Backports several SSlighting improvements: overlay lighting (#17271)

* Backports SSlighting optimizations

* Overlay lighting, first version compiles

* Change conflicting defines

* Sparks and beams dont count towards lumcount

* Fix rendering

* Various fixes

* Fix errors

* Fix PDA light


1

* a

* Update game_options.txt

* Fix plasmaman helmet

* Fixes

* Glowy changes

Co-authored-by: Jamie D <993128+JamieD1@users.noreply.github.com>

_maps/RandomRuins/SpaceRuins/bigape.dmm

@@ -31,7 +31,7 @@
 /area/ruin/powered)
 "g" = (
 /obj/item/flashlight/lamp/bananalamp{
-	brightness_on = 10
+	light_range = 10
 	},
 /obj/structure/table/wood,
 /obj/structure/fans/tiny/invisible,

code/__DEFINES/layers.dm

@@ -107,8 +107,12 @@
 #define RAD_TEXT_LAYER 15.1
 
 
-#define ABOVE_LIGHTING_PLANE 16
-#define ABOVE_LIGHTING_LAYER 16
+#define O_LIGHTING_VISUAL_PLANE 16
+#define O_LIGHTING_VISUAL_LAYER 16
+#define O_LIGHTING_VISUAL_RENDER_TARGET "O_LIGHT_VISUAL_PLANE"
+
+#define ABOVE_LIGHTING_PLANE 17
+#define ABOVE_LIGHTING_LAYER 17
 #define ABOVE_LIGHTING_RENDER_TARGET "ABOVE_LIGHTING_PLANE"
 
 #define FLOOR_OPENSPACE_PLANE 17

code/__DEFINES/lighting.dm

@@ -1,3 +1,16 @@
+///Object doesn't use any of the light systems. Should be changed to add a light source to the object.
+#define NO_LIGHT_SUPPORT 0
+///Light made with the lighting datums, applying a matrix.
+#define STATIC_LIGHT 1
+///Light made by masking the lighting darkness plane.
+#define MOVABLE_LIGHT 2
+
+///Is a movable light source attached to another movable (its loc), meaning that the lighting component should go one level deeper.
+#define LIGHT_ATTACHED (1<<0)
+
+///This light doesn't affect turf's lumcount calculations. Set to 1<<15 to ignore conflicts
+#define LIGHT_NO_LUMCOUNT (1<<15)
+
 //Bay lighting engine shit, not in /code/modules/lighting because BYOND is being shit about it
 /// frequency, in 1/10ths of a second, of the lighting process
 #define LIGHTING_INTERVAL       5

code/__DEFINES/machines.dm

@@ -1,11 +1,20 @@
-// channel numbers for power
-#define EQUIP			1
-#define LIGHT			2
-#define ENVIRON			3
-#define TOTAL			4	//for total power used only
-#define STATIC_EQUIP 	5
-#define STATIC_LIGHT	6
-#define STATIC_ENVIRON	7
+// These are indexes in a list, and indexes for "dynamic" and static channels should be kept contiguous
+#define AREA_USAGE_EQUIP 1
+#define AREA_USAGE_LIGHT 2
+#define AREA_USAGE_ENVIRON 3
+#define AREA_USAGE_TOTAL 4
+#define AREA_USAGE_STATIC_EQUIP 5
+#define AREA_USAGE_STATIC_LIGHT	6
+#define AREA_USAGE_STATIC_ENVIRON 7
+#define AREA_USAGE_LEN AREA_USAGE_STATIC_ENVIRON // largest idx
+/// Index of the first dynamic usage channel
+#define AREA_USAGE_DYNAMIC_START AREA_USAGE_EQUIP
+/// Index of the last dynamic usage channel
+#define AREA_USAGE_DYNAMIC_END AREA_USAGE_ENVIRON
+/// Index of the first static usage channel
+#define AREA_USAGE_STATIC_START AREA_USAGE_STATIC_EQUIP
+/// Index of the last static usage channel
+#define AREA_USAGE_STATIC_END AREA_USAGE_STATIC_ENVIRON
 
 //Power use
 #define NO_POWER_USE 0

code/__DEFINES/mobs.dm

@@ -381,3 +381,6 @@
 
 ///Define for spawning megafauna instead of a mob for cave gen
 #define SPAWN_MEGAFAUNA "bluh bluh huge boss"
+
+///Swarmer flags
+#define SWARMER_LIGHT_ON (1<<0)

code/_onclick/hud/plane_master.dm

@@ -76,8 +76,9 @@
 
 /atom/movable/screen/plane_master/lighting/Initialize()
 	. = ..()
-	filters += filter(type="alpha", render_source=EMISSIVE_RENDER_TARGET, flags=MASK_INVERSE)
-	filters += filter(type="alpha", render_source=EMISSIVE_UNBLOCKABLE_RENDER_TARGET, flags=MASK_INVERSE)
+	filters += filter(type="alpha", render_source = EMISSIVE_RENDER_TARGET, flags = MASK_INVERSE)
+	filters += filter(type="alpha", render_source = EMISSIVE_UNBLOCKABLE_RENDER_TARGET, flags = MASK_INVERSE)
+	filters += filter(type="alpha", render_source = O_LIGHTING_VISUAL_RENDER_TARGET, flags = MASK_INVERSE)
 
 /**
   * Things placed on this mask the lighting plane. Doesn't render directly.
@@ -155,3 +156,11 @@
 	filters = list()
 	if(istype(mymob) && mymob.client?.prefs?.ambientocclusion)
 		filters += AMBIENT_OCCLUSION
+
+/atom/movable/screen/plane_master/o_light_visual
+	name = "overlight light visual plane master"
+	layer = O_LIGHTING_VISUAL_LAYER
+	plane = O_LIGHTING_VISUAL_PLANE
+	render_target = O_LIGHTING_VISUAL_RENDER_TARGET
+	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
+	blend_mode = BLEND_MULTIPLY

code/controllers/subsystem/lighting.dm

@@ -1,17 +1,16 @@
-GLOBAL_LIST_EMPTY(lighting_update_lights) // List of lighting sources  queued for update.
-GLOBAL_LIST_EMPTY(lighting_update_corners) // List of lighting corners  queued for update.
-GLOBAL_LIST_EMPTY(lighting_update_objects) // List of lighting objects queued for update.
-
 SUBSYSTEM_DEF(lighting)
 	name = "Lighting"
 	wait = 2
 	init_order = INIT_ORDER_LIGHTING
 	flags = SS_TICKER
+	var/static/list/sources_queue = list() // List of lighting sources queued for update.
+	var/static/list/corners_queue = list() // List of lighting corners queued for update.
+	var/static/list/objects_queue = list() // List of lighting objects queued for update.
 
 	loading_points = 6 SECONDS // Yogs -- loading times
 
 /datum/controller/subsystem/lighting/stat_entry(msg)
-	msg = "L:[GLOB.lighting_update_lights.len]|C:[GLOB.lighting_update_corners.len]|O:[GLOB.lighting_update_objects.len]"
+	msg = "L:[length(sources_queue)]|C:[length(corners_queue)]|O:[length(objects_queue)]"
 	return ..()
 
 
@@ -34,9 +33,10 @@ SUBSYSTEM_DEF(lighting)
 	MC_SPLIT_TICK_INIT(3)
 	if(!init_tick_checks)
 		MC_SPLIT_TICK
+	var/list/queue = sources_queue
 	var/i = 0
-	for (i in 1 to GLOB.lighting_update_lights.len)
-		var/datum/light_source/L = GLOB.lighting_update_lights[i]
+	for (i in 1 to length(queue))
+		var/datum/light_source/L = queue[i]
 
 		L.update_corners()
 
@@ -47,31 +47,34 @@ SUBSYSTEM_DEF(lighting)
 		else if (MC_TICK_CHECK)
 			break
 	if (i)
-		GLOB.lighting_update_lights.Cut(1, i+1)
+		queue.Cut(1, i+1)
 		i = 0
 
 	if(!init_tick_checks)
 		MC_SPLIT_TICK
 
-	for (i in 1 to GLOB.lighting_update_corners.len)
-		var/datum/lighting_corner/C = GLOB.lighting_update_corners[i]
+	queue = corners_queue
+	for (i in 1 to length(queue))
+		var/datum/lighting_corner/C = queue[i]
 
+		C.needs_update = FALSE //update_objects() can call qdel if the corner is storing no data
 		C.update_objects()
-		C.needs_update = FALSE
+
 		if(init_tick_checks)
 			CHECK_TICK
 		else if (MC_TICK_CHECK)
 			break
 	if (i)
-		GLOB.lighting_update_corners.Cut(1, i+1)
+		queue.Cut(1, i+1)
 		i = 0
 
 
 	if(!init_tick_checks)
 		MC_SPLIT_TICK
 
-	for (i in 1 to GLOB.lighting_update_objects.len)
-		var/datum/lighting_object/O = GLOB.lighting_update_objects[i]
+	queue = objects_queue
+	for (i in 1 to length(queue))
+		var/datum/lighting_object/O = queue[i]
 
 		if (QDELETED(O))
 			continue
@@ -83,7 +86,7 @@ SUBSYSTEM_DEF(lighting)
 		else if (MC_TICK_CHECK)
 			break
 	if (i)
-		GLOB.lighting_update_objects.Cut(1, i+1)
+		queue.Cut(1, i+1)
 
 
 /datum/controller/subsystem/lighting/Recover()

code/datums/components/overlay_lighting.dm

@@ -0,0 +1,381 @@
+///For switchable lights, is it on and currently emitting light?
+#define LIGHTING_ON (1<<0)
+///Is the parent attached to something else, its loc? Then we need to keep an eye of this.
+#define LIGHTING_ATTACHED (1<<1)
+
+#define GET_PARENT (parent_attached_to || parent)
+
+/**
+  * Movable atom overlay-based lighting component.
+  *
+  * * Component works by applying a visual object to the parent target.
+  *
+  * * The component tracks the parent's loc to determine the current_holder.
+  * * The current_holder is either the parent or its loc, whichever is on a turf. If none, then the current_holder is null and the light is not visible.
+  *
+  * * Lighting works at its base by applying a dark overlay and "cutting" said darkness with light, adding (possibly colored) transparency.
+  * * This component uses the visible_mask visual object to apply said light mask on the darkness.
+  *
+  * * The main limitation of this system is that it uses a limited number of pre-baked geometrical shapes, but for most uses it does the job.
+  *
+  * * Another limitation is for big lights: you only see the light if you see the object emiting it.
+  * * For small objects this is good (you can't see them behind a wall), but for big ones this quickly becomes prety clumsy.
+*/
+/datum/component/overlay_lighting
+	///How far the light reaches, float.
+	var/range = 1
+	///Ceiling of range, integer without decimal entries.
+	var/lumcount_range = 0
+	///How much this light affects the dynamic_lumcount of turfs.
+	var/real_lum_power = 0.5
+	///The lum power being used
+	var/used_lum_power = 0.5
+	///Transparency value.
+	var/set_alpha = 0
+	///For light sources that can be turned on and off.
+	var/overlay_lighting_flags = NONE
+
+	///Cache of the possible light overlays, according to size.
+	var/static/list/light_overlays = list(
+		"32" = 'icons/effects/light_overlays/light_32.dmi',
+		"64" = 'icons/effects/light_overlays/light_64.dmi',
+		"96" = 'icons/effects/light_overlays/light_96.dmi',
+		"128" = 'icons/effects/light_overlays/light_128.dmi',
+		"160" = 'icons/effects/light_overlays/light_160.dmi',
+		"192" = 'icons/effects/light_overlays/light_192.dmi',
+		"224" = 'icons/effects/light_overlays/light_224.dmi',
+		"256" = 'icons/effects/light_overlays/light_256.dmi',
+		"288" = 'icons/effects/light_overlays/light_288.dmi',
+		"320" = 'icons/effects/light_overlays/light_320.dmi',
+		"352" = 'icons/effects/light_overlays/light_352.dmi',
+		)
+
+	///Overlay effect to cut into the darkness and provide light.
+	var/obj/effect/overlay/light_visible/visible_mask
+	///Lazy list to track the turfs being affected by our light, to determine their visibility.
+	var/list/turf/affected_turfs
+	///Movable atom currently holding the light. Parent might be a flashlight, for example, but that might be held by a mob or something else.
+	var/atom/movable/current_holder
+	///Movable atom the parent is attached to. For example, a flashlight into a helmet or gun. We'll need to track the thing the parent is attached to as if it were the parent itself.
+	var/atom/movable/parent_attached_to
+
+
+/datum/component/overlay_lighting/Initialize(_range, _power, _color, starts_on)
+	if(!ismovable(parent))
+		return COMPONENT_INCOMPATIBLE
+
+	var/atom/movable/movable_parent = parent
+	if(movable_parent.light_system != MOVABLE_LIGHT)
+		stack_trace("[type] added to [parent], with [movable_parent.light_system] value for the light_system var. Use [MOVABLE_LIGHT] instead.")
+		return COMPONENT_INCOMPATIBLE
+
+	. = ..()
+
+	visible_mask = new()
+	if(!isnull(_range))
+		movable_parent.set_light_range(_range)
+	set_range(parent, movable_parent.light_range)
+	if(!isnull(_power))
+		movable_parent.set_light_power(_power)
+	set_power(parent, movable_parent.light_power)
+	if(!isnull(_color))
+		movable_parent.set_light_color(_color)
+	set_color(parent, movable_parent.light_color)
+	if(!isnull(starts_on))
+		movable_parent.set_light_on(starts_on)
+
+
+/datum/component/overlay_lighting/RegisterWithParent()
+	. = ..()
+	RegisterSignal(parent, COMSIG_MOVABLE_MOVED, .proc/on_parent_moved)
+	RegisterSignal(parent, COMSIG_ATOM_SET_LIGHT_RANGE, .proc/set_range)
+	RegisterSignal(parent, COMSIG_ATOM_SET_LIGHT_POWER, .proc/set_power)
+	RegisterSignal(parent, COMSIG_ATOM_SET_LIGHT_COLOR, .proc/set_color)
+	RegisterSignal(parent, COMSIG_ATOM_SET_LIGHT_ON, .proc/on_toggle)
+	RegisterSignal(parent, COMSIG_ATOM_SET_LIGHT_FLAGS, .proc/on_light_flags_change)
+	var/atom/movable/movable_parent = parent
+	if(movable_parent.light_flags & LIGHT_ATTACHED)
+		overlay_lighting_flags |= LIGHTING_ATTACHED
+		set_parent_attached_to(ismovable(movable_parent.loc) ? movable_parent.loc : null)
+	if(movable_parent.light_flags & LIGHT_NO_LUMCOUNT)
+		overlay_lighting_flags |= LIGHT_NO_LUMCOUNT
+		set_lum_power(real_lum_power)
+	check_holder()
+	if(movable_parent.light_on)
+		turn_on()
+
+
+/datum/component/overlay_lighting/UnregisterFromParent()
+	overlay_lighting_flags &= ~LIGHTING_ATTACHED
+	set_parent_attached_to(null)
+	set_holder(null)
+	clean_old_turfs()
+	UnregisterSignal(parent, list(
+		COMSIG_MOVABLE_MOVED,
+		COMSIG_ATOM_SET_LIGHT_RANGE,
+		COMSIG_ATOM_SET_LIGHT_POWER,
+		COMSIG_ATOM_SET_LIGHT_COLOR,
+		COMSIG_ATOM_SET_LIGHT_ON,
+		COMSIG_ATOM_SET_LIGHT_FLAGS,
+		))
+	if(overlay_lighting_flags & LIGHTING_ON)
+		turn_off()
+	return ..()
+
+
+/datum/component/overlay_lighting/Destroy()
+	set_parent_attached_to(null)
+	set_holder(null)
+	clean_old_turfs()
+	QDEL_NULL(visible_mask)
+	return ..()
+
+
+///Clears the affected_turfs lazylist, removing from its contents the effects of being near the light.
+/datum/component/overlay_lighting/proc/clean_old_turfs()
+	for(var/turf/lit_turf as anything in affected_turfs)
+		lit_turf.dynamic_lumcount -= used_lum_power
+	affected_turfs = null
+
+
+///Populates the affected_turfs lazylist, adding to its contents the effects of being near the light.
+/datum/component/overlay_lighting/proc/get_new_turfs()
+	if(!current_holder)
+		return
+	for(var/turf/lit_turf in view(lumcount_range, get_turf(current_holder)))
+		lit_turf.dynamic_lumcount += used_lum_power
+		LAZYADD(affected_turfs, lit_turf)
+
+
+///Clears the old affected turfs and populates the new ones.
+/datum/component/overlay_lighting/proc/make_luminosity_update()
+	clean_old_turfs()
+	if(!isturf(current_holder?.loc))
+		return
+	get_new_turfs()
+
+
+///Adds the luminosity and source for the afected movable atoms to keep track of their visibility.
+/datum/component/overlay_lighting/proc/add_dynamic_lumi(atom/movable/affected_movable)
+	LAZYSET(affected_movable.affected_dynamic_lights, src, lumcount_range + 1)
+	affected_movable.vis_contents += visible_mask
+	affected_movable.update_dynamic_luminosity()
+
+
+///Removes the luminosity and source for the afected movable atoms to keep track of their visibility.
+/datum/component/overlay_lighting/proc/remove_dynamic_lumi(atom/movable/affected_movable)
+	LAZYREMOVE(affected_movable.affected_dynamic_lights, src)
+	affected_movable.vis_contents -= visible_mask
+	affected_movable.update_dynamic_luminosity()
+
+
+///Called to change the value of parent_attached_to.
+/datum/component/overlay_lighting/proc/set_parent_attached_to(atom/movable/new_parent_attached_to)
+	if(new_parent_attached_to == parent_attached_to)
+		return
+	. = parent_attached_to
+	parent_attached_to = new_parent_attached_to
+	if(.)
+		var/atom/movable/old_parent_attached_to = .
+		UnregisterSignal(old_parent_attached_to, list(COMSIG_PARENT_QDELETING, COMSIG_MOVABLE_MOVED))
+		if(old_parent_attached_to == current_holder)
+			RegisterSignal(old_parent_attached_to, COMSIG_PARENT_QDELETING, .proc/on_holder_qdel)
+			RegisterSignal(old_parent_attached_to, COMSIG_MOVABLE_MOVED, .proc/on_holder_moved)
+	if(parent_attached_to)
+		if(parent_attached_to == current_holder)
+			UnregisterSignal(current_holder, list(COMSIG_PARENT_QDELETING, COMSIG_MOVABLE_MOVED))
+		RegisterSignal(parent_attached_to, COMSIG_PARENT_QDELETING, .proc/on_parent_attached_to_qdel)
+		RegisterSignal(parent_attached_to, COMSIG_MOVABLE_MOVED, .proc/on_parent_attached_to_moved)
+	check_holder()
+
+
+///Called to change the value of current_holder.
+/datum/component/overlay_lighting/proc/set_holder(atom/movable/new_holder)
+	if(new_holder == current_holder)
+		return
+	if(current_holder)
+		if(current_holder != parent && current_holder != parent_attached_to)
+			UnregisterSignal(current_holder, list(COMSIG_PARENT_QDELETING, COMSIG_MOVABLE_MOVED))
+		if(overlay_lighting_flags & LIGHTING_ON)
+			remove_dynamic_lumi(current_holder)
+	current_holder = new_holder
+	if(new_holder == null)
+		clean_old_turfs()
+		return
+	if(overlay_lighting_flags & LIGHTING_ON)
+		add_dynamic_lumi(new_holder)
+	if(new_holder != parent && new_holder != parent_attached_to)
+		RegisterSignal(new_holder, COMSIG_PARENT_QDELETING, .proc/on_holder_qdel)
+		RegisterSignal(new_holder, COMSIG_MOVABLE_MOVED, .proc/on_holder_moved)
+
+
+///Used to determine the new valid current_holder from the parent's loc.
+/datum/component/overlay_lighting/proc/check_holder()
+	var/atom/movable/movable_parent = GET_PARENT
+	if(isturf(movable_parent.loc))
+		set_holder(movable_parent)
+		return
+	var/atom/inside = movable_parent.loc //Parent's loc
+	if(isnull(inside))
+		set_holder(null)
+		return
+	if(isturf(inside.loc))
+		set_holder(inside)
+		return
+	set_holder(null)
+
+
+///Called when the current_holder is qdeleted, to remove the light effect.
+/datum/component/overlay_lighting/proc/on_holder_qdel(atom/movable/source, force)
+	UnregisterSignal(current_holder, list(COMSIG_PARENT_QDELETING, COMSIG_MOVABLE_MOVED))
+	set_holder(null)
+
+
+///Called when current_holder changes loc.
+/datum/component/overlay_lighting/proc/on_holder_moved(atom/movable/source, OldLoc, Dir, Forced)
+	if(!(overlay_lighting_flags & LIGHTING_ON))
+		return
+	make_luminosity_update()
+
+
+///Called when parent changes loc.
+/datum/component/overlay_lighting/proc/on_parent_moved(atom/movable/source, OldLoc, Dir, Forced)
+	var/atom/movable/movable_parent = parent
+	if(overlay_lighting_flags & LIGHTING_ATTACHED)
+		set_parent_attached_to(ismovable(movable_parent.loc) ? movable_parent.loc : null)
+	check_holder()
+	if(!(overlay_lighting_flags & LIGHTING_ON) || !current_holder)
+		return
+	make_luminosity_update()
+
+
+///Called when the current_holder is qdeleted, to remove the light effect.
+/datum/component/overlay_lighting/proc/on_parent_attached_to_qdel(atom/movable/source, force)
+	UnregisterSignal(parent_attached_to, list(COMSIG_PARENT_QDELETING, COMSIG_MOVABLE_MOVED))
+	if(parent_attached_to == current_holder)
+		set_holder(null)
+	set_parent_attached_to(null)
+
+
+///Called when parent_attached_to changes loc.
+/datum/component/overlay_lighting/proc/on_parent_attached_to_moved(atom/movable/source, OldLoc, Dir, Forced)
+	check_holder()
+	if(!(overlay_lighting_flags & LIGHTING_ON) || !current_holder)
+		return
+	make_luminosity_update()
+
+
+///Changes the range which the light reaches. 0 means no light, 6 is the maximum value.
+/datum/component/overlay_lighting/proc/set_range(atom/source, new_range)
+	if(range == new_range)
+		return
+	if(range == 0)
+		turn_off()
+	range = clamp(CEILING(new_range, 0.5), 1, 6)
+	var/pixel_bounds = ((range - 1) * 64) + 32
+	lumcount_range = CEILING(range, 1)
+	visible_mask.icon = light_overlays["[pixel_bounds]"]
+	if(pixel_bounds == 32)
+		visible_mask.transform = null
+		return
+	var/offset = (pixel_bounds - 32) * 0.5
+	var/matrix/transform = new
+	transform.Translate(-offset, -offset)
+	visible_mask.transform = transform
+	if(overlay_lighting_flags & LIGHTING_ON)
+		make_luminosity_update()
+
+
+///Changes the intensity/brightness of the light by altering the visual object's alpha.
+/datum/component/overlay_lighting/proc/set_power(atom/source, new_power)
+	set_lum_power(new_power >= 0 ? 0.5 : -0.5)
+	set_alpha = min(230, (abs(new_power) * 120) + 30)
+	visible_mask.alpha = set_alpha
+
+
+///Changes the light's color, pretty straightforward.
+/datum/component/overlay_lighting/proc/set_color(atom/source, new_color)
+	visible_mask.color = new_color
+
+
+///Toggles the light on and off.
+/datum/component/overlay_lighting/proc/on_toggle(atom/source, new_value)
+	if(new_value) //Truthy value input, turn on.
+		turn_on()
+		return
+	turn_off() //Falsey value, turn off.
+
+
+///Triggered right before the parent light flags change.
+/datum/component/overlay_lighting/proc/on_light_flags_change(atom/source, new_value)
+	var/atom/movable/movable_parent = parent
+	if(new_value & LIGHT_ATTACHED)
+		if(!(movable_parent.light_flags & LIGHT_ATTACHED)) //Gained the LIGHT_ATTACHED property.
+			overlay_lighting_flags |= LIGHTING_ATTACHED
+			if(ismovable(movable_parent.loc))
+				set_parent_attached_to(movable_parent.loc)
+	else if(movable_parent.light_flags & LIGHT_ATTACHED) //Lost the LIGHT_ATTACHED property.
+		overlay_lighting_flags &= ~LIGHTING_ATTACHED
+		set_parent_attached_to(null)
+	
+	if(new_value & LIGHT_NO_LUMCOUNT)
+		if(!(movable_parent.light_flags & LIGHT_NO_LUMCOUNT)) //Gained the NO_LUMCOUNT property
+			overlay_lighting_flags |= LIGHT_NO_LUMCOUNT
+			//Recalculate affecting
+			set_lum_power(real_lum_power)
+	else if(movable_parent.light_flags & LIGHT_NO_LUMCOUNT)	//Lost the NO_LUMCOUNT property
+		overlay_lighting_flags &= ~LIGHT_NO_LUMCOUNT
+		//Recalculate affecting
+		set_lum_power(real_lum_power)
+
+
+///Toggles the light on.
+/datum/component/overlay_lighting/proc/turn_on()
+	if(overlay_lighting_flags & LIGHTING_ON)
+		return
+	if(current_holder)
+		add_dynamic_lumi(current_holder)
+	overlay_lighting_flags |= LIGHTING_ON
+	get_new_turfs()
+
+
+///Toggles the light off.
+/datum/component/overlay_lighting/proc/turn_off()
+	if(!(overlay_lighting_flags & LIGHTING_ON))
+		return
+	if(current_holder)
+		remove_dynamic_lumi(current_holder)
+	overlay_lighting_flags &= ~LIGHTING_ON
+	clean_old_turfs()
+
+
+///Here we append the behavior associated to changing lum_power.
+/datum/component/overlay_lighting/proc/set_lum_power(new_lum_power)
+	//Get the simulated luminosity count (If we have no lumcount, this is set to 0)
+	var/simulated_lum_power = new_lum_power
+	if(overlay_lighting_flags & LIGHT_NO_LUMCOUNT)
+		simulated_lum_power = 0
+	//The new lum power is the same
+	if(used_lum_power == simulated_lum_power)
+		//This light doesn't affect lumcount, but lum_power must be updated regardless
+		if(new_lum_power != simulated_lum_power)
+			. = real_lum_power
+			real_lum_power = new_lum_power
+		return
+	//Set the return value to the old lum power
+	. = real_lum_power
+	real_lum_power = new_lum_power
+	//Get the old used lum power
+	var/old_lum_power = used_lum_power
+	used_lum_power = simulated_lum_power
+	//Calculate the difference
+	var/difference = old_lum_power - used_lum_power
+	//Apply it to any turf we are affecting
+	for(var/t in affected_turfs)
+		var/turf/lit_turf = t
+		lit_turf.dynamic_lumcount -= difference
+
+
+#undef LIGHTING_ON
+#undef LIGHTING_ATTACHED
+#undef GET_PARENT

