = "implantpad-1"
+		icon_state = "implantpad-1"
 	else
-		src.icon_state = "implantpad-0"
-	return
+		icon_state = "implantpad-0"
 
 /obj/item/implantpad/proc/addcase(mob/user as mob, obj/item/implantcase/C as obj)
 	if(!user || !C)
@@ -30,7 +29,7 @@
 	user.unEquip(C)
 	C.forceMove(src)
 	case = C
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/implantpad/proc/dropcase(mob/user as mob)
 	if(!case)
@@ -41,12 +40,12 @@
 			add_fingerprint(user)
 			case.add_fingerprint(user)
 			case = null
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 			return
 
 	case.forceMove(get_turf(src))
 	case = null
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/implantpad/verb/remove_implant()
 	set category = "Object"

code/game/objects/items/weapons/legcuffs.dm

@@ -26,7 +26,7 @@
 /obj/item/restraints/legcuffs/beartrap/New()
 	..()
 
-/obj/item/restraints/legcuffs/beartrap/update_icon()
+/obj/item/restraints/legcuffs/beartrap/update_icon_state()
 	icon_state = "beartrap[armed]"
 
 /obj/item/restraints/legcuffs/beartrap/Destroy()
@@ -43,7 +43,7 @@
 	..()
 	if(ishuman(user) && !user.stat && !user.restrained())
 		armed = !armed
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		to_chat(user, "<span class='notice'>[src] is now [armed ? "armed" : "disarmed"]</span>")
 
 /obj/item/restraints/legcuffs/beartrap/attackby(obj/item/I, mob/user) //Let's get explosive.

code/game/objects/items/weapons/mop.dm

@@ -70,9 +70,8 @@
 		return ..()
 
 /obj/item/mop/proc/janicart_insert(mob/user, obj/structure/janitorialcart/J)
+	J.mymop = src
 	J.put_in_cart(src, user)
-	J.mymop=src
-	J.update_icon()
 
 /obj/item/mop/wash(mob/user, atom/source)
 	reagents.add_reagent("water", 5)

code/game/objects/items/weapons/paint.dm

@@ -14,6 +14,7 @@
 	possible_transfer_amounts = list(5,10,20,30,50,70)
 	volume = 70
 	container_type = OPENCONTAINER
+	blocks_emissive = EMISSIVE_BLOCK_GENERIC
 
 /obj/item/reagent_containers/glass/paint/afterattack(turf/simulated/target, mob/user, proximity)
 	if(!proximity)

code/game/objects/items/weapons/storage/bags.dm

@@ -45,7 +45,7 @@
 	playsound(loc, 'sound/items/eatfood.ogg', 50, 1, -1)
 	return TOXLOSS
 
-/obj/item/storage/bag/trash/update_icon()
+/obj/item/storage/bag/trash/update_icon_state()
 	switch(contents.len)
 		if(21 to INFINITY)
 			icon_state = "[initial(icon_state)]3"
@@ -59,14 +59,12 @@
 		var/mob/living/carbon/human/H = loc
 		H.update_inv_l_hand()
 		H.update_inv_r_hand()
-	..()
 
 /obj/item/storage/bag/trash/cyborg
 
 /obj/item/storage/bag/trash/proc/janicart_insert(mob/user, obj/structure/janitorialcart/J)
+	J.mybag = src
 	J.put_in_cart(src, user)
-	J.mybag=src
-	J.update_icon()
 
 /obj/item/storage/bag/trash/cyborg/janicart_insert(mob/user, obj/structure/janitorialcart/J)
 	return
@@ -405,58 +403,51 @@
 		if(prob(10))
 			M.Weaken(4 SECONDS)
 
-/obj/item/storage/bag/tray/proc/rebuild_overlays()
-	overlays.Cut()
+/obj/item/storage/bag/tray/update_icon_state()
+	return
+
+/obj/item/storage/bag/tray/update_overlays()
+	. = ..()
 	for(var/obj/item/I in contents)
-		overlays += image("icon" = I.icon, "icon_state" = I.icon_state, "layer" = -1)
-
-/obj/item/storage/bag/tray/remove_from_storage(obj/item/W as obj, atom/new_location)
-	..()
-	rebuild_overlays()
-
-/obj/item/storage/bag/tray/handle_item_insertion(obj/item/I, prevent_warning = 0)
-	overlays += image("icon" = I.icon, "icon_state" = I.icon_state, "layer" = -1)
-	..()
+		. += image(icon = I.icon, icon_state = I.icon_state, layer = -1)
 
 /obj/item/storage/bag/tray/cyborg
 
 /obj/item/storage/bag/tray/cyborg/afterattack(atom/target, mob/user as mob)
 	if( isturf(target) || istype(target,/obj/structure/table) )
-		var/foundtable = istype(target,/obj/structure/table/)
-		if( !foundtable ) //it must be a turf!
+		var/found_table = istype(target,/obj/structure/table/)
+		if(!found_table) //it must be a turf!
 			for(var/obj/structure/table/T in target)
-				foundtable = 1
+				found_table = TRUE
 				break
 
 		var/turf/dropspot
-		if( !foundtable ) // don't unload things onto walls or other silly places.
+		if(!found_table) // don't unload things onto walls or other silly places.
 			dropspot = user.loc
 		else if( isturf(target) ) // they clicked on a turf with a table in it
 			dropspot = target
 		else					// they clicked on a table
 			dropspot = target.loc
 
-		overlays = null
-
-		var/droppedSomething = 0
+		var/dropped_something = FALSE
 
 		for(var/obj/item/I in contents)
 			I.loc = dropspot
 			contents.Remove(I)
-			droppedSomething = 1
-			if(!foundtable && isturf(dropspot))
+			dropped_something = TRUE
+			if(!found_table && isturf(dropspot))
 				// if no table, presume that the person just shittily dropped the tray on the ground and made a mess everywhere!
 				spawn()
 					for(var/i = 1, i <= rand(1,2), i++)
 						if(I)
 							step(I, pick(NORTH,SOUTH,EAST,WEST))
 							sleep(rand(2,4))
-		if( droppedSomething )
-			if( foundtable )
+		if(dropped_something)
+			if(found_table)
 				user.visible_message("<span class='notice'>[user] unloads [user.p_their()] service tray.</span>")
 			else
 				user.visible_message("<span class='notice'>[user] drops all the items on [user.p_their()] tray.</span>")
-
+		update_icon(UPDATE_OVERLAYS)
 	return ..()
 
 
@@ -466,8 +457,8 @@
 /obj/item/storage/bag/tray/cookies_tray/populate_contents() // By Azule Utama, thank you a lot!
 	for(var/i in 1 to 6)
 		var/obj/item/C = new cookie(src)
-		handle_item_insertion(C)    // Done this way so the tray actually has the cookies visible when spawned
-	rebuild_overlays()
+		C.in_inventory = TRUE
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/storage/bag/tray/cookies_tray/sugarcookie
 	cookie = /obj/item/reagent_containers/food/snacks/sugarcookie

code/game/objects/items/weapons/storage/belt.dm

@@ -13,14 +13,13 @@
 	/// Do we have overlays for items held inside the belt?
 	var/use_item_overlays = FALSE
 
-/obj/item/storage/belt/update_icon()
+/obj/item/storage/belt/update_overlays()
+	. = ..()
 	if(use_item_overlays)
-		cut_overlays()
 		for(var/obj/item/I in contents)
 			var/image/belt_image = image(icon, I.belt_icon)
 			belt_image.color = I.color
-			add_overlay(belt_image)
-	..()
+			. += belt_image
 
 /obj/item/storage/belt/proc/can_use()
 	return is_equipped()
@@ -433,8 +432,7 @@
 	. = ..()
 	update_icon()
 
-/obj/item/storage/belt/lazarus/update_icon()
-	..()
+/obj/item/storage/belt/lazarus/update_icon_state()
 	icon_state = "[initial(icon_state)]_[length(contents)]"
 
 /obj/item/storage/belt/lazarus/attackby(obj/item/I, mob/user)
@@ -465,8 +463,7 @@
 	for(var/I in 1 to 8)
 		new /obj/item/ammo_casing/shotgun/beanbag(src)
 
-/obj/item/storage/belt/bandolier/update_icon()
-	..()
+/obj/item/storage/belt/bandolier/update_icon_state()
 	icon_state = "[initial(icon_state)]_[length(contents)]"
 
 /obj/item/storage/belt/bandolier/attackby(obj/item/I, mob/user)
@@ -611,13 +608,13 @@
 		return
 	playsound(src, 'sound/weapons/blade_unsheath.ogg', 20)
 
-/obj/item/storage/belt/rapier/update_icon()
-	. = ..()
-	icon_state = initial(icon_state)
-	item_state = initial(item_state)
+/obj/item/storage/belt/rapier/update_icon_state()
 	if(length(contents))
 		icon_state = "[icon_state]-rapier"
 		item_state = "[item_state]-rapier"
+	else
+		icon_state = initial(icon_state)
+		item_state = initial(item_state)
 	if(isliving(loc))
 		var/mob/living/L = loc
 		L.update_inv_belt()

code/game/objects/items/weapons/storage/boxes.dm

@@ -724,10 +724,26 @@
 	foldable = null
 	var/design = NODESIGN
 
-/obj/item/storage/box/papersack/update_icon()
-	if(!contents.len)
+/obj/item/storage/box/papersack/update_desc()
+	. = ..()
+	switch(design)
+		if(NODESIGN)
+			desc = "A sack neatly crafted out of paper."
+		if(NANOTRASEN)
+			desc = "A standard Nanotrasen paper lunch sack for loyal employees on the go."
+		if(SYNDI)
+			desc = "The design on this paper sack is a remnant of the notorious 'SyndieSnacks' program."
+		if(HEART)
+			desc = "A paper sack with a heart etched onto the side."
+		if(SMILE)
+			desc = "A paper sack with a crude smile etched onto the side."
+
+/obj/item/storage/box/papersack/update_icon_state()
+	item_state = "paperbag_[design]"
+	if(!length(contents))
 		icon_state = "[item_state]"
-	else icon_state = "[item_state]_closed"
+	else
+		icon_state = "[item_state]_closed"
 
