[MIRROR] Overlay lighting component (#469)

* Overlay lighting component (#52413)

Sparks no longer lag, projectile beams move super smoothly, same with mobs and whatnot. This also allows for easy expansion into directional lights, field-of-view, wee-woo rotating lights or whatever.

It does have a downside: things right-clicked or checked through the alt+click tab will show the light overlay:


This is a BYOND limitation, very well worth it IMO.

🆑
add: Smooth movable lighting system implemented. Projectiles, sparks, thrown flashlights or moving mobs with lights should be much smoother and less laggy.
balance: Light sources no longer stack in range, though they still do in intensity.
/🆑

* Overlay lighting component

Co-authored-by: Rohesie <rohesie@gmail.com>

code/__DEFINES/dcs/signals.dm

@@ -173,6 +173,8 @@
 #define COMSIG_ATOM_SET_LIGHT_COLOR "atom_set_light_color"
 ///Called right before the atom changes the value of light_on to a different one, from base atom/set_light_on(): (new_value)
 #define COMSIG_ATOM_SET_LIGHT_ON "atom_set_light_on"
+///Called right before the atom changes the value of light_flags to a different one, from base atom/set_light_flags(): (new_value)
+#define COMSIG_ATOM_SET_LIGHT_FLAGS "atom_set_light_flags"
 ///called for each movable in a turf contents on /turf/zImpact(): (atom/movable/A, levels)
 #define COMSIG_ATOM_INTERCEPT_Z_FALL "movable_intercept_z_impact"
 ///called on a movable (NOT living) when someone starts pulling it (atom/movable/puller, state, force)
@@ -274,6 +276,14 @@
 #define COMSIG_MOVABLE_SET_ANCHORED "movable_set_anchored"
 ///from base of atom/movable/setGrabState(): (newstate)
 #define COMSIG_MOVABLE_SET_GRAB_STATE "living_set_grab_state"
+///Called when the movable tries to change its dynamic light color setting, from base atom/movable/lighting_overlay_set_color(): (color)
+#define COMSIG_MOVABLE_LIGHT_OVERLAY_SET_RANGE "movable_light_overlay_set_color"
+///Called when the movable tries to change its dynamic light power setting, from base atom/movable/lighting_overlay_set_power(): (power)
+#define COMSIG_MOVABLE_LIGHT_OVERLAY_SET_POWER "movable_light_overlay_set_power"
+///Called when the movable tries to change its dynamic light range setting, from base atom/movable/lighting_overlay_set_range(): (range)
+#define COMSIG_MOVABLE_LIGHT_OVERLAY_SET_COLOR "movable_light_overlay_set_range"
+///Called when the movable tries to toggle its dynamic light LIGHTING_ON status, from base atom/movable/lighting_overlay_toggle_on(): (new_state)
+#define COMSIG_MOVABLE_LIGHT_OVERLAY_TOGGLE_ON "movable_light_overlay_toggle_on"
 
 // /mob signals
 

code/__DEFINES/layers.dm

@@ -110,8 +110,12 @@
 
 #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 BYOND_LIGHTING_PLANE 18

code/__DEFINES/lighting.dm

@@ -1,3 +1,13 @@
+///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)
+
 //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/mobs.dm

@@ -373,3 +373,6 @@
 #define EYE_CONTACT_RANGE	5
 
 #define SILENCE_RANGED_MESSAGE (1<<0)
+
+///Swarmer flags
+#define SWARMER_LIGHT_ON (1<<0)

code/_onclick/hud/plane_master.dm

@@ -79,8 +79,9 @@
 
 /obj/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.
@@ -104,7 +105,6 @@
   * Always masks the light plane, isn't blocked by anything. Use for on mob glows,
   * magic stuff, etc.
   */
-
 /obj/screen/plane_master/emissive_unblockable
 	name = "unblockable emissive plane master"
 	plane = EMISSIVE_UNBLOCKABLE_PLANE
@@ -145,3 +145,11 @@
 	appearance_flags = PLANE_MASTER
 	blend_mode = BLEND_OVERLAY
 	alpha = 0
+
+/obj/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/datums/components/overlay_lighting.dm

@@ -0,0 +1,362 @@
+///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/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)
+	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/t in affected_turfs)
+		var/turf/lit_turf = t
+		lit_turf.dynamic_lumcount -= 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 += 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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	visible_mask.color = new_color
+
+
+///Toggles the light on and off.
+/datum/component/overlay_lighting/proc/on_toggle(atom/source, new_value)
+	SIGNAL_HANDLER
+	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)
+	SIGNAL_HANDLER
+	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)
+
+
+///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)
+	if(lum_power == new_lum_power)
+		return
+	. = lum_power
+	lum_power = new_lum_power
+	var/difference = . - lum_power
+	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

@@ -209,7 +209,8 @@
 		return
 	var/power = GET_MUTATION_POWER(src)
 
-	glowth.set_light(range * power, glow, glow_color)
+	glowth.set_light_range_power_color(range * power, glow, glow_color)
+
 
 /// Returns the color for the glow effect
 /datum/mutation/human/glow/proc/glow_color()

code/game/atoms.dm

@@ -92,6 +92,8 @@
 	/// Last appearance of the atom for demo saving purposes
 	var/image/demo_last_appearance
 
+	///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.
@@ -100,6 +102,8 @@
 	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.
@@ -204,7 +208,7 @@
 	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 (length(smoothing_groups))

code/game/atoms_movable.dm

@@ -54,6 +54,11 @@
 	///Used for the calculate_adjacencies proc for icon smoothing.
 	var/can_be_unanchored = FALSE
 
+	///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)
 	. = ..()
@@ -66,6 +71,8 @@
 			vis_contents += em_block
 	if(opacity)
 		AddElement(/datum/element/light_blocking)
+	if(light_system == MOVABLE_LIGHT)
+		AddComponent(/datum/component/overlay_lighting)
 
 
 /atom/movable/Destroy(force)

code/game/machinery/dance_machine.dm

@@ -185,60 +185,28 @@
 	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.set_light_color(COLOR_SOFT_RED)
-			L.set_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), COLOR_SOFT_RED)
 			continue
 		if(t.x == cen.x && t.y < cen.y)
-			var/obj/item/flashlight/spotlight/L = new /obj/item/flashlight/spotlight(t)
-			L.set_light_color(LIGHT_COLOR_PURPLE)
-			L.set_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.set_light_color(LIGHT_COLOR_YELLOW)
-			L.set_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.set_light_color(LIGHT_COLOR_GREEN)
-			L.set_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.set_light_color(LIGHT_COLOR_ORANGE)
-			L.set_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.set_light_color(LIGHT_COLOR_CYAN)
-			L.set_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.set_light_color(LIGHT_COLOR_BLUEGREEN)
-			L.set_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.set_light_color(LIGHT_COLOR_BLUE)
-			L.set_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
@@ -270,61 +238,80 @@
 		sleep(7)
 	if(selection.song_name == "Engineering's Ultimate High-Energy Hustle")
 		sleep(280)
-	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 == COLOR_SOFT_RED)
-				glow.set_light_color(LIGHT_COLOR_BLUE)
-				glow.set_light_power(glow.light_power * 1.48)
-				glow.set_light_range(0)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_BLUE)
-				glow.set_light_color(LIGHT_COLOR_GREEN)
-				glow.set_light_range(glow.range * DISCO_INFENO_RANGE)
-				glow.set_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.set_light_color(LIGHT_COLOR_ORANGE)
-				glow.set_light_power(glow.light_power * 0.5)
-				glow.set_light_range(0)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_ORANGE)
-				glow.set_light_color(LIGHT_COLOR_PURPLE)
-				glow.set_light_power(glow.light_power * 2.27)
-				glow.set_light_range(glow.range * DISCO_INFENO_RANGE)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_PURPLE)
-				glow.set_light_color(LIGHT_COLOR_BLUEGREEN)
-				glow.set_light_power(glow.light_power * 0.44)
-				glow.set_light_range(0)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_BLUEGREEN)
-				glow.set_light_color(LIGHT_COLOR_YELLOW)
-				glow.set_light_range(glow.range * DISCO_INFENO_RANGE)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_YELLOW)
-				glow.set_light_color(LIGHT_COLOR_CYAN)
-				glow.set_light_range(0)
-				glow.update_light()
-				continue
-			if(glow.light_color == LIGHT_COLOR_CYAN)
-				glow.set_light_color(COLOR_SOFT_RED)
-				glow.set_light_power(glow.light_power * 0.68)
-				glow.set_light_range(glow.range * DISCO_INFENO_RANGE)
-				glow.update_light()
-				continue
+			switch(glow.light_color)
+				if(COLOR_SOFT_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, COLOR_SOFT_RED)
+						glow.set_light_on(TRUE)
+					else
+						glow.set_light_on(FALSE)
+						glow.set_light_color(COLOR_SOFT_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/flasher.dm

@@ -25,6 +25,9 @@
 	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
@@ -35,6 +38,7 @@
 	else
 		bulb = new(src)
 
+
 /obj/machinery/flasher/connect_to_shuttle(obj/docking_port/mobile/port, obj/docking_port/stationary/dock, idnum, override=FALSE)
 	id = "[idnum][id]"
 