code/datums/mutations/body.dm

@@ -194,7 +194,6 @@
 	var/obj/effect/dummy/luminescent_glow/glowth //shamelessly copied from luminescents
 	var/glow = 3.5
 	var/range = 2.5
-	var/color
 	var/current_nullify_timer // For veil yogstation\code\modules\antagonists\shadowling\shadowling_abilities.dm
 	power_coeff = 1
 	conflicts = list(/datum/mutation/human/glow/anti)
@@ -209,16 +208,19 @@
 /datum/mutation/human/glow/modify()
 	if(!glowth)
 		return
-	var/power = GET_MUTATION_POWER(src)
+
+	var/glow_color
+
 	if(owner.dna.features["mcolor"][1] != "#")
 		//if it doesn't start with a pound, it needs that for the color
-		color += "#"
+		glow_color += "#"
 	if(length(owner.dna.features["mcolor"]) < 6)
 		//this atrocity converts shorthand hex rgb back into full hex that's required for light to be given a functional value
-		color += owner.dna.features["mcolor"][1] + owner.dna.features["mcolor"][1] + owner.dna.features["mcolor"][2] + owner.dna.features["mcolor"][2] + owner.dna.features["mcolor"][3] + owner.dna.features["mcolor"][3]
+		glow_color += owner.dna.features["mcolor"][1] + owner.dna.features["mcolor"][1] + owner.dna.features["mcolor"][2] + owner.dna.features["mcolor"][2] + owner.dna.features["mcolor"][3] + owner.dna.features["mcolor"][3]
 	else
-		color += owner.dna.features["mcolor"]
-	glowth.set_light(range * power, glow * power, color)
+		glow_color += owner.dna.features["mcolor"]
+
+	glowth.set_light_range_power_color(range * GET_MUTATION_POWER(src), glow, glow_color)
 
 /datum/mutation/human/glow/on_losing(mob/living/carbon/human/owner)
 	. = ..()

code/game/area/areas.dm

@@ -553,11 +553,11 @@ GLOBAL_LIST_EMPTY(teleportlocs)
 	if(always_unpowered)
 		return 0
 	switch(chan)
-		if(EQUIP)
+		if(AREA_USAGE_EQUIP)
 			return power_equip
-		if(LIGHT)
+		if(AREA_USAGE_LIGHT)
 			return power_light
-		if(ENVIRON)
+		if(AREA_USAGE_ENVIRON)
 			return power_environ
 
 	return 0
@@ -584,19 +584,19 @@ GLOBAL_LIST_EMPTY(teleportlocs)
 /area/proc/usage(chan)
 	var/used = 0
 	switch(chan)
-		if(LIGHT)
+		if(AREA_USAGE_LIGHT)
 			used += used_light
-		if(EQUIP)
+		if(AREA_USAGE_EQUIP)
 			used += used_equip
-		if(ENVIRON)
+		if(AREA_USAGE_ENVIRON)
 			used += used_environ
-		if(TOTAL)
+		if(AREA_USAGE_TOTAL)
 			used += used_light + used_equip + used_environ
-		if(STATIC_EQUIP)
+		if(AREA_USAGE_STATIC_EQUIP)
 			used += static_equip
-		if(STATIC_LIGHT)
+		if(AREA_USAGE_STATIC_LIGHT)
 			used += static_light
-		if(STATIC_ENVIRON)
+		if(AREA_USAGE_STATIC_ENVIRON)
 			used += static_environ
 	return used
 
@@ -604,17 +604,17 @@ GLOBAL_LIST_EMPTY(teleportlocs)
   * Add a static amount of power load to an area
   *
   * Possible channels
-  * *STATIC_EQUIP
-  * *STATIC_LIGHT
-  * *STATIC_ENVIRON
+  * *AREA_USAGE_STATIC_EQUIP
+  * *AREA_USAGE_STATIC_LIGHT
+  * *AREA_USAGE_STATIC_ENVIRON
   */
 /area/proc/addStaticPower(value, powerchannel)
 	switch(powerchannel)
-		if(STATIC_EQUIP)
+		if(AREA_USAGE_STATIC_EQUIP)
 			static_equip += value
-		if(STATIC_LIGHT)
+		if(AREA_USAGE_STATIC_LIGHT)
 			static_light += value
-		if(STATIC_ENVIRON)
+		if(AREA_USAGE_STATIC_ENVIRON)
 			static_environ += value
 
 /**
@@ -633,11 +633,11 @@ GLOBAL_LIST_EMPTY(teleportlocs)
 /area/proc/use_power(amount, chan)
 	amount *= POWER_MOD
 	switch(chan)
-		if(EQUIP)
+		if(AREA_USAGE_EQUIP)
 			used_equip += amount
-		if(LIGHT)
+		if(AREA_USAGE_LIGHT)
 			used_light += amount
-		if(ENVIRON)
+		if(AREA_USAGE_ENVIRON)
 			used_environ += amount
 
 /**

code/game/atoms.dm

@@ -152,7 +152,7 @@
 	if(color)
 		add_atom_colour(color, FIXED_COLOUR_PRIORITY)
 
-	if (light_power && light_range)
+	if (light_system == STATIC_LIGHT && light_power && light_range)
 		update_light()
 
 	if (opacity && isturf(loc))

code/game/atoms_movable.dm

@@ -53,6 +53,11 @@
 	/// The degree of pressure protection that mobs in list/contents have from the external environment, between 0 and 1
 	var/contents_pressure_protection = 0
 
+	///Lazylist to keep track on the sources of illumination.
+	var/list/affected_dynamic_lights
+	///Highest-intensity light affecting us, which determines our visibility.
+	var/affecting_dynamic_lumi = 0
+
 
 /atom/movable/Initialize(mapload)
 	. = ..()
@@ -63,6 +68,9 @@
 			render_target = ref(src)
 			em_block = new(src, render_target)
 			vis_contents += em_block
+	
+	if(light_system == MOVABLE_LIGHT)
+		AddComponent(/datum/component/overlay_lighting)
 
 /atom/movable/Destroy()
 	QDEL_NULL(em_block)

code/game/machinery/_machinery.dm

@@ -21,9 +21,9 @@ Class Variables:
    power_channel (num)
       What channel to draw from when drawing power for power mode
       Possible Values:
-         EQUIP:0 -- Equipment Channel
-         LIGHT:2 -- Lighting Channel
-         ENVIRON:3 -- Environment Channel
+         AREA_USAGE_EQUIP:0 -- Equipment Channel
+         AREA_USAGE_LIGHT:2 -- Lighting Channel
+         AREA_USAGE_ENVIRON:3 -- Environment Channel
 
    component_parts (list)
       A list of component parts of machine used by frame based machines.
@@ -53,11 +53,11 @@ Class Procs:
       Default definition uses 'use_power', 'power_channel', 'active_power_usage',
       'idle_power_usage', 'powered()', and 'use_power()' implement behavior.
 
-   powered(chan = EQUIP)         'modules/power/power.dm'
+   powered(chan = AREA_USAGE_EQUIP)         'modules/power/power.dm'
       Checks to see if area that contains the object has power available for power
       channel given in 'chan'.
 
-   use_power(amount, chan=EQUIP)   'modules/power/power.dm'
+   use_power(amount, chan=AREA_USAGE_EQUIP)   'modules/power/power.dm'
       Deducts 'amount' from the power channel 'chan' of the area that contains the object.
 
    power_change()               'modules/power/power.dm'
@@ -103,8 +103,8 @@ Class Procs:
 		//2 = run auto, use active
 	var/idle_power_usage = 0
 	var/active_power_usage = 0
-	var/power_channel = EQUIP
-		//EQUIP,ENVIRON or LIGHT
+	var/power_channel = AREA_USAGE_EQUIP
+		//AREA_USAGE_EQUIP, AREA_USAGE_ENVIRON or AREA_USAGE_LIGHT
 	var/wire_compatible = FALSE
 
 	var/list/component_parts = null //list of all the parts used to build it, if made from certain kinds of frames.

code/game/machinery/airlock_control.dm

@@ -90,7 +90,7 @@
 	name = "airlock sensor"
 	resistance_flags = FIRE_PROOF
 
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 
 	var/id_tag
 	var/master_tag

code/game/machinery/airlock_cycle_control.dm

@@ -49,7 +49,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 4
 	active_power_usage = 8
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	req_access = list(ACCESS_ATMOSPHERICS)
 	max_integrity = 250
 	integrity_failure = 80

code/game/machinery/buttons.dm

@@ -4,7 +4,7 @@
 	icon = 'icons/obj/stationobjs.dmi'
 	icon_state = "doorctrl"
 	var/skin = "doorctrl"
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	var/obj/item/assembly/device
 	var/obj/item/electronics/airlock/board
 	var/device_type = null

code/game/machinery/cell_charger.dm

@@ -6,7 +6,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 5
 	active_power_usage = 60
-	power_channel = EQUIP
+	power_channel = AREA_USAGE_EQUIP
 	circuit = /obj/item/circuitboard/machine/cell_charger
 	pass_flags = PASSTABLE
 	var/obj/item/stock_parts/cell/charging = null

code/game/machinery/computer/_computer.dm

@@ -9,7 +9,10 @@
 	max_integrity = 200
 	integrity_failure = 100
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 40, ACID = 20)
-	var/brightness_on = 1
+	light_system = STATIC_LIGHT
+	light_range = 2
+	light_power = 1
+	light_on = TRUE
 	var/icon_keyboard = "generic_key"
 	var/icon_screen = "generic"
 	var/clockwork = FALSE
@@ -98,9 +101,9 @@
 	if(!.)
 		return // reduce unneeded light changes
 	if(stat & NOPOWER)
-		set_light(0)
+		set_light(FALSE)
 	else
-		set_light(brightness_on)
+		set_light(TRUE)
 
 /obj/machinery/computer/screwdriver_act(mob/living/user, obj/item/I)
 	if(..())

code/game/machinery/dance_machine.dm

@@ -187,60 +187,28 @@
 	var/turf/cen = get_turf(src)
 	FOR_DVIEW(var/turf/t, 3, get_turf(src),INVISIBILITY_LIGHTING)
 		if(t.x == cen.x && t.y > cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_RED
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_RED)
 			continue
 		if(t.x == cen.x && t.y < cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_PURPLE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_PURPLE)
 			continue
 		if(t.x > cen.x && t.y == cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_YELLOW
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_YELLOW)
 			continue
 		if(t.x < cen.x && t.y == cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_GREEN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_GREEN)
 			continue
 		if((t.x+1 == cen.x && t.y+1 == cen.y) || (t.x+2==cen.x && t.y+2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_ORANGE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_ORANGE)
 			continue
 		if((t.x-1 == cen.x && t.y-1 == cen.y) || (t.x-2==cen.x && t.y-2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_CYAN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_CYAN)
 			continue
 		if((t.x-1 == cen.x && t.y+1 == cen.y) || (t.x-2==cen.x && t.y+2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_BLUEGREEN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_BLUEGREEN)
 			continue
 		if((t.x+1 == cen.x && t.y-1 == cen.y) || (t.x+2==cen.x && t.y-2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_BLUE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_BLUE)
 			continue
 		continue
 	FOR_DVIEW_END
@@ -272,61 +240,80 @@
 		sleep(0.7 SECONDS)
 	if(selection.song_name == "Engineering's Ultimate High-Energy Hustle")
 		sleep(28 SECONDS)
-	for(var/obj/reveal in sparkles)
+	for(var/s in sparkles)
+		var/obj/effect/overlay/sparkles/reveal = s
 		reveal.alpha = 255
 	while(active)
-		for(var/obj/item/flashlight/spotlight/glow in spotlights) // The multiples reflects custom adjustments to each colors after dozens of tests
-			if(QDELETED(src) || !active || QDELETED(glow))
+		for(var/g in spotlights) // The multiples reflects custom adjustments to each colors after dozens of tests
+			var/obj/item/flashlight/spotlight/glow = g
+			if(QDELETED(glow))
+				stack_trace("[glow?.gc_destroyed ? "Qdeleting glow" : "null entry"] found in [src].[gc_destroyed ? " Source qdeleting at the time." : ""]")
 				return
-			if(glow.light_color == LIGHT_COLOR_RED)
-				glow.light_color = LIGHT_COLOR_BLUE
-				glow.light_power = glow.light_power * 1.48
-				glow.light_range = 0
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_BLUE)
-				glow.light_color = LIGHT_COLOR_GREEN
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.light_power = glow.light_power * 2 // Any changes to power must come in pairs to neutralize it for other colors
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_GREEN)
-				glow.light_color = LIGHT_COLOR_ORANGE
-				glow.light_power = glow.light_power * 0.5
-				glow.light_range = 0
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_ORANGE)
-				glow.light_color = LIGHT_COLOR_PURPLE
-				glow.light_power = glow.light_power * 2.27
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_PURPLE)
-				glow.light_color = LIGHT_COLOR_BLUEGREEN
-				glow.light_power = glow.light_power * 0.44
-				glow.light_range = 0
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_BLUEGREEN)
-				glow.light_color = LIGHT_COLOR_YELLOW
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_YELLOW)
-				glow.light_color = LIGHT_COLOR_CYAN
-				glow.light_range = 0
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_CYAN)
-				glow.light_color = LIGHT_COLOR_RED
-				glow.light_power = glow.light_power * 0.68
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
-				continue
+			switch(glow.light_color)
+				if(LIGHT_COLOR_RED)
+					if(glow.even_cycle)
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_BLUE)
+					else
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 1.48, LIGHT_COLOR_BLUE)
+						glow.set_light_on(TRUE)
+				if(LIGHT_COLOR_BLUE)
+					if(glow.even_cycle)
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 2, LIGHT_COLOR_GREEN)
+						glow.set_light_on(TRUE)
+					else
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_GREEN)
+				if(LIGHT_COLOR_GREEN)
+					if(glow.even_cycle)
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_ORANGE)
+					else
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 0.5, LIGHT_COLOR_ORANGE)
+						glow.set_light_on(TRUE)
+				if(LIGHT_COLOR_ORANGE)
+					if(glow.even_cycle)
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 2.27, LIGHT_COLOR_PURPLE)
+						glow.set_light_on(TRUE)
+					else
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_PURPLE)
+				if(LIGHT_COLOR_PURPLE)
+					if(glow.even_cycle)
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_BLUEGREEN)
+					else
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 0.44, LIGHT_COLOR_BLUEGREEN)
+						glow.set_light_on(TRUE)
+				if(LIGHT_COLOR_BLUEGREEN)
+					if(glow.even_cycle)
+						glow.set_light_range(glow.base_light_range * DISCO_INFENO_RANGE)
+						glow.set_light_color(LIGHT_COLOR_YELLOW)
+						glow.set_light_on(TRUE)
+					else
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_YELLOW)
+				if(LIGHT_COLOR_YELLOW)
+					if(glow.even_cycle)
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_CYAN)
+					else
+						glow.set_light_range(glow.base_light_range * DISCO_INFENO_RANGE)
+						glow.set_light_color(LIGHT_COLOR_CYAN)
+						glow.set_light_on(TRUE)
+				if(LIGHT_COLOR_CYAN)
+					if(glow.even_cycle)
+						glow.set_light_range_power_color(glow.base_light_range * DISCO_INFENO_RANGE, glow.light_power * 0.68, LIGHT_COLOR_RED)
+						glow.set_light_on(TRUE)
+					else
+						glow.set_light_on(FALSE)
+						glow.set_light_color(LIGHT_COLOR_RED)
+			glow.even_cycle = !glow.even_cycle
 		if(prob(2))  // Unique effects for the dance floor that show up randomly to mix things up
 			INVOKE_ASYNC(src, .proc/hierofunk)
 		sleep(selection.song_beat)
+		if(QDELETED(src))
+			return
 