 /obj/item/storage/box/papersack/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/pen))
@@ -746,19 +762,7 @@
 			return
 		to_chat(usr, "<span class='notice'>You make some modifications to [src] using your pen.</span>")
 		design = switchDesign
-		icon_state = "paperbag_[design]"
-		item_state = "paperbag_[design]"
-		switch(design)
-			if(NODESIGN)
-				desc = "A sack neatly crafted out of paper."
-			if(NANOTRASEN)
-				desc = "A standard Nanotrasen paper lunch sack for loyal employees on the go."
-			if(SYNDI)
-				desc = "The design on this paper sack is a remnant of the notorious 'SyndieSnacks' program."
-			if(HEART)
-				desc = "A paper sack with a heart etched onto the side."
-			if(SMILE)
-				desc = "A paper sack with a crude smile etched onto the side."
+		update_appearance(UPDATE_DESC|UPDATE_ICON_STATE)
 		return
 	else if(is_sharp(W))
 		if(!contents.len)

code/game/objects/items/weapons/storage/fancy.dm

@@ -18,10 +18,8 @@
 	resistance_flags = FLAMMABLE
 	var/icon_type
 
-/obj/item/storage/fancy/update_icon(itemremoved = 0)
-	var/total_contents = length(contents) - itemremoved
-	icon_state = "[icon_type]box[total_contents]"
-	return
+/obj/item/storage/fancy/update_icon_state()
+	icon_state = "[icon_type]box[length(contents)]"
 
 /obj/item/storage/fancy/examine(mob/user)
 	. = ..()
@@ -48,23 +46,23 @@
 	foldable = /obj/item/stack/sheet/cardboard
 	foldable_amt = 1
 
-/obj/item/storage/fancy/donut_box/update_icon()
-	overlays.Cut()
-
+/obj/item/storage/fancy/donut_box/update_overlays()
+	. = ..()
 	for(var/I = 1 to length(contents))
 		var/obj/item/reagent_containers/food/snacks/donut/donut = contents[I]
 		var/icon/new_donut_icon = icon('icons/obj/food/containers.dmi', "donut_[donut.donut_sprite_type]")
 		new_donut_icon.Shift(EAST, 3 * (I-1))
-		overlays += new_donut_icon
+		. += new_donut_icon
 
-	overlays += icon('icons/obj/food/containers.dmi', "donutbox_front")
+	. += "donutbox_front"
 
 /obj/item/storage/fancy/donut_box/populate_contents()
 	for(var/I in 1 to storage_slots)
 		new /obj/item/reagent_containers/food/snacks/donut(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/item/storage/fancy/donut_box/empty/populate_contents()
+	update_icon(UPDATE_OVERLAYS)
 	return
 
 /*
@@ -138,11 +136,11 @@
 	new /obj/item/toy/crayon/black(src)
 	update_icon()
 
-/obj/item/storage/fancy/crayons/update_icon()
-	overlays = list() //resets list
-	overlays += image('icons/obj/crayons.dmi',"crayonbox")
+/obj/item/storage/fancy/crayons/update_overlays()
+	. = ..()
+	. += image('icons/obj/crayons.dmi',"crayonbox")
 	for(var/obj/item/toy/crayon/crayon in contents)
-		overlays += image('icons/obj/crayons.dmi',crayon.colourName)
+		. += image('icons/obj/crayons.dmi',crayon.colourName)
 
 /obj/item/storage/fancy/crayons/attackby(obj/item/I, mob/user, params)
 	if(istype(I, /obj/item/toy/crayon))
@@ -184,7 +182,7 @@
 	for(var/I in 1 to storage_slots)
 		new cigarette_type(src)
 
-/obj/item/storage/fancy/cigarettes/update_icon()
+/obj/item/storage/fancy/cigarettes/update_icon_state()
 	icon_state = "[initial(icon_state)][contents.len]"
 
 /obj/item/storage/fancy/cigarettes/attack(mob/living/carbon/M as mob, mob/living/carbon/user as mob)
@@ -325,10 +323,10 @@
 	for(var/I in 1 to storage_slots)
 		new /obj/item/rollingpaper(src)
 
-/obj/item/storage/fancy/rollingpapers/update_icon()
-	overlays.Cut()
+/obj/item/storage/fancy/rollingpapers/update_overlays()
+	. = ..()
 	if(!contents.len)
-		overlays += "[icon_state]_empty"
+		. += "[icon_state]_empty"
 
 /*
  * Vial Box
@@ -364,15 +362,18 @@
 	. = ..()
 	update_icon()
 
-/obj/item/storage/lockbox/vials/update_icon()
+/obj/item/storage/lockbox/vials/update_icon_state()
 	icon_state = "vialbox[length(contents)]"
 	cut_overlays()
+
+/obj/item/storage/lockbox/vials/update_overlays()
+	. = ..()
 	if(!broken)
-		overlays += image(icon, src, "led[locked]")
+		. += "led[locked]"
 		if(locked)
-			overlays += image(icon, src, "cover")
+			. += "cover"
 	else
-		overlays += image(icon, src, "ledb")
+		. += "ledb"
 
 /obj/item/storage/lockbox/vials/attackby(obj/item/I, mob/user, params)
 	..()

code/game/objects/items/weapons/storage/storage.dm

@@ -460,7 +460,7 @@
 
 	if(istype(src, /obj/item/storage/fancy))
 		var/obj/item/storage/fancy/F = src
-		F.update_icon(TRUE)
+		F.update_icon()
 
 	for(var/_M in mobs_viewing)
 		var/mob/M = _M

code/game/objects/items/weapons/storage/toolbox.dm

@@ -24,16 +24,16 @@
 	. = ..()
 	if(has_latches)
 		if(prob(10))
-			latches = "double_latch"
 			if(prob(1))
 				latches = "triple_latch"
-	update_icon()
+			else
+				latches = "double_latch"
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/item/storage/toolbox/update_icon()
-	..()
-	cut_overlays()
+/obj/item/storage/toolbox/update_overlays()
+	. = ..()
 	if(has_latches)
-		add_overlay(latches)
+		. += latches
 
 /obj/item/storage/toolbox/emergency
 	name = "emergency toolbox"

code/game/objects/items/weapons/storage/wallets.dm

@@ -36,17 +36,16 @@
 	if(.)
 		if(W == front_id)
 			front_id = null
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 
 /obj/item/storage/wallet/handle_item_insertion(obj/item/W as obj, prevent_warning = 0)
 	. = ..(W, prevent_warning)
 	if(.)
 		if(!front_id && istype(W, /obj/item/card/id))
 			front_id = W
-			update_icon()
-
-/obj/item/storage/wallet/update_icon()
+			update_icon(UPDATE_ICON_STATE)
 
+/obj/item/storage/wallet/update_icon_state()
 	if(front_id)
 		switch(front_id.icon_state)
 			if("silver")
@@ -112,7 +111,7 @@
 	desc = "A cheap, [item_color] wallet from the arcade."
 	icon_state = "[item_color]_wallet"
 
-/obj/item/storage/wallet/color/update_icon()
+/obj/item/storage/wallet/color/update_icon_state()
 	if(front_id)
 		switch(front_id.icon_state)
 			if("silver")

code/game/objects/items/weapons/stunbaton.dm

@@ -59,7 +59,7 @@
 	user.visible_message("<span class='suicide'>[user] is putting the live [name] in [user.p_their()] mouth! It looks like [user.p_theyre()] trying to commit suicide.</span>")
 	return FIRELOSS
 
-/obj/item/melee/baton/update_icon()
+/obj/item/melee/baton/update_icon_state()
 	if(turned_on)
 		icon_state = "[base_icon]_active"
 	else if(!cell)
@@ -97,7 +97,7 @@
 	if(cell.rigged)
 		cell = null
 		turned_on = FALSE
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 	if(cell.charge < (hitcost)) // If after the deduction the baton doesn't have enough charge for a stun hit it turns off.
 		turned_on = FALSE
 		update_icon()
@@ -117,7 +117,7 @@
 		I.forceMove(src)
 		cell = I
 		to_chat(user, "<span class='notice'>You install [I] into [src].</span>")
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/item/melee/baton/screwdriver_act(mob/living/user, obj/item/I)
 	if(!cell)
@@ -131,7 +131,7 @@
 	cell.update_icon()
 	cell = null
 	turned_on = FALSE
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/melee/baton/attack_self(mob/user)
 	if(cell?.charge >= hitcost)

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

@@ -61,7 +61,7 @@
 				if(!silent)
 					to_chat(C, "<span class='warning'>You are not wearing a suitable mask or helmet.</span>")
 				return FALSE
-			if(M.mask_adjusted) // If the mask is equipped but pushed down
+			if(M.up) // If the mask is equipped but pushed away
 				M.adjustmask(C) // Adjust it back
 
 		if(!silent)

code/game/objects/items/weapons/tape.dm

@@ -10,8 +10,7 @@
 
 /obj/item/stack/tape_roll/New(loc, amount=null)
 	..()
-
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/item/stack/tape_roll/attack(mob/living/carbon/human/M, mob/living/user)
 	if(!istype(M)) //What good is a duct tape mask if you are unable to speak?
@@ -42,7 +41,7 @@
 	M.equip_to_slot(G, slot_wear_mask)
 	G.add_fingerprint(user)
 
-/obj/item/stack/tape_roll/update_icon()
+/obj/item/stack/tape_roll/update_icon_state()
 	var/amount = get_amount()
 	if((amount <= 2) && (amount > 0))
 		icon_state = "taperoll"
@@ -54,4 +53,3 @@
 		icon_state = "taperoll-4"
 	else
 		icon_state = "taperoll-4"
-	..()

code/game/objects/items/weapons/twohanded.dm

@@ -202,9 +202,8 @@
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 100, ACID = 30)
 	resistance_flags = FIRE_PROOF
 
-/obj/item/twohanded/fireaxe/update_icon()  //Currently only here to fuck with the on-mob icons.
+/obj/item/twohanded/fireaxe/update_icon_state()  //Currently only here to fuck with the on-mob icons.
 	icon_state = "fireaxe[wielded]"
-	..()
 
 /obj/item/twohanded/fireaxe/afterattack(atom/A, mob/user, proximity)
 	if(!proximity)
@@ -221,7 +220,7 @@
 	force_wielded = 23
 	needs_permit = TRUE
 