@@ -107,7 +111,9 @@
 
 	playsound(src.loc, 'sound/weapons/flash.ogg', 100, TRUE)
 	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 +132,10 @@
 	return 1
 
 
+/obj/machinery/flasher/proc/flash_end()
+	set_light_on(FALSE)
+
+
 /obj/machinery/flasher/emp_act(severity)
 	. = ..()
 	if(!(machine_stat & (BROKEN|NOPOWER)) && !(. & EMP_PROTECT_SELF))

code/game/mecha/combat/durand.dm

@@ -13,18 +13,19 @@
 	wreckage = /obj/structure/mecha_wreckage/durand
 	var/obj/durand_shield/shield
 
+
 /obj/mecha/combat/durand/Initialize()
-	shield = new/obj/durand_shield
-	shield.chassis = src
-	shield.layer = layer
+	. = ..()
+	shield = new /obj/durand_shield(loc, src, layer, dir)
 	RegisterSignal(src, COMSIG_MECHA_ACTION_ACTIVATE, .proc/relay)
 	RegisterSignal(src, COMSIG_PROJECTILE_PREHIT, .proc/prehit)
-	. = ..()
+
 
 /obj/mecha/combat/durand/Destroy()
 	if(shield)
-		qdel(shield)
-	. = ..()
+		QDEL_NULL(shield)
+	return ..()
+
 
 /obj/mecha/combat/durand/GrantActions(mob/living/user, human_occupant = 0)
 	..()
@@ -43,7 +44,7 @@
 	. = ..()
 	if(shield)
 		shield.forceMove(loc)
-		shield.dir = dir
+		shield.setDir(dir)
 
 /obj/mecha/combat/durand/forceMove(turf/T)
 	. = ..()
@@ -59,11 +60,9 @@
 	SIGNAL_HANDLER
 
 	if(!shield) //if the shield somehow got deleted
-		shield = new/obj/durand_shield
-		shield.chassis = src
-		shield.layer = layer
-		shield.forceMove(loc)
-	shield.dir = dir
+		stack_trace("Durand triggered relay without a shield")
+		shield = new /obj/durand_shield(loc, src, layer)
+	shield.setDir(dir)
 	SEND_SIGNAL(shield, COMSIG_MECHA_ACTION_ACTIVATE, source, signal_args)
 
 //Redirects projectiles to the shield if defense_check decides they should be blocked and returns true.
@@ -143,17 +142,28 @@ own integrity back to max. Shield is automatically dropped if we run out of powe
 	max_integrity = 10000
 	obj_integrity = 10000
 	anchored = TRUE
+	light_system = MOVABLE_LIGHT
+	light_range = MINIMUM_USEFUL_LIGHT_RANGE
+	light_power = 5
+	light_color = LIGHT_COLOR_ELECTRIC_CYAN
+	light_on = FALSE
 	var/obj/mecha/combat/durand/chassis ///Our link back to the durand
 	var/switching = FALSE ///To keep track of things during the animation
 
-/obj/durand_shield/Initialize()
+
+/obj/durand_shield/Initialize(mapload, _chassis, _layer, _dir)
 	. = ..()
+	chassis = _chassis
+	layer = _layer
+	setDir(_dir)
 	RegisterSignal(src, COMSIG_MECHA_ACTION_ACTIVATE, .proc/activate)
 
+
 /obj/durand_shield/Destroy()
 	if(chassis)
 		chassis.shield = null
-	. = ..()
+		chassis = null
+	return ..()
 
 /**Handles activating and deactivating the shield. This proc is called by a signal sent from the mech's action button
 and relayed by the mech itself. The "forced" variabe, signal_args[1], will skip the to-pilot text and is meant for when
@@ -179,11 +189,12 @@ the shield is disabled by means other than the action button (like running out o
 		chassis.log_message("defense mode state changed -- now [chassis.defense_mode?"enabled":"disabled"].", LOG_MECHA)
 	chassis.defense_action.UpdateButtonIcon()
 
+	set_light_on(chassis.defense_mode)
+
 	if(chassis.defense_mode)
 		invisibility = 0
 		flick("shield_raise", src)
 		playsound(src, 'sound/mecha/mech_shield_raise.ogg', 50, FALSE)
-		set_light(l_range = MINIMUM_USEFUL_LIGHT_RANGE	, l_power = 5, l_color = "#00FFFF")
 		addtimer(CALLBACK(src, .proc/shield_icon_enable), 3)
 	else
 		flick("shield_drop", src)
@@ -195,7 +206,6 @@ the shield is disabled by means other than the action button (like running out o
 	icon_state = "shield"
 
 /obj/durand_shield/proc/shield_icon_reset()
-	set_light(0)
 	icon_state = "shield_null"
 	invisibility = INVISIBILITY_MAXIMUM //no showing on right-click
 

code/game/mecha/mecha.dm

@@ -10,6 +10,8 @@
 	infra_luminosity = 15 //byond implementation is bugged.
 	force = 5
 	flags_1 = HEAR_1
+	light_system = MOVABLE_LIGHT
+	light_on = FALSE
 	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
 	var/mob/living/carbon/occupant = null

code/game/mecha/mecha_actions.dm

@@ -112,11 +112,10 @@
 		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("<span class='notice'>Toggled lights [chassis.lights?"on":"off"].</span>")
 	chassis.log_message("Toggled lights [chassis.lights?"on":"off"].", LOG_MECHA)
 	UpdateButtonIcon()

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

@@ -20,8 +20,9 @@
 	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
 
 /obj/effect/particle_effect/sparks/Initialize()

code/game/objects/effects/misc.dm

@@ -75,13 +75,19 @@
 	name = "lighting fx obj"
 	desc = "Tell a coder if you're seeing this."
 	icon_state = "nothing"
+	light_system = MOVABLE_LIGHT
 	light_range = MINIMUM_USEFUL_LIGHT_RANGE
 	light_color = COLOR_WHITE
 	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

@@ -64,3 +64,14 @@
 
 	layer = ATMOS_GROUP_LAYER
 	plane = ATMOS_GROUP_PLANE
+
+/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/cigs_lighters.dm

@@ -621,7 +621,11 @@ CIGARETTE PACKETS ARE IN FANCY.DM
 	resistance_flags = FIRE_PROOF
 	grind_results = list(/datum/reagent/iron = 1, /datum/reagent/fuel = 5, /datum/reagent/fuel/oil = 5)
 	custom_price = 55
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 0.6
 	light_color = LIGHT_COLOR_FIRE
+	light_on = FALSE
 	var/lit = 0
 	var/fancy = TRUE
 	var/overlay_state
@@ -667,6 +671,8 @@ CIGARETTE PACKETS ARE IN FANCY.DM
 		. = "<span class='rose'>With a single flick of [user.p_their()] wrist, [user] smoothly lights [A] with [src]. Damn [user.p_theyre()] cool.</span>"
 
 /obj/item/lighter/proc/set_lit(new_lit)
+	if(lit == new_lit)
+		return
 	lit = new_lit
 	if(lit)
 		force = 5
@@ -674,15 +680,14 @@ CIGARETTE PACKETS ARE IN FANCY.DM
 		hitsound = 'sound/items/welder.ogg'
 		attack_verb_continuous = list("burns", "sings")
 		attack_verb_simple = list("burn", "sing")
-		set_light(1)
 		START_PROCESSING(SSobj, src)
 	else
 		hitsound = "swing_hit"
 		force = 0
 		attack_verb_continuous = null //human_defense.dm takes care of it
 		attack_verb_simple = null
-		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

@@ -26,7 +26,11 @@ GLOBAL_LIST_EMPTY(PDAs)
 	actions_types = list(/datum/action/item_action/toggle_light)
 	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
@@ -49,8 +53,6 @@ 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/tnote = null //Current Texts
@@ -106,8 +108,6 @@ GLOBAL_LIST_EMPTY(PDAs)
 
 /obj/item/pda/Initialize()
 	. = ..()
-	if(fon)
-		set_light(f_lum)
 
 	GLOB.PDAs += src
 	if(default_cartridge)
@@ -175,7 +175,7 @@ GLOBAL_LIST_EMPTY(PDAs)
 	if(inserted_item)
 		overlay.icon_state = "insert_overlay"
 		. += new /mutable_appearance(overlay)
-	if(fon)
+	if(light_on)
 		overlay.icon_state = "light_overlay"
 		. += new /mutable_appearance(overlay)
 	if(pai)
@@ -311,7 +311,7 @@ GLOBAL_LIST_EMPTY(PDAs)
 					if (cartridge.access & CART_DRONEPHONE)
 						dat += "<li><a href='byond://?src=[REF(src)];choice=Drone Phone'>[PDAIMG(dronephone)]Drone Phone</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
@@ -835,12 +835,10 @@ GLOBAL_LIST_EMPTY(PDAs)
 /obj/item/pda/proc/toggle_light(mob/user)
 	if(issilicon(user) || !user.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

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

@@ -43,7 +43,7 @@
 /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

@@ -13,9 +13,12 @@
 	slot_flags = ITEM_SLOT_BELT
 	custom_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()
 	. = ..()
@@ -23,16 +26,13 @@
 		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)
+
 
