Begin, the Lag Wars Have (#21839)

<img width="700" height="848" alt="image"
src="https://github.com/user-attachments/assets/e0db50af-35db-43c7-b78e-6c1ea5ac569c"
/>

you take a tiny little two year LOA and this happens
this PR hits some large lag culprits:
- UpdateOverlays() getting spammed by human/update_icon. This was 0.85%
of server CPU time during the event. Doesn't sound like a whole lot but
it's insane. 99% of it was caused by sloppy duplicate calls of
update_icon in set_dir (as well as update icon itself!). Refactored to
stop that
- Makes Follow menu update manually, which cuts down on the 2.8 million
REF() calls it made during the event. This was ~1% of CPU time including
ui_data as well.
- Gets rid of a bunch of random runtimes and some lighting-related
harddels.
- NanoUIs now clean themselves up when their owner qdels rather than
forcing the owner to do REF(src) and close all matching UIs. saves us
~0.1% server cpu time! wowza!

code/modules/mob/abstract/ghost/ghost.dm

@@ -132,13 +132,12 @@
 	set category = "Ghost"
 	set desc = "Follow and haunt a mob."
 
-	var/datum/tgui_module/follow_menu/GM = new /datum/tgui_module/follow_menu(usr)
-	GM.ui_interact(usr)
+	GLOB.follow_menu.ui_interact(src)
 
 // This is the ghost's follow verb with an argument
 /mob/abstract/ghost/proc/ManualFollow(var/atom/movable/target)
 	if(!target)
-		return
+		return FALSE
 
 	//Stops orbit if there's any; TG doesn't do this, but if you don't it breaks the orbiting reference
 	//if you are jumping from one mob to another, hence why we're doing it here
@@ -154,6 +153,7 @@
 
 	to_chat(src, SPAN_NOTICE("Now following \the <b>[target]</b>."))
 	update_sight()
+	return TRUE
 
 /mob/abstract/ghost/proc/update_sight()
 	//if they are on a restricted level, then set the ghost vision for them.

code/modules/mob/living/carbon/human/death.dm

@@ -109,9 +109,9 @@
 
 	var/datum/sprite_accessory/hair/hair = GLOB.hair_styles_list[h_style]
 	var/datum/sprite_accessory/facial_hair/facial = GLOB.facial_hair_styles_list[f_style]
-	if(!facial.keep_as_skeleton && f_style)
+	if(facial && !facial.keep_as_skeleton)
 		f_style = "Shaved"
-	if(!hair.keep_as_skeleton && h_style)
+	if(hair && !hair.keep_as_skeleton)
 		h_style = "Bald"
 	update_hair(0)
 

code/modules/mob/living/carbon/human/human.dm

@@ -1466,7 +1466,7 @@
 		self = 1
 
 	if ((src.species.flags & NO_BLOOD) || (status_flags & FAKEDEATH))
-		to_chat(usr, SPAN_WARNING(self ? "You have no pulse." : "[src] has no pulse!"))
+		to_chat(usr, SPAN_WARNING("[self ? "You have" : "[src] has"] no pulse!"))
 		return
 
 	if(!self)

code/modules/mob/living/carbon/human/human_defines.dm

@@ -38,7 +38,6 @@
 
 	var/size_multiplier = 1 //multiplier for the mob's icon size
 	var/damage_multiplier = 1 //multiplies melee combat damage
-	var/icon_update = 1 //whether icon updating shall take place
 
 	var/default_lighting_alpha = LIGHTING_PLANE_ALPHA_VISIBLE
 

code/modules/mob/living/carbon/human/human_movement.dm

@@ -122,9 +122,9 @@
 /mob/living/carbon/human/set_dir(var/new_dir, ignore_facing_dir = FALSE)
 	. = ..()
 	if(. && tail_style)
-		update_tail_showing(1)
+		update_tail_showing(!lying)
 	if(lying)
-		update_icon(forceDirUpdate = TRUE)
+		update_icon(TRUE)
 