-/obj/item/twohanded/fireaxe/boneaxe/update_icon()
+/obj/item/twohanded/fireaxe/boneaxe/update_icon_state()
 	icon_state = "bone_axe[wielded]"
 
 /obj/item/twohanded/fireaxe/energized
@@ -231,7 +230,7 @@
 	var/charge = 30
 	var/max_charge = 30
 
-/obj/item/twohanded/fireaxe/energized/update_icon()
+/obj/item/twohanded/fireaxe/energized/update_icon_state()
 	if(wielded)
 		icon_state = "fireaxe2"
 	else
@@ -298,14 +297,13 @@
 	if(!blade_color)
 		blade_color = pick("red", "blue", "green", "purple")
 
-/obj/item/twohanded/dualsaber/update_icon()
+/obj/item/twohanded/dualsaber/update_icon_state()
 	if(wielded)
 		icon_state = "dualsaber[blade_color][wielded]"
 		set_light(brightness_on, l_color=colormap[blade_color])
 	else
 		icon_state = "dualsaber0"
 		set_light(0)
-	..()
 
 /obj/item/twohanded/dualsaber/attack(mob/target, mob/living/user)
 	if(HAS_TRAIT(user, TRAIT_HULK))
@@ -406,7 +404,7 @@
 	needs_permit = TRUE
 	var/icon_prefix = "spearglass"
 
-/obj/item/twohanded/spear/update_icon()
+/obj/item/twohanded/spear/update_icon_state()
 	icon_state = "[icon_prefix][wielded]"
 
 /obj/item/twohanded/spear/CheckParts(list/parts_list)
@@ -609,12 +607,11 @@
 	attack_verb = list("sawed", "cut", "hacked", "carved", "cleaved", "butchered", "felled", "timbered")
 	sharp = TRUE
 
-/obj/item/twohanded/chainsaw/update_icon()
+/obj/item/twohanded/chainsaw/update_icon_state()
 	if(wielded)
 		icon_state = "chainsaw[wielded]"
 	else
 		icon_state = "chainsaw0"
-	..()
 
 /obj/item/twohanded/chainsaw/attack(mob/living/target, mob/living/user)
 	if(wielded)
@@ -685,9 +682,8 @@
 	if(charged < 2)
 		charged++
 
-/obj/item/twohanded/singularityhammer/update_icon()  //Currently only here to fuck with the on-mob icons.
+/obj/item/twohanded/singularityhammer/update_icon_state()  //Currently only here to fuck with the on-mob icons.
 	icon_state = "singulohammer[wielded]"
-	..()
 
 /obj/item/twohanded/singularityhammer/proc/vortex(turf/pull, mob/wielder)
 	for(var/atom/movable/X in orange(5, pull))
@@ -762,9 +758,8 @@
 		L.Stun(6 SECONDS)
 		shock(L)
 
-/obj/item/twohanded/mjollnir/update_icon()  //Currently only here to fuck with the on-mob icons.
+/obj/item/twohanded/mjollnir/update_icon_state()  //Currently only here to fuck with the on-mob icons.
 	icon_state = "mjollnir[wielded]"
-	..()
 
 /obj/item/twohanded/knighthammer
 	name = "singuloth knight's hammer"
@@ -793,9 +788,8 @@
 	if(charged < 5)
 		charged++
 
-/obj/item/twohanded/knighthammer/update_icon()  //Currently only here to fuck with the on-mob icons.
+/obj/item/twohanded/knighthammer/update_icon_state()  //Currently only here to fuck with the on-mob icons.
 	icon_state = "knighthammer[wielded]"
-	..()
 
 /obj/item/twohanded/knighthammer/afterattack(atom/A, mob/user, proximity)
 	if(!proximity)

code/game/objects/obj_defense.dm

@@ -209,8 +209,8 @@ GLOBAL_DATUM_INIT(acid_overlay, /mutable_appearance, mutable_appearance('icons/e
 	if(!(resistance_flags & ON_FIRE) && (resistance_flags & FLAMMABLE) && !(resistance_flags & FIRE_PROOF))
 		resistance_flags |= ON_FIRE
 		SSfires.processing[src] = src
-		add_overlay(GLOB.fire_overlay, TRUE)
-		return 1
+		add_overlay(custom_fire_overlay ? custom_fire_overlay : GLOB.fire_overlay)
+		return TRUE
 
 ///called when the obj is destroyed by fire
 /obj/proc/burn()
@@ -222,7 +222,7 @@ GLOBAL_DATUM_INIT(acid_overlay, /mutable_appearance, mutable_appearance('icons/e
 /obj/proc/extinguish()
 	if(resistance_flags & ON_FIRE)
 		resistance_flags &= ~ON_FIRE
-		cut_overlay(GLOB.fire_overlay, TRUE)
+		cut_overlay(custom_fire_overlay ? custom_fire_overlay : GLOB.fire_overlay, TRUE)
 		SSfires.processing -= src
 
 ///Called when the obj is hit by a tesla bolt.

code/game/objects/objs.dm

@@ -18,6 +18,7 @@
 	var/damage_deflection = 0
 
 	var/resistance_flags = NONE // INDESTRUCTIBLE
+	var/custom_fire_overlay // Update_fire_overlay will check if a different icon state should be used
 
 	var/acid_level = 0 //how much acid is on that obj
 
@@ -168,9 +169,6 @@
 /obj/proc/interact(mob/user)
 	return
 
-/obj/proc/update_icon()
-	SEND_SIGNAL(src, COMSIG_OBJ_UPDATE_ICON)
-
 /mob/proc/unset_machine()
 	if(machine)
 		UnregisterSignal(machine, COMSIG_PARENT_QDELETING)

code/game/objects/structures/bedsheet_bin.dm

@@ -284,7 +284,7 @@ LINEN BINS
 		. += "There are [amount] bed sheets in the bin."
 
 
-/obj/structure/bedsheetbin/update_icon()
+/obj/structure/bedsheetbin/update_icon_state()
 	switch(amount)
 		if(0)
 			icon_state = "linenbin-empty"
@@ -313,6 +313,7 @@ LINEN BINS
 		I.forceMove(src)
 		sheets.Add(I)
 		amount++
+		update_icon(UPDATE_ICON_STATE)
 		to_chat(user, "<span class='notice'>You put [I] in [src].</span>")
 	else if(amount && !hidden && I.w_class < WEIGHT_CLASS_BULKY)	//make sure there's sheets to hide it among, make sure nothing else is hidden in there.
 		if(I.flags & ABSTRACT)
@@ -346,7 +347,7 @@ LINEN BINS
 			hidden.loc = user.loc
 			to_chat(user, "<span class='notice'>[hidden] falls out of [B]!</span>")
 			hidden = null
-
+		update_icon(UPDATE_ICON_STATE)
 
 	add_fingerprint(user)
 
@@ -365,7 +366,7 @@ LINEN BINS
 
 		B.loc = loc
 		to_chat(user, "<span class='notice'>You telekinetically remove [B] from [src].</span>")
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 		if(hidden)
 			hidden.loc = loc

code/game/objects/structures/coathanger.dm

@@ -9,44 +9,42 @@
 /obj/structure/coatrack/attack_hand(mob/user as mob)
 	user.visible_message("[user] takes [coat] off \the [src].", "You take [coat] off the \the [src]")
 	if(!user.put_in_active_hand(coat))
-		coat.loc = get_turf(user)
+		coat.forceMove(get_turf(user))
 	coat = null
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/coatrack/attackby(obj/item/W as obj, mob/user as mob, params)
-	var/can_hang = 0
+	var/can_hang = FALSE
 	for(var/T in allowed)
 		if(istype(W,T))
-			can_hang = 1
+			can_hang = TRUE
 	if(can_hang && !coat)
 		user.visible_message("[user] hangs [W] on \the [src].", "You hang [W] on the \the [src]")
 		coat = W
 		user.drop_item(src)
-		coat.loc = src
-		update_icon()
-	else
-		return ..()
+		coat.forceMove(src)
+		update_icon(UPDATE_OVERLAYS)
+		return
+	return ..()
 
 /obj/structure/coatrack/CanPass(atom/movable/mover, turf/target, height=0)
-	var/can_hang = 0
+	var/can_hang = FALSE
 	for(var/T in allowed)
 		if(istype(mover,T))
-			can_hang = 1
-
+			can_hang = TRUE
 	if(can_hang && !coat)
-		src.visible_message("[mover] lands on \the [src].")
+		visible_message("[mover] lands on \the [src].")
 		coat = mover
-		coat.loc = src
-		update_icon()
-		return 0
-	else
-		return 1
+		coat.forceMove(src)
+		update_icon(UPDATE_OVERLAYS)
+		return
+	return ..()
 
-/obj/structure/coatrack/update_icon()
-	overlays.Cut()
+/obj/structure/coatrack/update_overlays()
+	. = ..()
 	if(istype(coat, /obj/item/clothing/suit/storage/labcoat))
-		overlays += image(icon, icon_state = "coat_lab")
+		. += "coat_lab"
 	if(istype(coat, /obj/item/clothing/suit/storage/labcoat/cmo))
-		overlays += image(icon, icon_state = "coat_cmo")
+		. += "coat_cmo"
 	if(istype(coat, /obj/item/clothing/suit/storage/det_suit))
-		overlays += image(icon, icon_state = "coat_det")
+		. += "coat_det"

code/game/objects/structures/crates_lockers/closets.dm

@@ -24,6 +24,7 @@
 	var/storage_capacity = 30 //This is so that someone can't pack hundreds of items in a locker/crate then open it in a populated area to crash clients.
 	var/material_drop = /obj/item/stack/sheet/metal
 	var/material_drop_amount = 2
+	var/transparent
 
 // Please dont override this unless you absolutely have to
 /obj/structure/closet/Initialize(mapload)
@@ -298,23 +299,22 @@
 		return
 	to_chat(usr, "<span class='warning'>This mob type can't use this verb.</span>")
 
-/obj/structure/closet/update_icon()//Putting the welded stuff in updateicon() so it's easy to overwrite for special cases (Fridges, cabinets, and whatnot)
+/obj/structure/closet/update_icon_state()
 	if(!opened)
-		icon_state = icon_closed
+		icon_state = "[icon_closed][transparent ? "_trans" : ""]"
 	else
-		icon_state = icon_opened
-	update_overlays()
+		icon_state = "[icon_opened][transparent ? "_trans" : ""]"
 