 /obj/item/flashlight/attack_self(mob/user)
 	on = !on
@@ -64,7 +64,7 @@
 			to_chat(user, "<span class='warning'>[M] doesn't have a head!</span>")
 			return
 
-		if(flashlight_power < 1)
+		if(light_power < 1)
 			to_chat(user, "<span class='warning'>\The [src] isn't bright enough to see anything!</span> ")
 			return
 
@@ -169,7 +169,7 @@
 	inhand_icon_state = ""
 	worn_icon_state = "pen"
 	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)
@@ -217,7 +217,7 @@
 	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
@@ -229,7 +229,7 @@
 	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
 	custom_materials = null
@@ -265,7 +265,7 @@
 	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"
 	inhand_icon_state = "flare"
 	worn_icon_state = "flare"
@@ -335,7 +335,7 @@
 	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"
 	inhand_icon_state = "torch"
 	lefthand_file = 'icons/mob/inhands/items_lefthand.dmi'
@@ -351,19 +351,19 @@
 	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"
 	inhand_icon_state = "syndilantern"
-	brightness_on = 10
+	light_range = 10
 
 /obj/item/flashlight/lantern/jade
 	name = "jade lantern"
@@ -381,7 +381,7 @@
 	w_class = WEIGHT_CLASS_SMALL
 	slot_flags = ITEM_SLOT_BELT
 	custom_materials = null
-	brightness_on = 6 //luminosity when on
+	light_range = 6 //luminosity when on
 
 /obj/item/flashlight/emp
 	var/emp_max_charges = 4
@@ -442,7 +442,7 @@
 	desc = "A military-grade glowstick."
 	custom_price = 50
 	w_class = WEIGHT_CLASS_SMALL
-	brightness_on = 4
+	light_range = 4
 	color = LIGHT_COLOR_GREEN
 	icon_state = "glowstick"
 	inhand_icon_state = "glowstick"
@@ -450,14 +450,17 @@
 	grind_results = list(/datum/reagent/phenol = 15, /datum/reagent/hydrogen = 10, /datum/reagent/oxygen = 5) //Meth-in-a-stick
 	var/fuel = 0
 
+
 /obj/item/flashlight/glowstick/Initialize()
 	fuel = rand(1600, 2000)
 	set_light_color(color)
-	. = ..()
+	return ..()
+
 
 /obj/item/flashlight/glowstick/Destroy()
 	STOP_PROCESSING(SSobj, src)
-	. = ..()
+	return ..()
+
 
 /obj/item/flashlight/glowstick/process()
 	fuel = max(fuel - 1, 0)
@@ -476,13 +479,13 @@
 	if(!fuel)
 		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)
 		inhand_icon_state = "glowstick-on"
-		set_light(brightness_on)
+		set_light_on(TRUE)
 	else
 		icon_state = "glowstick"
 		cut_overlays()
@@ -549,30 +552,56 @@
 	name = "disco light"
 	desc = "Groovy..."
 	icon_state = null
-	light_color = COLOR_WHITE
-	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"
 	inhand_icon_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/dualsaber.dm

@@ -16,7 +16,10 @@
 	w_class = WEIGHT_CLASS_SMALL
 	hitsound = "swing_hit"
 	armour_penetration = 35
+	light_system = MOVABLE_LIGHT
+	light_range = 6 //TWICE AS BRIGHT AS A REGULAR ESWORD
 	light_color = LIGHT_COLOR_ELECTRIC_GREEN
+	light_on = FALSE
 	attack_verb_continuous = list("attacks", "slashes", "stabs", "slices", "tears", "lacerates", "rips", "dices", "cuts")
 	attack_verb_simple = list("attack", "slash", "stab", "slice", "tear", "lacerate", "rip", "dice", "cut")
 	block_chance = 75
@@ -29,7 +32,6 @@
 	var/saber_color = "green"
 	var/two_hand_force = 34
 	var/hacked = FALSE
-	var/brightness_on = 6 //TWICE AS BRIGHT AS A REGULAR ESWORD
 	var/list/possible_colors = list("red", "blue", "green", "purple")
 	var/wielded = FALSE // track wielded status on item
 
@@ -50,7 +52,8 @@
 	w_class = w_class_on
 	hitsound = 'sound/weapons/blade1.ogg'
 	START_PROCESSING(SSobj, src)
-	set_light(brightness_on)
+	set_light_on(TRUE)
+
 
 /// Triggered on unwield of two handed item
 /// switch hitsounds
@@ -61,7 +64,8 @@
 	w_class = initial(w_class)
 	hitsound = "swing_hit"
 	STOP_PROCESSING(SSobj, src)
-	set_light(0)
+	set_light_on(FALSE)
+
 
 /obj/item/dualsaber/get_sharpness()
 	return wielded * sharpness

code/game/objects/items/flamethrower.dm

@@ -15,6 +15,8 @@
 	custom_materials = list(/datum/material/iron=500)
 	resistance_flags = FIRE_PROOF
 	trigger_guard = TRIGGER_GUARD_NORMAL
+	light_system = MOVABLE_LIGHT
+	light_on = FALSE
 	var/status = FALSE
 	var/lit = FALSE	//on or off
 	var/operating = FALSE//cooldown
@@ -165,16 +167,15 @@
 	to_chat(user, "<span class='notice'>You [lit ? "extinguish" : "ignite"] [src]!</span>")
 	lit = !lit
 	if(lit)
-		set_light(1)
 		playsound(loc, acti_sound, 50, TRUE)
 		START_PROCESSING(SSobj, src)
 		if(!warned_admins)
 			message_admins("[ADMIN_LOOKUPFLW(user)] has lit a flamethrower.")
 			warned_admins = TRUE
 	else
-		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

@@ -14,7 +14,7 @@
 		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, 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)
@@ -82,7 +82,7 @@
 		return
 	do_sparks(rand(5, 9), FALSE, src)
 	playsound(flashbang_turf, 'sound/weapons/flashbang.ogg', 50, TRUE, 8, 0.9)
-	new /obj/effect/dummy/lighting_obj (flashbang_turf, COLOR_WHITE, (flashbang_range + 2), 2, 1)
+	new /obj/effect/dummy/lighting_obj (flashbang_turf, flashbang_range + 2, 2, COLOR_WHITE, 1)
 	for(var/mob/living/M in get_hearers_in_view(flashbang_range, flashbang_turf))
 		pop(get_turf(M), M)
 	qdel(src)

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

@@ -15,7 +15,7 @@
 		return
 	do_sparks(rand(5, 9), FALSE, src)
 	playsound(flashbang_turf, 'sound/effects/screech.ogg', 100, TRUE, 8, 0.9)
-	new /obj/effect/dummy/lighting_obj (flashbang_turf, LIGHT_COLOR_PURPLE, (flashbang_range + 2), 4, 2)
+	new /obj/effect/dummy/lighting_obj (flashbang_turf, flashbang_range + 2, 4, LIGHT_COLOR_PURPLE, 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/sword_color
 
 /obj/item/melee/transforming/energy/Initialize()
 	. = ..()
 	if(active)
-		set_light(brightness_on)
 		START_PROCESSING(SSobj, src)
 
 /obj/item/melee/transforming/energy/Destroy()
@@ -40,10 +42,10 @@
 			if(sword_color)
 				icon_state = "sword[sword_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/get_temperature()
 	return active * heat
@@ -167,7 +169,6 @@
 	if(hacked)
 		var/set_color = pick(possible_colors)
 		set_light_color(possible_colors[set_color])
-		update_light()
 
 /obj/item/melee/transforming/energy/sword/saber/red
 	possible_colors = list("red" = COLOR_SOFT_RED)

code/game/objects/items/pitchfork.dm

@@ -45,10 +45,11 @@
 	desc = "A red pitchfork, it looks like the work of the devil."
 	force = 19
 	throwforce = 24
+	light_system = MOVABLE_LIGHT
+	light_range = 3
+	light_power = 6
+	light_color = COLOR_SOFT_RED
 
-/obj/item/pitchfork/demonic/Initialize()
-	. = ..()
-	set_light(3,6,COLOR_SOFT_RED)
 
 /obj/item/pitchfork/demonic/ComponentInitialize()
 	. = ..()

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

@@ -16,7 +16,11 @@
 	usesound = list('sound/items/welder.ogg', 'sound/items/welder2.ogg')
 	drop_sound = 'sound/items/handling/weldingtool_drop.ogg'
 	pickup_sound =  'sound/items/handling/weldingtool_pickup.ogg'
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 0.75
 	light_color = LIGHT_COLOR_FIRE
+	light_on = FALSE
 	throw_speed = 3
 	throw_range = 5
 	w_class = WEIGHT_CLASS_SMALL
@@ -28,12 +32,12 @@
 	wound_bonus = 10
 	bare_wound_bonus = 15
 	custom_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/burned_fuel_for = 0	//when fuel was last removed
 	var/acti_sound = 'sound/items/welderactivate.ogg'
 	var/deac_sound = 'sound/items/welderdeactivate.ogg'
@@ -47,7 +51,7 @@
 /obj/item/weldingtool/ComponentInitialize()
 	. = ..()
 	AddElement(/datum/element/update_icon_updates_onmob)
-	AddElement(/datum/element/tool_flash, light_intensity)
+	AddElement(/datum/element/tool_flash, light_range)
 