 #undef DISCO_INFENO_RANGE
 

code/game/machinery/defibrillator_mount.dm

@@ -9,7 +9,7 @@
 	density = FALSE
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 1
-	power_channel = EQUIP
+	power_channel = AREA_USAGE_EQUIP
 	req_one_access = list(ACCESS_MEDICAL, ACCESS_HEADS, ACCESS_SECURITY) //used to control clamps
 	var/obj/item/defibrillator/defib //this mount's defibrillator
 	var/clamps_locked = FALSE //if true, and a defib is loaded, it can't be removed without unlocking the clamps

code/game/machinery/doors/door.dm

@@ -7,7 +7,7 @@
 	density = TRUE
 	move_resist = MOVE_FORCE_VERY_STRONG
 	layer = OPEN_DOOR_LAYER
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	max_integrity = 350
 	armor = list(MELEE = 30, BULLET = 30, LASER = 20, ENERGY = 20, BOMB = 10, BIO = 100, RAD = 100, FIRE = 80, ACID = 70)
 	CanAtmosPass = ATMOS_PASS_DENSITY

code/game/machinery/doors/ministile.dm

@@ -3,7 +3,7 @@
 	desc = "A mechanical door that permits one-way access to an area."
 	icon = 'icons/obj/objects.dmi'
 	icon_state = "ministile_map"
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	density = TRUE
 	obj_integrity = 150
 	max_integrity = 150

code/game/machinery/doors/turnstile.dm

@@ -3,7 +3,7 @@
 	desc = "A mechanical door that permits one-way access to an area."
 	icon = 'icons/obj/objects.dmi'
 	icon_state = "turnstile_map"
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	density = TRUE
 	obj_integrity = 250
 	max_integrity = 250

code/game/machinery/embedded_controller/access_controller.dm

@@ -5,7 +5,7 @@
 #define CYCLE_INTERIOR	5
 
 /obj/machinery/doorButtons
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 2
 	active_power_usage = 4

code/game/machinery/embedded_controller/airlock_controller.dm

@@ -201,7 +201,7 @@
 	density = FALSE
 
 	frequency = FREQ_AIRLOCK_CONTROL
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 
 	// Setup parameters only
 	var/id_tag
@@ -312,4 +312,4 @@
 </div>
 [state_options]"}
 
-	return output
+	return output

code/game/machinery/embedded_controller/simple_vent_controller.dm

@@ -39,7 +39,7 @@
 	density = FALSE
 
 	frequency = FREQ_ATMOS_CONTROL
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 
 	// Setup parameters only
 	var/airpump_tag

code/game/machinery/fat_sucker.dm

@@ -117,12 +117,12 @@
 		else
 			overlays += "[icon_state]_door_off"
 			if(occupant)
-				if(powered(EQUIP))
+				if(powered(AREA_USAGE_EQUIP))
 					overlays += "[icon_state]_stack"
 					overlays += "[icon_state]_yellow"
 			else
 				overlays += "[icon_state]_red"
-	else if(powered(EQUIP))
+	else if(powered(AREA_USAGE_EQUIP))
 		overlays += "[icon_state]_red"
 	if(panel_open)
 		overlays += "[icon_state]_panel"
@@ -130,7 +130,7 @@
 /obj/machinery/fat_sucker/process(delta_time)
 	if(!processing)
 		return
-	if(!powered(EQUIP) || !occupant || !iscarbon(occupant))
+	if(!powered(AREA_USAGE_EQUIP) || !occupant || !iscarbon(occupant))
 		open_machine()
 		return
 
@@ -151,7 +151,7 @@
 	use_power(500)
 
 /obj/machinery/fat_sucker/proc/start_extracting()
-	if(state_open || !occupant || processing || !powered(EQUIP))
+	if(state_open || !occupant || processing || !powered(AREA_USAGE_EQUIP))
 		return
 	if(iscarbon(occupant))
 		var/mob/living/carbon/C = occupant

code/game/machinery/firealarm.dm

@@ -23,7 +23,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 2
 	active_power_usage = 6
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	resistance_flags = FIRE_PROOF
 
 	light_power = 0

code/game/machinery/flasher.dm

@@ -24,6 +24,9 @@
 	anchored = FALSE
 	base_state = "pflash"
 	density = TRUE
+	light_system = MOVABLE_LIGHT //Used as a flash here.
+	light_range = FLASH_LIGHT_RANGE
+	light_on = FALSE
 
 /obj/machinery/flasher/Initialize(mapload, ndir = 0, built = 0)
 	. = ..() // ..() is EXTREMELY IMPORTANT, never forget to add it
@@ -108,7 +111,9 @@
 
 	playsound(src.loc, 'sound/weapons/flash.ogg', 100, 1)
 	flick("[base_state]_flash", src)
-	flash_lighting_fx(FLASH_LIGHT_RANGE, light_power, light_color)
+	set_light_on(TRUE)
+	addtimer(CALLBACK(src, .proc/flash_end), FLASH_LIGHT_DURATION, TIMER_OVERRIDE|TIMER_UNIQUE)
+
 	last_flash = world.time
 	use_power(1000)
 
@@ -126,6 +131,8 @@
 
 	return 1
 
+/obj/machinery/flasher/proc/flash_end()
+	set_light_on(FALSE)
 
 /obj/machinery/flasher/emp_act(severity)
 	. = ..()

code/game/machinery/harvester.dm

@@ -57,7 +57,7 @@
 		start_harvest()
 
 /obj/machinery/harvester/proc/can_harvest()
-	if(!powered(EQUIP) || state_open || !occupant || !iscarbon(occupant))
+	if(!powered(AREA_USAGE_EQUIP) || state_open || !occupant || !iscarbon(occupant))
 		return
 	var/mob/living/carbon/C = occupant
 	if(!allow_clothing)
@@ -92,7 +92,7 @@
 
 /obj/machinery/harvester/proc/harvest()
 	update_icon()
-	if(!harvesting || state_open || !powered(EQUIP) || !occupant || !iscarbon(occupant))
+	if(!harvesting || state_open || !powered(AREA_USAGE_EQUIP) || !occupant || !iscarbon(occupant))
 		return
 	playsound(src, 'sound/machines/juicer.ogg', 20, 1)
 	var/mob/living/carbon/C = occupant

code/game/machinery/hologram.dm

@@ -427,7 +427,6 @@ obj/machinery/holopad/secure/Initialize()
 		Hologram.layer = FLY_LAYER//Above all the other objects/mobs. Or the vast majority of them.
 		Hologram.setAnchored(TRUE)//So space wind cannot drag it.
 		Hologram.name = "[user.name] (Hologram)"//If someone decides to right click.
-		Hologram.set_light(2)	//hologram lighting
 		move_hologram()
 
 		if(AI)
@@ -465,9 +464,9 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	use_power = total_users > 0 ? ACTIVE_POWER_USE : IDLE_POWER_USE
 	active_power_usage = HOLOPAD_PASSIVE_POWER_USAGE + (HOLOGRAM_POWER_USAGE * total_users)
 	if(total_users || replay_mode)
-		set_light(2)
+		set_light_on(TRUE)
 	else
-		set_light(0)
+		set_light_on(FALSE)
 	update_icon()
 
 /obj/machinery/holopad/update_icon()
@@ -599,7 +598,6 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	Hologram.layer = FLY_LAYER//Above all the other objects/mobs. Or the vast majority of them.
 	Hologram.setAnchored(TRUE)//So space wind cannot drag it.
 	Hologram.name = "[record.caller_name] (Hologram)"//If someone decides to right click.
-	Hologram.set_light(2)	//hologram lighting
 	visible_message(span_notice("A holographic image of [record.caller_name] flickers to life before your eyes!"))
 	return Hologram
 
@@ -701,6 +699,10 @@ For the other part of the code, check silicon say.dm. Particularly robot talk.*/
 	var/mob/living/Impersonation
 	var/datum/holocall/HC
 
+	light_system = MOVABLE_LIGHT
+	light_range = 4
+	light_color = COLOR_CYAN
+
 /obj/effect/overlay/holo_pad_hologram/Destroy()
 	Impersonation = null
 	if(!QDELETED(HC))

code/game/machinery/lightswitch.dm

@@ -4,7 +4,7 @@
 	icon = 'icons/obj/power.dmi'
 	icon_state = "light-p"
 	desc = "Make dark."
-	power_channel = LIGHT
+	power_channel = AREA_USAGE_LIGHT
 
 	light_power = 0
 	light_range = 7

code/game/machinery/porta_turret/portable_turret.dm

@@ -16,7 +16,7 @@
 	idle_power_usage = 50		//when inactive, this turret takes up constant 50 Equipment power
 	active_power_usage = 300	//when active, this turret takes up constant 300 Equipment power
 	req_access = list(ACCESS_SEC_DOORS)
-	power_channel = EQUIP	//drains power from the EQUIPMENT channel
+	power_channel = AREA_USAGE_EQUIP	//drains power from the EQUIPMENT channel
 
 	var/base_icon_state = "standard"
 	var/scan_range = 7

code/game/machinery/sci_bombardment.dm

@@ -28,7 +28,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 500
 	active_power_usage = 5000
-	power_channel = EQUIP
+	power_channel = AREA_USAGE_EQUIP
 	density = TRUE
 	verb_say = "states coldly"
 	var/countdown = 30

code/game/mecha/equipment/tools/other_tools.dm

@@ -280,7 +280,7 @@
 	energy_drain = 0
 	range = 0
 	var/coeff = 100
-	var/list/use_channels = list(EQUIP,ENVIRON,LIGHT)
+	var/list/use_channels = list(AREA_USAGE_EQUIP,AREA_USAGE_ENVIRON,AREA_USAGE_LIGHT)
 	selectable = 0
 
 /obj/item/mecha_parts/mecha_equipment/tesla_energy_relay/Destroy()
@@ -343,7 +343,7 @@
 		var/area/A = get_area(chassis)
 		if(A)
 			var/pow_chan
-			for(var/c in list(EQUIP,ENVIRON,LIGHT))
+			for(var/c in list(AREA_USAGE_EQUIP,AREA_USAGE_ENVIRON,AREA_USAGE_LIGHT))
 				if(A.powered(c))
 					pow_chan = c
 					break

code/game/mecha/equipment/weapons/melee_weapons.dm

@@ -190,6 +190,8 @@
 	structure_damage_mult = 4	//Think obi-wan cutting through a bulkhead with his lightsaber but he's a giant mech with a huge terrifying axe
 	minimum_damage = 40			
 	attack_speed_modifier = 1.5 //Kinda chunky
+	light_system = MOVABLE_LIGHT
+	light_range = 5
 	light_color = LIGHT_COLOR_RED
 
 /obj/item/mecha_parts/mecha_equipment/melee_weapon/sword/energy_axe/cleave_attack()	//Mostly copy-pasted sword cleave code with minor tweaks.
@@ -239,11 +241,11 @@
 
 /obj/item/mecha_parts/mecha_equipment/melee_weapon/sword/energy_axe/on_select()
 	START_PROCESSING(SSobj, src)
-	set_light(5)
+	set_light_on(TRUE)
 
 /obj/item/mecha_parts/mecha_equipment/melee_weapon/sword/energy_axe/on_deselect()
 	STOP_PROCESSING(SSobj, src)
-	set_light(0)	
+	set_light_on(FALSE)	
 
 /obj/item/mecha_parts/mecha_equipment/melee_weapon/rocket_fist	//Passive upgrade weapon when selected, makes your mech punch harder AND faster
 	name = "\improper DD-2 \"Atom Smasher\" rocket fist"

code/game/mecha/mecha.dm

@@ -22,6 +22,10 @@
 	layer = BELOW_MOB_LAYER//icon draw layer
 	infra_luminosity = 15 //byond implementation is bugged.
 	force = 5
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 6
+	light_on = FALSE
 	flags_1 = HEAR_1
 	var/ruin_mecha = FALSE //if the mecha starts on a ruin, don't automatically give it a tracking beacon to prevent metagaming.
 	var/can_move = 0 //time of next allowed movement
@@ -48,7 +52,6 @@
 	var/list/proc_res = list() //stores proc owners, like proc_res["functionname"] = owner reference
 	var/datum/effect_system/spark_spread/spark_system = new
 	var/lights = FALSE
-	var/lights_power = 6
 	var/last_user_hud = 1 // used to show/hide the mecha hud while preserving previous preference
 	var/completely_disabled = FALSE //stops the mech from doing anything
 	var/omnidirectional_attacks = FALSE //lets mech shoot anywhere, not just in front of it

code/game/mecha/mecha_actions.dm

@@ -114,11 +114,10 @@
 		return
 	chassis.lights = !chassis.lights
 	if(chassis.lights)
-		chassis.set_light(chassis.lights_power)
 		button_icon_state = "mech_lights_on"
 	else
-		chassis.set_light(-chassis.lights_power)
 		button_icon_state = "mech_lights_off"
+	chassis.set_light_on(chassis.lights)
 	chassis.occupant_message("Toggled lights [chassis.lights?"on":"off"].")
 	chassis.log_message("Toggled lights [chassis.lights?"on":"off"].", LOG_MECHA)
 	UpdateButtonIcon()

code/game/mecha/working/clarke.dm

@@ -9,7 +9,7 @@
 	fast_pressure_step_in = 1.25
 	slow_pressure_step_in = 1.8
 	resistance_flags = LAVA_PROOF | FIRE_PROOF | ACID_PROOF
-	lights_power = 7
+	light_power = 7
 	deflect_chance = 10
 	step_energy_drain = 15 //slightly higher energy drain since you movin those wheels FAST
 	armor = list(MELEE = 20, BULLET = 10, LASER = 20, ENERGY = 0, BOMB = 60, BIO = 0, RAD = 70, FIRE = 100, ACID = 100)

code/game/mecha/working/ripley.dm

@@ -6,7 +6,7 @@
 	step_in = 1.5 //Move speed, lower is faster.
 	max_temperature = 20000
 	max_integrity = 200
-	lights_power = 7
+	light_power = 7
 	deflect_chance = 15
 	armor = list(MELEE = 40, BULLET = 20, LASER = 10, ENERGY = 0, BOMB = 40, BIO = 0, RAD = 20, FIRE = 100, ACID = 100)
 	max_equip = 6
@@ -84,7 +84,7 @@
 	slow_pressure_step_in = 4 //step_in while in normal pressure conditions
 	step_in = 4
 	resistance_flags = LAVA_PROOF | FIRE_PROOF | ACID_PROOF
-	lights_power = 7
+	light_power = 7
 	armor = list(MELEE = 40, BULLET = 30, LASER = 30, ENERGY = 30, BOMB = 60, BIO = 100, RAD = 70, FIRE = 100, ACID = 100)
 	max_equip = 5 // More armor, less tools
 	wreckage = /obj/structure/mecha_wreckage/ripley/firefighter
@@ -103,7 +103,7 @@
 	step_in = 4
 	slow_pressure_step_in = 3
 	opacity=0
-	lights_power = 7
+	light_power = 7
 	wreckage = /obj/structure/mecha_wreckage/ripley/deathripley
 	step_energy_drain = 0
 	enclosed = TRUE

code/game/movable_luminosity.dm

@@ -0,0 +1,19 @@
+///Keeps track of the sources of dynamic luminosity and updates our visibility with the highest.
+/atom/movable/proc/update_dynamic_luminosity()
+	var/highest = 0
+	for(var/i in affected_dynamic_lights)
+		if(affected_dynamic_lights[i] <= highest)
+			continue
+		highest = affected_dynamic_lights[i]
+	if(highest == affecting_dynamic_lumi)
+		return
+	luminosity -= affecting_dynamic_lumi
+	affecting_dynamic_lumi = highest
+	luminosity += affecting_dynamic_lumi
+
+
+///Helper to change several lighting overlay settings.
+/atom/movable/proc/set_light_range_power_color(range, power, color)
+	set_light_range(range)
+	set_light_power(power)
+	set_light_color(color)

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

@@ -20,9 +20,11 @@
 	name = "sparks"
 	icon_state = "sparks"
 	anchored = TRUE
-	light_power = 1.3
-	light_range = MINIMUM_USEFUL_LIGHT_RANGE
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 0.5
 	light_color = LIGHT_COLOR_FIRE
+	light_flags = LIGHT_NO_LUMCOUNT
 
 /obj/effect/particle_effect/sparks/Initialize()
 	..()

code/game/objects/effects/misc.dm

@@ -75,12 +75,18 @@
 	desc = "Tell a coder if you're seeing this."
 	icon_state = "nothing"
 	light_color = "#FFFFFF"
+	light_system = MOVABLE_LIGHT
 	light_range = MINIMUM_USEFUL_LIGHT_RANGE
 	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
 
-/obj/effect/dummy/lighting_obj/Initialize(mapload, _color, _range, _power, _duration)
+/obj/effect/dummy/lighting_obj/Initialize(mapload, _range, _power, _color, _duration)
 	. = ..()
-	set_light(_range ? _range : light_range, _power ? _power : light_power, _color ? _color : light_color)
+	if(!isnull(_range))
+		set_light_range(_range)
+	if(!isnull(_power))
+		set_light_power(_power)
+	if(!isnull(_color))
+		set_light_color(_color)
 	if(_duration)
 		QDEL_IN(src, _duration)
 

code/game/objects/effects/overlays.dm

@@ -77,3 +77,14 @@
 	layer = FLOAT_LAYER
 	vis_flags = VIS_INHERIT_ID
 	appearance_flags = KEEP_TOGETHER | LONG_GLIDE | PIXEL_SCALE
+
+/obj/effect/overlay/light_visible
+	name = ""
+	icon = 'icons/effects/light_overlays/light_32.dmi'
+	icon_state = "light"
+	layer = O_LIGHTING_VISUAL_LAYER
+	plane = O_LIGHTING_VISUAL_PLANE
+	appearance_flags = RESET_COLOR | RESET_ALPHA | RESET_TRANSFORM
+	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
+	alpha = 0
+	vis_flags = NONE

code/game/objects/items/candle.dm

@@ -1,4 +1,5 @@
 #define CANDLE_LUMINOSITY	2
+
 /obj/item/candle
 	name = "red candle"
 	desc = "In Greek myth, Prometheus stole fire from the Gods and gave it to \
@@ -7,7 +8,10 @@
 	icon_state = "candle1"
 	item_state = "candle1"
 	w_class = WEIGHT_CLASS_TINY
+	light_system = MOVABLE_LIGHT
+	light_range = CANDLE_LUMINOSITY
 	light_color = LIGHT_COLOR_FIRE
+	light_on = FALSE
 	heat = 1000
 	var/wax = 2000
 	var/lit = FALSE
@@ -43,7 +47,7 @@
 		lit = TRUE
 		if(show_message)
 			usr.visible_message(show_message)
-		set_light(CANDLE_LUMINOSITY)
+		set_light_on(TRUE)
 		START_PROCESSING(SSobj, src)
 		update_icon()
 
@@ -52,7 +56,7 @@
 		return
 	lit = FALSE
 	update_icon()
-	set_light(0)
+	set_light_on(FALSE)
 	return TRUE
 
 /obj/item/candle/extinguish()

code/game/objects/items/cigs_lighters.dm

@@ -542,6 +542,10 @@ CIGARETTE PACKETS ARE IN FANCY.DM
 	w_class = WEIGHT_CLASS_TINY
 	flags_1 = CONDUCT_1
 	slot_flags = ITEM_SLOT_BELT
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 0.6
+	light_on = FALSE
 	var/lit = 0
 	var/fancy = TRUE
 	var/overlay_state
@@ -588,20 +592,21 @@ CIGARETTE PACKETS ARE IN FANCY.DM
 		playsound(src, 'sound/items/lighter/light.ogg', 50, 2)
 
 /obj/item/lighter/proc/set_lit(new_lit)
+	if(lit == new_lit)
+		return
 	lit = new_lit
 	if(lit)
 		force = 5
 		damtype = BURN
 		hitsound = 'sound/items/welder.ogg'
 		attack_verb = list("burnt", "singed")
-		set_light(1)
 		START_PROCESSING(SSobj, src)
 	else
 		hitsound = "swing_hit"
 		force = 0
 		attack_verb = null //human_defense.dm takes care of it
-		set_light(0)
 		STOP_PROCESSING(SSobj, src)
+	set_light_on(lit)
 	update_icon()
 
 /obj/item/lighter/extinguish()

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

@@ -40,7 +40,11 @@ GLOBAL_LIST_EMPTY(PDAs)
 	slot_flags = ITEM_SLOT_ID | ITEM_SLOT_BELT
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 100, ACID = 100)
 	resistance_flags = FIRE_PROOF | ACID_PROOF
-
+	light_system = MOVABLE_LIGHT
+	light_range = 2.3
+	light_power = 0.6
+	light_color = "#FFCC66"
+	light_on = FALSE
 
 	//Main variables
 	var/owner = null // String name of owner
@@ -63,8 +67,6 @@ GLOBAL_LIST_EMPTY(PDAs)
 
 	//Secondary variables
 	var/scanmode = PDA_SCANNER_NONE
-	var/fon = FALSE //Is the flashlight function on?
-	var/f_lum = 2.3 //Luminosity for the flashlight function
 	var/silent = FALSE //To beep or not to beep, that is the question
 	var/toff = FALSE //If TRUE, messenger disabled
 	var/list/tnote = list() //Current list of received signals, which are transmuted into messages on-the-spot. Can also be just plain strings, y'know, like, who really gives a shit, y'know
@@ -119,8 +121,6 @@ GLOBAL_LIST_EMPTY(PDAs)
 
 /obj/item/pda/Initialize()
 	. = ..()
-	if(fon)
-		set_light(f_lum)
 
 	GLOB.PDAs += src
 	if(default_cartridge)
@@ -207,7 +207,7 @@ GLOBAL_LIST_EMPTY(PDAs)
 	if(inserted_item)
 		overlay.icon_state = "insert_overlay"
 		add_overlay(new /mutable_appearance(overlay))
-	if(fon)
+	if(light_on)
 		overlay.icon_state = "light_overlay"
 		add_overlay(new /mutable_appearance(overlay))
 	if(pai)
@@ -345,7 +345,7 @@ GLOBAL_LIST_EMPTY(PDAs)
 				if(id && id.registered_account && id.registered_account.account_job.paycheck_department)
 					dat += "<li><a href='byond://?src=[REF(src)];choice=6'>[PDAIMG(notes)]Show Department Goals</a></li>"
 				dat += "<li><a href='byond://?src=[REF(src)];choice=3'>[PDAIMG(atmos)]Atmospheric Scan</a></li>"
-				dat += "<li><a href='byond://?src=[REF(src)];choice=Light'>[PDAIMG(flashlight)][fon ? "Disable" : "Enable"] Flashlight</a></li>"
+				dat += "<li><a href='byond://?src=[REF(src)];choice=Light'>[PDAIMG(flashlight)][light_on ? "Disable" : "Enable"] Flashlight</a></li>"
 				if (pai)
 					if(pai.loc != src)
 						pai = null
@@ -945,13 +945,14 @@ GLOBAL_LIST_EMPTY(PDAs)
 /obj/item/pda/proc/toggle_light()
 	if(issilicon(usr) || !usr.canUseTopic(src, BE_CLOSE))
 		return
-	if(fon)
-		fon = FALSE
-		set_light(0)
-	else if(f_lum)
-		fon = TRUE
-		set_light(f_lum)
+	if(light_on)
+		set_light_on(FALSE)
+	else if(light_range)
+		set_light_on(TRUE)
 	update_icon()
+	for(var/X in actions)
+		var/datum/action/A = X
+		A.UpdateButtonIcon()
 
 /obj/item/pda/proc/remove_pen()
 

code/game/objects/items/devices/PDA/PDA_types.dm

@@ -21,7 +21,6 @@
 /obj/item/pda/ai
 	icon = null
 	ttone = "data"
-	fon = FALSE
 
 /obj/item/pda/ai/attack_self(mob/user)
 	if ((honkamt > 0) && (prob(60)))//For clown virus.