 /mob/living/carbon/human/Move()
 	. = ..()

code/modules/mob/living/carbon/human/species/species.dm

@@ -995,7 +995,9 @@
 /datum/species/proc/handle_stance_damage(var/mob/living/carbon/human/H, var/damage_only = FALSE)
 	var/static/support_limbs = list(
 		BP_L_LEG = BP_R_LEG,
-		BP_L_FOOT = BP_R_FOOT
+		BP_L_FOOT = BP_R_FOOT,
+		BP_R_LEG = BP_L_LEG,
+		BP_R_FOOT = BP_L_FOOT
 	)
 
 	var/has_opposite_limb = FALSE

code/modules/mob/living/carbon/human/update_icons.dm

@@ -104,26 +104,29 @@ There are several things that need to be remembered:
 	var/list/overlays_raw[TOTAL_LAYERS] // Our set of "raw" overlays that can be modified, but cannot be directly applied to the mob without preprocessing.
 	var/previous_damage_appearance // store what the body last looked like, so we only have to update it if something changed
 
-#define UPDATE_ICON_IGNORE_DIRECTION_UPDATE -1
-
 // Updates overlays from overlays_raw.
 /mob/living/carbon/human/update_icon(var/forceDirUpdate = FALSE)
 	if (QDELETED(src))
 		return	// No point.
 
+	var/update_lying = (lying_prev != lying) || forceDirUpdate || size_multiplier != 1
+	var/draw_specific_icon = (!lying || species.prone_icon)
+
+	if(update_lying && draw_specific_icon)
+		update_inv_l_hand(FALSE)
+		update_inv_r_hand(FALSE)
+
 	update_hud()		//TODO: remove the need for this
-	ClearOverlays()
 
 	if(cloaked)
 		icon = 'icons/mob/human.dmi'
 		icon_state = "body_cloaked"
-		AddOverlays(list(overlays_raw[L_HAND_LAYER], overlays_raw[R_HAND_LAYER]))
-
-	else if (icon_update)
+		SetOverlays(list(overlays_raw[L_HAND_LAYER], overlays_raw[R_HAND_LAYER]))
+	else
+		var/list/ovr = list()
 		if (icon != stand_icon)
 			icon = stand_icon
 
-		var/list/ovr = list()
 		// We manually add each element instead of just using Copy() so that lists are appended instead of inserted.
 		for (var/item in overlays_raw)
 			if (item)
@@ -137,18 +140,20 @@ There are several things that need to be remembered:
 			var/icon/aura_overlay = icon(A.icon, icon_state = A.icon_state)
 			ovr += aura_overlay
 
-		AddOverlays(ovr)
-
-	if (((lying_prev != lying) || forceDirUpdate || size_multiplier != 1) && forceDirUpdate != UPDATE_ICON_IGNORE_DIRECTION_UPDATE)
-		if(lying && !species.prone_icon) //Only rotate them if we're not drawing a specific icon for being prone.
-			var/matrix/M = matrix()
+		SetOverlays(ovr)
 
+	if(update_lying) //Only rotate them if we're not drawing a specific icon for being prone.
+		var/matrix/M = matrix()
+		M.Scale(size_multiplier)
+		if(draw_specific_icon)
+			M.Translate(0, 16*(size_multiplier-1))
+			animate(src, transform = M, time = ANIM_LYING_TIME)
+		else
 			switch(src.dir)
 				if(SOUTH,EAST)
 					M.Turn(90)
 				else
 					M.Turn(-90)
-			M.Scale(size_multiplier)
 			M.Translate(1,-6)
 			animate(src, transform = M, time = (forceDirUpdate ? 0 : ANIM_LYING_TIME))
 
@@ -157,15 +162,6 @@ There are several things that need to be remembered:
 			if(istype(src.r_hand, /obj/item/gun) && lying)
 				HeldObjectDirTransform(slot_r_hand, src.dir)
 