 /obj/item/weldingtool/update_icon_state()
 	if(welding)
@@ -158,16 +162,16 @@
 				message_admins("[ADMIN_LOOKUPFLW(user)] set [key_name_admin(L)] on fire with [src] at [AREACOORD(user)]")
 				log_game("[key_name(user)] set [key_name(L)] on fire with [src] at [AREACOORD(user)]")
 
+
 /obj/item/weldingtool/attack_self(mob/user)
 	if(src.reagents.has_reagent(/datum/reagent/toxin/plasma))
 		message_admins("[ADMIN_LOOKUPFLW(user)] activated a rigged welder at [AREACOORD(user)].")
 		explode()
 	switched_on(user)
-	if(welding)
-		set_light(light_intensity)
 
 	update_icon()
 
+
 // Ah fuck, I can't believe you've done this
 /obj/item/weldingtool/proc/handle_fuel_and_temps(used = 0, mob/living/user)
 	use(used)
@@ -194,10 +198,19 @@
 		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(0)
+		set_light_on(FALSE)
 		switched_on(user)
 		update_icon()
 		return 0
@@ -208,7 +221,7 @@
 	if(!status)
 		to_chat(user, "<span class='warning'>[src] can't be turned on while unsecured!</span>")
 		return
-	welding = !welding
+	set_welding(!welding)
 	if(welding)
 		if(get_fuel() >= 1)
 			to_chat(user, "<span class='notice'>You switch [src] on.</span>")
@@ -228,8 +241,7 @@
 
 //Switches the welder off
 /obj/item/weldingtool/proc/switched_off(mob/user)
-	welding = 0
-	set_light(0)
+	set_welding(FALSE)
 
 	force = 3
 	damtype = "brute"
@@ -335,7 +347,8 @@
 	icon = 'icons/obj/abductor.dmi'
 	icon_state = "welder"
 	toolspeed = 0.1
-	light_intensity = 0
+	light_system = NO_LIGHT_SUPPORT
+	light_range = 0
 	change_icons = 0
 
 /obj/item/weldingtool/abductor/process()
@@ -360,7 +373,7 @@
 	custom_materials = list(/datum/material/iron=70, /datum/material/glass=120)
 	change_icons = 0
 	can_off_process = 1
-	light_intensity = 1
+	light_range = 1
 	toolspeed = 0.5
 	var/last_gen = 0
 	var/nextrefueltick = 0

code/game/turfs/open/space/space.dm

@@ -57,7 +57,7 @@
 	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

@@ -38,6 +38,9 @@ GLOBAL_LIST_EMPTY(station_turfs)
 	///Icon-smoothing variable to map a diagonal wall corner with a fixed underlay.
 	var/list/fixed_underlay = null
 
+	///Lumcount added by sources other than lighting datum objects, such as the overlay lighting component.
+	var/dynamic_lumcount = 0
+
 	var/dynamic_lighting = TRUE
 
 	var/tmp/lighting_corners_initialised = FALSE

code/modules/antagonists/cult/blood_magic.dm

@@ -421,12 +421,12 @@
 		user.visible_message("<span class='warning'>[user] holds up [user.p_their()] hand, which explodes in a flash of red light!</span>", \
 							"<span class='cultitalic'>You attempt to stun [L] with the spell!</span>")
 
-		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

@@ -93,6 +93,8 @@
 	throw_speed = 1
 	throw_range = 3
 	sharpness = SHARP_EDGED
+	light_system = MOVABLE_LIGHT
+	light_range = 4
 	light_color = COLOR_RED
 	attack_verb_continuous = list("cleaves", "slashes", "tears", "lacerates", "hacks", "rips", "dices", "carves")
 	attack_verb_simple = list("cleave", "slash", "tear", "lacerate", "hack", "rip", "dice", "carve")
@@ -113,12 +115,12 @@
 
 /obj/item/cult_bastard/Initialize()
 	. = ..()
-	set_light(4)
 	jaunt = new(src)
 	linked_action = new(src)
 	AddComponent(/datum/component/butchering, 50, 80)
 	AddComponent(/datum/component/two_handed, require_twohands=TRUE)
 
+
 /obj/item/cult_bastard/examine(mob/user)
 	. = ..()
 	if(contents.len)
@@ -341,7 +343,8 @@
 	icon_state = "cult_helmet"
 	inhand_icon_state = "cult_helmet"
 	armor = list("melee" = 70, "bullet" = 50, "laser" = 30,"energy" = 40, "bomb" = 30, "bio" = 30, "rad" = 30, "fire" = 40, "acid" = 75)
-	brightness_on = 0
+	light_system = NO_LIGHT_SUPPORT
+	light_range = 0
 	actions_types = list()
 
 /obj/item/clothing/suit/space/hardsuit/cult
@@ -576,7 +579,7 @@
 	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"
 	inhand_icon_state = "torch"
 	color = "#ff0000"

code/modules/assembly/flash.dm

@@ -9,8 +9,11 @@
 	throwforce = 0
 	w_class = WEIGHT_CLASS_TINY
 	custom_materials = list(/datum/material/iron = 300, /datum/material/glass = 300)
+	light_system = MOVABLE_LIGHT //Used as a flash here.
+	light_range = FLASH_LIGHT_RANGE
 	light_color = COLOR_WHITE
 	light_power = FLASH_LIGHT_POWER
+	light_on = FALSE
 	var/flashing_overlay = "flash-f"
 	var/times_used = 0 //Number of times it's been used.
 	var/burnt_out = FALSE     //Is the flash burnt out?
@@ -19,6 +22,7 @@
 	var/cooldown = 0
 	var/last_trigger = 0 //Last time it was successfully triggered.
 
+
 /obj/item/assembly/flash/suicide_act(mob/living/user)
 	if(burnt_out)
 		user.visible_message("<span class='suicide'>[user] raises \the [src] up to [user.p_their()] eyes and activates it ... but it's burnt out!</span>")
@@ -97,7 +101,8 @@
 		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)
@@ -105,6 +110,11 @@
 		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

@@ -49,9 +49,10 @@
 	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
@@ -60,6 +61,7 @@
 	var/bypassing = FALSE
 	var/visual_update_tick = 0
 
+
 /obj/effect/hotspot/Initialize(mapload, starting_volume, starting_temperature)
 	. = ..()
 	SSair.hotspots += src
@@ -147,7 +149,7 @@
 		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
@@ -210,7 +212,6 @@
 	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/clothing/head/hardhat.dm

@@ -3,18 +3,24 @@
 	desc = "A piece of headgear used in dangerous working conditions to protect the head. Comes with a built-in flashlight."
 	icon_state = "hardhat0_yellow"
 	inhand_icon_state = "hardhat0_yellow"
-	var/brightness_on = 4 //luminosity when on
-	var/on = FALSE
-	var/hat_type = "yellow" //Determines used sprites: hardhat[on]_[hat_type] and hardhat[on]_[hat_type]2 (lying down sprite)
 	armor = list("melee" = 15, "bullet" = 5, "laser" = 20, "energy" = 10, "bomb" = 20, "bio" = 10, "rad" = 20, "fire" = 100, "acid" = 50, "wound" = 10) // surprisingly robust against head trauma
 	flags_inv = 0
 	actions_types = list(/datum/action/item_action/toggle_helmet_light)
 	clothing_flags = SNUG_FIT
 	resistance_flags = FIRE_PROOF
 	dynamic_hair_suffix = "+generic"
-
+	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] and hardhat[on]_[hat_type]2 (lying down sprite)
+	var/hat_type = "yellow"
+	///Whether the headlamp is on or off.
+	var/on = FALSE
+
+
 /obj/item/clothing/head/hardhat/ComponentInitialize()
 	. = ..()
 	AddElement(/datum/element/update_icon_updates_onmob)
@@ -34,10 +40,10 @@
 	icon_state = inhand_icon_state = "hardhat[on]_[hat_type]"
 
 /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"
@@ -62,7 +68,7 @@
 	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"
 	inhand_icon_state = "hardhat0_purple"
-	brightness_on = 5
+	light_range = 5
 	resistance_flags = FIRE_PROOF | ACID_PROOF
 	custom_materials = list(/datum/material/iron = 4000, /datum/material/glass = 1000, /datum/material/plastic = 3000, /datum/material/silver = 500)
 	hat_type = "purple"
@@ -102,7 +108,7 @@
 /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 = FLASH_PROTECTION_WELDER
@@ -150,7 +156,7 @@
 	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"
 	inhand_icon_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

@@ -24,6 +24,14 @@
 	if(attached_light)
 		alight = new(src)
 
+
+/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)
@@ -33,18 +41,34 @@
 	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
 