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

@@ -12,9 +12,11 @@
 	slot_flags = ITEM_SLOT_BELT
 	materials = list(/datum/material/iron=50, /datum/material/glass=20)
 	actions_types = list(/datum/action/item_action/toggle_light)
+	light_system = MOVABLE_LIGHT
+	light_range = 4
+	light_power = 1
+	light_on = FALSE
 	var/on = FALSE
-	var/brightness_on = 4 //range of light when on
-	var/flashlight_power = 1 //strength of the light when on
 
 /obj/item/flashlight/Initialize()
 	. = ..()
@@ -22,16 +24,14 @@
 		on = TRUE
 	update_brightness()
 
-/obj/item/flashlight/proc/update_brightness(mob/user = null)
+/obj/item/flashlight/proc/update_brightness(mob/user)
 	if(on)
 		icon_state = "[initial(icon_state)]-on"
-		if(flashlight_power)
-			set_light(l_range = brightness_on, l_power = flashlight_power)
-		else
-			set_light(brightness_on)
 	else
 		icon_state = initial(icon_state)
-		set_light(0)
+	set_light_on(on)
+	if(light_system == STATIC_LIGHT)
+		update_light()
 
 /obj/item/flashlight/attack_self(mob/user)
 	on = !on
@@ -67,7 +67,7 @@
 			to_chat(user, span_warning("[M] doesn't have a head!"))
 			return
 
-		if(flashlight_power < 1)
+		if(light_power < 1)
 			to_chat(user, "[span_warning("\The [src] isn't bright enough to see anything!")] ")
 			return
 
@@ -171,7 +171,7 @@
 	icon_state = "penlight"
 	item_state = ""
 	flags_1 = CONDUCT_1
-	brightness_on = 2
+	light_range = 2
 	var/holo_cooldown = 0
 
 /obj/item/flashlight/pen/afterattack(atom/target, mob/user, proximity_flag)
@@ -219,7 +219,7 @@
 	lefthand_file = 'icons/mob/inhands/equipment/security_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/security_righthand.dmi'
 	force = 9 // Not as good as a stun baton.
-	brightness_on = 5 // A little better than the standard flashlight.
+	light_range = 5 // A little better than the standard flashlight.
 	hitsound = 'sound/weapons/genhit1.ogg'
 
 // the desk lamps are a bit special
@@ -231,7 +231,7 @@
 	lefthand_file = 'icons/mob/inhands/items_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/items_righthand.dmi'
 	force = 10
-	brightness_on = 5
+	light_range = 5
 	w_class = WEIGHT_CLASS_BULKY
 	flags_1 = CONDUCT_1
 	materials = list()
@@ -267,7 +267,7 @@
 	name = "flare"
 	desc = "A red Nanotrasen issued flare. There are instructions on the side, it reads 'pull cord, make light'."
 	w_class = WEIGHT_CLASS_SMALL
-	brightness_on = 7 // Pretty bright.
+	light_range = 7 // Pretty bright.
 	icon_state = "flare"
 	item_state = "flare"
 	lefthand_file = 'icons/mob/inhands/items_lefthand.dmi'
@@ -353,7 +353,7 @@
 /obj/item/flashlight/flare/emergency
 	name = "safety flare"
 	desc = "A flare issued to Nanotrasen employees for emergencies. There are instructions on the side, it reads 'pull cord, make light, obey Nanotrasen'."
-	brightness_on = 3
+	light_range = 3
 	item_state = "flare"
 	icon_state = "flaresafety"
 	ignition_sound = 'sound/items/flare_strike_2.ogg'
@@ -363,8 +363,8 @@
 /obj/item/flashlight/flare/signal
 	name = "signalling flare"
 	desc = "A specialized formulation of the standard Nanotrasen-issued flare, containing increased magnesium content. There are instructions on the side, it reads 'pull cord, make intense light'."
-	brightness_on = 5
-	flashlight_power = 2
+	light_range = 5
+	light_power = 2
 	item_state = "flaresignal"
 	icon_state = "flaresignal"
 	light_color = LIGHT_COLOR_HALOGEN
@@ -377,7 +377,7 @@
 	name = "torch"
 	desc = "A torch fashioned from some leaves and a log."
 	w_class = WEIGHT_CLASS_BULKY
-	brightness_on = 4
+	light_range = 4
 	icon_state = "torch"
 	item_state = "torch"
 	lefthand_file = 'icons/mob/inhands/items_lefthand.dmi'
@@ -394,19 +394,19 @@
 	lefthand_file = 'icons/mob/inhands/equipment/mining_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/equipment/mining_righthand.dmi'
 	desc = "A mining lantern."
-	brightness_on = 6			// luminosity when on
+	light_range = 6			// luminosity when on
 
 /obj/item/flashlight/lantern/heirloom_moth
 	name = "old lantern"
 	desc = "An old lantern that has seen plenty of use."
-	brightness_on = 4
+	light_range = 4
 
 /obj/item/flashlight/lantern/syndicate
 	name = "suspicious lantern"
 	desc = "A suspicious looking lantern."
 	icon_state = "syndilantern"
 	item_state = "syndilantern"
-	brightness_on = 10
+	light_range = 10
 
 /obj/item/flashlight/lantern/jade
 	name = "jade lantern"
@@ -424,7 +424,7 @@
 	w_class = WEIGHT_CLASS_SMALL
 	slot_flags = ITEM_SLOT_BELT
 	materials = list()
-	brightness_on = 6 //luminosity when on
+	light_range = 6 //luminosity when on
 
 /obj/item/flashlight/emp
 	var/emp_max_charges = 4
@@ -492,7 +492,7 @@
 	desc = "A military-grade glowstick."
 	custom_price = 10
 	w_class = WEIGHT_CLASS_SMALL
-	brightness_on = 4
+	light_range = 4
 	color = LIGHT_COLOR_GREEN
 	icon_state = "glowstick"
 	item_state = "glowstick"
@@ -500,13 +500,14 @@
 	var/fuel = 0
 
 /obj/item/flashlight/glowstick/Initialize()
-	fuel = rand(3200, 4000)
+	fuel = rand(1600, 2000)
 	light_color = color
+
 	. = ..()
 
 /obj/item/flashlight/glowstick/Destroy()
 	STOP_PROCESSING(SSobj, src)
-	. = ..()
+	return ..()
 
 /obj/item/flashlight/glowstick/process(delta_time)
 	fuel = max(fuel -= delta_time, 0)
@@ -525,13 +526,13 @@
 	if(fuel <= 0)
 		icon_state = "glowstick-empty"
 		cut_overlays()
-		set_light(0)
+		set_light_on(FALSE)
 	else if(on)
 		var/mutable_appearance/glowstick_overlay = mutable_appearance(icon, "glowstick-glow")
 		glowstick_overlay.color = color
 		add_overlay(glowstick_overlay)
 		item_state = "glowstick-on"
-		set_light(brightness_on)
+		set_light_on(TRUE)
 	else
 		icon_state = "glowstick"
 		cut_overlays()
@@ -598,30 +599,52 @@
 	name = "disco light"
 	desc = "Groovy..."
 	icon_state = null
-	light_color = null
-	brightness_on = 0
-	light_range = 0
+	light_range = 4
 	light_power = 10
 	alpha = 0
 	layer = 0
 	on = TRUE
 	anchored = TRUE
-	var/range = null
 	resistance_flags = INDESTRUCTIBLE | LAVA_PROOF | FIRE_PROOF | UNACIDABLE | ACID_PROOF
+	///Boolean that switches when a full color flip ends, so the light can appear in all colors.
+	var/even_cycle = FALSE
+	///Base light_range that can be set on Initialize to use in smooth light range expansions and contractions.
+	var/base_light_range = 4
+
+/obj/item/flashlight/spotlight/Initialize(mapload, _light_range, _light_power, _light_color)
+	. = ..()
+	if(!isnull(_light_range))
+		base_light_range = _light_range
+		set_light_range(_light_range)
+	if(!isnull(_light_power))
+		set_light_power(_light_power)
+	if(!isnull(_light_color))
+		set_light_color(_light_color)
 
 /obj/item/flashlight/flashdark
 	name = "flashdark"
 	desc = "A strange device manufactured with mysterious elements that somehow emits darkness. Or maybe it just sucks in light? Nobody knows for sure."
 	icon_state = "flashdark"
 	item_state = "flashdark"
-	brightness_on = 2.5
-	flashlight_power = -3
+	light_system = STATIC_LIGHT //The overlay light component is not yet ready to produce darkness.
+	light_range = 0
+	///Variable to preserve old lighting behavior in flashlights, to handle darkness.
+	var/dark_light_range = 2.5
+	///Variable to preserve old lighting behavior in flashlights, to handle darkness.
+	var/dark_light_power = -3
+
+/obj/item/flashlight/flashdark/update_brightness(mob/user)
+	. = ..()
+	if(on)
+		set_light(dark_light_range, dark_light_power)
+	else
+		set_light(0)
 
 /obj/item/flashlight/eyelight
 	name = "eyelight"
 	desc = "This shouldn't exist outside of someone's head, how are you seeing this?"
-	brightness_on = 15
-	flashlight_power = 1
+	light_range = 15
+	light_power = 1
 	flags_1 = CONDUCT_1
 	item_flags = DROPDEL
 	actions_types = list()

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

@@ -130,7 +130,7 @@
 		if(!A || emped)
 			on = FALSE
 		else
-			on = A.powered(EQUIP) // set "on" to the power status
+			on = A.powered(AREA_USAGE_EQUIP) // set "on" to the power status
 
 		if(!on)
 			icon_state = "intercom-p"

code/game/objects/items/discoball.dm

@@ -67,7 +67,7 @@
 /obj/structure/discoball/proc/DiscoFever()
 	remove_atom_colour(TEMPORARY_COLOUR_PRIORITY)
 	current_color = random_color()
-	set_light(range, power, current_color)
+	set_light_color(current_color)
 	add_atom_colour("#[current_color]", FIXED_COLOUR_PRIORITY)
 	update_icon()
 	TimerID = addtimer(CALLBACK(src, .proc/DiscoFever), 5, TIMER_STOPPABLE)  //Call ourselves every 0.5 seconds to change colors
@@ -100,60 +100,28 @@
 	var/turf/cen = get_turf(src)
 	FOR_DVIEW(var/turf/t, 3, get_turf(src),INVISIBILITY_LIGHTING)
 		if(t.x == cen.x && t.y > cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_RED
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_RED)
 			continue
 		if(t.x == cen.x && t.y < cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_PURPLE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_PURPLE)
 			continue
 		if(t.x > cen.x && t.y == cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_YELLOW
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_YELLOW)
 			continue
 		if(t.x < cen.x && t.y == cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_GREEN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_GREEN)
 			continue
 		if((t.x+1 == cen.x && t.y+1 == cen.y) || (t.x+2==cen.x && t.y+2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_ORANGE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_ORANGE)
 			continue
 		if((t.x-1 == cen.x && t.y-1 == cen.y) || (t.x-2==cen.x && t.y-2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_CYAN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_CYAN)
 			continue
 		if((t.x-1 == cen.x && t.y+1 == cen.y) || (t.x-2==cen.x && t.y+2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_BLUEGREEN
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_BLUEGREEN)
 			continue
 		if((t.x+1 == cen.x && t.y-1 == cen.y) || (t.x+2==cen.x && t.y-2 == cen.y))
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.light_color = LIGHT_COLOR_BLUE
-			L.light_power = 30-(get_dist(src,L)*8)
-			L.range = 1.4+get_dist(src, L)
-			spotlights+=L
+			spotlights += new /obj/item/flashlight/spotlight(t, 1.4 + get_dist(src, t), 30 - (get_dist(src, t) * 8), LIGHT_COLOR_BLUE)
 			continue
 		continue
 	FOR_DVIEW_END
@@ -183,57 +151,38 @@
 				S.pixel_y = 7
 				S.forceMove(get_turf(src))
 		sleep(0.7 SECONDS)
-	for(var/obj/reveal in sparkles)
+	for(var/s in sparkles)
+		var/obj/effect/overlay/sparkles/reveal = s
 		reveal.alpha = 255
 	while(TurnedOn)
-		for(var/obj/item/flashlight/spotlight/glow in spotlights) // The multiples reflects custom adjustments to each colors after dozens of tests
-			if(QDELETED(src) || !TurnedOn || QDELETED(glow))
+		for(var/g in spotlights) // The multiples reflects custom adjustments to each colors after dozens of tests
+			var/obj/item/flashlight/spotlight/glow = g
+			if(QDELETED(glow))
+				stack_trace("[glow?.gc_destroyed ? "Qdeleting glow" : "null entry"] found in [src].[gc_destroyed ? " Source qdeleting at the time." : ""]")
 				return
 			if(glow.light_color == LIGHT_COLOR_RED)
-				glow.light_color = LIGHT_COLOR_BLUE
-				glow.light_power = glow.light_power * 1.48
-				glow.light_range = 0
-				glow.update_light()
+				glow.set_light_range_power_color(0, glow.light_power * 1.48, LIGHT_COLOR_BLUE)
 				continue
 			if(glow.light_color == LIGHT_COLOR_BLUE)
-				glow.light_color = LIGHT_COLOR_GREEN
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.light_power = glow.light_power * 2 // Any changes to power must come in pairs to neutralize it for other colors
-				glow.update_light()
+				glow.set_light_range_power_color(glow.light_range * DISCO_INFENO_RANGE, glow.light_power * 2, LIGHT_COLOR_GREEN)
 				continue
 			if(glow.light_color == LIGHT_COLOR_GREEN)
-				glow.light_color = LIGHT_COLOR_ORANGE
-				glow.light_power = glow.light_power * 0.5
-				glow.light_range = 0
-				glow.update_light()
+				glow.set_light_range_power_color(0, glow.light_power * 0.5, LIGHT_COLOR_ORANGE)
 				continue
 			if(glow.light_color == LIGHT_COLOR_ORANGE)
-				glow.light_color = LIGHT_COLOR_PURPLE
-				glow.light_power = glow.light_power * 2.27
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
+				glow.set_light_range_power_color(glow.light_range * DISCO_INFENO_RANGE, glow.light_power * 2.27, LIGHT_COLOR_PURPLE)
 				continue
 			if(glow.light_color == LIGHT_COLOR_PURPLE)
-				glow.light_color = LIGHT_COLOR_BLUEGREEN
-				glow.light_power = glow.light_power * 0.44
-				glow.light_range = 0
-				glow.update_light()
+				glow.set_light_range_power_color(0, glow.light_power * 0.44, LIGHT_COLOR_BLUEGREEN)
 				continue
 			if(glow.light_color == LIGHT_COLOR_BLUEGREEN)
-				glow.light_color = LIGHT_COLOR_YELLOW
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
+				glow.set_light_range_power_color(glow.light_range * DISCO_INFENO_RANGE, glow.light_power, LIGHT_COLOR_YELLOW)
 				continue
 			if(glow.light_color == LIGHT_COLOR_YELLOW)
-				glow.light_color = LIGHT_COLOR_CYAN
-				glow.light_range = 0
-				glow.update_light()
+				glow.set_light_range_power_color(0, glow.light_power, LIGHT_COLOR_CYAN)
 				continue
 			if(glow.light_color == LIGHT_COLOR_CYAN)
-				glow.light_color = LIGHT_COLOR_RED
-				glow.light_power = glow.light_power * 0.68
-				glow.light_range = glow.range * DISCO_INFENO_RANGE
-				glow.update_light()
+				glow.set_light_range_power_color(glow.light_range * DISCO_INFENO_RANGE, glow.light_power * 0.68, LIGHT_COLOR_RED)
 				continue
 		if(prob(2))  // Unique effects for the dance floor that show up randomly to mix things up
 			INVOKE_ASYNC(src, .proc/hierofunk)

code/game/objects/items/flamethrower.dm

@@ -16,6 +16,8 @@
 	w_class = WEIGHT_CLASS_NORMAL
 	materials = list(/datum/material/iron=500)
 	resistance_flags = FIRE_PROOF
+	light_system = MOVABLE_LIGHT
+	light_on = FALSE
 	var/status = FALSE
 	var/lit = FALSE	//on or off
 	light_color = LIGHT_COLOR_FIRE
@@ -175,6 +177,7 @@
 		set_light(0)
 		playsound(loc, deac_sound, 50, TRUE)
 		STOP_PROCESSING(SSobj,src)
+	set_light_on(lit)
 	update_icon()
 
 /obj/item/flamethrower/CheckParts(list/parts_list)

code/game/objects/items/grenades/flashbang.dm

@@ -13,7 +13,7 @@
 		return
 	do_sparks(rand(5, 9), FALSE, src)
 	playsound(flashbang_turf, 'sound/weapons/flashbang.ogg', 100, TRUE, 8, 0.9)
-	new /obj/effect/dummy/lighting_obj (flashbang_turf, LIGHT_COLOR_WHITE, (flashbang_range + 2), 4, 2)
+	new /obj/effect/dummy/lighting_obj (flashbang_turf, flashbang_range + 2, 4, COLOR_WHITE, 2)
 	for(var/mob/living/M in get_hearers_in_view(flashbang_range, flashbang_turf))
 		bang(get_turf(M), M)
 	qdel(src)

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

@@ -5,13 +5,15 @@
 	max_integrity = 200
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 100, ACID = 30)
 	resistance_flags = FIRE_PROOF
-	var/brightness_on = 3
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 1
+	light_on = FALSE
 	var/saber_color = null
 
 /obj/item/melee/transforming/energy/Initialize()
 	. = ..()
 	if(active)
-		set_light(brightness_on)
 		START_PROCESSING(SSobj, src)
 
 /obj/item/melee/transforming/energy/Destroy()
@@ -40,10 +42,9 @@
 			if(saber_color)
 				icon_state = "sword[saber_color]"
 			START_PROCESSING(SSobj, src)
-			set_light(brightness_on)
 		else
 			STOP_PROCESSING(SSobj, src)
-			set_light(0)
+		set_light_on(active)
 
 /obj/item/melee/transforming/energy/is_hot()
 	return active * heat
@@ -167,7 +168,6 @@
 	if(hacked)
 		var/set_color = pick(possible_colors)
 		light_color = possible_colors[set_color]
-		update_light()
 
 /obj/item/melee/transforming/energy/sword/saber/red
 	possible_colors = list("red" = LIGHT_COLOR_RED)

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

@@ -17,6 +17,10 @@
 	pickup_sound =  'sound/items/handling/weldingtool_pickup.ogg'
 	var/acti_sound = 'sound/items/welderactivate.ogg'
 	var/deac_sound = 'sound/items/welderdeactivate.ogg'
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 0.75
+	light_on = FALSE
 	throw_speed = 3
 	throw_range = 5
 	w_class = WEIGHT_CLASS_SMALL
@@ -24,12 +28,12 @@
 	resistance_flags = FIRE_PROOF
 
 	materials = list(/datum/material/iron=70, /datum/material/glass=30)
-	var/welding = 0 	//Whether or not the welding tool is off(0), on(1) or currently welding(2)
+	///Whether the welding tool is on or off.
+	var/welding = FALSE
 	var/status = TRUE 		//Whether the welder is secured or unsecured (able to attach rods to it to make a flamethrower)
 	var/max_fuel = 20 	//The max amount of fuel the welder can hold
 	var/change_icons = 1
 	var/can_off_process = 0
-	var/light_intensity = 2 //how powerful the emitted light is when used.
 	var/progress_flash_divisor = 10
 	var/burned_fuel_for = 0	//when fuel was last removed
 	heat = 3800
@@ -136,7 +140,7 @@
 		var/turf/location = get_turf(user)
 		location.hotspot_expose(700, 50, 1)
 		if(get_fuel() <= 0)
-			set_light(0)
+			set_light_on(FALSE)
 
 		if(isliving(O))
 			var/mob/living/L = O
@@ -150,8 +154,6 @@
 		message_admins("[ADMIN_LOOKUPFLW(user)] activated a rigged welder at [AREACOORD(user)].")
 		explode()
 	switched_on(user)
-	if(welding)
-		set_light(light_intensity)
 
 	update_icon()
 