-/obj/structure/closet/proc/update_overlays(transparent = FALSE)
-	cut_overlays()
+/obj/structure/closet/update_overlays()
+	. = ..()
 	if(transparent && opened)
-		add_overlay("[open_door_sprite]_trans")
+		. += "[open_door_sprite]_trans"
 		return
 	if(opened)
-		add_overlay(open_door_sprite)
+		. += open_door_sprite
 		return
 	if(welded)
-		add_overlay("welded")
+		. += "welded"
 
 // Objects that try to exit a locker by stepping were doing so successfully,
 // and due to an oversight in turf/Enter() were going through walls.  That
@@ -399,20 +399,17 @@
 	return TRUE
 
 /obj/structure/closet/bluespace/proc/UpdateTransparency(atom/movable/AM, atom/location)
-	var/transparent = FALSE
+	transparent = FALSE
 	for(var/atom/A in location)
 		if(A.density && A != src && A != AM)
 			transparent = TRUE
 			break
-	icon_opened = transparent ? "bluespace_open_trans" : "bluespace_open"
-	icon_closed = transparent ? "bluespace_trans" : "bluespace"
-	icon_state = opened ? icon_opened : icon_closed
-	update_overlays(transparent)
+	update_icon()
 
 /obj/structure/closet/bluespace/Crossed(atom/movable/AM, oldloc)
 	if(AM.density)
-		icon_state = opened ? "bluespace_open_trans" : "bluespace_trans"
-		update_overlays(TRUE)
+		transparent = TRUE
+		update_icon()
 
 /obj/structure/closet/bluespace/Move(NewLoc, direct) // Allows for "phasing" throug objects but doesn't allow you to stuff your EOC homebois in one of these and push them through walls.
 	var/turf/T = get_turf(NewLoc)

code/game/objects/structures/crates_lockers/closets/coffin.dm

@@ -11,12 +11,15 @@
 	open_sound_volume = 25
 	close_sound_volume = 50
 
-/obj/structure/closet/coffin/update_icon()
+/obj/structure/closet/coffin/update_icon_state()
 	if(!opened)
 		icon_state = icon_closed
 	else
 		icon_state = icon_opened
 
+/obj/structure/closet/coffin/update_overlays()
+	return list()
+
 /obj/structure/closet/coffin/sarcophagus
 	name = "sarcophagus"
 	icon_state = "sarc"

code/game/objects/structures/crates_lockers/closets/fireaxe.dm

@@ -20,7 +20,7 @@
 /obj/structure/closet/fireaxecabinet/populate_contents()
 	fireaxe = new/obj/item/twohanded/fireaxe(src)
 	has_axe = "full"
-	update_icon()	// So its initial icon doesn't show it without the fireaxe
+	update_icon(UPDATE_ICON_STATE)	// So its initial icon doesn't show it without the fireaxe
 
 /obj/structure/closet/fireaxecabinet/examine(mob/user)
 	. = ..()
@@ -37,7 +37,7 @@
 			if(do_after(user, 20 * O.toolspeed, target = src))
 				locked = FALSE
 				to_chat(user, "<span class = 'caution'> You disable the locking modules.</span>")
-				update_icon()
+				update_icon(UPDATE_ICON_STATE)
 			return
 		else if(istype(O, /obj/item))
 			user.changeNext_move(CLICK_CD_MELEE)
@@ -58,7 +58,7 @@
 					smashed = TRUE
 					locked = FALSE
 					localopened = TRUE
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 		return
 	if(istype(O, /obj/item/twohanded/fireaxe) && localopened)
 		if(!fireaxe)
@@ -73,7 +73,7 @@
 			has_axe = "full"
 			contents += F
 			to_chat(user, "<span class='notice'>You place \the [F] back in the [name].</span>")
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 		else
 			if(smashed)
 				return
@@ -107,7 +107,7 @@
 		fireaxe = null
 
 		add_fingerprint(user)
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return
 	if(smashed)
 		return
@@ -119,7 +119,7 @@
 		to_chat(user, "<span class='notice'>You telekinetically remove \the [fireaxe].</span>")
 		has_axe = "empty"
 		fireaxe = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 		return
 	attack_hand(user)
 
@@ -153,7 +153,7 @@
 			to_chat(usr, "<span class='notice'>[src] is empty.</span>")
 	else
 		to_chat(usr, "<span class='notice'>[src] is closed.</span>")
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/closet/fireaxecabinet/attack_ai(mob/user as mob)
 	if(smashed)
@@ -180,14 +180,17 @@
 	else
 		flick("fireaxe_[has_axe]_opening", src)
 	sleep(10)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 
-/obj/structure/closet/fireaxecabinet/update_icon()
+/obj/structure/closet/fireaxecabinet/update_icon_state()
 	if(localopened && !smashed)
 		icon_state = "fireaxe_[has_axe]_open"
-		return
-	icon_state = "fireaxe_[has_axe]_[hitstaken]hits"
+	else
+		icon_state = "fireaxe_[has_axe]_[hitstaken]hits"
+
+/obj/structure/closet/fireaxecabinet/update_overlays()
+	return list()
 
 /obj/structure/closet/fireaxecabinet/open()
 	return

code/game/objects/structures/crates_lockers/closets/gimmick.dm

@@ -10,12 +10,15 @@
 	close_sound_volume = 50
 	max_integrity = 70
 
-/obj/structure/closet/cabinet/update_icon()
+/obj/structure/closet/cabinet/update_icon_state()
 	if(!opened)
 		icon_state = icon_closed
 	else
 		icon_state = icon_opened
 
+/obj/structure/closet/cabinet/update_overlays()
+	return list()
+
 /obj/structure/closet/acloset
 	name = "strange closet"
 	desc = "It looks alien!"

code/game/objects/structures/crates_lockers/closets/secure/guncabinet.dm

@@ -21,7 +21,7 @@
 		update_icon()
 
 /obj/structure/closet/secure_closet/guncabinet/update_overlays()
-	cut_overlays()
+	. = list()
 	if(!opened)
 		var/lasers = 0
 		var/ballistics = 0
@@ -43,10 +43,10 @@
 					gun.icon_state = "projectile"
 
 				gun.pixel_x = i*4
-				add_overlay(gun)
+				. += gun
 
-		add_overlay("door")
+		. += "door"
 		if(broken)
-			add_overlay("off")
+			. += "off"
 		else if(locked)
-			add_overlay("locked")
+			. += "locked"

code/game/objects/structures/crates_lockers/closets/secure/secure_closets.dm

@@ -73,7 +73,7 @@
 		locked = FALSE
 		add_overlay("sparking")
 		to_chat(user, "<span class='notice'>You break the lock on [src].</span>")
-		addtimer(CALLBACK(src, .proc/update_icon), 1 SECONDS)
+		addtimer(CALLBACK(src, /atom/.proc/update_icon), 1 SECONDS)
 
 /obj/structure/closet/secure_closet/attack_hand(mob/user)
 	add_fingerprint(user)

code/game/objects/structures/crates_lockers/closets/statue.dm

@@ -105,9 +105,12 @@
 /obj/structure/closet/statue/verb_toggleopen()
 	return
 
-/obj/structure/closet/statue/update_icon()
+/obj/structure/closet/statue/update_icon_state()
 	return
 
+/obj/structure/closet/statue/update_overlays()
+	return list()
+
 /obj/structure/closet/statue/proc/shatter(mob/user)
 	if(user)
 		user.dust()

code/game/objects/structures/crates_lockers/crates.dm

@@ -15,11 +15,10 @@
 	// A list of beacon names that the crate will announce the arrival of, when delivered.
 	var/list/announce_beacons = list()
 
-/obj/structure/closet/crate/update_icon()
-	..()
-	cut_overlays()
+/obj/structure/closet/crate/update_overlays()
+	. = ..()
 	if(manifest)
-		add_overlay("manifest")
+		. += "manifest"
 
 /obj/structure/closet/crate/can_open()
 	return TRUE
@@ -175,15 +174,15 @@
 	locked = TRUE
 	can_be_emaged = TRUE
 
-/obj/structure/closet/crate/secure/update_icon()
-	..()
+/obj/structure/closet/crate/secure/update_overlays()
+	. = ..()
 	if(broken)
-		add_overlay(emag)
+		. += emag
 		return
 	if(locked)
-		add_overlay(redlight)
+		. += redlight
 	else
-		add_overlay(greenlight)
+		. += greenlight
 
 /obj/structure/closet/crate/secure/take_damage(damage_amount, damage_type = BRUTE, damage_flag = 0, sound_effect = 1)
 	if(prob(tamperproof) && damage_amount >= DAMAGE_PRECISION)

code/game/objects/structures/crates_lockers/largecrate.dm

@@ -10,11 +10,10 @@
 	. = ..()
 	update_icon()
 
-/obj/structure/largecrate/update_icon()
-	..()
-	overlays.Cut()
+/obj/structure/largecrate/update_overlays()
+	. = ..()
 	if(manifest)
-		overlays += "manifest"
+		. += "manifest"
 
 /obj/structure/largecrate/attack_hand(mob/user as mob)
 	if(manifest)

code/game/objects/structures/depot.dm

@@ -86,7 +86,7 @@
 	if(istype(depotarea))
 		if(!depotarea.used_self_destruct)
 			depotarea.used_self_destruct = TRUE // Silences all further alerts from this point onwards.
-			depotarea.updateicon()
+			depotarea.update_state()
 		depotarea.shields_down()
 	else
 		log_debug("[src] at [x],[y],[z] failed depotarea istype check during Initialize()! Either it was spawned outside the depot area (bad idea), or a bug is happening.")
@@ -103,7 +103,7 @@
 		depotarea = get_area(src)
 	if(istype(depotarea))
 		depotarea.destroyed = TRUE
-		depotarea.updateicon()
+		depotarea.update_state()
 
 	for(var/obj/structure/closet/L in range(30, T))
 		for(var/obj/O in L)

code/game/objects/structures/displaycase.dm

@@ -28,7 +28,7 @@
 				trophy_message = showpiece_entry["trophy_message"]
 	if(start_showpiece_type)
 		showpiece = new start_showpiece_type (src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/displaycase/Destroy()
 	QDEL_NULL(electronics)
@@ -81,7 +81,7 @@
 		open = TRUE
 		new /obj/item/shard(drop_location())
 		playsound(src, "shatter", 70, TRUE)
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 		trigger_alarm()
 