-		else
-			update_inv_l_hand(FALSE)
-			update_inv_r_hand(FALSE)
-			update_icon(UPDATE_ICON_IGNORE_DIRECTION_UPDATE)
-			var/matrix/M = matrix()
-			M.Scale(size_multiplier)
-			M.Translate(0, 16*(size_multiplier-1))
-			animate(src, transform = M, time = ANIM_LYING_TIME)
-
 	UpdateOverlays()
 	lying_prev = lying
 
@@ -196,9 +192,7 @@ There are several things that need to be remembered:
 
 	animate(item_image, transform = item_transform)
 	overlays_raw[layer] = item_image
-	update_icon(UPDATE_ICON_IGNORE_DIRECTION_UPDATE)
-
-#undef UPDATE_ICON_IGNORE_DIRECTION_UPDATE
+	update_icon()
 
 //DAMAGE OVERLAYS
 //constructs damage icon for each organ from mask * damage field and saves it in our overlays_raw list (as a list of icons).
@@ -1245,7 +1239,7 @@ There are several things that need to be remembered:
 		overlays_raw[L_HAND_LAYER] = null
 
 	if(update_icons)
-		update_icon(forceDirUpdate = TRUE)
+		update_icon(TRUE)
 
 /mob/living/carbon/human/update_inv_r_hand(update_icons = TRUE)
 	if (QDELETED(src))
@@ -1284,7 +1278,7 @@ There are several things that need to be remembered:
 		overlays_raw[R_HAND_LAYER] = null
 
 	if(update_icons)
-		update_icon(forceDirUpdate = TRUE)
+		update_icon(TRUE)
 
 /mob/living/carbon/human/update_inv_wrists(var/update_icons=1)
 	if (QDELETED(src))
@@ -1389,7 +1383,7 @@ There are several things that need to be remembered:
 	if(species.tail && !(mutations & HUSK) && !(mutations & SKELETON) && !(wear_suit && wear_suit.flags_inv & HIDETAIL))
 		var/icon/tail_s = get_tail_icon()
 		overlays_raw[tail_layer] = image(tail_s, icon_state = "[tail_style]_s")
-		animate_tail_reset()
+		animate_tail_reset(FALSE)
 		update_tail_accessory(FALSE)
 
 	if(update_icons)
@@ -1414,7 +1408,7 @@ There are several things that need to be remembered:
 
 	return tail_icon
 
-/mob/living/carbon/human/proc/set_tail_state(var/mob_state)
+/mob/living/carbon/human/proc/set_tail_state(var/mob_state, var/update = TRUE)
 	if(!tail_style)
 		return
 
@@ -1428,8 +1422,7 @@ There are several things that need to be remembered:
 	if(tail_overlay && species.tail_animation)
 		if(tail_overlay.icon_state != mob_state)
 			tail_overlay.icon_state = mob_state
-			update_tail_accessory()
-			update_icon()
+			update_tail_accessory(update)
 		return tail_overlay
 	return null
 
@@ -1461,11 +1454,11 @@ There are several things that need to be remembered:
 /mob/living/carbon/human/proc/animate_tail_fast()
 	set_tail_state("[tail_style]_loop")
 
-/mob/living/carbon/human/proc/animate_tail_reset()
+/mob/living/carbon/human/proc/animate_tail_reset(var/update = TRUE)
 	if(stat != DEAD && !lying)
-		set_tail_state("[tail_style]_idle")
+		set_tail_state("[tail_style]_idle", update)
 	else
-		set_tail_state("[tail_style]_static")
+		set_tail_state("[tail_style]_static", update)
 
 /mob/living/carbon/human/proc/animate_tail_stop(var/update_icons=1)
 	set_tail_state("[tail_style]_static")

code/modules/nano/modules/follow_menu.dm

@@ -1,3 +1,5 @@
+GLOBAL_DATUM_INIT(follow_menu, /datum/tgui_module/follow_menu, new)
+
 /datum/tgui_module/follow_menu/ui_interact(var/mob/user, var/datum/tgui/ui)
 	ui = SStgui.try_update_ui(user, src, ui)
 	if(!ui)
@@ -14,9 +16,15 @@
 		return
 
 	if(action == "follow_target")
-		ghost.ManualFollow(locate(params["follow_target"]) in GLOB.mob_list)
+		if(!ghost.ManualFollow(locate(params["follow_target"]) in GLOB.mob_list))
+			to_chat(ghost, SPAN_WARNING("Failed to follow selected target. Refreshing mob list..."))
+			return TRUE
 