@@ -460,9 +484,7 @@
 			if(!user.transferItemToLoc(S, src))
 				return
 			to_chat(user, "<span class='notice'>You click [S] into place on [src].</span>")
-			if(S.on)
-				set_light(0)
-			attached_light = S
+			set_attached_light(S)
 			update_icon()
 			update_helmlight()
 			alight = new(src)
@@ -480,8 +502,7 @@
 		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()
@@ -501,21 +522,16 @@
 	if(user.incapacitated())
 		return
 	attached_light.on = !attached_light.on
-	to_chat(user, "<span class='notice'>You toggle the helmet-light [attached_light.on ? "on":"off"].</span>")
+	attached_light.update_brightness()
+	to_chat(user, "<span class='notice'>You toggle the helmet light [attached_light.on ? "on":"off"].</span>")
 
 	playsound(user, 'sound/weapons/empty.ogg', 100, TRUE)
 	update_helmlight()
 
 /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

@@ -52,7 +52,7 @@
 	var/damtype_on = BURN
 	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
 
@@ -98,7 +98,7 @@
 	hitsound_off = 'sound/weapons/tap.ogg'
 	damtype_on = BRUTE
 	force_on = 18 //same as epen (but much more obvious)
-	brightness_on = 3 //ditto
+	light_range = 3 //ditto
 	heat = 0
 
 /obj/item/clothing/head/hardhat/cakehat/energycake/turn_on(mob/living/user)
@@ -150,7 +150,7 @@
 	clothing_flags = SNUG_FIT
 	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
 
 /*
@@ -186,7 +186,7 @@
 	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

@@ -341,25 +341,31 @@
 	icon_state = "kindleKicks"
 	inhand_icon_state = "kindleKicks"
 	actions_types = list(/datum/action/item_action/kindle_kicks)
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 3
+	light_on = FALSE
 	var/lightCycle = 0
 	var/active = FALSE
 
+
 /obj/item/clothing/shoes/kindle_kicks/ui_action_click(mob/user, action)
 	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/kindle_kicks/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

@@ -9,8 +9,11 @@
 	inhand_icon_state = "eng_helm"
 	max_integrity = 300
 	armor = list("melee" = 10, "bullet" = 5, "laser" = 10, "energy" = 20, "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
 	var/hardsuit_type = "engineering" //Determines used sprites: hardsuit[on]-[type]
@@ -37,10 +40,8 @@
 	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()
@@ -274,7 +275,7 @@
 	resistance_flags = FIRE_PROOF
 	heat_protection = HEAD
 	armor = list("melee" = 30, "bullet" = 5, "laser" = 10, "energy" = 20, "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()
@@ -329,7 +330,7 @@
 		to_chat(user, "<span class='notice'>You switch your hardsuit to EVA mode, sacrificing speed for space protection.</span>")
 		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
@@ -338,7 +339,7 @@
 		to_chat(user, "<span class='notice'>You switch your hardsuit to combat mode and can now run at full speed.</span>")
 		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

code/modules/clothing/spacesuits/miscellaneous.dm

@@ -168,7 +168,7 @@ Contains:
 	hardsuit_type = "ert_commander"
 	armor = list("melee" = 65, "bullet" = 50, "laser" = 50, "energy" = 60, "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
 
@@ -316,7 +316,8 @@ Contains:
 	icon_state = "carp_helm"
 	inhand_icon_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()
 	flags_inv = HIDEEARS|HIDEHAIR|HIDEFACIALHAIR //facial hair will clip with the helm, this'll need a dynamic_fhair_suffix at some point.
 

code/modules/clothing/spacesuits/plasmamen.dm

@@ -45,8 +45,10 @@
 	tint = 2
 	armor = list("melee" = 0, "bullet" = 0, "laser" = 0, "energy" = 0, "bomb" = 0, "bio" = 100, "rad" = 0, "fire" = 100, "acid" = 75)
 	resistance_flags = FIRE_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
 	var/smile = FALSE
 	var/smile_color = "#FF0000"
 	var/visor_icon = "envisor"
@@ -68,9 +70,9 @@
 
 /obj/item/clothing/head/helmet/space/plasmaman/proc/toggle_welding_screen(mob/living/user)
 	if(weldingvisortoggle(user))
-		if(on)
+		if(helmet_on)
 			to_chat(user, "<span class='notice'>Your helmet's torch can't pass through your welding visor!</span>")
-			on = FALSE
+			helmet_on = FALSE
 			playsound(src, 'sound/mecha/mechmove03.ogg', 50, TRUE) //Visors don't just come from nothing
 			update_icon()
 		else
@@ -114,19 +116,19 @@
 		return TRUE
 
 /obj/item/clothing/head/helmet/space/plasmaman/attack_self(mob/user)
-	on = !on
-	icon_state = "[initial(icon_state)][on ? "-light":""]"
+	helmet_on = !helmet_on
+	icon_state = "[initial(icon_state)][helmet_on ? "-light":""]"
 	inhand_icon_state = icon_state
 	user.update_inv_head() //So the mob overlay updates
 
-	if(on)
+	if(helmet_on)
 		if(!up)
 			to_chat(user, "<span class='notice'>Your helmet's torch can't pass through your welding visor!</span>")
-			set_light(0)
+			set_light_on(FALSE)
 		else
-			set_light(brightness_on)
+			set_light_on(TRUE)
 	else
-		set_light(0)
+		set_light_on(FALSE)
 
 	for(var/X in actions)
 		var/datum/action/A=X

code/modules/hydroponics/grown/ambrosia.dm

@@ -74,6 +74,7 @@
 	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

@@ -319,8 +319,9 @@
 	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

@@ -27,6 +27,9 @@
 	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
@@ -84,47 +87,54 @@
 /atom/vv_edit_var(var_name, var_value)
 	switch (var_name)
 		if (NAMEOF(src, 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 (NAMEOF(src, 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 (NAMEOF(src, 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 = 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 = 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 = 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)
 
-/mob/living/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
-	mob_light(_color, _range, _power, _duration)
+/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/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
 
 
@@ -158,3 +168,11 @@
 	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_turf.dm

@@ -63,6 +63,8 @@
 
 	totallums = (totallums - minlum) / (maxlum - minlum)
 
+	totallums += dynamic_lumcount
+
 	return CLAMP01(totallums)
 
 // Returns a boolean whether the turf is on soft lighting.

code/modules/mining/equipment/kinetic_crusher.dm

@@ -21,13 +21,14 @@
 	sharpness = SHARP_EDGED
 	actions_types = list(/datum/action/item_action/toggle_light)
 	obj_flags = UNIQUE_RENAME
+	light_system = MOVABLE_LIGHT
+	light_range = 5
 	light_on = FALSE
 	var/list/trophies = list()
 	var/charged = TRUE
 	var/charge_time = 15
 	var/detonation_damage = 50
 	var/backstab_bonus = 30
-	var/brightness_on = 5
 	var/wielded = FALSE // track wielded status on item
 
 /obj/item/kinetic_crusher/Initialize()
@@ -151,14 +152,8 @@
 /obj/item/kinetic_crusher/ui_action_click(mob/user, actiontype)
 	set_light_on(!light_on)
 	playsound(user, 'sound/weapons/empty.ogg', 100, TRUE)
-	update_brightness(user)
 	update_icon()
 
-/obj/item/kinetic_crusher/proc/update_brightness(mob/user = null)
-	if(light_on)
-		set_light(brightness_on)
-	else
-		set_light(0)
 
 /obj/item/kinetic_crusher/update_icon_state()
 	inhand_icon_state = "crusher[wielded]" // this is not icon_state and not supported by 2hcomponent

code/modules/mining/lavaland/necropolis_chests.dm

@@ -287,7 +287,9 @@
 	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

@@ -35,6 +35,8 @@
 	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/obj/item/gun/energy/kinetic_accelerator/minebot/stored_gun
@@ -59,6 +61,7 @@
 
 	SetCollectBehavior()
 
+
 /mob/living/simple_animal/hostile/mining_drone/Destroy()
 	for (var/datum/action/innate/minedrone/action in actions)
 		qdel(action)
@@ -234,16 +237,13 @@
 	name = "Toggle Light"
 	button_icon_state = "mech_lights_off"
 
+
 /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 class='notice'>You toggle your light [user.light_on ? "on" : "off"].</span>")
 
+
 /datum/action/innate/minedrone/toggle_mode
 	name = "Toggle Mode"
 	button_icon_state = "mech_cycle_equip_off"

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/datum/hud/living/carbon/hud = null // hud
 	var/bootime = 0
@@ -144,6 +148,7 @@ GLOBAL_VAR_INIT(observer_default_invisibility, INVISIBILITY_OBSERVER)
 	show_data_huds()
 	data_huds_on = 1
 
+
 /mob/dead/observer/get_photo_description(obj/item/camera/camera)
 	if(!invisibility || camera.see_ghosts)
 		return "You can also see a g-g-g-g-ghooooost!"
@@ -901,12 +906,11 @@ This is the proc mobs get to turn into a ghost. Forked from ghostize due to comp
 	. = list("<span class='notice'><i>You examine [src] closer, and note the following...</i></span>")
 	. += list("\t><span class='admin'>[ADMIN_FULLMONTY(src)]</span>")
 
+
 /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

@@ -39,24 +39,36 @@
 	var/static/b2 = 149
 	//this is shit but how do i fix it? no clue.
 	var/drain_time = 0 //used to keep ethereals from spam draining power sources
+	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)
-		RegisterSignal(C, COMSIG_ATOM_EMAG_ACT, .proc/on_emag_act)
-		RegisterSignal(C, COMSIG_ATOM_EMP_ACT, .proc/on_emp_act)
+	. = ..()
+	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)
 	UnregisterSignal(C, COMSIG_ATOM_EMAG_ACT)
 	UnregisterSignal(C, COMSIG_ATOM_EMP_ACT)
+	QDEL_NULL(ethereal_light)
+	return ..()
+
 
 /datum/species/ethereal/random_name(gender,unique,lastname)
 	if(unique)
@@ -66,16 +78,18 @@
 
 	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 + (2 * healthpercent), 1 + (1 * 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

@@ -449,7 +449,9 @@
 	name = "luminescent glow"
 	desc = "Tell a coder if you're seeing this."
 	icon_state = "nothing"
+	light_system = MOVABLE_LIGHT
 	light_range = LUMINESCENT_DEFAULT_GLOW
+	light_power = 2.5
 	light_color = COLOR_WHITE
 
 /obj/effect/dummy/luminescent_glow/Initialize()
@@ -457,6 +459,7 @@
 	if(!isliving(loc))
 		return INITIALIZE_HINT_QDEL
 
+
 /datum/action/innate/integrate_extract
 	name = "Integrate Extract"
 	desc = "Eat a slime extract to use its properties."

