From 68621359136cb79947d8b5a82d10415b2b1cc0ba Mon Sep 17 00:00:00 2001
From: kyunkyunkyun <120701975+kyunkyunkyun@users.noreply.github.com>
Date: Tue, 9 Sep 2025 00:25:37 +0500
Subject: [PATCH] Ports some old TG lighting + opacity refactors (#29724)

* lighting ports

* missed these

* fix

* tweak optical scanners

* Update code/datums/elements/light_blocking.dm

Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>
Signed-off-by: kyunkyunkyun <120701975+kyunkyunkyun@users.noreply.github.com>

---------

Signed-off-by: Burzah <116982774+Burzah@users.noreply.github.com>
Signed-off-by: kyunkyunkyun <120701975+kyunkyunkyun@users.noreply.github.com>
Co-authored-by: Burzah <116982774+Burzah@users.noreply.github.com>
Co-authored-by: Contrabang <91113370+Contrabang@users.noreply.github.com>
---
 code/__DEFINES/dcs/atom_signals.dm            |   2 +
 code/__DEFINES/flags.dm                       |   3 +
 code/__DEFINES/turfs.dm                       |   2 +
 code/__HELPERS/game.dm                        |   4 +-
 code/__HELPERS/radiation_helpers.dm           |   3 -
 code/__HELPERS/unsorted.dm                    |  12 +-
 code/controllers/subsystem/SSlighting.dm      |   5 +-
 code/datums/elements/light_blocking.dm        |  32 +++
 code/datums/spells/mimic.dm                   |   1 -
 code/game/atoms.dm                            |   4 -
 code/game/atoms_movable.dm                    |  10 +-
 code/game/machinery/doors/airlock.dm          |   4 +-
 code/game/machinery/doors/airlock_types.dm    |   4 +-
 code/game/machinery/doors/door.dm             |   4 +-
 code/game/machinery/shieldgen.dm              |   3 -
 code/game/mecha/mecha.dm                      |   1 -
 code/game/mecha/working/ripley.dm             |   1 -
 code/game/objects/structures/aliens.dm        |   3 +-
 code/game/objects/structures/curtains.dm      |   2 +-
 code/game/objects/structures/flora.dm         |   4 +-
 code/game/objects/structures/mineral_doors.dm |   2 +-
 code/game/turfs/simulated/walls_mineral.dm    |  55 ++----
 code/game/turfs/space/space_turf.dm           |   2 +-
 code/game/turfs/turf.dm                       |  68 +++----
 code/modules/clothing/glasses/glasses.dm      |   2 +-
 code/modules/clothing/head/helmet.dm          |   2 +-
 code/modules/events/spacevine.dm              |   6 +-
 code/modules/lighting/lighting_atom.dm        |  33 ++--
 code/modules/lighting/lighting_corner.dm      | 162 +++++++++------
 code/modules/lighting/lighting_object.dm      | 168 ++++++----------
 code/modules/lighting/lighting_setup.dm       |   2 +-
 code/modules/lighting/lighting_source.dm      | 187 ++++++++----------
 code/modules/lighting/lighting_turf.dm        | 129 ++++++------
 .../living/simple_animal/hostile/hostile.dm   |   2 +-
 .../living/simple_animal/hostile/mushroom.dm  |   2 +-
 code/modules/paperwork/photography.dm         |  23 +--
 code/modules/power/generators/turbine.dm      |   2 -
 code/modules/shuttle/on_move.dm               |   4 -
 code/modules/shuttle/shuttle.dm               |   6 -
 icons/effects/lighting_object.dmi             | Bin 1256 -> 2092 bytes
 paradise.dme                                  |   1 +
 41 files changed, 456 insertions(+), 506 deletions(-)
 create mode 100644 code/datums/elements/light_blocking.dm