 /obj/structure/displaycase/proc/trigger_alarm()
@@ -95,17 +95,17 @@
 			playsound(src, 'sound/machines/burglar_alarm.ogg', 50, 0)
 			sleep(74) // 7.4 seconds long
 
-/obj/structure/displaycase/update_icon()
-	cut_overlays()
+/obj/structure/displaycase/update_overlays()
+	. = ..()
 	if(broken)
-		add_overlay("glassbox_broken")
+		. += "glassbox_broken"
 	if(showpiece)
 		var/mutable_appearance/showpiece_overlay = mutable_appearance(showpiece.icon, showpiece.icon_state)
 		showpiece_overlay.copy_overlays(showpiece)
 		showpiece_overlay.transform *= 0.6
-		add_overlay(showpiece_overlay)
+		. += showpiece_overlay
 	if(!open && !broken)
-		add_overlay("glassbox_closed")
+		. += "glassbox_closed"
 
 /obj/structure/displaycase/attackby(obj/item/I, mob/user, params)
 	if(I.GetID() && !broken && openable)
@@ -131,7 +131,7 @@
 			broken = FALSE
 			open = FALSE
 			obj_integrity = max_integrity
-			update_icon()
+			update_icon(UPDATE_OVERLAYS)
 	else
 		return ..()
 
@@ -174,7 +174,7 @@
 
 /obj/structure/displaycase/proc/toggle_lock()
 	open = !open
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/displaycase/attack_hand(mob/user)
 	user.changeNext_move(CLICK_CD_MELEE)
@@ -182,7 +182,7 @@
 		to_chat(user, "<span class='notice'>You deactivate the hover field built into the case.</span>")
 		dump()
 		add_fingerprint(user)
-		update_icon()
+		update_icon(UPDATE_OVERLAYS)
 		return
 	else
 	    //prevents remote "kicks" with TK

code/game/objects/structures/door_assembly.dm

@@ -22,7 +22,7 @@
 
 /obj/structure/door_assembly/Initialize(mapload)
 	. = ..()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	update_name()
 
 /obj/structure/door_assembly/Destroy()
@@ -131,7 +131,7 @@
 	else
 		return ..()
 	update_name()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/door_assembly/crowbar_act(mob/user, obj/item/I)
 	if(state != AIRLOCK_ASSEMBLY_NEEDS_SCREWDRIVER )
@@ -152,7 +152,7 @@
 		ae = electronics
 		electronics = null
 		ae.forceMove(loc)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	update_name()
 
 /obj/structure/door_assembly/screwdriver_act(mob/user, obj/item/I)
@@ -189,7 +189,7 @@
 	electronics.forceMove(door)
 	electronics = null
 	qdel(src)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/door_assembly/wirecutter_act(mob/user, obj/item/I)
 	if(state != AIRLOCK_ASSEMBLY_NEEDS_ELECTRONICS)
@@ -203,7 +203,7 @@
 	to_chat(user, "<span class='notice'>You cut the wires from the airlock assembly.</span>")
 	new/obj/item/stack/cable_coil(get_turf(user), 1)
 	state = AIRLOCK_ASSEMBLY_NEEDS_WIRES
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/door_assembly/wrench_act(mob/user, obj/item/I)
 	if(state != AIRLOCK_ASSEMBLY_NEEDS_WIRES)
@@ -256,17 +256,18 @@
 			return
 		to_chat(user, "<span class='notice'>You disassemble the airlock assembly.</span>")
 		deconstruct(TRUE)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/structure/door_assembly/update_icon()
-	overlays.Cut()
+/obj/structure/door_assembly/update_overlays()
+	. = ..()
 	if(!glass)
-		overlays += get_airlock_overlay("fill_construction", icon)
+		. += get_airlock_overlay("fill_construction", icon)
 	else if(glass)
-		overlays += get_airlock_overlay("glass_construction", overlays_file)
-	overlays += get_airlock_overlay("panel_c[state+1]", overlays_file)
+		. += get_airlock_overlay("glass_construction", overlays_file)
+	. += get_airlock_overlay("panel_c[state+1]", overlays_file)
 
-/obj/structure/door_assembly/proc/update_name()
+/obj/structure/door_assembly/update_name()
+	. = ..()
 	name = ""
 	switch(state)
 		if(AIRLOCK_ASSEMBLY_NEEDS_WIRES)
@@ -289,7 +290,7 @@
 	if(electronics)
 		target.electronics = source.electronics
 		source.electronics.forceMove(target)
-	target.update_icon()
+	target.update_icon(UPDATE_OVERLAYS)
 	target.update_name()
 	qdel(source)
 

code/game/objects/structures/electricchair.dm

@@ -6,10 +6,11 @@
 	var/obj/item/assembly/shock_kit/part = null
 	var/last_time = 1.0
 	var/delay_time = 50
+	var/shocking = FALSE
 
 /obj/structure/chair/e_chair/Initialize(mapload, obj/item/assembly/shock_kit/sk)
 	. = ..()
-	overlays += image('icons/obj/chairs.dmi', src, "echair_over", MOB_LAYER + 1, dir)
+	update_icon(UPDATE_OVERLAYS)
 
 	if(sk)
 		part = sk
@@ -50,17 +51,25 @@
 
 /obj/structure/chair/e_chair/rotate()
 	..()
-	overlays.Cut()
-	overlays += image('icons/obj/chairs.dmi', src, "echair_over", MOB_LAYER + 1, dir)	//there's probably a better way of handling this, but eh. -Pete
+	update_icon(UPDATE_OVERLAYS)
+
+/obj/structure/chair/e_chair/update_icon_state()
+	icon_state = "echair[shocking]"
+
+/obj/structure/chair/e_chair/update_overlays()
+	. = ..()
+	. += image('icons/obj/chairs.dmi', src, "echair_over", MOB_LAYER + 1, dir)
 
 /obj/structure/chair/e_chair/proc/shock()
 	if(last_time + delay_time > world.time)
 		return
 	last_time = world.time
 
-	icon_state = "echair1"
+	shocking = TRUE
+	update_icon(UPDATE_ICON_STATE)
 	spawn(delay_time)
-		icon_state = "echair0"
+		shocking = FALSE
+		update_icon(UPDATE_ICON_STATE)
 
 	// special power handling
 	var/area/A = get_area(src)
@@ -70,7 +79,7 @@
 		return
 	A.use_power(5000, EQUIP)
 	var/light = A.power_light
-	A.updateicon()
+	A.update_icon(UPDATE_ICON_STATE)
 
 	flick("echair_shock", src)
 	do_sparks(12, 1, src)
@@ -83,4 +92,4 @@
 			spawn(1)
 				buckled_mob.electrocute_act(110, src, 1)
 	A.power_light = light
-	A.updateicon()
+	A.update_icon(UPDATE_ICON_STATE)

code/game/objects/structures/engicart.dm

@@ -37,49 +37,49 @@
 			if(!myglass)
 				put_in_cart(I, user)
 				myglass=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/stack/sheet/metal))
 			if(!mymetal)
 				put_in_cart(I, user)
 				mymetal=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/stack/sheet/plasteel))
 			if(!myplasteel)
 				put_in_cart(I, user)
 				myplasteel=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/flashlight))
 			if(!myflashlight)
 				put_in_cart(I, user)
 				myflashlight=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/storage/toolbox/mechanical))
 			if(!mybluetoolbox)
 				put_in_cart(I, user)
 				mybluetoolbox=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/storage/toolbox/electrical))
 			if(!myyellowtoolbox)
 				put_in_cart(I, user)
 				myyellowtoolbox=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/storage/toolbox))
 			if(!myredtoolbox)
 				put_in_cart(I, user)
 				myredtoolbox=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/wrench))
@@ -120,6 +120,7 @@
 	var/datum/browser/popup = new(user, "engicart", name, 240, 160)
 	popup.set_content(dat)
 	popup.open()
+
 /obj/structure/engineeringcart/Topic(href, href_list)
 	if(!in_range(src, usr))
 		return
@@ -162,22 +163,22 @@
 			to_chat(user, "<span class='notice'>You take [myyellowtoolbox] from [src].</span>")
 			myyellowtoolbox = null
 
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	updateUsrDialog()
 
-/obj/structure/engineeringcart/update_icon()
-	overlays.Cut()
+/obj/structure/engineeringcart/update_overlays()
+	. = ..()
 	if(myglass)
-		overlays += "cart_glass"
+		. += "cart_glass"
 	if(mymetal)
-		overlays += "cart_metal"
+		. += "cart_metal"
 	if(myplasteel)
-		overlays += "cart_plasteel"
+		. += "cart_plasteel"
 	if(myflashlight)
-		overlays += "cart_flashlight"
+		. += "cart_flashlight"
 	if(mybluetoolbox)
-		overlays += "cart_bluetoolbox"
+		. += "cart_bluetoolbox"
 	if(myredtoolbox)
-		overlays += "cart_redtoolbox"
+		. += "cart_redtoolbox"
 	if(myyellowtoolbox)
-		overlays += "cart_yellowtoolbox"
+		. += "cart_yellowtoolbox"

code/game/objects/structures/extinguisher.dm

@@ -45,7 +45,7 @@
 		return
 	playsound(loc, 'sound/machines/click.ogg', 15, TRUE, -3)
 	opened = !opened
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/extinguisher_cabinet/Destroy()
 	QDEL_NULL(has_extinguisher)
@@ -59,7 +59,7 @@
 /obj/structure/extinguisher_cabinet/handle_atom_del(atom/A)
 	if(A == has_extinguisher)
 		has_extinguisher = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/extinguisher_cabinet/attackby(obj/item/O, mob/user, params)
 	if(isrobot(user) || isalien(user))
@@ -71,17 +71,17 @@
 			user.drop_item(O)
 			contents += O
 			has_extinguisher = O
-			update_icon()
+			update_icon(UPDATE_ICON_STATE)
 			to_chat(user, "<span class='notice'>You place [O] in [src].</span>")
 			return TRUE
 		else
 			playsound(loc, 'sound/machines/click.ogg', 15, TRUE, -3)
 			opened = !opened
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 	else if(user.a_intent != INTENT_HARM)
 		playsound(loc, 'sound/machines/click.ogg', 15, TRUE, -3)
 		opened = !opened
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 	else
 		return ..()
 