@@ -179,10 +181,18 @@
 	else
 		return FALSE
 
+//Toggles the welding value.
+/obj/item/weldingtool/proc/set_welding(new_value)
+	if(welding == new_value)
+		return
+	. = welding
+	welding = new_value
+	set_light_on(welding)
 
 //Turns off the welder if there is no more fuel (does this really need to be its own proc?)
 /obj/item/weldingtool/proc/check_fuel(mob/user)
 	if(get_fuel() <= 0 && welding)
+		set_light_on(FALSE)
 		switched_on(user)
 		update_icon()
 		//mob icon update
@@ -198,7 +208,7 @@
 	if(!status)
 		to_chat(user, span_warning("[src] can't be turned on while unsecured!"))
 		return
-	welding = !welding
+	set_welding(!welding)
 	if(welding)
 		if(get_fuel() >= 1)
 			to_chat(user, span_notice("You switch [src] on."))
@@ -218,8 +228,7 @@
 
 //Switches the welder off
 /obj/item/weldingtool/proc/switched_off(mob/user)
-	welding = 0
-	set_light(0)
+	set_welding(FALSE)
 
 	force = 3
 	damtype = "brute"
@@ -246,7 +255,7 @@
 			var/mob/living/carbon/human/H = user
 			if(istype(H.head,/obj/item/clothing/head/helmet/space/plasmaman))
 				return
-		user.flash_act(light_intensity)
+		user.flash_act(light_range)
 
 // Flash the user during welding progress
 /obj/item/weldingtool/tool_check_callback(mob/living/user, amount, datum/callback/extra_checks)
@@ -257,7 +266,7 @@
 				var/mob/living/carbon/human/H = user
 				if(istype(H.head,/obj/item/clothing/head/helmet/space/plasmaman))
 					return
-			user.flash_act(min(light_intensity,1))
+			user.flash_act(min(light_range,1))
 			progress_flash_divisor = initial(progress_flash_divisor)
 		else
 			progress_flash_divisor--
@@ -347,7 +356,8 @@
 	icon = 'icons/obj/abductor.dmi'
 	icon_state = "welder_alien"
 	toolspeed = 0.1
-	light_intensity = 0
+	light_system = NO_LIGHT_SUPPORT
+	light_range = 0
 	change_icons = 0
 
 /obj/item/weldingtool/abductor/process()
@@ -373,7 +383,7 @@
 	var/last_gen = 0
 	change_icons = 0
 	can_off_process = 1
-	light_intensity = 1
+	light_range = 1
 	toolspeed = 0.5
 	var/nextrefueltick = 0
 

code/game/objects/items/twohanded.dm

@@ -310,16 +310,18 @@
 	hitsound = "swing_hit"
 	armour_penetration = 35
 	var/saber_color = "green"
-	light_color = "#00ff00"//green
 	attack_verb = list("attacked", "slashed", "stabbed", "sliced", "torn", "ripped", "diced", "cut")
 	block_chance = 75
 	max_integrity = 200
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 100, ACID = 70)
 	resistance_flags = FIRE_PROOF
+	light_system = MOVABLE_LIGHT
+	light_range = 6 //TWICE AS BRIGHT AS A REGULAR ESWORD
+	light_color = "#00ff00" //green
+	light_on = FALSE
 	wound_bonus = -10
 	bare_wound_bonus = 20
 	var/hacked = FALSE
-	var/brightness_on = 6 //TWICE AS BRIGHT AS A REGULAR ESWORD
 	var/list/possible_colors = list("red", "blue", "green", "purple")
 
 /obj/item/twohanded/dualsaber/suicide_act(mob/living/carbon/user)
@@ -351,15 +353,17 @@
 	. = ..()
 	if(LAZYLEN(possible_colors))
 		saber_color = pick(possible_colors)
+		var/new_color
 		switch(saber_color)
 			if("red")
-				light_color = LIGHT_COLOR_RED
+				new_color = LIGHT_COLOR_RED
 			if("green")
-				light_color = LIGHT_COLOR_GREEN
+				new_color = LIGHT_COLOR_GREEN
 			if("blue")
-				light_color = LIGHT_COLOR_LIGHT_CYAN
+				new_color = LIGHT_COLOR_LIGHT_CYAN
 			if("purple")
-				light_color = LIGHT_COLOR_LAVENDER
+				new_color = LIGHT_COLOR_LAVENDER
+		set_light_color(new_color)
 
 /obj/item/twohanded/dualsaber/Destroy()
 	STOP_PROCESSING(SSobj, src)
@@ -420,7 +424,7 @@
 		w_class = w_class_on
 		hitsound = 'sound/weapons/blade1.ogg'
 		START_PROCESSING(SSobj, src)
-		set_light(brightness_on)
+		set_light_on(TRUE)
 
 /obj/item/twohanded/dualsaber/unwield() //Specific unwield () to switch hitsounds.
 	sharpness = initial(sharpness)
@@ -428,7 +432,7 @@
 	..()
 	hitsound = "swing_hit"
 	STOP_PROCESSING(SSobj, src)
-	set_light(0)
+	set_light_on(FALSE)
 
 /obj/item/twohanded/dualsaber/process()
 	if(wielded)
@@ -751,10 +755,10 @@
 	force = 19
 	throwforce = 24
 	force_wielded = 6
-
-/obj/item/twohanded/pitchfork/demonic/Initialize()
-	. = ..()
-	set_light(3,6,LIGHT_COLOR_RED)
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 6
+	light_color = LIGHT_COLOR_RED
 
 /obj/item/twohanded/pitchfork/demonic/greater
 	force = 24
@@ -991,6 +995,10 @@
 	w_class = WEIGHT_CLASS_HUGE
 	slot_flags = ITEM_SLOT_BACK
 	actions_types = list(/datum/action/item_action/charge_hammer)
+	light_system = MOVABLE_LIGHT
+	light_color = LIGHT_COLOR_LIGHT_CYAN
+	light_range = 2
+	light_power = 2
 	var/datum/effect_system/spark_spread/spark_system //It's a surprise tool that'll help us later
 	var/charging = FALSE
 	var/supercharged = FALSE
@@ -1042,11 +1050,11 @@
 /obj/item/twohanded/vxtvulhammer/proc/supercharge() //Proc to handle when it's charged for light + sprite + damage
 	supercharged = !supercharged
 	if(supercharged)
-		set_light(2) //Glows when charged
+		set_light_on(TRUE) //Glows when charged
 		force = initial(force) + (wielded ? force_wielded : 0) + 12 //12 additional damage for a total of 40 has to be a massively irritating check because of how force_wielded works
 		armour_penetration = 100
 	else
-		set_light(0)
+		set_light_on(TRUE)
 		force = initial(force) + (wielded ? force_wielded : 0)
 		armour_penetration = initial(armour_penetration)
 	update_icon()

code/game/objects/structures/electricchair.dm

@@ -29,9 +29,9 @@
 	var/area/A = get_area(src)
 	if(!isarea(A))
 		return
-	if(!A.powered(EQUIP))
+	if(!A.powered(AREA_USAGE_EQUIP))
 		return
-	A.use_power(EQUIP, 5000)
+	A.use_power(AREA_USAGE_EQUIP, 5000)
 
 	flick("echair_shock", src)
 	var/datum/effect_system/spark_spread/s = new /datum/effect_system/spark_spread

code/game/turfs/change_turf.dm

@@ -80,9 +80,11 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 
 	var/old_opacity = opacity
 	var/old_dynamic_lighting = dynamic_lighting
-	var/old_affecting_lights = affecting_lights
 	var/old_lighting_object = lighting_object
-	var/old_corners = corners
+	var/old_lighting_corner_NE = lighting_corner_NE
+	var/old_lighting_corner_SE = lighting_corner_SE
+	var/old_lighting_corner_SW = lighting_corner_SW
+	var/old_lighting_corner_NW = lighting_corner_NW
 
 	var/old_exl = explosion_level
 	var/old_exi = explosion_id
@@ -117,11 +119,14 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 
 	W.blueprint_data = old_bp
 
+	lighting_corner_NE = old_lighting_corner_NE
+	lighting_corner_SE = old_lighting_corner_SE
+	lighting_corner_SW = old_lighting_corner_SW
+	lighting_corner_NW = old_lighting_corner_NW
+
 	if(SSlighting.initialized)
 		recalc_atom_opacity()
 		lighting_object = old_lighting_object
-		affecting_lights = old_affecting_lights
-		corners = old_corners
 		if (old_opacity != opacity || dynamic_lighting != old_dynamic_lighting)
 			reconsider_lights()
 

code/game/turfs/space/space.dm

@@ -46,7 +46,7 @@
 	if(requires_activation)
 		SSair.add_to_active(src)
 
-	if (light_power && light_range)
+	if (light_system == STATIC_LIGHT && light_power && light_range)
 		update_light()
 
 	if (opacity)

code/game/turfs/turf.dm

@@ -71,7 +71,7 @@ GLOBAL_LIST_EMPTY(station_turfs)
 	if(color)
 		add_atom_colour(color, FIXED_COLOUR_PRIORITY)
 	
-	if (light_power && light_range)
+	if (light_system == STATIC_LIGHT && light_power && light_range)
 		update_light()
 
 	var/turf/T = SSmapping.get_turf_above(src)

code/modules/antagonists/bloodsuckers/powers/targeted/brawn.dm

@@ -213,25 +213,21 @@
 	var/mob/living/carbon/human/H = target_atom
 	H.apply_status_effect(STATUS_EFFECT_SHADOWAFFLICTED)
 	var/turf/T = get_turf(H)
-	for(var/datum/light_source/LS in T.affecting_lights)
+	for(var/datum/light_source/LS in T.get_affecting_lights())
 		var/atom/LO = LS.source_atom
 		if(isitem(LO))
 			var/obj/item/I = LO
 			if(istype(I, /obj/item/clothing/head/helmet/space/hardsuit))
 				var/obj/item/clothing/head/helmet/space/hardsuit/HA = I
-				if(HA.on)
-					HA.on = FALSE
+				HA.set_light_on(FALSE)
 			if(istype(I, /obj/item/clothing/head/helmet/space/plasmaman))
 				var/obj/item/clothing/head/helmet/space/plasmaman/PA = I
-				if(PA.on)
-					PA.on = FALSE
+				PA.set_light_on(FALSE)
 			if(istype(I, /obj/item/flashlight))
 				var/obj/item/flashlight/F = I
-				if(F.on)
-					F.on = FALSE
-					F.update_brightness()
+				F.set_light_on(FALSE)
 		if(istype(LO, /mob/living/silicon/robot))
 			var/mob/living/silicon/robot/borg = LO
 			if(!borg.lamp_cooldown)
 				borg.smash_headlamp()
-	. = ..()
+	. = ..()

code/modules/antagonists/cult/blood_magic.dm

@@ -424,12 +424,12 @@
 		user.visible_message(span_warning("[user] holds up [user.p_their()] hand, which explodes in a flash of red light!"), \
 							span_cultitalic("You attempt to stun [L] with the spell!"))
 
-		user.mob_light(_color = LIGHT_COLOR_BLOOD_MAGIC, _range = 3, _duration = 2)
+		user.mob_light(_range = 3, _color = LIGHT_COLOR_BLOOD_MAGIC, _duration = 0.2 SECONDS)
 
 		var/anti_magic_source = L.anti_magic_check()
 		if(anti_magic_source)
 
-			L.mob_light(_color = LIGHT_COLOR_HOLY_MAGIC, _range = 2, _duration = 100)
+			L.mob_light(_range = 2, _color = LIGHT_COLOR_HOLY_MAGIC, _duration = 10 SECONDS)
 			var/mutable_appearance/forbearance = mutable_appearance('icons/effects/genetics.dmi', "servitude", -MUTATIONS_LAYER)
 			L.add_overlay(forbearance)
 			addtimer(CALLBACK(L, /atom/proc/cut_overlay, forbearance), 100)

code/modules/antagonists/cult/cult_items.dm

@@ -101,6 +101,8 @@
 	throw_range = 3
 	sharpness = SHARP_EDGED
 	light_color = "#ff0000"
+	light_system = MOVABLE_LIGHT
+	light_range = 4
 	attack_verb = list("cleaved", "slashed", "torn", "hacked", "ripped", "diced", "carved")
 	icon = 'icons/obj/weapons/swords.dmi'
 	icon_state = "cultbastard"
@@ -120,7 +122,6 @@
 
 /obj/item/twohanded/required/cult_bastard/Initialize()
 	. = ..()
-	set_light(4)
 	jaunt = new(src)
 	linked_action = new(src)
 	AddComponent(/datum/component/butchering, 50, 80)
@@ -361,7 +362,7 @@
 	icon_state = "cult_helmet"
 	item_state = "cult_helmet"
 	armor = list(MELEE = 60, BULLET = 50, LASER = 30,ENERGY = 15, BOMB = 30, BIO = 30, RAD = 30, FIRE = 40, ACID = 75)
-	brightness_on = 0
+	light_system = NO_LIGHT_SUPPORT
 	actions_types = list()
 
 /obj/item/clothing/suit/space/hardsuit/cult
@@ -608,7 +609,7 @@ GLOBAL_VAR_INIT(curselimit, 0)
 	name = "void torch"
 	desc = "Used by veteran cultists to instantly transport items to their needful brethren."
 	w_class = WEIGHT_CLASS_SMALL
-	brightness_on = 1
+	light_range = 1
 	icon_state = "torch"
 	item_state = "torch"
 	color = "#ff0000"

code/modules/assembly/flash.dm

@@ -10,7 +10,10 @@
 	w_class = WEIGHT_CLASS_TINY
 	materials = list(/datum/material/iron = 300, /datum/material/glass = 300)
 	light_color = LIGHT_COLOR_WHITE
+	light_system = MOVABLE_LIGHT //Used as a flash here.
+	light_range = FLASH_LIGHT_RANGE
 	light_power = FLASH_LIGHT_POWER
+	light_on = FALSE
 	///flicked when we flash
 	var/flashing_overlay = "flash-f"
 	///Number of times the flash has been used.
@@ -109,7 +112,8 @@
 		return FALSE
 	last_trigger = world.time
 	playsound(src, 'sound/weapons/flash.ogg', 100, TRUE)
-	flash_lighting_fx(FLASH_LIGHT_RANGE, light_power, light_color)
+	set_light_on(TRUE)
+	addtimer(CALLBACK(src, .proc/flash_end), FLASH_LIGHT_DURATION, TIMER_OVERRIDE|TIMER_UNIQUE)
 	times_used++
 	flash_recharge()
 	update_icon(TRUE)
@@ -117,6 +121,9 @@
 		return FALSE
 	return TRUE
 
+/obj/item/assembly/flash/proc/flash_end()
+	set_light_on(FALSE)
+
 /obj/item/assembly/flash/proc/flash_carbon(mob/living/carbon/M, mob/user, power = 15, targeted = TRUE, generic_message = FALSE)
 	if(!istype(M))
 		return

code/modules/atmospherics/environmental/LINDA_fire.dm

@@ -47,9 +47,11 @@
 	icon = 'icons/effects/fire.dmi'
 	icon_state = "1"
 	layer = GASFIRE_LAYER
-	light_range = LIGHT_RANGE_FIRE
-	light_color = LIGHT_COLOR_FIRE
 	blend_mode = BLEND_ADD
+	light_system = MOVABLE_LIGHT
+	light_range = LIGHT_RANGE_FIRE
+	light_power = 1
+	light_color = LIGHT_COLOR_FIRE
 
 	var/volume = 125
 	var/temperature = FIRE_MINIMUM_TEMPERATURE_TO_EXIST
@@ -144,7 +146,7 @@
 		add_overlay(fusion_overlay)
 		add_overlay(rainbow_overlay)
 
-	set_light(l_color = rgb(LERP(250,heat_r,greyscale_fire),LERP(160,heat_g,greyscale_fire),LERP(25,heat_b,greyscale_fire)))
+	set_light_color(rgb(LERP(250, heat_r, greyscale_fire), LERP(160, heat_g, greyscale_fire), LERP(25, heat_b, greyscale_fire)))
 
 	heat_r /= 255
 	heat_g /= 255
@@ -206,7 +208,6 @@
 	return TRUE
 
 /obj/effect/hotspot/Destroy()
-	set_light(0)
 	SSair.hotspots -= src
 	var/turf/open/T = loc
 	if(istype(T) && T.active_hotspot == src)

code/modules/atmospherics/machinery/airalarm.dm

@@ -64,7 +64,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 4
 	active_power_usage = 8
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	req_access = list(ACCESS_ATMOSPHERICS)
 	max_integrity = 250
 	integrity_failure = 80

code/modules/atmospherics/machinery/atmosmachinery.dm

@@ -18,7 +18,7 @@ GLOBAL_LIST_EMPTY(pipeimages)
 	move_resist = INFINITY				//Moving a connected machine without actually doing the normal (dis)connection things will probably cause a LOT of issues.
 	idle_power_usage = 0
 	active_power_usage = 0
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	layer = GAS_PIPE_HIDDEN_LAYER //under wires
 	resistance_flags = FIRE_PROOF
 	max_integrity = 200

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

@@ -352,7 +352,7 @@
 
 /obj/machinery/atmospherics/components/unary/vent_pump/high_volume
 	name = "large air vent"
-	power_channel = EQUIP
+	power_channel = AREA_USAGE_EQUIP
 
 /obj/machinery/atmospherics/components/unary/vent_pump/high_volume/New()
 	..()

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

@@ -4,7 +4,7 @@
 	icon = 'icons/obj/atmospherics/pipes/meter.dmi'
 	icon_state = "meterX"
 	layer = GAS_METER_LAYER
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 2
 	active_power_usage = 4

code/modules/clothing/head/hardhat.dm

@@ -4,19 +4,24 @@
 	icon_state = "hardhat0_yellow"
 	item_state = "hardhat0_yellow"
 	mob_overlay_icon = 'icons/mob/clothing/head/head.dmi'
-	var/brightness_on = 4 //luminosity when on
-	var/on = FALSE
-	//Determines used sprites: hardhat[on]_[hat_type]
-	var/hat_type = "yellow"
 	armor = list(MELEE = 15, BULLET = 5, LASER = 20, ENERGY = 10, BOMB = 20, BIO = 10, RAD = 20, FIRE = 100, ACID = 50, WOUND = 10)
 	flags_inv = 0
 	actions_types = list(/datum/action/item_action/toggle_helmet_light)
 	resistance_flags = FIRE_PROOF
 	dynamic_hair_suffix = "+generic"
 	hattable = FALSE
+	light_system = MOVABLE_LIGHT
+	light_range = 4
+	light_power = 0.8
+	light_on = FALSE
 
 	dog_fashion = /datum/dog_fashion/head
 
+	//Determines used sprites: hardhat[on]_[hat_type]
+	var/hat_type = "yellow"
+	///Whether the headlamp is on or off.
+	var/on = FALSE
+
 /obj/item/clothing/head/hardhat/attack_self(mob/living/user)
 	toggle_helmet_light(user)
 
@@ -40,10 +45,10 @@
 	..()
 
 /obj/item/clothing/head/hardhat/proc/turn_on(mob/user)
-	set_light(brightness_on)
+	set_light_on(TRUE)
 
 /obj/item/clothing/head/hardhat/proc/turn_off(mob/user)
-	set_light(0)
+	set_light_on(FALSE)
 
 /obj/item/clothing/head/hardhat/orange
 	icon_state = "hardhat0_orange"
@@ -68,7 +73,7 @@
 	desc = "By applying state of the art lighting technology to a fire helmet, and using photo-chemical hardening methods, this hardhat will protect you from robust workplace hazards."
 	icon_state = "hardhat0_purple"
 	item_state = "hardhat0_purple"
-	brightness_on = 5
+	light_range = 5
 	heat_protection = HEAD
 	max_heat_protection_temperature = FIRE_HELM_MAX_TEMP_PROTECT
 	cold_protection = HEAD
@@ -110,7 +115,7 @@
 /obj/item/clothing/head/hardhat/weldhat
 	name = "welding hard hat"
 	desc = "A piece of headgear used in dangerous working conditions to protect the head. Comes with a built-in flashlight AND welding shield! The bulb seems a little smaller though."
-	brightness_on = 3 //Needs a little bit of tradeoff
+	light_range = 3 //Needs a little bit of tradeoff
 	dog_fashion = null
 	actions_types = list(/datum/action/item_action/toggle_helmet_light, /datum/action/item_action/toggle_welding_screen)
 	flash_protect = 2
@@ -159,7 +164,7 @@
 	desc = "A piece of headgear used in dangerous working conditions to protect the head. Comes with a built-in flashlight AND welding shield!" //This bulb is not smaller
 	icon_state = "hardhat0_white"
 	item_state = "hardhat0_white"
-	brightness_on = 4 //Boss always takes the best stuff
+	light_range = 4 //Boss always takes the best stuff
 	hat_type = "white"
 	clothing_flags = STOPSPRESSUREDAMAGE
 	heat_protection = HEAD

code/modules/clothing/head/helmet.dm

@@ -30,6 +30,12 @@
 	. = ..()
 	AddComponent(/datum/component/wearertargeting/earprotection, list(SLOT_HEAD))
 
+/obj/item/clothing/head/helmet/Destroy()
+	var/obj/item/flashlight/seclite/old_light = set_attached_light(null)
+	if(old_light)
+		qdel(old_light)
+	return ..()
+
 /obj/item/clothing/head/helmet/examine(mob/user)
 	.=..()
 	if(attached_light)
@@ -39,18 +45,31 @@
 	else if(can_flashlight)
 		. += "It has a mounting point for a <b>seclite</b>."
 