diff --git a/code/__DEFINES/dcs/atom_signals.dm b/code/__DEFINES/dcs/atom_signals.dm
index 54934917ece..e388110c76a 100644
--- a/code/__DEFINES/dcs/atom_signals.dm
+++ b/code/__DEFINES/dcs/atom_signals.dm
@@ -69,6 +69,8 @@
 #define COMSIG_ATOM_SING_PULL "atom_sing_pull"
 ///from base of atom/set_light(): (l_range, l_power, l_color)
 #define COMSIG_ATOM_SET_LIGHT "atom_set_light"
+/// from base of atom/set_opacity(): (new_opacity)
+#define COMSIG_ATOM_SET_OPACITY "atom_set_opacity"
 ///from base of atom/setDir(): (old_dir, new_dir)
 #define COMSIG_ATOM_DIR_CHANGE "atom_dir_change"
 ///from [/datum/controller/subsystem/processing/dcs/proc/rotate_decals]: (list/datum/element/decal/rotating)
diff --git a/code/__DEFINES/flags.dm b/code/__DEFINES/flags.dm
index 60c0c6fda0f..f26be195ad8 100644
--- a/code/__DEFINES/flags.dm
+++ b/code/__DEFINES/flags.dm
@@ -1,6 +1,9 @@
 #define ALL ~0 //For convenience.
 #define NONE 0
 
+/// All the cardinal direction bitflags.
+#define ALL_CARDINALS (NORTH | SOUTH | EAST | WEST)
+
 //FLAGS BITMASK
 #define STOPSPRESSUREDMAGE		(1<<0)		//This flag is used on the flags variable for SUIT and HEAD items which stop pressure damage. Note that the flag 1 was previous used as ONBACK, so it is possible for some code to use (flags & 1) when checking if something can be put on your back. Replace this code with (inv_flags & ITEM_SLOT_BACK) if you see it anywhere To successfully stop you taking all pressure damage you must have both a suit and head item with this flag.
 #define NODROP					(1<<1)		// This flag makes it so that an item literally cannot be removed at all, or at least that's how it should be. Only deleted.
diff --git a/code/__DEFINES/turfs.dm b/code/__DEFINES/turfs.dm
index f3149bb42aa..a6f4353a714 100644
--- a/code/__DEFINES/turfs.dm
+++ b/code/__DEFINES/turfs.dm
@@ -20,3 +20,5 @@
 	CORNER_BLOCK_OFFSET(corner, width + 2, 1, -1, height) + \
 	CORNER_BLOCK_OFFSET(corner, 1, height, -1, 0) + \
 	CORNER_BLOCK_OFFSET(corner, 1, height, width, 0))
+
+#define IS_OPAQUE_TURF(turf) (turf.directional_opacity == ALL_CARDINALS)
diff --git a/code/__HELPERS/game.dm b/code/__HELPERS/game.dm
index fbb60db265a..1b9be7b3c5b 100644
--- a/code/__HELPERS/game.dm
+++ b/code/__HELPERS/game.dm
@@ -268,7 +268,7 @@
 			Y1+=s
 			while(Y1!=Y2)
 				T=locate(X1,Y1,Z)
-				if(T.opacity)
+				if(IS_OPAQUE_TURF(T))
 					return 0
 				Y1+=s
 	else
@@ -284,7 +284,7 @@
 			else
 				X1+=signX //Line exits tile horizontally
 			T=locate(X1,Y1,Z)
-			if(T.opacity)
+			if(IS_OPAQUE_TURF(T))
 				return 0
 	return 1
 
diff --git a/code/__HELPERS/radiation_helpers.dm b/code/__HELPERS/radiation_helpers.dm
index b5ee6832832..017d29a78cd 100644
--- a/code/__HELPERS/radiation_helpers.dm
+++ b/code/__HELPERS/radiation_helpers.dm
@@ -9,7 +9,6 @@
 		/mob/dead,
 		/obj/effect,
 		/obj/docking_port,
-		/atom/movable/lighting_object,
 		/obj/item/projectile,
 		/atom/movable/emissive_blocker,
 	))
@@ -55,7 +54,6 @@
 		/mob/dead,
 		/obj/effect,
 		/obj/docking_port,
-		/atom/movable/lighting_object,
 		/obj/item/projectile,
 		/atom/movable/emissive_blocker,
 	))
@@ -111,7 +109,6 @@
 		/mob/dead,
 		/obj/effect,
 		/obj/docking_port,
-		/atom/movable/lighting_object,
 		/obj/item/projectile,
 		/atom/movable/emissive_blocker,
 	))
diff --git a/code/__HELPERS/unsorted.dm b/code/__HELPERS/unsorted.dm
index 336ddc6e160..151fdc5a924 100644
--- a/code/__HELPERS/unsorted.dm
+++ b/code/__HELPERS/unsorted.dm
@@ -644,17 +644,13 @@ Returns 1 if the chain up to the area contains the given typepath
 		current = get_step_towards(current, target_turf)
 		while(current != target_turf)
 			if(steps > length)
-				return 0
-			if(current.opacity)
-				return 0
-			for(var/thing in current)
-				var/atom/A = thing
-				if(A.opacity)
-					return 0
+				return FALSE
+			if(IS_OPAQUE_TURF(current))
+				return FALSE
 			current = get_step_towards(current, target_turf)
 			steps++
 