@@ -122,7 +122,7 @@
 	else
 		playsound(loc, 'sound/machines/click.ogg', 15, TRUE, -3)
 		opened = !opened
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/extinguisher_cabinet/attack_tk(mob/user)
 	if(has_extinguisher)
@@ -135,7 +135,7 @@
 	else
 		playsound(loc, 'sound/machines/click.ogg', 15, TRUE, -3)
 		opened = !opened
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/extinguisher_cabinet/obj_break(damage_flag)
 	if(!broken && !(flags & NODECONSTRUCT))
@@ -144,7 +144,7 @@
 		if(has_extinguisher)
 			has_extinguisher.forceMove(loc)
 			has_extinguisher = null
-		update_icon()
+		update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/extinguisher_cabinet/deconstruct(disassembled = TRUE)
 	if(!(flags & NODECONSTRUCT))
@@ -154,7 +154,7 @@
 			has_extinguisher = null
 	qdel(src)
 
-/obj/structure/extinguisher_cabinet/update_icon()
+/obj/structure/extinguisher_cabinet/update_icon_state()
 	if(!opened)
 		icon_state = "extinguisher_closed"
 		return

code/game/objects/structures/false_walls.dm

@@ -84,7 +84,7 @@
 	opening = FALSE
 	update_icon()
 
-/obj/structure/falsewall/update_icon()
+/obj/structure/falsewall/update_icon_state()
 	if(opening)
 		smoothing_flags = NONE
 		clear_smooth_overlays()

code/game/objects/structures/grille.dm

@@ -50,9 +50,9 @@
 
 /obj/structure/grille/take_damage(damage_amount, damage_type = BRUTE, damage_flag = 0, sound_effect = 1, attack_dir)
 	. = ..()
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
-/obj/structure/grille/update_icon()
+/obj/structure/grille/update_icon_state()
 	if(QDELETED(src) || broken)
 		return
 

code/game/objects/structures/inflatable.dm

@@ -41,7 +41,7 @@
 	T.air_update_turf(TRUE)
 
 /obj/structure/inflatable/CanPass(atom/movable/mover, turf/target, height=0)
-	return 0
+	return
 
 /obj/structure/inflatable/CanAtmosPass(turf/T)
 	return !density
@@ -105,14 +105,12 @@
 
 /obj/structure/inflatable/door //Based on mineral door code
 	name = "inflatable door"
-
-	icon = 'icons/obj/inflatable.dmi'
 	icon_state = "door_closed"
 	torn = /obj/item/inflatable/door/torn
 	intact = /obj/item/inflatable/door
 
 	var/state_open = FALSE
-	var/isSwitchingStates = FALSE
+	var/is_operating = FALSE
 
 /obj/structure/inflatable/door/detailed_examine()
 	return "Click the door to open or close it. It only stops air while closed.<br>\
@@ -123,10 +121,10 @@
 		return
 	else if(isrobot(user)) //but cyborgs can
 		if(get_dist(user,src) <= 1) //not remotely though
-			return TryToSwitchState(user)
+			return try_to_operate(user)
 
 /obj/structure/inflatable/door/attack_hand(mob/user as mob)
-	return TryToSwitchState(user)
+	return try_to_operate(user)
 
 /obj/structure/inflatable/door/CanPass(atom/movable/mover, turf/target, height=0)
 	if(istype(mover, /obj/effect/beam))
@@ -136,8 +134,8 @@
 /obj/structure/inflatable/door/CanAtmosPass(turf/T)
 	return !density
 
-/obj/structure/inflatable/door/proc/TryToSwitchState(atom/user)
-	if(isSwitchingStates)
+/obj/structure/inflatable/door/proc/try_to_operate(atom/user)
+	if(is_operating)
 		return
 	if(ismob(user))
 		var/mob/M = user
@@ -147,42 +145,28 @@
 			if(iscarbon(M))
 				var/mob/living/carbon/C = M
 				if(!C.handcuffed)
-					SwitchState()
+					operate()
 			else
-				SwitchState()
+				operate()
 	else if(istype(user, /obj/mecha))
-		SwitchState()
+		operate()
 
-/obj/structure/inflatable/door/proc/SwitchState()
-	if(state_open)
-		Close()
+/obj/structure/inflatable/door/proc/operate()
+	is_operating = TRUE
+	//playsound(loc, 'sound/effects/stonedoor_openclose.ogg', 100, 1)
+	if(!state_open)
+		flick("door_opening",src)
 	else
-		Open()
+		flick("door_closing",src)
+	sleep(10)
+	density = !density
+	opacity = !opacity
+	state_open = !state_open
+	update_icon(UPDATE_ICON_STATE)
+	is_operating = FALSE
 	air_update_turf(1)
 
-/obj/structure/inflatable/door/proc/Open()
-	isSwitchingStates = TRUE
-	//playsound(loc, 'sound/effects/stonedoor_openclose.ogg', 100, 1)
-	flick("door_opening",src)
-	sleep(10)
-	density = FALSE
-	opacity = FALSE
-	state_open = TRUE
-	update_icon()
-	isSwitchingStates = FALSE
-
-/obj/structure/inflatable/door/proc/Close()
-	isSwitchingStates = TRUE
-	//playsound(loc, 'sound/effects/stonedoor_openclose.ogg', 100, 1)
-	flick("door_closing",src)
-	sleep(10)
-	density = TRUE
-	opacity = FALSE
-	state_open = FALSE
-	update_icon()
-	isSwitchingStates = FALSE
-
-/obj/structure/inflatable/door/update_icon()
+/obj/structure/inflatable/door/update_icon_state()
 	if(state_open)
 		icon_state = "door_open"
 	else

code/game/objects/structures/janicart.dm

@@ -40,7 +40,7 @@
 	return
 
 /obj/structure/janitorialcart/on_reagent_change()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/janitorialcart/attackby(obj/item/I, mob/user, params)
 	var/fail_msg = "<span class='notice'>There is already one of those in [src].</span>"
@@ -66,7 +66,7 @@
 			if(!myspray)
 				put_in_cart(I, user)
 				myspray=I
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, fail_msg)
 		else if(istype(I, /obj/item/lightreplacer))
@@ -79,7 +79,7 @@
 			if(signs < max_signs)
 				put_in_cart(I, user)
 				signs++
-				update_icon()
+				update_icon(UPDATE_OVERLAYS)
 			else
 				to_chat(user, "<span class='notice'>[src] can't hold any more signs.</span>")
 		else if(istype(I, /obj/item/crowbar))
@@ -163,22 +163,22 @@
 				WARNING("Signs ([signs]) didn't match contents")
 				signs = 0
 
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	updateUsrDialog()
 
 
-/obj/structure/janitorialcart/update_icon()
-	overlays = null
+/obj/structure/janitorialcart/update_overlays()
+	. = ..()
 	if(mybag)
-		overlays += "cart_garbage"
+		. += "cart_garbage"
 	if(mymop)
-		overlays += "cart_mop"
+		. += "cart_mop"
 	if(myspray)
-		overlays += "cart_spray"
+		. += "cart_spray"
 	if(myreplacer)
-		overlays += "cart_replacer"
+		. += "cart_replacer"
 	if(signs)
-		overlays += "cart_sign[signs]"
+		. += "cart_sign[signs]"
 	if(reagents.total_volume > 0)
 		var/image/reagentsImage = image(icon,src,"cart_reagents0")
 		reagentsImage.alpha = 150
@@ -192,4 +192,4 @@
 			if(76 to 100)
 				reagentsImage.icon_state = "cart_reagents4"
 		reagentsImage.icon += mix_color_from_reagents(reagents.reagent_list)
-		add_overlay(reagentsImage)
+		. += reagentsImage

code/game/objects/structures/ladders.dm

@@ -55,7 +55,7 @@
 		down.update_icon()
 	up = down = null
 
-/obj/structure/ladder/update_icon()
+/obj/structure/ladder/update_icon_state()
 	if(up && down)
 		icon_state = "ladder11"
 
@@ -198,5 +198,5 @@
 	. = ..()
 	set_light(light_range, light_power)		//magical glowing anchor
 
-/obj/structure/ladder/unbreakable/dive_point/update_icon()
+/obj/structure/ladder/unbreakable/dive_point/update_icon_state()
 	return

code/game/objects/structures/mineral_doors.dm

@@ -13,7 +13,7 @@
 	rad_insulation = RAD_MEDIUM_INSULATION
 	var/initial_state
 	var/state_open = FALSE
-	var/isSwitchingStates = FALSE
+	var/is_operating = FALSE
 	var/close_delay = -1 //-1 if does not auto close.
 
 	var/hardness = 1
@@ -41,20 +41,20 @@
 /obj/structure/mineral_door/Bumped(atom/user)
 	..()
 	if(!state_open)
-		return TryToSwitchState(user)
+		return try_to_operate(user)
 
 /obj/structure/mineral_door/attack_ai(mob/user) //those aren't machinery, they're just big fucking slabs of a mineral
 	if(isAI(user)) //so the AI can't open it
 		return
 	else if(isrobot(user) && Adjacent(user)) //but cyborgs can, but not remotely
-		return TryToSwitchState(user)
+		return try_to_operate(user)
 
 /obj/structure/mineral_door/attack_hand(mob/user)
-	return TryToSwitchState(user)
+	return try_to_operate(user)
 
 /obj/structure/mineral_door/attack_ghost(mob/user)
 	if(user.can_advanced_admin_interact())
-		SwitchState()
+		operate()
 
 /obj/structure/mineral_door/CanPass(atom/movable/mover, turf/target, height = 0)
 	if(istype(mover, /obj/effect/beam))
@@ -64,8 +64,8 @@
 /obj/structure/mineral_door/CanAtmosPass(turf/T)
 	return !density
 