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

@@ -238,8 +238,8 @@
 	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()
 		A.visible_message("<span class='danger'>The light in [PDA] shorts out!</span>")
 	else

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

@@ -13,6 +13,8 @@
 	radio = /obj/item/radio/borg
 
 	blocks_emissive = EMISSIVE_BLOCK_UNIQUE
+	light_system = MOVABLE_LIGHT
+	light_on = FALSE
 
 	var/custom_name = ""
 	var/braintype = "Cyborg"
@@ -105,7 +107,6 @@
 
 	wires = new /datum/wires/robot(src)
 	AddComponent(/datum/component/empprotection, EMP_PROTECT_WIRES)
-
 	RegisterSignal(src, COMSIG_PROCESS_BORGCHARGER_OCCUPANT, .proc/charge)
 
 	robot_modules_background = new()
@@ -537,31 +538,39 @@
 		return //won't work if dead
 	set_autosay()
 
+
 /mob/living/silicon/robot/proc/control_headlamp()
 	if(stat || lamp_cooldown > world.time || low_power_mode)
 		to_chat(src, "<span class='danger'>This function is currently offline.</span>")
 		return
 
-//Some sort of magical "modulo" thing which somehow increments lamp power by 2, until it hits the max and resets to 0.
-	lamp_intensity = (lamp_intensity+2) % (lamp_max+2)
-	to_chat(src, "<span class='notice'>[lamp_intensity ? "Headlamp power set to Level [lamp_intensity/2]" : "Headlamp disabled"].</span>")
+	if(lamp_intensity == 0) //We'll skip intensity of 2, since every mob already has such a see-darkness range, so no much need for it.
+		lamp_intensity = 4
+	else //Some sort of magical "modulo" thing which somehow increments lamp power by 2, until it hits the max and resets to 0.
+		lamp_intensity = (lamp_intensity + 2) % (lamp_max + 2)
+	to_chat(src, "<span class='notice'>[lamp_intensity > 2 ? "Headlamp power set to Level [lamp_intensity * 0.5]" : "Headlamp disabled"].</span>")
 	update_headlamp()
 
-/mob/living/silicon/robot/proc/update_headlamp(turn_off = 0, cooldown = 100)
-	set_light(0)
 
-	if(lamp_intensity && (turn_off || stat || low_power_mode))
-		to_chat(src, "<span class='danger'>Your headlamp has been deactivated.</span>")
-		lamp_intensity = 0
-		lamp_cooldown = cooldown == BORG_LAMP_CD_RESET ? 0 : max(world.time + cooldown, lamp_cooldown)
+/mob/living/silicon/robot/proc/update_headlamp(turn_off = FALSE, cooldown = 10 SECONDS)
+	if(lamp_intensity > 2)
+		if(turn_off || stat || low_power_mode)
+			to_chat(src, "<span class='danger'>Your headlamp has been deactivated.</span>")
+			lamp_intensity = 0
+			lamp_cooldown = cooldown == BORG_LAMP_CD_RESET ? 0 : max(world.time + cooldown, lamp_cooldown)
+			set_light_on(FALSE)
+		else
+			set_light_range(lamp_intensity * 0.5)
+			set_light_on(TRUE)
 	else
-		set_light(lamp_intensity)
+		set_light_on(FALSE)
 
 	if(lamp_button)
 		lamp_button.icon_state = "lamp[lamp_intensity]"
 
 	update_icons()
 
+
 /mob/living/silicon/robot/proc/deconstruct()
 	SEND_SIGNAL(src, COMSIG_BORG_SAFE_DECONSTRUCT)
 	var/turf/T = get_turf(src)

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

@@ -4,7 +4,6 @@
 	layer = MOB_LAYER
 	gender = NEUTER
 	mob_biotypes = MOB_ROBOTIC
-	light_range = 3
 	stop_automated_movement = 1
 	wander = 0
 	healable = 0
@@ -23,6 +22,9 @@
 	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 +130,7 @@
 		return FALSE
 	on = TRUE
 	update_mobility()
-	set_light(initial(light_range))
+	set_light_on(on)
 	update_icon()
 	to_chat(src, "<span class='boldnotice'>You turned on!</span>")
 	diag_hud_set_botstat()
@@ -137,7 +139,7 @@
 /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.
 	to_chat(src, "<span class='userdanger'>You turned off!</span>")
 	update_icon()

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

@@ -17,11 +17,11 @@
 	window_name = "Discomatic Vibe Bot v1.05"
 	data_hud_type = DATA_HUD_DIAGNOSTIC_BASIC // show jobs
 	path_image_color = "#2cac12"
-
-	var/current_color
-	var/range = 7
-	var/power = 3
 	auto_patrol = TRUE
+	light_system = MOVABLE_LIGHT
+	light_range = 7
+	light_power = 3
+
 
 /mob/living/simple_animal/bot/vibebot/Initialize()
 	. = ..()
@@ -48,9 +48,8 @@
 
 /mob/living/simple_animal/bot/vibebot/proc/Vibe()
 	remove_atom_colour(TEMPORARY_COLOUR_PRIORITY)
-	current_color = random_color()
-	set_light(range, power, current_color)
-	add_atom_colour("#[current_color]", TEMPORARY_COLOUR_PRIORITY)
+	add_atom_colour("#[random_color()]", TEMPORARY_COLOUR_PRIORITY)
+	set_light_color(color)
 	update_icon()
 
 /mob/living/simple_animal/bot/vibebot/proc/retaliate(mob/living/carbon/human/H)

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

@@ -42,6 +42,9 @@ 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/mutable_appearance/cooloverlay
@@ -370,13 +373,15 @@ GLOBAL_LIST_EMPTY(parasites) //all currently existing/living guardians
 /mob/living/simple_animal/hostile/guardian/proc/ToggleMode()
 	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 class='notice'>You activate your light.</span>")
-		set_light(3)
+		set_light_on(TRUE)
 	else
 		to_chat(src, "<span class='notice'>You deactivate your light.</span>")
-		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

@@ -60,10 +60,10 @@
 	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)
-		
+
 /mob/living/simple_animal/hostile/hivebot/death(gibbed)
 	do_sparks(3, TRUE, src)
 	..(TRUE)
@@ -96,7 +96,7 @@
 	health = 80
 	maxHealth = 80
 	ranged = TRUE
-	
+
 /mob/living/simple_animal/hostile/hivebot/mechanic
 	name = "hivebot mechanic"
 	icon_state = "strong"
@@ -109,12 +109,12 @@
 	rapid = 3
 	gold_core_spawnable = HOSTILE_SPAWN
 	var/datum/action/innate/hivebot/foamwall/foam
-	
+
 /mob/living/simple_animal/hostile/hivebot/mechanic/Initialize()
 	. = ..()
 	foam = new
 	foam.Grant(src)
-	
+
 /mob/living/simple_animal/hostile/hivebot/mechanic/AttackingTarget()
 	if(istype(target, /obj/machinery))
 		var/obj/machinery/fixable = target
@@ -139,14 +139,14 @@
 			to_chat(src, "<span class='warning'>Repairs complete.</span>")
 		return
 	return ..()
-	
+
 /datum/action/innate/hivebot
 	background_icon_state = "bg_default"
-	
+
 /datum/action/innate/hivebot/foamwall
 	name = "Foam Wall"
 	desc = "Creates a foam wall that resists against the vacuum of space."
-	
+
 /datum/action/innate/hivebot/foamwall/Activate()
 	var/mob/living/simple_animal/hostile/hivebot/H = owner
 	var/turf/T = get_turf(H)

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

@@ -232,6 +232,7 @@ 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/mining_mobs/basilisk.dm

@@ -160,6 +160,7 @@
 	icon_dead = "watcher_magmawing_dead"
 	maxHealth = 215 //Compensate for the lack of slowdown on projectiles with a bit of extra health
 	health = 215
+	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_hairstyle
 	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/photography/camera/camera.dm