-	return 1
+	return TRUE
 
 //Returns: all the areas in the world
 /proc/return_areas()
diff --git a/code/controllers/subsystem/SSlighting.dm b/code/controllers/subsystem/SSlighting.dm
index 1628f46b396..139c1e3701a 100644
--- a/code/controllers/subsystem/SSlighting.dm
+++ b/code/controllers/subsystem/SSlighting.dm
@@ -60,8 +60,9 @@ SUBSYSTEM_DEF(lighting)
 	for(i in 1 to length(queue))
 		var/datum/lighting_corner/C = queue[i]
 
-		C.update_objects()
 		C.needs_update = FALSE
+		C.update_objects()
+
 		if(init_tick_checks)
 			CHECK_TICK
 		else if(MC_TICK_CHECK)
@@ -76,7 +77,7 @@ SUBSYSTEM_DEF(lighting)
 
 	queue = objects_queue
 	for(i in 1 to length(queue))
-		var/atom/movable/lighting_object/O = queue[i]
+		var/datum/lighting_object/O = queue[i]
 
 		if(QDELETED(O))
 			continue
diff --git a/code/datums/elements/light_blocking.dm b/code/datums/elements/light_blocking.dm
new file mode 100644
index 00000000000..0746c37b757
--- /dev/null
+++ b/code/datums/elements/light_blocking.dm
@@ -0,0 +1,32 @@
+/**
+  * Attached to movable atoms with opacity. Listens to them move and updates their old and new turf loc's opacity accordingly
+  */
+/datum/element/light_blocking
+	element_flags = ELEMENT_DETACH_ON_HOST_DESTROY
+
+/datum/element/light_blocking/Attach(datum/target)
+	. = ..()
+	if(!ismovable(target))
+		return ELEMENT_INCOMPATIBLE
+	RegisterSignal(target, COMSIG_MOVABLE_MOVED, PROC_REF(on_target_move))
+	var/atom/movable/movable_target = target
+	if(isturf(movable_target.loc))
+		var/turf/turf_loc = movable_target.loc
+		turf_loc.add_opacity_source(target)
+
+/datum/element/light_blocking/Detach(atom/movable/target)
+	. = ..()
+	UnregisterSignal(target, COMSIG_MOVABLE_MOVED)
+	var/atom/movable/movable_target = target
+	if(isturf(movable_target.loc))
+		var/turf/turf_loc = movable_target.loc
+		turf_loc.remove_opacity_source(target)
+
+/// Updates old and new turf loc opacities
+/datum/element/light_blocking/proc/on_target_move(atom/movable/source, atom/old_loc, dir, forced = FALSE)
+	if(isturf(old_loc))
+		var/turf/old_turf = old_loc
+		old_turf.remove_opacity_source(source)
+	if(isturf(source.loc))
+		var/turf/new_turf = source.loc
+		new_turf.add_opacity_source(source)
diff --git a/code/datums/spells/mimic.dm b/code/datums/spells/mimic.dm
index 96b7f8081cc..05751a7ec20 100644
--- a/code/datums/spells/mimic.dm
+++ b/code/datums/spells/mimic.dm
@@ -22,7 +22,6 @@
 		/obj/singularity,
 		/obj/effect,
 		/mob/living/simple_animal/hostile/megafauna,
-		/atom/movable/lighting_object,
 		/obj/machinery/dna_vault,
 		/obj/machinery/power/bluespace_tap,
 		/obj/machinery/barsign,
diff --git a/code/game/atoms.dm b/code/game/atoms.dm
index 3bfcffd266c..d435c5bfc1e 100644
--- a/code/game/atoms.dm
+++ b/code/game/atoms.dm
@@ -190,10 +190,6 @@
 	if(light_power && light_range)
 		update_light()
 