-/obj/structure/mineral_door/proc/TryToSwitchState(atom/user)
-	if(isSwitchingStates)
+/obj/structure/mineral_door/proc/try_to_operate(atom/user)
+	if(is_operating)
 		return
 	if(isliving(user))
 		var/mob/living/M = user
@@ -75,52 +75,35 @@
 			if(iscarbon(M))
 				var/mob/living/carbon/C = M
 				if(!C.handcuffed)
-					SwitchState()
+					operate()
 			else
-				SwitchState()
+				operate()
 	else if(istype(user, /obj/mecha))
-		SwitchState()
+		operate()
 
-/obj/structure/mineral_door/proc/SwitchState()
-	if(state_open)
-		Close()
+/obj/structure/mineral_door/proc/operate()
+	is_operating = TRUE
+	if(!state_open)
+		playsound(loc, openSound, 100, 1)
+		flick("[initial_state]opening",src)
 	else
-		Open()
-
-/obj/structure/mineral_door/proc/Open()
-	isSwitchingStates = TRUE
-	playsound(loc, openSound, 100, 1)
-	flick("[initial_state]opening",src)
+		var/turf/T = get_turf(src)
+		for(var/mob/living/L in T)
+			return
+		playsound(loc, closeSound, 100, 1)
+		flick("[initial_state]closing",src)
 	sleep(10)
-	density = FALSE
-	opacity = FALSE
-	state_open = TRUE
+	density = !density
+	opacity = !opacity
+	state_open = !state_open
 	air_update_turf(1)
-	update_icon()
-	isSwitchingStates = FALSE
+	update_icon(UPDATE_ICON_STATE)
+	is_operating = FALSE
 
-	if(close_delay != -1)
-		spawn(close_delay)
-			Close()
+	if(state_open && close_delay != -1)
+		addtimer(CALLBACK(src, .proc/operate), close_delay)
 
-/obj/structure/mineral_door/proc/Close()
-	if(isSwitchingStates || !state_open)
-		return
-	var/turf/T = get_turf(src)
-	for(var/mob/living/L in T)
-		return
-	isSwitchingStates = TRUE
-	playsound(loc, closeSound, 100, 1)
-	flick("[initial_state]closing",src)
-	sleep(10)
-	density = TRUE
-	opacity = TRUE
-	state_open = FALSE
-	air_update_turf(1)
-	update_icon()
-	isSwitchingStates = FALSE
-
-/obj/structure/mineral_door/update_icon()
+/obj/structure/mineral_door/update_icon_state()
 	if(state_open)
 		icon_state = "[initial_state]open"
 	else
@@ -180,7 +163,7 @@
 	opacity = FALSE
 	rad_insulation = RAD_VERY_LIGHT_INSULATION
 
-/obj/structure/mineral_door/transparent/Close()
+/obj/structure/mineral_door/transparent/operate()
 	..()
 	set_opacity(0)
 
@@ -235,6 +218,6 @@
 	damageSound = 'sound/effects/attackblob.ogg'
 	sheetType = null
 
-/obj/structure/mineral_door/resin/TryToSwitchState(atom/user)
+/obj/structure/mineral_door/resin/try_to_operate(atom/user)
 	if(isalien(user))
 		return ..()

code/game/objects/structures/mop_bucket.dm

@@ -6,7 +6,7 @@
 	density = TRUE
 	container_type = OPENCONTAINER
 	face_while_pulling = FALSE
-	var/obj/item/mop/mymop = null
+	var/obj/item/mop/stored_mop = null
 	var/amount_per_transfer_from_this = 5 //shit I dunno, adding this so syringes stop runtime erroring. --NeoFite
 
 /obj/structure/mopbucket/Initialize(mapload)
@@ -29,12 +29,12 @@
 
 /obj/structure/mopbucket/attackby(obj/item/W as obj, mob/user as mob, params)
 	if(istype(W, /obj/item/mop))
-		var/obj/item/mop/m = W
-		if(m.reagents.total_volume < m.reagents.maximum_volume)
-			m.wet_mop(src, user)
+		var/obj/item/mop/M = W
+		if(M.reagents.total_volume < M.reagents.maximum_volume)
+			M.wet_mop(src, user)
 			return
-		if(!mymop)
-			m.janicart_insert(user, src)
+		if(!stored_mop)
+			M.janicart_insert(user, src)
 			return
 		to_chat(user, "<span class='notice'>Theres already a mop in the mopbucket.</span>")
 		return
@@ -47,12 +47,12 @@
 	return
 
 /obj/structure/mopbucket/on_reagent_change()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/structure/mopbucket/update_icon()
-	overlays.Cut()
-	if(mymop)
-		overlays += image(icon,"mopbucket_mop")
+/obj/structure/mopbucket/update_overlays()
+	. = ..()
+	if(stored_mop)
+		. += "mopbucket_mop"
 	if(reagents.total_volume > 0)
 		var/image/reagentsImage = image(icon, src, "mopbucket_reagents0")
 		reagentsImage.alpha = 150
@@ -66,15 +66,15 @@
 			if(76 to 100)
 				reagentsImage.icon_state = "mopbucket_reagents4"
 		reagentsImage.icon += mix_color_from_reagents(reagents.reagent_list)
-		add_overlay(reagentsImage)
+		. += reagentsImage
 
 /obj/structure/mopbucket/attack_hand(mob/living/user)
 	. = ..()
-	if(mymop)
-		user.put_in_hands(mymop)
-		to_chat(user, "<span class='notice'>You take [mymop] from [src].</span>")
-		mymop = null
-		update_icon()
+	if(stored_mop)
+		user.put_in_hands(stored_mop)
+		to_chat(user, "<span class='notice'>You take [stored_mop] from [src].</span>")
+		stored_mop = null
+		update_icon(UPDATE_OVERLAYS)
 		return
 
 

code/game/objects/structures/morgue.dm

@@ -40,36 +40,39 @@
 
 /obj/structure/morgue/Initialize()
 	. = ..()
-	update()
+	update_icon(update_state())
 
-/obj/structure/morgue/proc/update()
-	cut_overlays()
-	if(!connected)
-		if(contents.len)
-			var/mob/living/M = locate() in contents
-			var/obj/structure/closet/body_bag/B = locate() in contents
-			if(M==null) M = locate() in B
-
-			if(M)
-				var/mob/dead/observer/G = M.get_ghost()
-				if(M.mind && !M.mind.suicided)
-					if(M.client)
-						status = REVIVABLE
-					else if(G && G.client) //There is a ghost and it is connected to the server
-						status = GHOST_CONNECTED
-					else
-						status = UNREVIVABLE
-				else
-					status = UNREVIVABLE
-			else
-				status = NOT_BODY
-		else
-			status = EMPTY_MORGUE
-		add_overlay("morgue_[status]")
-	else
+/obj/structure/morgue/proc/update_state()
+	. = UPDATE_OVERLAYS
+	if(connected)
 		status = EXTENDED_TRAY
+		return
+	if(!length(contents))
+		status = EMPTY_MORGUE
+		return
+	var/mob/living/M = locate() in contents
+	var/obj/structure/closet/body_bag/B = locate() in contents
+	if(!M)
+		M = locate() in B
+	if(!M)
+		status = NOT_BODY
+		return
+	var/mob/dead/observer/G = M.get_ghost()
+	if(M.mind && !M.mind.suicided)
+		if(M.client)
+			status = REVIVABLE
+			return
+		if(G && G.client) //There is a ghost and it is connected to the server
+			status = GHOST_CONNECTED
+			return
+	status = UNREVIVABLE
+
+/obj/structure/morgue/update_overlays()
+	. = ..()
+	if(!connected)
+		. += "morgue_[status]"
 	if(name != initial(name))
-		add_overlay("morgue_label")
+		. += "morgue_label"
 
 /obj/structure/morgue/examine(mob/user)
 	. = ..()
@@ -110,7 +113,7 @@
 		playsound(loc, open_sound, 50, 1)
 		connect()
 	add_fingerprint(user)
-	update()
+	update_icon(update_state())
 	return
 
 /obj/structure/morgue/attackby(P as obj, mob/user as mob, params)
@@ -118,7 +121,7 @@
 		var/t = rename_interactive(user, P)
 		if(isnull(t))
 			return
-		update()
+		update_icon(UPDATE_OVERLAYS)
 		add_fingerprint(user)
 		return
 	return ..()
@@ -127,7 +130,7 @@
 	if(name != initial(name))
 		to_chat(user, "<span class='notice'>You cut the tag off the morgue.</span>")
 		name = initial(name)
-		update()
+		update_icon(UPDATE_OVERLAYS)
 		return TRUE
 
 /obj/structure/morgue/relaymove(mob/user as mob)
@@ -196,7 +199,7 @@
 			if(!( A.anchored ))
 				A.forceMove(connected)
 		connected.connected = null
-		connected.update()
+		connected.update_icon(UPDATE_OVERLAYS)
 		add_fingerprint(user)
 		qdel(src)
 		return
@@ -256,17 +259,18 @@
 
 /obj/structure/crematorium/Initialize(mapload)
 	. = ..()
-	update()
+	update_icon(UPDATE_OVERLAYS)
 
-/obj/structure/crematorium/proc/update()
-	cut_overlays()
-	if(!connected)
-		add_overlay("crema_closed")
-		if(cremating)
-			add_overlay("crema_active")
-			return
-		if(contents.len)
-			add_overlay("crema_full")
+/obj/structure/crematorium/update_overlays()
+	. = ..()
+	if(connected)
+		return
+	. += "crema_closed"
+	if(cremating)
+		. += "crema_active"
+		return
+	if(length(contents))
+		. += "crema_full"
 
 /obj/structure/crematorium/ex_act(severity)
 	switch(severity)
@@ -306,7 +310,7 @@
 		playsound(loc, open_sound, 50, 1)
 		connect()
 	add_fingerprint(user)
-	update()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/crematorium/attackby(P as obj, mob/user as mob, params)
 	if(istype(P, /obj/item/pen))
@@ -327,7 +331,7 @@
 	var/turf/T = get_step(src, SOUTH)
 	if(T.contents.Find(connected))
 		connected.connected = src
-		update()
+		update_icon(UPDATE_OVERLAYS)
 		for(var/atom/movable/A in src)
 			A.forceMove(connected.loc)
 		connected.icon_state = "crema_tray"
@@ -349,7 +353,7 @@
 
 		cremating = TRUE
 		locked = TRUE
-		update()
+		update_icon(UPDATE_OVERLAYS)
 
 		for(var/mob/living/M in search_contents_for(/mob/living))
 			if(QDELETED(M))
@@ -371,7 +375,7 @@
 		sleep(30)
 		cremating = FALSE
 		locked = FALSE
-		update()
+		update_icon(UPDATE_OVERLAYS)
 		playsound(loc, 'sound/machines/ding.ogg', 50, 1)
 	return
 