@@ -10,8 +10,11 @@
 	worn_icon_state = "camera"
 	lefthand_file = 'icons/mob/inhands/misc/devices_lefthand.dmi'
 	righthand_file = 'icons/mob/inhands/misc/devices_righthand.dmi'
+	light_system = MOVABLE_LIGHT //Used as a flash here.
+	light_range = 8
 	light_color = COLOR_WHITE
 	light_power = FLASH_LIGHT_POWER
+	light_on = FALSE
 	w_class = WEIGHT_CLASS_SMALL
 	flags_1 = CONDUCT_1
 	slot_flags = ITEM_SLOT_NECK
@@ -38,6 +41,7 @@
 	var/can_customise = TRUE
 	var/default_picture_name
 
+
 /obj/item/camera/attack_self(mob/user)
 	if(!disk)
 		return
@@ -160,7 +164,8 @@
 
 /obj/item/camera/proc/captureimage(atom/target, mob/user, flag, size_x = 1, size_y = 1)
 	if(flash_enabled)
-		flash_lighting_fx(8, light_power, light_color)
+		set_light_on(TRUE)
+		addtimer(CALLBACK(src, .proc/flash_end), FLASH_LIGHT_DURATION, TIMER_OVERRIDE|TIMER_UNIQUE)
 	blending = TRUE
 	var/turf/target_turf = get_turf(target)
 	if(!isturf(target_turf))
@@ -211,6 +216,11 @@
 	after_picture(user, P, flag)
 	blending = FALSE
 
+
+/obj/item/camera/proc/flash_end()
+	set_light_on(FALSE)
+
+
 /obj/item/camera/proc/after_picture(mob/user, datum/picture/picture, proximity_flag)
 	printpicture(user, picture)
 

code/modules/projectiles/gun.dm

@@ -398,9 +398,7 @@
 			if(!user.transferItemToLoc(I, src))
 				return
 			to_chat(user, "<span class='notice'>You click [S] into place on [src].</span>")
-			if(S.on)
-				set_light(0)
-			gun_light = S
+			set_gun_light(S)
 			update_gunlight()
 			alight = new(src)
 			if(loc == user)
@@ -508,12 +506,30 @@
 	if(!gun_light)
 		return
 	var/obj/item/flashlight/seclite/removed_light = gun_light
-	gun_light = null
+	set_gun_light(null)
 	update_gunlight()
 	removed_light.update_brightness()
 	QDEL_NULL(alight)
 	return TRUE
 
+
+///Called when gun_light value changes.
+/obj/item/gun/proc/set_gun_light(obj/item/flashlight/seclite/new_light)
+	if(gun_light == new_light)
+		return
+	. = gun_light
+	gun_light = new_light
+	if(gun_light)
+		gun_light.set_light_flags(gun_light.light_flags | LIGHT_ATTACHED)
+		if(gun_light.loc != src)
+			gun_light.forceMove(src)
+	else if(.)
+		var/obj/item/flashlight/seclite/old_gun_light = .
+		old_gun_light.set_light_flags(old_gun_light.light_flags & ~LIGHT_ATTACHED)
+		if(old_gun_light.loc == src)
+			old_gun_light.forceMove(get_turf(src))
+
+
 /obj/item/gun/ui_action_click(mob/user, actiontype)
 	if(istype(actiontype, alight))
 		toggle_gunlight()
@@ -526,19 +542,13 @@
 
 	var/mob/living/carbon/human/user = usr
 	gun_light.on = !gun_light.on
+	gun_light.update_brightness()
 	to_chat(user, "<span class='notice'>You toggle the gunlight [gun_light.on ? "on":"off"].</span>")
 
 	playsound(user, 'sound/weapons/empty.ogg', 100, TRUE)
 	update_gunlight()
 
 /obj/item/gun/proc/update_gunlight()
-	if(gun_light)
-		if(gun_light.on)
-			set_light(gun_light.brightness_on)
-		else
-			set_light(0)
-	else
-		set_light(0)
 	update_icon()
 	for(var/X in actions)
 		var/datum/action/A = X

code/modules/projectiles/guns/energy/energy_gun.dm

@@ -26,7 +26,7 @@
 	flight_y_offset = 13
 
 /obj/item/gun/energy/e_gun/mini/Initialize()
-	gun_light = new /obj/item/flashlight/seclite(src)
+	set_gun_light(new /obj/item/flashlight/seclite(src))
 	return ..()
 
 /obj/item/gun/energy/e_gun/stun

code/modules/projectiles/projectile/beams.dm

@@ -3,13 +3,15 @@
 	icon_state = "laser"
 	pass_flags = PASSTABLE | PASSGLASS | PASSGRILLE
 	damage = 20
-	light_range = 2
 	damage_type = BURN
 	hitsound = 'sound/weapons/sear.ogg'
 	hitsound_wall = 'sound/weapons/effects/searwall.ogg'
 	flag = "laser"
 	eyeblur = 2
 	impact_effect_type = /obj/effect/temp_visual/impact_effect/red_laser
+	light_system = MOVABLE_LIGHT
+	light_range = 2
+	light_power = 1
 	light_color = COLOR_SOFT_RED
 	ricochets_max = 50	//Honk!
 	ricochet_chance = 80
@@ -17,6 +19,7 @@
 	wound_bonus = -20
 	bare_wound_bonus = 10
 
+
 /obj/projectile/beam/laser
 	tracer_type = /obj/effect/projectile/tracer/laser
 	muzzle_type = /obj/effect/projectile/muzzle/laser

code/modules/reagents/chemistry/reagents/food_reagents.dm

@@ -679,17 +679,37 @@
 		. = TRUE
 	..()
 
+
 /datum/reagent/consumable/tinlux
 	name = "Tinea Luxor"
 	description = "A stimulating ichor which causes luminescent fungi to grow on the skin. "
 	color = "#b5a213"
 	taste_description = "tingling mushroom"
+	//Lazy list of mobs affected by the luminosity of this reagent.
+	var/list/mobs_affected
 
 /datum/reagent/consumable/tinlux/expose_mob(mob/living/M)
-	M.set_light(2)
+	add_reagent_light(M)
 
 /datum/reagent/consumable/tinlux/on_mob_end_metabolize(mob/living/M)
-	M.set_light(-2)
+	remove_reagent_light(M)
+
+/datum/reagent/consumable/tinlux/proc/on_living_holder_deletion(mob/living/source)
+	SIGNAL_HANDLER
+	remove_reagent_light(source)
+
+/datum/reagent/consumable/tinlux/proc/add_reagent_light(mob/living/living_holder)
+	var/obj/effect/dummy/lighting_obj/moblight/mob_light_obj = living_holder.mob_light(2)
+	LAZYSET(mobs_affected, living_holder, mob_light_obj)
+	RegisterSignal(living_holder, COMSIG_PARENT_QDELETING, .proc/on_living_holder_deletion)
+
+/datum/reagent/consumable/tinlux/proc/remove_reagent_light(mob/living/living_holder)
+	UnregisterSignal(living_holder, COMSIG_PARENT_QDELETING)
+	var/obj/effect/dummy/lighting_obj/moblight/mob_light_obj = LAZYACCESS(mobs_affected, living_holder)
+	LAZYREMOVE(mobs_affected, living_holder)
+	if(mob_light_obj)
+		qdel(mob_light_obj)
+
 
 /datum/reagent/consumable/vitfro
 	name = "Vitrium Froth"

code/modules/reagents/chemistry/recipes/pyrotechnics.dm

@@ -293,7 +293,7 @@
 	var/range = created_volume/3
 	if(isatom(holder.my_atom))
 		var/atom/A = holder.my_atom
-		A.flash_lighting_fx(_range = (range + 2), _reset_lighting = FALSE)
+		A.flash_lighting_fx(_range = (range + 2))
 	for(var/mob/living/C in get_hearers_in_view(range, location))
 		if(C.flash_act(affect_silicon = TRUE))
 			if(get_dist(C, location) < 4)
@@ -312,7 +312,7 @@
 	var/range = created_volume/10
 	if(isatom(holder.my_atom))
 		var/atom/A = holder.my_atom
-		A.flash_lighting_fx(_range = (range + 2), _reset_lighting = FALSE)
+		A.flash_lighting_fx(_range = (range + 2))
 	for(var/mob/living/C in get_hearers_in_view(range, location))
 		if(C.flash_act(affect_silicon = TRUE))
 			if(get_dist(C, location) < 4)

code/modules/spells/spell_types/lichdom.dm

@@ -81,8 +81,9 @@
 	icon = 'icons/obj/projectiles.dmi'
 	icon_state = "bluespace"
 	color = COLOR_VERY_DARK_LIME_GREEN
+	light_system = MOVABLE_LIGHT
+	light_range = 3
 	light_color = COLOR_VERY_DARK_LIME_GREEN
-	var/lon_range = 3
 	var/resurrections = 0
 	var/datum/mind/mind
 	var/respawn_time = 1800
@@ -97,7 +98,6 @@
 	active_phylacteries++
 	GLOB.poi_list |= src
 	START_PROCESSING(SSobj, src)
-	set_light(lon_range)
 	if(initial(SSticker.mode.round_ends_with_antag_death))
 		SSticker.mode.round_ends_with_antag_death = FALSE
 

code/modules/surgery/organs/eyes.dm

@@ -208,7 +208,7 @@
 	var/active = FALSE
 	var/max_light_beam_distance = 5
 	var/light_beam_distance = 5
-	var/light_object_range = 1
+	var/light_object_range = 2
 	var/light_object_power = 2
 	var/list/obj/effect/abstract/eye_lighting/eye_lighting
 	var/obj/effect/abstract/eye_lighting/on_mob
@@ -319,6 +319,7 @@
 		clear_visuals()
 	var/turf/scanning = scanfrom
 	var/stop = FALSE
+	on_mob.set_light_flags(on_mob.light_flags & ~LIGHT_ATTACHED)
 	on_mob.forceMove(scanning)
 	for(var/i in 1 to light_beam_distance)
 		scanning = get_step(scanning, scandir)
@@ -339,6 +340,7 @@
 			var/obj/effect/abstract/eye_lighting/L = i
 			L.forceMove(src)
 		if(!QDELETED(on_mob))
+			on_mob.set_light_flags(on_mob.light_flags | LIGHT_ATTACHED)
 			on_mob.forceMove(src)
 