-	if(opacity && isturf(loc))
-		var/turf/T = loc
-		T.has_opaque_atom = TRUE // No need to recalculate it in this case, it's guranteed to be on afterwards anyways.
-
 	if(loc)
 		SEND_SIGNAL(loc, COMSIG_ATOM_INITIALIZED_ON, src) // Used for poolcontroller / pool to improve performance greatly. However it also open up path to other usage of observer pattern on turfs.
 
diff --git a/code/game/atoms_movable.dm b/code/game/atoms_movable.dm
index 5890ac77d51..2f8fe74348d 100644
--- a/code/game/atoms_movable.dm
+++ b/code/game/atoms_movable.dm
@@ -102,6 +102,8 @@
 			render_target = ref(src)
 			em_block = new(src, render_target)
 			add_overlay(list(em_block))
+	if(opacity)
+		AddElement(/datum/element/light_blocking)
 
 /atom/movable/proc/update_emissive_block()
 	if(!em_block && !QDELETED(src))
@@ -110,7 +112,6 @@
 	add_overlay(list(em_block))
 
 /atom/movable/Destroy()
-	var/turf/T = loc
 	unbuckle_all_mobs(force = TRUE)
 	QDEL_NULL(em_block)
 
@@ -131,11 +132,8 @@
 			qdel(move_packet)
 		move_packet = null
 
-	if(opacity && istype(T))
-		var/old_has_opaque_atom = T.has_opaque_atom
-		T.recalc_atom_opacity()
-		if(old_has_opaque_atom != T.has_opaque_atom)
-			T.reconsider_lights()
+	if(opacity)
+		RemoveElement(/datum/element/light_blocking)
 
 //Returns an atom's power cell, if it has one. Overload for individual items.
 /atom/movable/proc/get_cell()
diff --git a/code/game/machinery/doors/airlock.dm b/code/game/machinery/doors/airlock.dm
index 3f7a56fb144..42509fd4730 100644
--- a/code/game/machinery/doors/airlock.dm
+++ b/code/game/machinery/doors/airlock.dm
@@ -1266,7 +1266,7 @@ GLOBAL_LIST_EMPTY(airlock_emissive_underlays)
 	recalculate_atmos_connectivity()
 	update_icon(AIRLOCK_OPENING, 1)
 	sleep(1)
-	set_opacity(0)
+	set_opacity(FALSE)
 	if(width > 1)
 		set_fillers_opacity(0)
 	update_freelook_sight()
@@ -1320,7 +1320,7 @@ GLOBAL_LIST_EMPTY(airlock_emissive_underlays)
 	if(!safe)
 		crush()
 	if((visible && !glass) || polarized_on)
-		set_opacity(1)
+		set_opacity(TRUE)
 		if(width > 1)
 			set_fillers_opacity(1)
 	update_freelook_sight()
diff --git a/code/game/machinery/doors/airlock_types.dm b/code/game/machinery/doors/airlock_types.dm
index 78e35cda0a2..3719fa35d8f 100644
--- a/code/game/machinery/doors/airlock_types.dm
+++ b/code/game/machinery/doors/airlock_types.dm
@@ -573,7 +573,7 @@
 /obj/machinery/door/airlock/cult/cult_conceal()
 	icon = stealth_icon
 	overlays_file = stealth_overlays
-	opacity = stealth_opacity
+	set_opacity(stealth_opacity)
 	glass = stealth_glass
 	airlock_material = stealth_airlock_material
 	name = "airlock"
@@ -584,7 +584,7 @@
 /obj/machinery/door/airlock/cult/cult_reveal()
 	icon = GET_CULT_DATA(airlock_runed_icon_file, initial(icon))
 	overlays_file = GET_CULT_DATA(airlock_runed_overlays_file, initial(overlays_file))
-	opacity = initial(opacity)
+	set_opacity(initial(opacity))
 	glass = initial(glass)
 	airlock_material = initial(airlock_material)
 	name = initial(name)
diff --git a/code/game/machinery/doors/door.dm b/code/game/machinery/doors/door.dm
index 1c8044b4c8d..1b991677215 100644
--- a/code/game/machinery/doors/door.dm
+++ b/code/game/machinery/doors/door.dm
@@ -385,7 +385,7 @@
 	operating = DOOR_OPENING
 	recalculate_atmos_connectivity()
 	do_animate("opening")
-	set_opacity(0)
+	set_opacity(FALSE)
 	if(width > 1)
 		set_fillers_opacity(0)
 	sleep(5)
@@ -395,7 +395,7 @@
 	sleep(5)
 	layer = initial(layer)
 	update_icon()
-	set_opacity(0)
+	set_opacity(FALSE)
 	if(width > 1)
 		set_fillers_opacity(0)
 	operating = NONE
diff --git a/code/game/machinery/shieldgen.dm b/code/game/machinery/shieldgen.dm
index 9a3558c9ad7..2ed5256816d 100644
--- a/code/game/machinery/shieldgen.dm
+++ b/code/game/machinery/shieldgen.dm
@@ -11,13 +11,10 @@
 