-/obj/item/clothing/head/helmet/Destroy()
-	QDEL_NULL(attached_light)
-	return ..()
-
 /obj/item/clothing/head/helmet/handle_atom_del(atom/A)
 	if(A == attached_light)
-		attached_light = null
+		set_attached_light(null)
 		update_helmlight()
 		update_icon()
 		QDEL_NULL(alight)
+		qdel(A)
 	return ..()
 
+///Called when attached_light value changes.
+/obj/item/clothing/head/helmet/proc/set_attached_light(obj/item/flashlight/seclite/new_attached_light)
+	if(attached_light == new_attached_light)
+		return
+	. = attached_light
+	attached_light = new_attached_light
+	if(attached_light)
+		attached_light.set_light_flags(attached_light.light_flags | LIGHT_ATTACHED)
+		if(attached_light.loc != src)
+			attached_light.forceMove(src)
+	else if(.)
+		var/obj/item/flashlight/seclite/old_attached_light = .
+		old_attached_light.set_light_flags(old_attached_light.light_flags & ~LIGHT_ATTACHED)
+		if(old_attached_light.loc == src)
+			old_attached_light.forceMove(get_turf(src))
+
 /obj/item/clothing/head/helmet/sec
 	can_flashlight = TRUE
 
@@ -377,9 +396,7 @@
 			if(!user.transferItemToLoc(S, src))
 				return
 			to_chat(user, span_notice("You click [S] into place on [src]."))
-			if(S.on)
-				set_light(0)
-			attached_light = S
+			set_attached_light(S)
 			update_icon()
 			update_helmlight()
 			alight = new(src)
@@ -397,8 +414,7 @@
 		if(Adjacent(user) && !issilicon(user))
 			user.put_in_hands(attached_light)
 
-		var/obj/item/flashlight/removed_light = attached_light
-		attached_light = null
+		var/obj/item/flashlight/removed_light = set_attached_light(null)
 		update_helmlight()
 		removed_light.update_brightness(user)
 		update_icon()
@@ -418,6 +434,7 @@
 	if(user.incapacitated())
 		return
 	attached_light.on = !attached_light.on
+	attached_light.update_brightness()
 	to_chat(user, span_notice("You toggle the helmet-light [attached_light.on ? "on":"off"]."))
 
 	playsound(user, 'sound/weapons/empty.ogg', 100, TRUE)
@@ -425,14 +442,7 @@
 
 /obj/item/clothing/head/helmet/proc/update_helmlight()
 	if(attached_light)
-		if(attached_light.on)
-			set_light(attached_light.brightness_on)
-		else
-			set_light(0)
 		update_icon()
-
-	else
-		set_light(0)
 	for(var/X in actions)
 		var/datum/action/A = X
 		A.UpdateButtonIcon()

code/modules/clothing/head/misc_special.dm

@@ -46,7 +46,7 @@
 	hitsound = 'sound/weapons/tap.ogg'
 	flags_inv = HIDEEARS|HIDEHAIR
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0,ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 0, ACID = 0)
-	brightness_on = 2 //luminosity when on
+	light_range = 2 //luminosity when on
 	flags_cover = HEADCOVERSEYES
 	heat = 999
 
@@ -116,7 +116,7 @@
 	hat_type = "pumpkin"
 	flags_inv = HIDEMASK|HIDEEARS|HIDEEYES|HIDEFACE|HIDEHAIR|HIDEFACIALHAIR
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0,ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 0, ACID = 0)
-	brightness_on = 2 //luminosity when on
+	light_range = 2 //luminosity when on
 	flags_cover = HEADCOVERSEYES
 	hattable = FALSE
 
@@ -166,7 +166,7 @@
 	hat_type = "reindeer"
 	flags_inv = 0
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0,ENERGY = 0, BOMB = 0, BIO = 0, RAD = 0, FIRE = 0, ACID = 0)
-	brightness_on = 1 //luminosity when on
+	light_range = 1 //luminosity when on
 	dynamic_hair_suffix = ""
 
 	dog_fashion = /datum/dog_fashion/head/reindeer

code/modules/clothing/shoes/miscellaneous.dm

@@ -336,6 +336,10 @@
 	icon_state = "kindleKicks"
 	item_state = "kindleKicks"
 	actions_types = list(/datum/action/item_action/kindleKicks)
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 3
+	light_on = FALSE
 	var/lightCycle = 0
 	var/active = FALSE
 
@@ -343,18 +347,19 @@
 	if(active)
 		return
 	active = TRUE
-	set_light(2, 3, rgb(rand(0,255),rand(0,255),rand(0,255)))
-	addtimer(CALLBACK(src, .proc/lightUp), 5)
+	set_light_color(rgb(rand(0, 255), rand(0, 255), rand(0, 255)))
+	set_light_on(active)
+	addtimer(CALLBACK(src, .proc/lightUp), 0.5 SECONDS)
 
 /obj/item/clothing/shoes/kindleKicks/proc/lightUp(mob/user)
 	if(lightCycle < 15)
-		set_light(2, 3, rgb(rand(0,255),rand(0,255),rand(0,255)))
-		lightCycle += 1
-		addtimer(CALLBACK(src, .proc/lightUp), 5)
+		set_light_color(rgb(rand(0, 255), rand(0, 255), rand(0, 255)))
+		lightCycle++
+		addtimer(CALLBACK(src, .proc/lightUp), 0.5 SECONDS)
 	else
-		set_light(0)
 		lightCycle = 0
 		active = FALSE
+		set_light_on(active)
 
 /obj/item/clothing/shoes/russian
 	name = "russian boots"

code/modules/clothing/spacesuits/hardsuit.dm

@@ -6,8 +6,11 @@
 	item_state = "eng_helm"
 	max_integrity = 300
 	armor = list(MELEE = 10, BULLET = 5, LASER = 10, ENERGY = 5, BOMB = 10, BIO = 100, RAD = 75, FIRE = 50, ACID = 75)
+	light_system = MOVABLE_LIGHT
+	light_range = 4
+	light_power = 1
+	light_on = FALSE
 	var/basestate = "hardsuit"
-	var/brightness_on = 4 //luminosity when on
 	var/on = FALSE
 	var/obj/item/clothing/suit/space/hardsuit/suit
 	//Determines used sprites: hardsuit[on]-[hardsuit_type]
@@ -33,10 +36,8 @@
 	icon_state = "[basestate][on]-[hardsuit_type]"
 	user.update_inv_head()	//so our mob-overlays update
 
-	if(on)
-		set_light(brightness_on)
-	else
-		set_light(0)
+	set_light_on(on)
+
 	for(var/X in actions)
 		var/datum/action/A = X
 		A.UpdateButtonIcon()
@@ -264,7 +265,7 @@
 	resistance_flags = FIRE_PROOF
 	heat_protection = HEAD
 	armor = list(MELEE = 30, BULLET = 5, LASER = 10, ENERGY = 5, BOMB = 50, BIO = 100, RAD = 50, FIRE = 50, ACID = 75, WOUND = 15)
-	brightness_on = 7
+	light_range = 7
 	allowed = list(/obj/item/flashlight, /obj/item/tank/internals, /obj/item/resonator, /obj/item/mining_scanner, /obj/item/t_scanner/adv_mining_scanner, /obj/item/gun/energy/kinetic_accelerator)
 
 /obj/item/clothing/head/helmet/space/hardsuit/mining/Initialize()
@@ -319,7 +320,7 @@
 		to_chat(user, span_notice("You switch your hardsuit to EVA mode, sacrificing speed for space protection."))
 		name = initial(name)
 		desc = initial(desc)
-		set_light(brightness_on)
+		set_light_on(TRUE)
 		clothing_flags |= visor_flags
 		flags_cover |= HEADCOVERSEYES | HEADCOVERSMOUTH
 		flags_inv |= visor_flags_inv
@@ -328,7 +329,7 @@
 		to_chat(user, span_notice("You switch your hardsuit to combat mode and can now run at full speed."))
 		name += " (combat)"
 		desc = alt_desc
-		set_light(0)
+		set_light_on(FALSE)
 		clothing_flags &= ~visor_flags
 		flags_cover &= ~(HEADCOVERSEYES | HEADCOVERSMOUTH)
 		flags_inv &= ~visor_flags_inv
@@ -430,7 +431,8 @@
 	icon_state = "carp_helm"
 	item_state = "syndicate"
 	armor = list(MELEE = -20, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 100, RAD = 75, FIRE = 60, ACID = 75)	//As whimpy as a space carp
-	brightness_on = 0 //luminosity when on
+	light_system = NO_LIGHT_SUPPORT
+	light_range = 0 //luminosity when on
 	actions_types = list()
 
 /obj/item/clothing/head/helmet/space/hardsuit/carp/Initialize()
@@ -703,7 +705,7 @@
 	hardsuit_type = "ert_commander"
 	armor = list(MELEE = 65, BULLET = 50, LASER = 50, ENERGY = 50, BOMB = 50, BIO = 100, RAD = 100, FIRE = 80, ACID = 80)
 	strip_delay = 130
-	brightness_on = 7
+	light_range = 7
 	resistance_flags = FIRE_PROOF
 	max_heat_protection_temperature = FIRE_IMMUNITY_MAX_TEMP_PROTECT
 

code/modules/clothing/spacesuits/plasmamen.dm

@@ -44,8 +44,10 @@
 	strip_delay = 80
 	armor = list(MELEE = 0, BULLET = 0, LASER = 0, ENERGY = 0, BOMB = 0, BIO = 100, RAD = 0, FIRE = 100, ACID = 75)
 	resistance_flags = FIRE_PROOF | ACID_PROOF
-	var/brightness_on = 4 //luminosity when the light is on
-	var/on = FALSE
+	light_system = MOVABLE_LIGHT
+	light_range = 4
+	light_on = FALSE
+	var/helmet_on = FALSE
 	actions_types = list(/datum/action/item_action/toggle_helmet_light)
 	flash_protect = 0
 	var/base_icon_state
@@ -59,15 +61,13 @@
 	toggle_helmet_light(user)
 
 /obj/item/clothing/head/helmet/space/plasmaman/proc/toggle_helmet_light(mob/user)
-	on = !on
-	if(on)
-		set_light(brightness_on)
-	else
-		set_light(0)
-
-	icon_state = "[base_icon_state][on ? "-light":""]"
+	helmet_on = !helmet_on
+	icon_state = "[base_icon_state][helmet_on ? "-light":""]"
 	item_state = icon_state
 	user.update_inv_head()
+	
+	set_light_on(helmet_on)
+	
 	for(var/X in actions)
 		var/datum/action/A=X
 		A.UpdateButtonIcon()

code/modules/clothing/under/miscellaneous.dm

@@ -816,7 +816,9 @@
 	item_state = "lampskirt_male"
 	body_parts_covered = CHEST|GROIN|LEGS|FEET
 	can_adjust = FALSE
-	var/brightness_on = 1 //luminosity when the light is on
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_on = FALSE
 	var/on = FALSE
 	actions_types = list(/datum/action/item_action/toggle_helmet_light)
 
@@ -827,10 +829,10 @@
 	user.update_inv_w_uniform() //So the mob overlay updates
 
 	if(on)
-		set_light(brightness_on)
+		set_light_on(TRUE)
 		user.visible_message(span_notice("[user] discreetly pulls a cord for the bulbs under [user.p_their()] skirt, turning [user.p_them()] on."))
 	else
-		set_light(0)
+		set_light_on(FALSE)
 
 	for(var/X in actions)
 		var/datum/action/A=X

code/modules/holodeck/items.dm

@@ -156,7 +156,7 @@
 	use_power = IDLE_POWER_USE
 	idle_power_usage = 2
 	active_power_usage = 6
-	power_channel = ENVIRON
+	power_channel = AREA_USAGE_ENVIRON
 
 /obj/machinery/readybutton/attack_ai(mob/user as mob)
 	to_chat(user, "The station AI is not to interact with these devices.")

code/modules/hydroponics/grown/ambrosia.dm

@@ -73,6 +73,7 @@
 	desc = "Eating this <i>makes</i> you immortal."
 	icon_state = "ambrosia_gaia"
 	filling_color = rgb(255, 175, 0)
+	light_system = MOVABLE_LIGHT
 	light_range = 3
 	seed = /obj/item/seeds/ambrosia/gaia
 	wine_power = 70

code/modules/hydroponics/plant_genes.dm

@@ -260,8 +260,9 @@
 	return max(S.potency*(rate + 0.01), 0.1)
 
 /datum/plant_gene/trait/glow/on_new(obj/item/reagent_containers/food/snacks/grown/G, newloc)
-	..()
-	G.set_light(glow_range(G.seed), glow_power(G.seed), glow_color)
+	. = ..()
+	G.light_system = MOVABLE_LIGHT
+	G.AddComponent(/datum/component/overlay_lighting, glow_range(G.seed), glow_power(G.seed), glow_color)
 
 /datum/plant_gene/trait/glow/shadow
 	//makes plant emit slightly purple shadows

code/modules/lighting/lighting_atom.dm

@@ -1,11 +1,21 @@
 
 /atom
-	var/light_power = 1 // Intensity of the light.
-	var/light_range = 0 // Range in tiles of the light.
-	var/light_color     // Hexadecimal RGB string representing the colour of the light.
-
-	var/tmp/datum/light_source/light // Our light source. Don't fuck with this directly unless you have a good reason!
-	var/tmp/list/light_sources       // Any light sources that are "inside" of us, for example, if src here was a mob that's carrying a flashlight, that flashlight's light source would be part of this list.
+	///Light systems, both shouldn't be active at the same time.
+	var/light_system = STATIC_LIGHT
+	///Range of the light in tiles. Zero means no light.
+	var/light_range = 0
+	///Intensity of the light. The stronger, the less shadows you will see on the lit area.
+	var/light_power = 1
+	///Hexadecimal RGB string representing the colour of the light. White by default.
+	var/light_color = COLOR_WHITE
+	///Boolean variable for toggleable lights. Has no effect without the proper light_system, light_range and light_power values.
+	var/light_on = TRUE
+	///Bitflags to determine lighting-related atom properties.
+	var/light_flags = NONE
+	///Our light source. Don't fuck with this directly unless you have a good reason!
+	var/tmp/datum/light_source/light
+	///Any light sources that are "inside" of us, for example, if src here was a mob that's carrying a flashlight, that flashlight's light source would be part of this list.
+	var/tmp/list/light_sources
 
 // The proc you should always use to set the light of this atom.
 // Nonesensical value for l_color default, so we can detect if it gets set to null.
@@ -35,6 +45,9 @@
 	if (QDELETED(src))
 		return
 
+	if(light_system != STATIC_LIGHT)
+		CRASH("update_light() for [src] with following light_system value: [light_system]")
+
 	if (!light_power || !light_range) // We won't emit light anyways, destroy the light source.
 		QDEL_NULL(light)
 	else
@@ -81,55 +94,97 @@
 
 /atom/movable/Moved(atom/OldLoc, Dir)
 	. = ..()
-	var/datum/light_source/L
-	var/thing
-	for (thing in light_sources) // Cycle through the light sources on this atom and tell them to update.
-		L = thing
-		L.source_atom.update_light()
+	for (var/datum/light_source/light as anything in light_sources) // Cycle through the light sources on this atom and tell them to update.
+		light.source_atom.update_light()
 
 /atom/vv_edit_var(var_name, var_value)
 	switch (var_name)
 		if ("light_range")
-			set_light(l_range=var_value)
+			if(light_system == STATIC_LIGHT)
+				set_light(l_range = var_value)
+			else
+				set_light_range(var_value)
 			datum_flags |= DF_VAR_EDITED
 			return TRUE
 
 		if ("light_power")
-			set_light(l_power=var_value)
+			if(light_system == STATIC_LIGHT)
+				set_light(l_power = var_value)
+			else
+				set_light_power(var_value)
 			datum_flags |= DF_VAR_EDITED
 			return TRUE
 
 		if ("light_color")
-			set_light(l_color=var_value)
+			if(light_system == STATIC_LIGHT)
+				set_light(l_color = var_value)
+			else
+				set_light_color(var_value)
 			datum_flags |= DF_VAR_EDITED
 			return TRUE
 
 	return ..()
 
 
-/atom/proc/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = LIGHT_COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
+/atom/proc/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = COLOR_WHITE, _duration = FLASH_LIGHT_DURATION)
 	return
 
-/turf/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = LIGHT_COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
+/turf/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = COLOR_WHITE, _duration = FLASH_LIGHT_DURATION)
 	if(!_duration)
 		stack_trace("Lighting FX obj created on a turf without a duration")
-	new /obj/effect/dummy/lighting_obj (src, _color, _range, _power, _duration)
+	new /obj/effect/dummy/lighting_obj (src, _range, _power, _color, _duration)
 
-/obj/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = LIGHT_COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
-	var/temp_color
-	var/temp_power
-	var/temp_range
-	if(!_reset_lighting) //incase the obj already has a lighting color that you don't want cleared out after, ie computer monitors.
-		temp_color = light_color
-		temp_power = light_power
-		temp_range = light_range
-	set_light(_range, _power, _color)
-	addtimer(CALLBACK(src, /atom/proc/set_light, _reset_lighting ? initial(light_range) : temp_range, _reset_lighting ? initial(light_power) : temp_power, _reset_lighting ? initial(light_color) : temp_color), _duration, TIMER_OVERRIDE|TIMER_UNIQUE)
+/obj/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = COLOR_WHITE, _duration = FLASH_LIGHT_DURATION)
+	if(!_duration)
+		stack_trace("Lighting FX obj created on a obj without a duration")
+	new /obj/effect/dummy/lighting_obj (get_turf(src), _range, _power, _color, _duration)
 
-/mob/living/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = LIGHT_COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
-	mob_light(_color, _range, _power, _duration)
 
-/mob/living/proc/mob_light(_color, _range, _power, _duration)
-	var/obj/effect/dummy/lighting_obj/moblight/mob_light_obj = new (src, _color, _range, _power, _duration)
+/mob/living/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = COLOR_WHITE, _duration = FLASH_LIGHT_DURATION)
+	mob_light(_range, _power, _color, _duration)
+
+
+/mob/living/proc/mob_light(_range, _power, _color, _duration)
+	var/obj/effect/dummy/lighting_obj/moblight/mob_light_obj = new (src, _range, _power, _color, _duration)
 	return mob_light_obj
 
+
+/atom/proc/set_light_range(new_range)
+	if(new_range == light_range)
+		return
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_LIGHT_RANGE, new_range)
+	. = light_range
+	light_range = new_range
+
+
+/atom/proc/set_light_power(new_power)
+	if(new_power == light_power)
+		return
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_LIGHT_POWER, new_power)
+	. = light_power
+	light_power = new_power
+
+
+/atom/proc/set_light_color(new_color)
+	if(new_color == light_color)
+		return
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_LIGHT_COLOR, new_color)
+	. = light_color
+	light_color = new_color
+
+
+/atom/proc/set_light_on(new_value)
+	if(new_value == light_on)
+		return
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_LIGHT_ON, new_value)
+	. = light_on
+	light_on = new_value
+
+
+/atom/proc/set_light_flags(new_value)
+	if(new_value == light_flags)
+		return
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_LIGHT_FLAGS, new_value)
+	. = light_flags
+	light_flags = new_value
+

code/modules/lighting/lighting_corner.dm

@@ -2,32 +2,35 @@
 // And corners get shared between multiple turfs (unless you're on the corners of the map, then 1 corner doesn't).
 // For the record: these should never ever ever be deleted, even if the turf doesn't have dynamic lighting.
 
-// This list is what the code that assigns corners listens to, the order in this list is the order in which corners are added to the /turf/corners list.
-GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST, NORTHWEST))
-
 /datum/lighting_corner
-	var/list/turf/masters
 	var/list/datum/light_source/affecting // Light sources affecting us.
-	var/active                            = FALSE  // TRUE if one of our masters has dynamic lighting.
 