 /obj/item/organ/eyes/robotic/glow/proc/start_visuals()
@@ -355,26 +357,39 @@
 
 /obj/item/organ/eyes/robotic/glow/proc/regenerate_light_effects()
 	clear_visuals(TRUE)
-	on_mob = new(src)
+	on_mob = new (src, light_object_range, light_object_power, current_color_string, LIGHT_ATTACHED)
 	for(var/i in 1 to light_beam_distance)
-		LAZYADD(eye_lighting,new /obj/effect/abstract/eye_lighting(src))
+		LAZYADD(eye_lighting, new /obj/effect/abstract/eye_lighting(src, light_object_range, light_object_power, current_color_string))
 	sync_light_effects()
 
+
 /obj/item/organ/eyes/robotic/glow/proc/sync_light_effects()
-	for(var/I in eye_lighting)
-		var/obj/effect/abstract/eye_lighting/L = I
-		L.set_light(light_object_range, light_object_power, current_color_string)
-	if(on_mob)
-		on_mob.set_light(1, 1, current_color_string)
+	for(var/e in eye_lighting)
+		var/obj/effect/abstract/eye_lighting/eye_lighting = e
+		eye_lighting.set_light_color(current_color_string)
+	on_mob?.set_light_color(current_color_string)
+
 
 /obj/effect/abstract/eye_lighting
+	light_system = MOVABLE_LIGHT
 	var/obj/item/organ/eyes/robotic/glow/parent
 
-/obj/effect/abstract/eye_lighting/Initialize()
+
+/obj/effect/abstract/eye_lighting/Initialize(mapload, light_object_range, light_object_power, current_color_string, light_flags)
 	. = ..()
 	parent = loc
 	if(!istype(parent))
+		stack_trace("/obj/effect/abstract/eye_lighting added to improper parent ([loc]). Deleting.")
 		return INITIALIZE_HINT_QDEL
+	if(!isnull(light_object_range))
+		set_light_range(light_object_range)
+	if(!isnull(light_object_power))
+		set_light_power(light_object_power)
+	if(!isnull(current_color_string))
+		set_light_color(current_color_string)
+	if(!isnull(light_flags))
+		set_light_flags(light_flags)
+
 
 /obj/item/organ/eyes/moth
 	name = "moth eyes"

code/modules/surgery/tools.dm

@@ -265,25 +265,24 @@
 	hitsound = 'sound/weapons/blade1.ogg'
 	force = 16
 	toolspeed = 0.7
+	light_system = MOVABLE_LIGHT
+	light_range = 1
 	light_color = LIGHT_COLOR_GREEN
 	sharpness = SHARP_EDGED
 
-/obj/item/scalpel/advanced/Initialize()
-	. = ..()
-	set_light(1)
 
 /obj/item/scalpel/advanced/attack_self(mob/user)
 	playsound(get_turf(user), 'sound/machines/click.ogg', 50, TRUE)
 	if(tool_behaviour == TOOL_SCALPEL)
 		tool_behaviour = TOOL_SAW
 		to_chat(user, "<span class='notice'>You increase the power of [src], now it can cut bones.</span>")
-		set_light(2)
+		set_light_range(2)
 		force += 1 //we don't want to ruin sharpened stuff
 		icon_state = "saw_a"
 	else
 		tool_behaviour = TOOL_SCALPEL
 		to_chat(user, "<span class='notice'>You lower the power of [src], it can no longer cut bones.</span>")
-		set_light(1)
+		set_light_range(1)
 		force -= 1
 		icon_state = "scalpel_a"
 
@@ -320,11 +319,10 @@
 	icon_state = "surgicaldrill_a"
 	hitsound = 'sound/items/welder.ogg'
 	toolspeed = 0.7
+	light_system = MOVABLE_LIGHT
+	light_range = 1
 	light_color = COLOR_SOFT_RED
 
-/obj/item/surgicaldrill/advanced/Initialize()
-	. = ..()
-	set_light(1)
 
 /obj/item/surgicaldrill/advanced/attack_self(mob/user)
 	playsound(get_turf(user), 'sound/weapons/tap.ogg', 50, TRUE)

code/modules/swarmers/swarmer.dm

@@ -60,6 +60,8 @@
 	loot = list(/obj/effect/decal/cleanable/robot_debris, /obj/item/stack/ore/bluespace_crystal)
 	del_on_death = 1
 	deathmessage = "explodes with a sharp pop!"
+	light_system = MOVABLE_LIGHT
+	light_range = 3
 	light_color = LIGHT_COLOR_CYAN
 	hud_type = /datum/hud/swarmer
 	speech_span = SPAN_ROBOT
@@ -69,6 +71,9 @@
 	var/max_resources = 100
 	///List used for player swarmers to keep track of their drones
 	var/list/mob/living/simple_animal/hostile/swarmer/melee/dronelist
+	///Bitflags to store boolean conditions, such as whether the light is on or off.
+	var/swarmer_flags = NONE
+
 
 /mob/living/simple_animal/hostile/swarmer/Initialize()
 	. = ..()
@@ -76,6 +81,7 @@
 	for(var/datum/atom_hud/data/diagnostic/diag_hud in GLOB.huds)
 		diag_hud.add_to_hud(src)
 
+
 /mob/living/simple_animal/hostile/swarmer/med_hud_set_health()
 	var/image/holder = hud_list[DIAG_HUD]
 	var/icon/I = icon(icon, icon_state, dir)
@@ -374,20 +380,25 @@
   * Proc used to allow a swarmer to toggle its  light on and off.  If a swarmer has any drones, change their light settings to match their master's.
   */
 /mob/living/simple_animal/hostile/swarmer/proc/toggle_light()
-	if(!light_range)
-		set_light(3)
+	if(swarmer_flags & SWARMER_LIGHT_ON)
+		swarmer_flags = ~SWARMER_LIGHT_ON
+		set_light_on(FALSE)
 		if(!mind)
 			return
 		for(var/d in dronelist)
 			var/mob/living/simple_animal/hostile/swarmer/melee/drone = d
-			drone.set_light(3)
-	else
-		set_light(0)
-		if(!mind)
-			return
-		for(var/d in dronelist)
-			var/mob/living/simple_animal/hostile/swarmer/melee/drone = d
-			drone.set_light(0)
+			drone.swarmer_flags = ~SWARMER_LIGHT_ON
+			drone.set_light_on(FALSE)
+		return
+	swarmer_flags |= SWARMER_LIGHT_ON
+	set_light_on(TRUE)
+	if(!mind)
+		return
+	for(var/d in dronelist)
+		var/mob/living/simple_animal/hostile/swarmer/melee/drone = d
+		drone.swarmer_flags |= SWARMER_LIGHT_ON
+		drone.set_light_on(TRUE)
+
 
 /**
   * Proc which is used for swarmer comms

tgstation.dme

@@ -440,6 +440,7 @@
 #include "code\datums\components\ntnet_interface.dm"
 #include "code\datums\components\omen.dm"
 #include "code\datums\components\orbiter.dm"
+#include "code\datums\components\overlay_lighting.dm"
 #include "code\datums\components\paintable.dm"
 #include "code\datums\components\payment.dm"
 #include "code\datums\components\pellet_cloud.dm"
@@ -682,6 +683,7 @@
 #include "code\game\atoms_movable.dm"
 #include "code\game\communications.dm"
 #include "code\game\data_huds.dm"
+#include "code\game\movable_luminosity.dm"
 #include "code\game\say.dm"
 #include "code\game\shuttle_engines.dm"
 #include "code\game\sound.dm"

tools/CreditsTool/obj/Debug/.NETFramework,Version=v4.6.1.AssemblyAttributes.cs

@@ -0,0 +1,4 @@
+// <autogenerated />
+using System;
+using System.Reflection;
+[assembly: global::System.Runtime.Versioning.TargetFrameworkAttribute(".NETFramework,Version=v4.6.1", FrameworkDisplayName = ".NET Framework 4.6.1")]