 /obj/machinery/shield/Initialize(mapload)
 	. = ..()
-	dir = pick(NORTH, SOUTH, EAST, WEST)
 	recalculate_atmos_connectivity()
 	GLOB.tesla_containment += src
 
 /obj/machinery/shield/Destroy()
-	opacity = FALSE
-	density = FALSE
 	recalculate_atmos_connectivity()
 	GLOB.tesla_containment -= src
 	return ..()
diff --git a/code/game/mecha/mecha.dm b/code/game/mecha/mecha.dm
index 2fe203246db..36324869f8a 100644
--- a/code/game/mecha/mecha.dm
+++ b/code/game/mecha/mecha.dm
@@ -6,7 +6,6 @@
 	icon = 'icons/mecha/mecha.dmi'
 
 	density = TRUE //Dense. To raise the heat.
-	opacity = TRUE ///opaque. Menacing.
 	anchored = TRUE //no pulling around.
 	resistance_flags = FIRE_PROOF
 	layer = MOB_LAYER //icon draw layer
diff --git a/code/game/mecha/working/ripley.dm b/code/game/mecha/working/ripley.dm
index 63c41f73dde..bd44b6c9a1f 100644
--- a/code/game/mecha/working/ripley.dm
+++ b/code/game/mecha/working/ripley.dm
@@ -169,7 +169,6 @@
 	initial_icon = "deathripley"
 	step_in = 3
 	slow_pressure_step_in = 3
-	opacity=0
 	max_temperature = 65000
 	max_integrity = 300
 	armor = list(MELEE = 40, BULLET = 40, LASER = 40, ENERGY = 0, BOMB = 70, RAD = 0, FIRE = 100, ACID = 100)
diff --git a/code/game/objects/structures/aliens.dm b/code/game/objects/structures/aliens.dm
index c07c42989d4..b479106a8b3 100644
--- a/code/game/objects/structures/aliens.dm
+++ b/code/game/objects/structures/aliens.dm
@@ -102,7 +102,6 @@
 */
 /obj/structure/alien/resin/door
 	name = "resin door"
-
 	icon = 'icons/obj/smooth_structures/alien/resin_door.dmi'
 	icon_state = "resin"
 	base_icon_state = "resin"
@@ -187,7 +186,7 @@
 		playsound(loc, close_sound, 50, 1)
 		flick("[initial_state]closing", src)
 	density = !density
-	opacity = !opacity
+	set_opacity(!opacity)
 	state_open = !state_open
 	addtimer(CALLBACK(src, PROC_REF(operate_update), bumped_open), 1 SECONDS)
 
diff --git a/code/game/objects/structures/curtains.dm b/code/game/objects/structures/curtains.dm
index ffedc3fed4b..8bfb3fc0126 100644
--- a/code/game/objects/structures/curtains.dm
+++ b/code/game/objects/structures/curtains.dm
@@ -135,7 +135,7 @@
 /obj/structure/curtain/update_overlays()
 	. = ..()
 	if(!assembled)
-		opacity = FALSE
+		set_opacity(FALSE)
 		return
 
 	if(opacity)
diff --git a/code/game/objects/structures/flora.dm b/code/game/objects/structures/flora.dm
index 6c34a2c0ad1..0c735c95982 100644
--- a/code/game/objects/structures/flora.dm
+++ b/code/game/objects/structures/flora.dm
@@ -433,7 +433,7 @@
 	. = ..()
 	if(icon_state == "random-alien")
 		icon_state = "alien-[rand(1,8)]"
-	
+
 /obj/item/kirbyplants/large/alien/alien1
 	icon_state = "alien-1"
 /obj/item/kirbyplants/large/alien/alien3
@@ -519,7 +519,7 @@
 /obj/structure/bush/Initialize(mapload)
 	. = ..()
 	if(prob(20))
-		opacity = TRUE
+		set_opacity(TRUE)
 