-	var/x     = 0
-	var/y     = 0
+	var/x = 0
+	var/y = 0
+
+	var/turf/master_NE
+	var/turf/master_SE
+	var/turf/master_SW
+	var/turf/master_NW
 
 	var/lum_r = 0
 	var/lum_g = 0
 	var/lum_b = 0
 
-	var/needs_update = FALSE
+	//true color values, guaranteed to be between 0 and 1
+	var/cache_r = LIGHTING_SOFT_THRESHOLD
+	var/cache_g = LIGHTING_SOFT_THRESHOLD
+	var/cache_b = LIGHTING_SOFT_THRESHOLD
 
-	var/cache_r  = LIGHTING_SOFT_THRESHOLD
-	var/cache_g  = LIGHTING_SOFT_THRESHOLD
-	var/cache_b  = LIGHTING_SOFT_THRESHOLD
-	var/cache_mx = 0
+	///the maximum of lum_r, lum_g, and lum_b. if this is > 1 then the three cached color values are divided by this
+	var/largest_color_luminosity = 0
+
+	///whether we are to be added to SSlighting's corners_queue list for an update
+	var/needs_update = FALSE
 
 /datum/lighting_corner/New(var/turf/new_turf, var/diagonal)
 	. = ..()
-	masters = list()
-	masters[new_turf] = turn(diagonal, 180)
+	save_master(new_turf, turn(diagonal, 180))
 
 	var/vertical   = diagonal & ~(diagonal - 1) // The horizontal directions (4 and 8) are bigger than the vertical ones (1 and 2), so we can reliably say the lsb is the horizontal direction.
 	var/horizontal = diagonal & ~vertical       // Now that we know the horizontal one we can get the vertical one.
@@ -38,50 +41,49 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	// My initial plan was to make this loop through a list of all the dirs (horizontal, vertical, diagonal).
 	// Issue being that the only way I could think of doing it was very messy, slow and honestly overengineered.
 	// So we'll have this hardcode instead.
-	var/turf/T
-	var/i
+	var/turf/new_master_turf
 
 	// Diagonal one is easy.
-	T = get_step(new_turf, diagonal)
-	if (T) // In case we're on the map's border.
-		if (!T.corners)
-			T.corners = list(null, null, null, null)
-
-		masters[T]   = diagonal
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(diagonal, 180))
-		T.corners[i] = src
+	new_master_turf = get_step(new_turf, diagonal)
+	if (new_master_turf) // In case we're on the map's border.
+		save_master(new_master_turf, diagonal)
 
 	// Now the horizontal one.
-	T = get_step(new_turf, horizontal)
-	if (T) // Ditto.
-		if (!T.corners)
-			T.corners = list(null, null, null, null)
-
-		masters[T]   = ((T.x > x) ? EAST : WEST) | ((T.y > y) ? NORTH : SOUTH) // Get the dir based on coordinates.
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(masters[T], 180))
-		T.corners[i] = src
+	new_master_turf = get_step(new_turf, horizontal)
+	if (new_master_turf) // Ditto.
+		save_master(new_master_turf, ((new_master_turf.x > x) ? EAST : WEST) | ((new_master_turf.y > y) ? NORTH : SOUTH)) // Get the dir based on coordinates.
 
 	// And finally the vertical one.
-	T = get_step(new_turf, vertical)
-	if (T)
-		if (!T.corners)
-			T.corners = list(null, null, null, null)
+	new_master_turf = get_step(new_turf, vertical)
+	if (new_master_turf)
+		save_master(new_master_turf, ((new_master_turf.x > x) ? EAST : WEST) | ((new_master_turf.y > y) ? NORTH : SOUTH)) // Get the dir based on coordinates.
 
-		masters[T]   = ((T.x > x) ? EAST : WEST) | ((T.y > y) ? NORTH : SOUTH) // Get the dir based on coordinates.
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(masters[T], 180))
-		T.corners[i] = src
+/datum/lighting_corner/proc/save_master(turf/master, dir)
+	switch (dir)
+		if (NORTHEAST)
+			master_NE = master
+			master.lighting_corner_SW = src
+		if (SOUTHEAST)
+			master_SE = master
+			master.lighting_corner_NW = src
+		if (SOUTHWEST)
+			master_SW = master
+			master.lighting_corner_NE = src
+		if (NORTHWEST)
+			master_NW = master
+			master.lighting_corner_SE = src
 
-	update_active()
+/datum/lighting_corner/proc/self_destruct_if_idle()
+	if (!LAZYLEN(affecting))
+		qdel(src, force = TRUE)
 
-/datum/lighting_corner/proc/update_active()
-	active = FALSE
-	var/turf/T
-	var/thing
-	for (thing in masters)
-		T = thing
-		if (T.lighting_object)
-			active = TRUE
-			return
+/datum/lighting_corner/proc/vis_update()
+	for (var/datum/light_source/light_source as anything in affecting)
+		light_source.vis_update()
+
+/datum/lighting_corner/proc/full_update()
+	for (var/datum/light_source/light_source as anything in affecting)
+		light_source.recalc_corner(src)
 
 // God that was a mess, now to do the rest of the corner code! Hooray!
 /datum/lighting_corner/proc/update_lumcount(delta_r, delta_g, delta_b)
@@ -94,20 +96,20 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 
 	if (!needs_update)
 		needs_update = TRUE
-		GLOB.lighting_update_corners += src
+		SSlighting.corners_queue += src
 
 /datum/lighting_corner/proc/update_objects()
 	// Cache these values ahead of time so 4 individual lighting objects don't all calculate them individually.
 	var/lum_r = src.lum_r
 	var/lum_g = src.lum_g
 	var/lum_b = src.lum_b
-	var/mx = max(lum_r, lum_g, lum_b) // Scale it so one of them is the strongest lum, if it is above 1.
+	var/largest_color_luminosity = max(lum_r, lum_g, lum_b) // Scale it so one of them is the strongest lum, if it is above 1.
 	. = 1 // factor
-	if (mx > 1)
-		. = 1 / mx
+	if (largest_color_luminosity > 1)
+		. = 1 / largest_color_luminosity
 
 	#if LIGHTING_SOFT_THRESHOLD != 0
-	else if (mx < LIGHTING_SOFT_THRESHOLD)
+	else if (largest_color_luminosity < LIGHTING_SOFT_THRESHOLD)
 		. = 0 // 0 means soft lighting.
 
 	cache_r  = round(lum_r * ., LIGHTING_ROUND_VALUE) || LIGHTING_SOFT_THRESHOLD
@@ -118,13 +120,29 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	cache_g  = round(lum_g * ., LIGHTING_ROUND_VALUE)
 	cache_b  = round(lum_b * ., LIGHTING_ROUND_VALUE)
 	#endif
-	cache_mx = round(mx, LIGHTING_ROUND_VALUE)
+	src.largest_color_luminosity = round(largest_color_luminosity, LIGHTING_ROUND_VALUE)
 
-	for (var/TT in masters)
-		var/turf/T = TT
-		if (T.lighting_object && !T.lighting_object.needs_update)
-			T.lighting_object.needs_update = TRUE
-			GLOB.lighting_update_objects += T.lighting_object
+	var/datum/lighting_object/lighting_object = master_NE?.lighting_object
+	if (lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_SE?.lighting_object
+	if (lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_SW?.lighting_object
+	if (lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_NW?.lighting_object
+	if (lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	self_destruct_if_idle()
 
 
 /datum/lighting_corner/dummy/New()
@@ -134,6 +152,23 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	if (!force)
 		return QDEL_HINT_LETMELIVE
 
-	stack_trace("Ok, Look, /tg/, I need you to find whatever fucker decided to call qdel on a fucking lighting corner, then tell him very nicely and politely that he is 100% retarded and needs his head checked. Thanks. Send them my regards by the way.")
+	for (var/datum/light_source/light_source as anything in affecting)
+		LAZYREMOVE(light_source.effect_str, src)
+	affecting = null
+
+	if (master_NE)
+		master_NE.lighting_corner_SW = null
+		master_NE.lighting_corners_initialised = FALSE
+	if (master_SE)
+		master_SE.lighting_corner_NW = null
+		master_SE.lighting_corners_initialised = FALSE
+	if (master_SW)
+		master_SW.lighting_corner_NE = null
+		master_SW.lighting_corners_initialised = FALSE
+	if (master_NW)
+		master_NW.lighting_corner_SE = null
+		master_NW.lighting_corners_initialised = FALSE
+	if (needs_update)
+		SSlighting.corners_queue -= src
 
 	return ..()

code/modules/lighting/lighting_object.dm

@@ -29,12 +29,12 @@
 		space_tile.update_starlight()
 
 	needs_update = TRUE
-	GLOB.lighting_update_objects += src
+	SSlighting.objects_queue += src
 
 /datum/lighting_object/Destroy(force)
 	if (!force)
 		return QDEL_HINT_LETMELIVE
-	GLOB.lighting_update_objects -= src
+	SSlighting.objects_queue -= src
 	if (isturf(affected_turf))
 		affected_turf.lighting_object = null
 		affected_turf.luminosity = 1
@@ -54,34 +54,28 @@
 
 	var/static/datum/lighting_corner/dummy/dummy_lighting_corner = new
 
-	var/list/corners = affected_turf.corners
-	var/datum/lighting_corner/cr = dummy_lighting_corner
-	var/datum/lighting_corner/cg = dummy_lighting_corner
-	var/datum/lighting_corner/cb = dummy_lighting_corner
-	var/datum/lighting_corner/ca = dummy_lighting_corner
-	if (corners) //done this way for speed
-		cr = corners[3] || dummy_lighting_corner
-		cg = corners[2] || dummy_lighting_corner
-		cb = corners[4] || dummy_lighting_corner
-		ca = corners[1] || dummy_lighting_corner
+	var/datum/lighting_corner/red_corner = affected_turf.lighting_corner_SW || dummy_lighting_corner
+	var/datum/lighting_corner/green_corner = affected_turf.lighting_corner_SE || dummy_lighting_corner
+	var/datum/lighting_corner/blue_corner = affected_turf.lighting_corner_NW || dummy_lighting_corner
+	var/datum/lighting_corner/alpha_corner = affected_turf.lighting_corner_NE || dummy_lighting_corner
 
-	var/max = max(cr.cache_mx, cg.cache_mx, cb.cache_mx, ca.cache_mx)
+	var/max = max(red_corner.largest_color_luminosity, green_corner.largest_color_luminosity, blue_corner.largest_color_luminosity, alpha_corner.largest_color_luminosity)
 
-	var/rr = cr.cache_r
-	var/rg = cr.cache_g
-	var/rb = cr.cache_b
+	var/rr = red_corner.cache_r
+	var/rg = red_corner.cache_g
+	var/rb = red_corner.cache_b
 
-	var/gr = cg.cache_r
-	var/gg = cg.cache_g
-	var/gb = cg.cache_b
+	var/gr = green_corner.cache_r
+	var/gg = green_corner.cache_g
+	var/gb = green_corner.cache_b
 
-	var/br = cb.cache_r
-	var/bg = cb.cache_g
-	var/bb = cb.cache_b
+	var/br = blue_corner.cache_r
+	var/bg = blue_corner.cache_g
+	var/bb = blue_corner.cache_b
 
-	var/ar = ca.cache_r
-	var/ag = ca.cache_g
-	var/ab = ca.cache_b
+	var/ar = alpha_corner.cache_r
+	var/ag = alpha_corner.cache_g
+	var/ab = alpha_corner.cache_b
 
 	#if LIGHTING_SOFT_THRESHOLD != 0
 	var/set_luminosity = max > LIGHTING_SOFT_THRESHOLD

code/modules/lighting/lighting_source.dm

@@ -2,14 +2,21 @@
 // These are the main datums that emit light.
 
 /datum/light_source
-	var/atom/top_atom        // The atom we're emitting light from (for example a mob if we're from a flashlight that's being held).
-	var/atom/source_atom     // The atom that we belong to.
+	///The atom we're emitting light from (for example a mob if we're from a flashlight that's being held).
+	var/atom/top_atom
+	///The atom that we belong to.
+	var/atom/source_atom
 
-	var/turf/source_turf     // The turf under the above.
-	var/turf/pixel_turf      // The turf the top_atom appears to over.
-	var/light_power    // Intensity of the emitter light.
-	var/light_range      // The range of the emitted light.
-	var/light_color    // The colour of the light, string, decomposed by parse_light_color()
+	///The turf under the source atom.
+	var/turf/source_turf
+	///The turf the top_atom appears to over.
+	var/turf/pixel_turf
+	///Intensity of the emitter light.
+	var/light_power
+	/// The range of the emitted light.
+	var/light_range
+	/// The colour of the light, string, decomposed by parse_light_color()
+	var/light_color
 
 	// Variables for keeping track of the colour.
 	var/lum_r
@@ -21,12 +28,14 @@
 	var/tmp/applied_lum_g
 	var/tmp/applied_lum_b
 
-	var/list/datum/lighting_corner/effect_str     // List used to store how much we're affecting corners.
-	var/list/turf/affecting_turfs
+	/// List used to store how much we're affecting corners.
+	var/list/datum/lighting_corner/effect_str
 
-	var/applied = FALSE // Whether we have applied our light yet or not.
+	/// Whether we have applied our light yet or not.
+	var/applied = FALSE
 
-	var/needs_update = LIGHTING_NO_UPDATE    // Whether we are queued for an update.
+	/// whether we are to be added to SSlighting's sources_queue list for an update
+	var/needs_update = LIGHTING_NO_UPDATE
 
 
 /datum/light_source/New(var/atom/owner, var/atom/top)
@@ -56,7 +65,7 @@
 		LAZYREMOVE(top_atom.light_sources, src)
 
 	if (needs_update)
-		GLOB.lighting_update_lights -= src
+		SSlighting.sources_queue -= src
 
 	. = ..()
 
@@ -65,7 +74,7 @@
 // Actually that'd be great if you could!
 #define EFFECT_UPDATE(level)                \
 	if (needs_update == LIGHTING_NO_UPDATE) \
-		GLOB.lighting_update_lights += src; \
+		SSlighting.sources_queue += src;    \
 	if (needs_update < level)               \
 		needs_update            = level;    \
 
@@ -99,56 +108,43 @@
 // The braces and semicolons are there to be able to do this on a single line.
 #define LUM_FALLOFF(C, T) (1 - CLAMP01(sqrt((C.x - T.x) ** 2 + (C.y - T.y) ** 2 + LIGHTING_HEIGHT) / max(1, light_range)))
 
-#define APPLY_CORNER(C)                      \
-	. = LUM_FALLOFF(C, pixel_turf);          \
-	. *= light_power;                        \
-	var/OLD = effect_str[C];                 \
-	effect_str[C] = .;                       \
-                                             \
-	C.update_lumcount                        \
-	(                                        \
-		(. * lum_r) - (OLD * applied_lum_r), \
-		(. * lum_g) - (OLD * applied_lum_g), \
-		(. * lum_b) - (OLD * applied_lum_b)  \
-	);
+#define APPLY_CORNER(C)                          \
+	. = LUM_FALLOFF(C, pixel_turf);              \
+	. *= light_power;                            \
+	var/OLD = effect_str[C];                     \
+	                                             \
+	C.update_lumcount                            \
+	(                                            \
+		(. * lum_r) - (OLD * applied_lum_r),     \
+		(. * lum_g) - (OLD * applied_lum_g),     \
+		(. * lum_b) - (OLD * applied_lum_b)      \
+	);                                           \
 
-#define REMOVE_CORNER(C)                     \
-	. = -effect_str[C];                      \
-	C.update_lumcount                        \
-	(                                        \
-		. * applied_lum_r,                   \
-		. * applied_lum_g,                   \
-		. * applied_lum_b                    \
+#define REMOVE_CORNER(C)                         \
+	. = -effect_str[C];                          \
+	C.update_lumcount                            \
+	(                                            \
+		. * applied_lum_r,                       \
+		. * applied_lum_g,                       \
+		. * applied_lum_b                        \
 	);
 
 // This is the define used to calculate falloff.
 
 /datum/light_source/proc/remove_lum()
 	applied = FALSE
-	var/thing
-	for (thing in affecting_turfs)
-		var/turf/T = thing
-		LAZYREMOVE(T.affecting_lights, src)
+	for (var/datum/lighting_corner/corner as anything in effect_str)
+		REMOVE_CORNER(corner)
+		LAZYREMOVE(corner.affecting, src)
 
-	affecting_turfs = null
-
-	var/datum/lighting_corner/C
-	for (thing in effect_str)
-		C = thing
-		REMOVE_CORNER(C)
-
-		LAZYREMOVE(C.affecting, src)
-
-	effect_str = null
-
-/datum/light_source/proc/recalc_corner(var/datum/lighting_corner/C)
+/datum/light_source/proc/recalc_corner(var/datum/lighting_corner/corner)
 	LAZYINITLIST(effect_str)
-	if (effect_str[C]) // Already have one.
-		REMOVE_CORNER(C)
-		effect_str[C] = 0
+	if (effect_str[corner]) // Already have one.
+		REMOVE_CORNER(corner)
+		effect_str[corner] = 0
 
-	APPLY_CORNER(C)
-	UNSETEMPTY(effect_str)
+	APPLY_CORNER(corner)
+	effect_str[corner] = .
 
 
 /datum/light_source/proc/update_corners()
@@ -185,9 +181,9 @@
 		pixel_turf = get_turf_pixel(top_atom)
 		update = TRUE
 	else
-		var/P = get_turf_pixel(top_atom)
-		if (P != pixel_turf)
-			pixel_turf = P
+		var/pixel_loc = get_turf_pixel(top_atom)
+		if (pixel_loc != pixel_turf)
+			pixel_turf = pixel_loc
 			update = TRUE
 
 	if (!isturf(source_turf))
@@ -213,77 +209,56 @@
 		return //nothing's changed
 
 	var/list/datum/lighting_corner/corners = list()
-	var/list/turf/turfs                    = list()
-	var/thing
-	var/datum/lighting_corner/C
-	var/turf/T
+	var/list/turf/turfs = list()
 
 	if (source_turf)
 		var/oldlum = source_turf.luminosity
 		source_turf.luminosity = CEILING(light_range, 1)
-		for(T in view(CEILING(light_range, 1), source_turf))
-			if((!IS_DYNAMIC_LIGHTING(T) && !T.light_sources) || T.has_opaque_atom)
-				continue
-			if (!T.lighting_corners_initialised)
-				T.generate_missing_corners()
-			for (thing in T.corners)
-				C = thing
-				corners[C] = 0
+		for(var/turf/T in view(CEILING(light_range, 1), source_turf))
+			if(!T.has_opaque_atom)
+				if (!T.lighting_corners_initialised)
+					T.generate_missing_corners()
+				corners[T.lighting_corner_NE] = 0
+				corners[T.lighting_corner_SE] = 0
+				corners[T.lighting_corner_SW] = 0
+				corners[T.lighting_corner_NW] = 0
 			turfs += T
 		source_turf.luminosity = oldlum
 
-	LAZYINITLIST(affecting_turfs)
-	var/list/L = turfs - affecting_turfs // New turfs, add us to the affecting lights of them.
-	affecting_turfs += L
-	for (thing in L)
-		T = thing
-		LAZYADD(T.affecting_lights, src)
-
-	L = affecting_turfs - turfs // Now-gone turfs, remove us from the affecting lights.
-	affecting_turfs -= L
-	for (thing in L)
-		T = thing
-		LAZYREMOVE(T.affecting_lights, src)
-
+	var/list/datum/lighting_corner/new_corners = (corners - effect_str)
 	LAZYINITLIST(effect_str)
 	if (needs_update == LIGHTING_VIS_UPDATE)
-		for (thing in  corners - effect_str) // New corners
-			C = thing
-			LAZYADD(C.affecting, src)
-			if (!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for (var/datum/lighting_corner/corner as anything in new_corners)
+			APPLY_CORNER(corner)
+			if (. != 0)
+				LAZYADD(corner.affecting, src)
+				effect_str[corner] = .
 	else
-		L = corners - effect_str
-		for (thing in L) // New corners
-			C = thing
-			LAZYADD(C.affecting, src)
-			if (!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for (var/datum/lighting_corner/corner as anything in new_corners)
+			APPLY_CORNER(corner)
+			if (. != 0)
+				LAZYADD(corner.affecting, src)
+				effect_str[corner] = .
 
-		for (thing in corners - L) // Existing corners
-			C = thing
-			if (!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for (var/datum/lighting_corner/corner as anything in corners - new_corners) // Existing corners
+			APPLY_CORNER(corner)
+			if (. != 0)
+				effect_str[corner] = .
+			else
+				LAZYREMOVE(corner.affecting, src)
+				effect_str -= corner
 
-	L = effect_str - corners
-	for (thing in L) // Old, now gone, corners.
-		C = thing
-		REMOVE_CORNER(C)
-		LAZYREMOVE(C.affecting, src)
-	effect_str -= L
+	var/list/datum/lighting_corner/gone_corners = effect_str - corners
+	for (var/datum/lighting_corner/corner as anything in gone_corners)
+		REMOVE_CORNER(corner)
+		LAZYREMOVE(corner.affecting, src)
+	effect_str -= gone_corners
 
 	applied_lum_r = lum_r
 	applied_lum_g = lum_g
 	applied_lum_b = lum_b
 
 	UNSETEMPTY(effect_str)
-	UNSETEMPTY(affecting_turfs)
 
 #undef EFFECT_UPDATE
 #undef LUM_FALLOFF

code/modules/lighting/lighting_turf.dm

@@ -4,76 +4,68 @@
 
 	var/tmp/lighting_corners_initialised = FALSE
 
-	var/tmp/list/datum/light_source/affecting_lights       // List of light sources affecting this turf.
 	var/tmp/datum/lighting_object/lighting_object // Our lighting object.
-	var/tmp/list/datum/lighting_corner/corners
+
+	///Lighting Corner datums.
+	var/tmp/datum/lighting_corner/lighting_corner_NE
+	var/tmp/datum/lighting_corner/lighting_corner_SE
+	var/tmp/datum/lighting_corner/lighting_corner_SW
+	var/tmp/datum/lighting_corner/lighting_corner_NW
+
 	var/tmp/has_opaque_atom = FALSE // Not to be confused with opacity, this will be TRUE if there's any opaque atom on the tile.
 