-/datum/tgui_module/follow_menu/ui_data(mob/user)
+	if(action == "refresh")
+		ui.send_full_update()
+		return TRUE
+
+/datum/tgui_module/follow_menu/ui_static_data(mob/user)
 	var/list/data = list()
 	// Don't worry about this is_mod check being for storytellers as well - all it does is highlight antags in red.
 	var/is_mod = check_rights(R_MOD|R_ADMIN, 0, user) || isstoryteller(user)

code/modules/nano/nanoui.dm

@@ -519,7 +519,7 @@ nanoui is used to open and update nano browser uis
  * @return nothing
  */
 /datum/nanoui/process(update = 0)
-	if (!src_object || !user)
+	if (QDELETED(src_object) || QDELETED(user))
 		close()
 		return
 

code/modules/organs/subtypes/standard.dm

@@ -194,12 +194,11 @@
 
 /obj/item/organ/external/hand/is_malfunctioning()
 	. = ..()
-	if(!.)
-		if(owner.is_mechanical())
-			var/actuator_type = limb_name == BP_L_HAND ? BP_ACTUATORS_LEFT : BP_ACTUATORS_RIGHT
-			var/obj/item/organ/internal/machine/actuators/actuator = owner.internal_organs_by_name[actuator_type]
-			if(!actuator || (actuator.status & ORGAN_DEAD))
-				return TRUE
+	if(!. && owner?.is_mechanical())
+		var/actuator_type = limb_name == BP_L_HAND ? BP_ACTUATORS_LEFT : BP_ACTUATORS_RIGHT
+		var/obj/item/organ/internal/machine/actuators/actuator = owner.internal_organs_by_name[actuator_type]
+		if(!actuator || (actuator.status & ORGAN_DEAD))
+			return TRUE
 
 /obj/item/organ/external/hand/take_damage(brute, burn, damage_flags, used_weapon, list/forbidden_limbs, silent)
 	. = ..()

code/modules/reagents/Chemistry-Reagents/Chemistry-Reagents-Drugs.dm

@@ -312,7 +312,7 @@
 	M.hallucination = max(M.hallucination, drug_strength)
 
 	if(prob(15))
-		to_chat(SPAN_GOOD(pick("The floor is melting...", "Everything is so much brighter! Wow!", "Everything is shifting around you.")))
+		to_chat(M, SPAN_GOOD(pick("The floor is melting...", "Everything is so much brighter! Wow!", "Everything is shifting around you.")))
 
 
 /singleton/reagent/drugs/night_juice

code/modules/shuttles/shuttle_console.dm

@@ -170,6 +170,7 @@
 		"can_force" = shuttle.can_force(),
 		"can_rename_ship" = can_rename_ship,
 		"ship_name" = shuttle.name,
+		"current_location" = shuttle.get_location_name(),
 	)
 
 /obj/machinery/computer/shuttle_control/ui_act(action, params)

code/modules/vehicles/vehicle.dm

@@ -202,15 +202,13 @@
 	if(powered && cell?.charge < charge_use && !organic)
 		return FALSE
 	on = TRUE
-	set_light_range_power_color(initial(light_range))
-	set_light_on(on)
+	set_light(initial(light_range))
 	update_icon()
 	return TRUE
 
 /obj/vehicle/proc/turn_off()
 	on = FALSE
-	set_light_range_power_color(0)
-	set_light_on(on)
+	set_light(0)
 	update_icon()
 
 /obj/vehicle/emag_act(var/remaining_charges, mob/user as mob)