 /*
 /obj/structure/bush/Bumped(M as mob)
diff --git a/code/game/objects/structures/mineral_doors.dm b/code/game/objects/structures/mineral_doors.dm
index 5ae9bdab683..64602411892 100644
--- a/code/game/objects/structures/mineral_doors.dm
+++ b/code/game/objects/structures/mineral_doors.dm
@@ -101,7 +101,7 @@
 
 /obj/structure/mineral_door/proc/operate_update()
 	density = !density
-	opacity = !opacity
+	set_opacity(!opacity)
 	state_open = !state_open
 	recalculate_atmos_connectivity()
 	update_icon(UPDATE_ICON_STATE)
diff --git a/code/game/turfs/simulated/walls_mineral.dm b/code/game/turfs/simulated/walls_mineral.dm
index fde37f33e58..a4253b4efbf 100644
--- a/code/game/turfs/simulated/walls_mineral.dm
+++ b/code/game/turfs/simulated/walls_mineral.dm
@@ -214,6 +214,10 @@
 	smoothing_groups = list(SMOOTH_GROUP_TITANIUM_WALLS, SMOOTH_GROUP_WINDOW_FULLTILE_SHUTTLE)
 	canSmoothWith = list(SMOOTH_GROUP_TITANIUM_WALLS, SMOOTH_GROUP_AIRLOCK, SMOOTH_GROUP_SHUTTLE_PARTS, SMOOTH_GROUP_WINDOW_FULLTILE_SHUTTLE)
 
+/turf/simulated/wall/mineral/titanium/copyTurf(turf/T)
+	. = ..()
+	T.transform = transform
+
 /turf/simulated/wall/mineral/titanium/nodiagonal
 	icon_state = "map-shuttle_nd"
 	smoothing_flags = SMOOTH_BITMASK
@@ -225,28 +229,8 @@
 	icon_state = "map-overspace"
 	fixed_underlay = list("space" = TRUE)
 
-//sub-type to be used for interior shuttle walls
-//won't get an underlay of the destination turf on shuttle move
-/turf/simulated/wall/mineral/titanium/interior/copyTurf(turf/T)
-	if(T.type != type)
-		T.ChangeTurf(type)
-		if(length(underlays))
-			T.underlays = underlays
-	if(T.icon_state != icon_state)
-		T.icon_state = icon_state
-	if(T.icon != icon)
-		T.icon = icon
-	if(color)
-		T.atom_colours = atom_colours.Copy()
-		T.update_atom_colour()
-	if(T.dir != dir)
-		T.setDir(dir)
-	T.transform = transform
-	return T
-
-/turf/simulated/wall/mineral/titanium/copyTurf(turf/T)
-	. = ..()
-	T.transform = transform
+/// Used when we don't want to smooth with outer walls
+/turf/simulated/wall/mineral/titanium/interior
 
 /turf/simulated/wall/mineral/titanium/survival
 	name = "pod wall"
@@ -276,6 +260,10 @@
 	smoothing_groups = list(SMOOTH_GROUP_PLASTITANIUM_WALLS)
 	canSmoothWith = list(SMOOTH_GROUP_PLASTITANIUM_WALLS, SMOOTH_GROUP_AIRLOCK, SMOOTH_GROUP_SHUTTLE_PARTS)
 
+/turf/simulated/wall/mineral/plastitanium/copyTurf(turf/T)
+	. = ..()
+	T.transform = transform
+
 /turf/simulated/wall/mineral/plastitanium/nodiagonal
 	icon_state = "map-shuttle_nd"
 	smoothing_flags = SMOOTH_BITMASK
@@ -289,24 +277,5 @@
 	icon_state = "map-overspace"
 	fixed_underlay = list("space" = TRUE)
 