+	///Lumcount added by sources other than lighting datum objects, such as the overlay lighting component.
+	var/dynamic_lumcount = 0
+
 // Causes any affecting light sources to be queued for a visibility update, for example a door got opened.
 /turf/proc/reconsider_lights()
-	var/datum/light_source/L
-	var/thing
-	for (thing in affecting_lights)
-		L = thing
-		L.vis_update()
+	lighting_corner_NE?.vis_update()
+	lighting_corner_SE?.vis_update()
+	lighting_corner_SW?.vis_update()
+	lighting_corner_NW?.vis_update()
 
 /turf/proc/lighting_clear_overlay()
 	if (lighting_object)
-		qdel(lighting_object, TRUE)
-
-	var/datum/lighting_corner/C
-	var/thing
-	for (thing in corners)
-		if(!thing)
-			continue
-		C = thing
-		C.update_active()
+		qdel(lighting_object, force=TRUE)
 
 // Builds a lighting object for us, but only if our area is dynamic.
 /turf/proc/lighting_build_overlay()
 	if (lighting_object)
-		qdel(lighting_object,force=TRUE) //Shitty fix for lighting objects persisting after death
+		qdel(lighting_object, force=TRUE) //Shitty fix for lighting objects persisting after death
 
-	var/area/A = loc
-	if (!IS_DYNAMIC_LIGHTING(A) && !light_sources)
+	var/area/our_area = loc
+	if (!IS_DYNAMIC_LIGHTING(our_area) && !light_sources)
 		return
 
-	if (!lighting_corners_initialised)
-		generate_missing_corners()
-
 	new/datum/lighting_object(src)
 
-	var/thing
-	var/datum/lighting_corner/C
-	var/datum/light_source/S
-	for (thing in corners)
-		if(!thing)
-			continue
-		C = thing
-		if (!C.active) // We would activate the corner, calculate the lighting for it.
-			for (thing in C.affecting)
-				S = thing
-				S.recalc_corner(C)
-			C.active = TRUE
-
 // Used to get a scaled lumcount.
 /turf/proc/get_lumcount(var/minlum = 0, var/maxlum = 1)
 	if (!lighting_object)
 		return 1
 
 	var/totallums = 0
-	var/thing
 	var/datum/lighting_corner/L
-	for (thing in corners)
-		if(!thing)
-			continue
-		L = thing
+	L = lighting_corner_NE
+	if (L)
 		totallums += L.lum_r + L.lum_b + L.lum_g
+	L = lighting_corner_SE
+	if (L)
+		totallums += L.lum_r + L.lum_b + L.lum_g
+	L = lighting_corner_SW
+	if (L)
+		totallums += L.lum_r + L.lum_b + L.lum_g
+	L = lighting_corner_NW
+	if (L)
+		totallums += L.lum_r + L.lum_b + L.lum_g
+
 
 	totallums /= 12 // 4 corners, each with 3 channels, get the average.
 
 	totallums = (totallums - minlum) / (maxlum - minlum)
 
+	totallums += dynamic_lumcount
+
 	return CLAMP01(totallums)
 
 // Returns a boolean whether the turf is on soft lighting.
@@ -111,14 +103,38 @@
 				lighting_clear_overlay()
 
 /turf/proc/generate_missing_corners()
-	if (!IS_DYNAMIC_LIGHTING(src) && !light_sources)
-		return
+	if (!lighting_corner_NE)
+		lighting_corner_NE = new/datum/lighting_corner(src, NORTH|EAST)
+
+	if (!lighting_corner_SE)
+		lighting_corner_SE = new/datum/lighting_corner(src, SOUTH|EAST)
+
+	if (!lighting_corner_SW)
+		lighting_corner_SW = new/datum/lighting_corner(src, SOUTH|WEST)
+
+	if (!lighting_corner_NW)
+		lighting_corner_NW = new/datum/lighting_corner(src, NORTH|WEST)
+
 	lighting_corners_initialised = TRUE
-	if (!corners)
-		corners = list(null, null, null, null)
 
-	for (var/i = 1 to 4)
-		if (corners[i]) // Already have a corner on this direction.
-			continue
+/turf/proc/get_affecting_lights()
+	var/list/affecting = list()
 
-		corners[i] = new/datum/lighting_corner(src, GLOB.LIGHTING_CORNER_DIAGONAL[i])
+	if (!lighting_object)
+		return affecting
+
+	var/datum/lighting_corner/L
+	L = lighting_corner_NE
+	if (L)
+		affecting += L.affecting
+	L = lighting_corner_SE
+	if (L)
+		affecting += L.affecting
+	L = lighting_corner_SW
+	if (L)
+		affecting += L.affecting
+	L = lighting_corner_NW
+	if (L)
+		affecting += L.affecting
+
+	return uniqueList(affecting)

code/modules/mining/lavaland/necropolis_chests.dm

@@ -340,7 +340,9 @@ GLOBAL_LIST_EMPTY(bloodmen_list)
 	desc = "Happy to light your way."
 	icon = 'icons/obj/lighting.dmi'
 	icon_state = "orb"
+	light_system = MOVABLE_LIGHT
 	light_range = 7
+	light_flags = LIGHT_ATTACHED
 	layer = ABOVE_ALL_MOB_LAYER
 	var/sight_flags = SEE_MOBS
 	var/lighting_alpha = LIGHTING_PLANE_ALPHA_MOSTLY_VISIBLE

code/modules/mining/minebot.dm

@@ -37,8 +37,10 @@
 	healable = 0
 	loot = list(/obj/effect/decal/cleanable/robot_debris)
 	del_on_death = TRUE
+	light_system = MOVABLE_LIGHT
+	light_range = 6
+	light_on = FALSE
 	var/mode = MINEDRONE_COLLECT
-	var/light_on = 0
 	var/obj/item/gun/energy/kinetic_accelerator/minebot/stored_gun
 
 /mob/living/simple_animal/hostile/mining_drone/Initialize()
@@ -234,11 +236,7 @@
 /datum/action/innate/minedrone/toggle_light/Activate()
 	var/mob/living/simple_animal/hostile/mining_drone/user = owner
 
-	if(user.light_on)
-		user.set_light(0)
-	else
-		user.set_light(6)
-	user.light_on = !user.light_on
+	user.set_light_on(!user.light_on)
 	to_chat(user, span_notice("You toggle your light [user.light_on ? "on" : "off"]."))
 
 /datum/action/innate/minedrone/toggle_mode

code/modules/mob/dead/observer/observer.dm

@@ -17,6 +17,10 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 	invisibility = INVISIBILITY_OBSERVER
 	hud_type = /datum/hud/ghost
 	movement_type = GROUND | FLYING
+	light_system = MOVABLE_LIGHT
+	light_range = 1
+	light_power = 2
+	light_on = FALSE
 	var/can_reenter_corpse
 	var/bootime = 0
 	var/started_as_observer //This variable is set to 1 when you enter the game as an observer.
@@ -926,10 +930,7 @@ This is the proc mobs get to turn into a ghost. Forked from ghostize due to comp
 
 /mob/dead/observer/proc/set_invisibility(value)
 	invisibility = value
-	if(!value)
-		set_light(1, 2)
-	else
-		set_light(0, 0)
+	set_light_on(!value ? TRUE : FALSE)
 
 // Ghosts have no momentum, being massless ectoplasm
 /mob/dead/observer/Process_Spacemove(movement_dir)

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

@@ -47,20 +47,32 @@
 
 	smells_like = "crackling sweetness"
 
+	var/obj/effect/dummy/lighting_obj/ethereal_light
+
+
+/datum/species/ethereal/Destroy(force)
+	if(ethereal_light)
+		QDEL_NULL(ethereal_light)
+	return ..()
+
 
 /datum/species/ethereal/on_species_gain(mob/living/carbon/C, datum/species/old_species, pref_load)
-	.=..()
-	if(ishuman(C))
-		var/mob/living/carbon/human/H = C
-		default_color = "#" + H.dna.features["ethcolor"]
-		r1 = GETREDPART(default_color)
-		g1 = GETGREENPART(default_color)
-		b1 = GETBLUEPART(default_color)
-		spec_updatehealth(H)
+	. = ..()
+	if(!ishuman(C))
+		return
+	var/mob/living/carbon/human/ethereal = C
+	default_color = "#[ethereal.dna.features["ethcolor"]]"
+	r1 = GETREDPART(default_color)
+	g1 = GETGREENPART(default_color)
+	b1 = GETBLUEPART(default_color)
+	//RegisterSignal(ethereal, COMSIG_ATOM_EMAG_ACT, .proc/on_emag_act)
+	//RegisterSignal(ethereal, COMSIG_ATOM_EMP_ACT, .proc/on_emp_act)
+	ethereal_light = ethereal.mob_light()
+	spec_updatehealth(ethereal)
 
 /datum/species/ethereal/on_species_loss(mob/living/carbon/human/C, datum/species/new_species, pref_load)
-	.=..()
-	C.set_light(0)
+	QDEL_NULL(ethereal_light)
+	return ..()
 
 /datum/species/ethereal/random_name(gender,unique,lastname)
 	if(unique)
@@ -71,15 +83,16 @@
 	return randname
 
 /datum/species/ethereal/spec_updatehealth(mob/living/carbon/human/H)
-	.=..()
+	. = ..()
 	if(H.stat != DEAD && !EMPeffect)
 		var/healthpercent = max(H.health, 0) / 100
 		if(!emageffect)
 			current_color = rgb(r2 + ((r1-r2)*healthpercent), g2 + ((g1-g2)*healthpercent), b2 + ((b1-b2)*healthpercent))
-		H.set_light(1 + (3 * healthpercent), 1 + (2 * healthpercent), current_color)
+		ethereal_light.set_light_range_power_color(1 + (2 * healthpercent), 1 + (1 * healthpercent), current_color)
+		ethereal_light.set_light_on(TRUE)
 		fixed_mut_color = copytext_char(current_color, 2)
 	else
-		H.set_light(0)
+		ethereal_light.set_light_on(FALSE)
 		fixed_mut_color = rgb(128,128,128)
 	H.update_body()
 

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

@@ -427,7 +427,7 @@
 /datum/species/jelly/luminescent/proc/update_glow(mob/living/carbon/C, intensity)
 	if(intensity)
 		glow_intensity = intensity
-	glow.set_light(glow_intensity, glow_intensity, C.dna.features["mcolor"])
+	glow.set_light_range_power_color(glow_intensity, glow_intensity, C.dna.features["mcolor"])
 
 /obj/effect/dummy/luminescent_glow
 	name = "luminescent glow"
@@ -435,6 +435,8 @@
 	icon_state = "nothing"
 	light_color = "#FFFFFF"
 	light_range = LUMINESCENT_DEFAULT_GLOW
+	light_system = MOVABLE_LIGHT
+	light_power = 2.5
 
 /obj/effect/dummy/luminescent_glow/Initialize()
 	. = ..()

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

@@ -211,9 +211,8 @@
 /obj/item/light_eater/proc/disintegrate(obj/item/O)
 	if(istype(O, /obj/item/pda))
 		var/obj/item/pda/PDA = O
-		PDA.set_light(0)
-		PDA.fon = FALSE
-		PDA.f_lum = 0
+		PDA.set_light_on(FALSE)
+		PDA.set_light_range(0) //It won't be turning on again.
 		PDA.update_icon()
 		visible_message(span_danger("The light in [PDA] shorts out!"))
 	else

code/modules/mob/living/silicon/ai/life.dm

@@ -47,8 +47,8 @@
 
 		if(!lacks_power())
 			var/area/home = get_area(src)
-			if(home.powered(EQUIP))
-				home.use_power(1000, EQUIP)
+			if(home.powered(AREA_USAGE_EQUIP))
+				home.use_power(1000, AREA_USAGE_EQUIP)
 
 			if(aiRestorePowerRoutine >= POWER_RESTORATION_SEARCH_APC)
 				ai_restore_power()

code/modules/mob/living/silicon/robot/robot.dm

@@ -10,6 +10,8 @@
 	has_limbs = 1
 	hud_type = /datum/hud/robot
 	blocks_emissive = EMISSIVE_BLOCK_GENERIC
+	light_system = MOVABLE_LIGHT
+	light_on = FALSE
 
 	var/custom_name = ""
 	var/braintype = "Cyborg"
@@ -795,17 +797,17 @@
 	//if both lamp is enabled AND the update_color flag is on, keep the lamp on. Otherwise, if anything listed is true, disable the lamp.
 	if(!(update_color && lamp_enabled) && (turn_off || lamp_enabled || update_color || !lamp_functional || stat || low_power_mode))
 		if(lamp_functional && stat != DEAD)
-			set_light(l_power = TRUE) //If the lamp isn't broken and borg isn't dead, doomsday borgs cannot disable their light fully.
-			set_light(l_color = "#FF0000") //This should only matter for doomsday borgs, as any other time the lamp will be off and the color not seen
-			set_light(l_range = 1) //Again, like above, this only takes effect when the light is forced on by doomsday mode.
-		set_light(l_power = FALSE)
+			set_light_on(TRUE) //If the lamp isn't broken and borg isn't dead, doomsday borgs cannot disable their light fully.
+			set_light_color("#FF0000") //This should only matter for doomsday borgs, as any other time the lamp will be off and the color not seen
+			set_light_range(1) //Again, like above, this only takes effect when the light is forced on by doomsday mode.
+		set_light_on(FALSE)
 		lamp_enabled = FALSE
 		lampButton?.update_icon()
 		update_icons()
 		return
-	set_light(l_range = lamp_intensity)
-	set_light(l_color = lamp_color)
-	set_light(l_power = TRUE)
+	set_light_range(lamp_intensity)
+	set_light_color(lamp_color)
+	set_light_on(TRUE)
 	lamp_enabled = TRUE
 	lampButton?.update_icon()
 	update_icons()

code/modules/mob/living/simple_animal/bot/bot.dm

@@ -4,8 +4,6 @@
 	layer = MOB_LAYER
 	gender = NEUTER
 	mob_biotypes = list(MOB_ROBOTIC)
-	light_range = 3
-	stop_automated_movement = 1
 	wander = 0
 	healable = 0
 	damage_coeff = list(BRUTE = 1, BURN = 1, TOX = 0, CLONE = 0, STAMINA = 0, OXY = 0)
@@ -23,6 +21,9 @@
 	bubble_icon = "machine"
 	speech_span = SPAN_ROBOT
 	faction = list("neutral", "silicon" , "turret")
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 0.9
 
 	var/obj/machinery/bot_core/bot_core = null
 	var/bot_core_type = /obj/machinery/bot_core
@@ -128,7 +129,7 @@
 		return FALSE
 	on = TRUE
 	update_mobility()
-	set_light(initial(light_range))
+	set_light_on(on)
 	update_icon()
 	diag_hud_set_botstat()
 	return TRUE
@@ -136,7 +137,7 @@
 /mob/living/simple_animal/bot/proc/turn_off()
 	on = FALSE
 	update_mobility()
-	set_light(0)
+	set_light_on(on)
 	bot_reset() //Resets an AI's call, should it exist.
 	update_icon()
 

code/modules/mob/living/simple_animal/guardian/guardian.dm

@@ -38,6 +38,9 @@ GLOBAL_LIST_EMPTY(parasites) //all currently existing/living guardians
 	melee_damage_upper = 15
 	butcher_results = list(/obj/item/ectoplasm = 1)
 	AIStatus = AI_OFF
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_on = FALSE
 	hud_type = /datum/hud/guardian
 	dextrous_hud_type = /datum/hud/dextrous/guardian //if we're set to dextrous, account for it.
 	var/list/guardian_overlays[GUARDIAN_TOTAL_LAYERS]
@@ -338,12 +341,12 @@ GLOBAL_LIST_EMPTY(parasites) //all currently existing/living guardians
 	to_chat(src, "<span class='danger'><B>You don't have another mode!</span></B>")
 
 /mob/living/simple_animal/hostile/guardian/proc/ToggleLight()
-	if(light_range<3)
+	if(!light_on)
 		to_chat(src, span_notice("You activate your light."))
-		set_light(3)
+		set_light_on(TRUE)
 	else
 		to_chat(src, span_notice("You deactivate your light."))
-		set_light(0)
+		set_light_on(FALSE)
 
 /mob/living/simple_animal/hostile/guardian/verb/ShowType()
 	set name = "Check Guardian Type"

code/modules/mob/living/simple_animal/hostile/hivebot.dm

@@ -60,7 +60,7 @@
 	QDEL_NULL(alert_light)
 	if(a_intent != INTENT_HELP)
 		icon_state = "[initial(icon_state)]_attack"
-		alert_light = mob_light(COLOR_RED_LIGHT, 6, 0.4)
+		alert_light = mob_light(6, 0.4, COLOR_RED_LIGHT)
 	else
 		icon_state = initial(icon_state)
 

code/modules/mob/living/simple_animal/hostile/megafauna/colossus.dm

@@ -234,6 +234,7 @@ Difficulty: Very Hard
 	icon = 'icons/effects/effects.dmi'
 	icon_state = "at_shield2"
 	layer = FLY_LAYER
+	light_system = MOVABLE_LIGHT
 	light_range = 2
 	duration = 8
 	var/target

code/modules/mob/living/simple_animal/hostile/megafauna/swarmer.dm

@@ -62,6 +62,7 @@ GLOBAL_LIST_INIT(AISwarmerCapsByType, list(/mob/living/simple_animal/hostile/swa
 	var/call_help_cooldown = 0
 	var/call_help_cooldown_amt = 150 //Deciseconds between calling swarmers to help us when attacked
 	var/static/list/swarmer_caps
+	
 
 /mob/living/simple_animal/hostile/megafauna/swarmer_swarm_beacon/Initialize()
 	. = ..()

code/modules/mob/living/simple_animal/hostile/mining_mobs/basilisk.dm

@@ -101,6 +101,7 @@
 	icon_dead = "watcher_magmawing_dead"
 	maxHealth = 235 //Compensate for the lack of slowdown on projectiles with a bit of extra health
 	health = 235
+	light_system = MOVABLE_LIGHT
 	light_range = 3
 	light_power = 2.5
 	light_color = LIGHT_COLOR_LAVA

code/modules/mob/living/simple_animal/hostile/retaliate/ghost.dm

@@ -31,6 +31,9 @@
 	movement_type = FLYING
 	pressure_resistance = 300
 	gold_core_spawnable = NO_SPAWN //too spooky for science
+	light_system = MOVABLE_LIGHT
+	light_range = 1 // same glowing as visible player ghosts
+	light_power = 2
 	var/ghost_hair_style
 	var/ghost_hair_color
 	var/mutable_appearance/ghost_hair
@@ -42,7 +45,6 @@
 /mob/living/simple_animal/hostile/retaliate/ghost/Initialize()
 	. = ..()
 	give_hair()
-	set_light(1, 2) // same glowing as visible player ghosts
 	if(random)
 		switch(rand(0,1))
 			if(0)

code/modules/modular_computers/computers/item/computer.dm

@@ -55,6 +55,12 @@
 	max_integrity = 100
 	armor = list(MELEE = 0, BULLET = 20, LASER = 20, ENERGY = 100, BOMB = 0, BIO = 100, RAD = 100, FIRE = 0, ACID = 0)
 
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 0.6
+	light_color = "#FFFFFF"
+	light_on = FALSE
+
 	/// List of "connection ports" in this computer and the components with which they are plugged
 	var/list/all_components = list()
 	/// Lazy List of extra hardware slots that can be used modularly.
@@ -67,12 +73,10 @@
 	var/obj/physical = null
 	///If the computer has a flashlight/LED light/what-have-you installed
 	var/has_light = FALSE
-	///If that light is enabled
-	var/light_on = FALSE
 	///The brightness of that light
 	var/comp_light_luminosity = 3
 	///The color of that light
-	var/comp_light_color
+	var/comp_light_color = "#FFFFFF"
 
 	// Preset Stuff
 	var/list/starting_components = list()
@@ -88,7 +92,8 @@
 	START_PROCESSING(SSobj, src)
 	if(!physical)
 		physical = src
-	comp_light_color = "#FFFFFF"
+	set_light_color(comp_light_color)
+	set_light_range(comp_light_luminosity)
 	idle_threads = list()
 	install_starting_components()
 	install_starting_files()
@@ -503,6 +508,34 @@
 	update_icon()
 	play_computer_sound(shutdown_sound, get_clamped_volume(), FALSE)
 
+/**
+  * Toggles the computer's flashlight, if it has one.
+  *
+  * Called from ui_act(), does as the name implies.
+  * It is seperated from ui_act() to be overwritten as needed.
+*/
+/obj/item/modular_computer/proc/toggle_flashlight()
+	if(!has_light)
+		return FALSE
+	set_light_on(!light_on)
+	update_icon()
+	return TRUE
+
+/**
+  * Sets the computer's light color, if it has a light.
+  *
+  * Called from ui_act(), this proc takes a color string and applies it.
+  * It is seperated from ui_act() to be overwritten as needed.
+  * Arguments:
+  ** color is the string that holds the color value that we should use. Proc auto-fails if this is null.
+*/
+/obj/item/modular_computer/proc/set_flashlight_color(color)
+	if(!has_light || !color)
+		return FALSE
+	comp_light_color = color
+	set_light_color(color)
+	return TRUE
+
 /obj/item/modular_computer/screwdriver_act(mob/user, obj/item/tool)
 	if(!all_components.len)
 		to_chat(user, "<span class='warning'>This device doesn't have any components installed.</span>")