@@ -419,7 +423,7 @@
 				A.forceMove(connected)
 			//Foreach goto(26)
 		connected.connected = null
-		connected.update()
+		connected.update_icon(UPDATE_OVERLAYS)
 		add_fingerprint(user)
 		qdel(src)
 		return
@@ -488,7 +492,7 @@
 		if(istype(C)) //We found our corpse, is it inside a morgue?
 			morgue = get(C.loc, /obj/structure/morgue)
 			if(morgue)
-				morgue.update()
+				morgue.update_icon(UPDATE_OVERLAYS)
 
 #undef EXTENDED_TRAY
 #undef EMPTY_MORGUE

code/game/objects/structures/safe.dm

@@ -112,7 +112,7 @@ GLOBAL_LIST_EMPTY(safes)
 /obj/structure/safe/examine_status(mob/user)
 	return
 
-/obj/structure/safe/update_icon()
+/obj/structure/safe/update_icon_state()
 	if(open)
 		if(broken)
 			icon_state = "[initial(icon_state)]-open-broken"
@@ -124,17 +124,13 @@ GLOBAL_LIST_EMPTY(safes)
 		else
 			icon_state = initial(icon_state)
 
-	var/list/overlays_to_cut = list(drill_overlay)
-	if(!drill_timer)
-		overlays_to_cut += progress_bar
-
-	cut_overlay(overlays_to_cut)
-
+/obj/structure/safe/update_overlays()
+	. = ..()
 	if(istype(drill, /obj/item/thermal_drill))
 		var/drill_icon = istype(drill, /obj/item/thermal_drill/diamond_drill) ? "d" : "h"
 		var/state = "[initial(icon_state)]_[drill_icon]-drill-[drill_timer ? "on" : "off"]"
 		drill_overlay = image(icon = 'icons/effects/drill.dmi', icon_state = state, pixel_x = drill_x_offset, pixel_y = drill_y_offset)
-		add_overlay(drill_overlay)
+		. += drill_overlay
 
 /obj/structure/safe/attack_ghost(mob/user)
 	if(..() || drill)

code/game/objects/structures/tables_racks.dm

@@ -49,15 +49,15 @@
 /obj/structure/table/proc/deconstruction_hints(mob/user)
 	return "<span class='notice'>The top is <b>screwed</b> on, but the main <b>bolts</b> are also visible.</span>"
 
-/obj/structure/table/update_icon()
+/obj/structure/table/update_icon(updates=ALL)
+	. = ..()
+	update_smoothing()
+
+/obj/structure/table/update_icon_state()
 	if((smoothing_flags & (SMOOTH_CORNERS|SMOOTH_BITMASK)) && !flipped)
 		icon_state = ""
-		QUEUE_SMOOTH(src)
-		QUEUE_SMOOTH_NEIGHBORS(src)
 
 	if(flipped)
-		clear_smooth_overlays()
-
 		var/type = 0
 		var/subtype = null
 		for(var/direction in list(turn(dir,90), turn(dir,-90)) )
@@ -80,7 +80,13 @@
 
 		icon_state = "[base]flip[type][type == 1 ? subtype : ""]"
 
-		return 1
+/obj/structure/table/proc/update_smoothing()
+	if((smoothing_flags & (SMOOTH_CORNERS|SMOOTH_BITMASK)) && !flipped)
+		QUEUE_SMOOTH(src)
+		QUEUE_SMOOTH_NEIGHBORS(src)
+
+	if(flipped)
+		clear_smooth_overlays()
 
 /obj/structure/table/narsie_act()
 	new /obj/structure/table/wood(loc)

code/game/objects/structures/tank_dispenser.dm

@@ -21,7 +21,7 @@
 /obj/structure/dispenser/Initialize(mapload)
 	. = ..()
 	initialize_tanks()
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /obj/structure/dispenser/Destroy()
 	QDEL_LIST(stored_plasma_tanks)
@@ -37,21 +37,21 @@
 		var/obj/item/tank/internals/oxygen/O = new(src)
 		stored_oxygen_tanks.Add(O)
 
-/obj/structure/dispenser/update_icon()
-	cut_overlays()
+/obj/structure/dispenser/update_overlays()
+	. = ..()
 	var/oxy_tank_amount = LAZYLEN(stored_oxygen_tanks)
 	switch(oxy_tank_amount)
 		if(1 to 3)
-			overlays += "oxygen-[oxy_tank_amount]"
+			. += "oxygen-[oxy_tank_amount]"
 		if(4 to INFINITY)
-			overlays += "oxygen-4"
+			. += "oxygen-4"
 
 	var/pla_tank_amount = LAZYLEN(stored_plasma_tanks)
 	switch(pla_tank_amount)
 		if(1 to 4)
-			overlays += "plasma-[pla_tank_amount]"
+			. += "plasma-[pla_tank_amount]"
 		if(5 to INFINITY)
-			overlays += "plasma-5"
+			. += "plasma-5"
 
 /obj/structure/dispenser/attack_hand(mob/user)
 	if(..())
@@ -119,7 +119,7 @@
 		T.forceMove(loc) // If the user's hands are full, place it on the tile of the dispenser.
 
 	to_chat(user, "<span class='notice'>You take [T] out of [src].</span>")
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 
 /// Called when the user clicks on the dispenser with a tank. Tries to insert the tank into the dispenser, and updates the UI if successful.
 /obj/structure/dispenser/proc/try_insert_tank(mob/living/user, list/tank_list, obj/item/tank/T)
@@ -133,7 +133,7 @@
 
 	T.forceMove(src)
 	tank_list.Add(T)
-	update_icon()
+	update_icon(UPDATE_OVERLAYS)
 	to_chat(user, "<span class='notice'>You put [T] in [src].</span>")
 	SStgui.update_uis(src)
 

code/game/objects/structures/watercloset.dm

@@ -47,7 +47,7 @@
 	open = !open
 	update_icon()
 
-/obj/structure/toilet/update_icon()
+/obj/structure/toilet/update_icon_state()
 	icon_state = "toilet[open][cistern]"
 	if(!anchored)
 		pixel_x = 0
@@ -340,11 +340,11 @@
 		transfer_prints_to(S, TRUE)
 		qdel(src)
 
-/obj/machinery/shower/update_icon()
-	cut_overlays()
+/obj/machinery/shower/update_overlays()
+	. = ..()
 	if(on)
 		var/mutable_appearance/water_falling = mutable_appearance('icons/obj/watercloset.dmi', "water", ABOVE_MOB_LAYER)
-		add_overlay(water_falling)
+		. += water_falling
 
 /obj/machinery/shower/proc/handle_mist()
 	// If there is no mist, and the shower was turned on (on a non-freezing temp): make mist in 5 seconds
@@ -565,8 +565,7 @@
 			dir = dir_choices[selected]
 	update_icon()	//is this necessary? probably not
 
-/obj/structure/sink/update_icon()
-	..()
+/obj/structure/sink/update_icon_state()
 	layer = OBJ_LAYER
 	if(!anchored)
 		pixel_x = 0

code/game/objects/structures/windoor_assembly.dm

@@ -50,7 +50,7 @@
 	setDir(ini_dir)
 	move_update_air(T)
 
-/obj/structure/windoor_assembly/update_icon()
+/obj/structure/windoor_assembly/update_icon_state()
 	icon_state = "[facing]_[secure ? "secure_" : ""]windoor_assembly[state]"
 
 /obj/structure/windoor_assembly/CanPass(atom/movable/mover, turf/target, height=0)
@@ -156,7 +156,7 @@
 				return ..()
 
 	//Update to reflect changes(if applicable)
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/windoor_assembly/crowbar_act(mob/user, obj/item/I)	//Crowbar to complete the assembly, Step 7 complete.
 	if(state != "02")
@@ -244,7 +244,7 @@
 		name = "secure anchored windoor assembly"
 	else
 		name = "anchored windoor assembly"
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/windoor_assembly/wrench_act(mob/user, obj/item/I)
 	if(state != "01")
@@ -282,7 +282,7 @@
 			name = "secure windoor assembly"
 		else
 			name = "windoor assembly"
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 
 /obj/structure/windoor_assembly/welder_act(mob/user, obj/item/I)
 	if(state != "01")
@@ -320,7 +320,7 @@
 	setDir(target_dir)
 
 	ini_dir = dir
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	return TRUE
 
 /obj/structure/windoor_assembly/AltClick(mob/user)
@@ -348,5 +348,5 @@
 		facing = "l"
 		to_chat(usr, "The windoor will now slide to the left.")
 
-	update_icon()
+	update_icon(UPDATE_ICON_STATE)
 	return

code/game/objects/structures/window.dm

@@ -454,7 +454,8 @@
 	if(smoothing_flags & (SMOOTH_CORNERS|SMOOTH_BITMASK))
 		QUEUE_SMOOTH_NEIGHBORS(src)
 
-/obj/structure/window/update_icon()
+/obj/structure/window/update_overlays()
+	. = ..()
 	if(!QDELETED(src))
 		if(!fulltile)
 			return
@@ -464,11 +465,10 @@
 		if(smoothing_flags & (SMOOTH_CORNERS|SMOOTH_BITMASK))
 			QUEUE_SMOOTH(src)
 
-		cut_overlay(crack_overlay)
 		if(ratio > 75)
 			return
 		crack_overlay = mutable_appearance('icons/obj/structures.dmi', "damage[ratio]", -(layer+0.1))
-		add_overlay(crack_overlay)
+		. += crack_overlay
 
 /obj/structure/window/temperature_expose(datum/gas_mixture/air, exposed_temperature, exposed_volume)
 	..()
@@ -569,7 +569,7 @@
 	if(active && !powered(power_channel))
 		toggle_tint()
 
-/obj/machinery/button/windowtint/update_icon()
+/obj/machinery/button/windowtint/update_icon_state()
 	icon_state = "light[active]"
 
 /obj/structure/window/plasmabasic