-//have to copypaste this code
-/turf/simulated/wall/mineral/plastitanium/interior/copyTurf(turf/T)
-	if(T.type != type)
-		T.ChangeTurf(type)
-		if(length(underlays))
-			T.underlays = underlays
-	if(T.icon_state != icon_state)
-		T.icon_state = icon_state
-	if(T.icon != icon)
-		T.icon = icon
-	if(color)
-		T.atom_colours = atom_colours.Copy()
-		T.update_atom_colour()
-	if(T.dir != dir)
-		T.setDir(dir)
-	T.transform = transform
-	return T
-
-/turf/simulated/wall/mineral/plastitanium/copyTurf(turf/T)
-	. = ..()
-	T.transform = transform
+/// Used when we don't want to smooth with outer walls
+/turf/simulated/wall/mineral/plastitanium/interior
diff --git a/code/game/turfs/space/space_turf.dm b/code/game/turfs/space/space_turf.dm
index 05b801ef4c2..647bbbd6d58 100644
--- a/code/game/turfs/space/space_turf.dm
+++ b/code/game/turfs/space/space_turf.dm
@@ -45,7 +45,7 @@
 		update_light()
 
 	if(opacity)
-		has_opaque_atom = TRUE
+		directional_opacity = ALL_CARDINALS
 
 	return INITIALIZE_HINT_NORMAL
 
diff --git a/code/game/turfs/turf.dm b/code/game/turfs/turf.dm
index db85c94865b..d28b16731bb 100644
--- a/code/game/turfs/turf.dm
+++ b/code/game/turfs/turf.dm
@@ -67,14 +67,18 @@
 
 	/// Is the lighting on this turf inited
 	var/tmp/lighting_corners_initialised = FALSE
-	/// List of light sources affecting this turf.
-	var/tmp/list/datum/light_source/affecting_lights
 	/// The lighting Object affecting us
-	var/tmp/atom/movable/lighting_object/lighting_object
-	/// A list of our lighting corners.
-	var/tmp/list/datum/lighting_corner/corners
-	/// Not to be confused with opacity, this will be TRUE if there's any opaque atom on the tile.
-	var/tmp/has_opaque_atom = FALSE
+	var/tmp/datum/lighting_object/lighting_object
+	/// Lighting Corner datums.
+	var/tmp/datum/lighting_corner/lighting_corner_NE
+	var/tmp/datum/lighting_corner/lighting_corner_SE
+	var/tmp/datum/lighting_corner/lighting_corner_SW
+	var/tmp/datum/lighting_corner/lighting_corner_NW
+
+	/// Which directions does this turf block the vision of, taking into account both the turf's opacity and the movable opacity_sources.
+	var/directional_opacity = NONE
+	/// Lazylist of movable atoms providing opacity sources.
+	var/list/atom/movable/opacity_sources
 
 	/// The general behavior of atmos on this tile.
 	var/atmos_mode = ATMOS_MODE_SEALED
@@ -128,11 +132,11 @@
 	if(!IS_DYNAMIC_LIGHTING(src) && IS_DYNAMIC_LIGHTING(A))
 		add_overlay(/obj/effect/fullbright)
 
-	if(light_power && light_range)
+	if(light_range && light_power)
 		update_light()
 
 	if(opacity)
-		has_opaque_atom = TRUE
+		directional_opacity = ALL_CARDINALS
 
 	initialize_milla()
 
@@ -238,11 +242,6 @@
 		if(!O.lastarea)
 			O.lastarea = get_area(O.loc)
 
-	// If an opaque movable atom moves around we need to potentially update visibility.
-	if(A.opacity)
-		has_opaque_atom = TRUE // Make sure to do this before reconsider_lights(), incase we're on instant updates. Guaranteed to be on in this case.
-		reconsider_lights()
-
 	if((!(A) || !(src in A.locs)))
 		return
 
@@ -315,13 +314,14 @@
 		return src
 
 	set_light(0)
-	var/old_opacity = opacity
-	var/old_dynamic_lighting = dynamic_lighting
-	var/old_affecting_lights = affecting_lights
 	var/old_lighting_object = lighting_object
 	var/old_blueprint_data = blueprint_data
 	var/old_obscured = obscured
-	var/old_corners = corners
+	var/old_lighting_corner_NE = lighting_corner_NE
+	var/old_lighting_corner_SE = lighting_corner_SE
+	var/old_lighting_corner_SW = lighting_corner_SW
+	var/old_lighting_corner_NW = lighting_corner_NW
+	var/old_directional_opacity = directional_opacity
 
 	BeforeChange()
 	SEND_SIGNAL(src, COMSIG_TURF_CHANGE, path, defer_change, keep_icon, ignore_air, copy_existing_baseturf)
@@ -352,24 +352,26 @@
 	W.blueprint_data = old_blueprint_data
 	W.pressure_overlay = old_pressure_overlay
 
-	recalc_atom_opacity()
+	lighting_corner_NE = old_lighting_corner_NE
+	lighting_corner_SE = old_lighting_corner_SE
+	lighting_corner_SW = old_lighting_corner_SW
+	lighting_corner_NW = old_lighting_corner_NW
+
+	if(!W.dynamic_lighting)
+		W.lighting_build_overlay()
+	else
+		W.lighting_clear_overlay()
 
 	if(SSlighting.initialized)
-		recalc_atom_opacity()
-		lighting_object = old_lighting_object
-		affecting_lights = old_affecting_lights
-		corners = old_corners
-		if(old_opacity != opacity || dynamic_lighting != old_dynamic_lighting)
-			reconsider_lights()
+		W.lighting_object = old_lighting_object
+		directional_opacity = old_directional_opacity
+		recalculate_directional_opacity()
 
-		if(dynamic_lighting != old_dynamic_lighting)
-			if(IS_DYNAMIC_LIGHTING(src))
-				lighting_build_overlay()
-			else
-				lighting_clear_overlay()
+		if(lighting_object && !lighting_object.needs_update)
+			lighting_object.update()
 
-		for(var/turf/space/S in RANGE_TURFS(1, src)) //RANGE_TURFS is in code\__HELPERS\game.dm
-			S.update_starlight()
+		for(var/turf/space/space_tile in RANGE_TURFS(1, src))
+			space_tile.update_starlight()
 
 	obscured = old_obscured
 
@@ -616,7 +618,7 @@
 		add_blueprints(AM)
 
 /turf/proc/empty(turf_type = /turf/space)
-	// Remove all atoms except observers, landmarks, docking ports, and (un)`simulated` atoms (lighting overlays)
+	// Remove all atoms except observers, landmarks, docking ports
 	var/turf/T0 = src
 	for(var/X in T0.GetAllContents())
 		var/atom/A = X
diff --git a/code/modules/clothing/glasses/glasses.dm b/code/modules/clothing/glasses/glasses.dm
index ce8312ebe2a..cf5d59154c4 100644
--- a/code/modules/clothing/glasses/glasses.dm
+++ b/code/modules/clothing/glasses/glasses.dm
@@ -250,7 +250,7 @@
 	icon_state = "material"
 	item_state = "glasses"
 	origin_tech = "magnets=3;engineering=3"
-	vision_flags = SEE_OBJS
+	vision_flags = SEE_OBJS | SEE_TURFS
 
 	sprite_sheets = list(
 		"Vox" = 'icons/mob/clothing/species/vox/eyes.dmi',
diff --git a/code/modules/clothing/head/helmet.dm b/code/modules/clothing/head/helmet.dm
index 408f91402fa..3d113d02a92 100644
--- a/code/modules/clothing/head/helmet.dm
+++ b/code/modules/clothing/head/helmet.dm
@@ -69,7 +69,7 @@
 /obj/item/clothing/head/helmet/material
 	name = "material visor helmet"
 	desc = "A helmet with a built-in material scanning visor."
-	vision_flags = SEE_OBJS
+	vision_flags = SEE_OBJS | SEE_TURFS
 
 /obj/item/clothing/head/helmet/night
 	name = "night-vision helmet"
diff --git a/code/modules/events/spacevine.dm b/code/modules/events/spacevine.dm
index 4801fd332b2..50fd19bdadc 100644
--- a/code/modules/events/spacevine.dm
+++ b/code/modules/events/spacevine.dm
@@ -273,7 +273,7 @@
 	quality = SPACEVINE_MUTATION_POSITIVE
 
 /datum/spacevine_mutation/transparency/on_grow(obj/structure/spacevine/holder)
-	holder.set_opacity(0)
+	holder.set_opacity(FALSE)
 	holder.alpha = 125
 
 /datum/spacevine_mutation/thorns
@@ -446,7 +446,7 @@
 			qdel(master)
 	master = null
 	mutations.Cut()
-	set_opacity(0)
+	set_opacity(FALSE)
 	if(has_buckled_mobs())
 		unbuckle_all_mobs(force = TRUE)
 	return ..()
@@ -643,7 +643,7 @@
 	if(!energy)
 		icon_state = pick("Med1", "Med2", "Med3")
 		energy = 1
-		set_opacity(1)
+		set_opacity(TRUE)
 	else
 		icon_state = pick("Hvy1", "Hvy2", "Hvy3")
 		energy = 2
diff --git a/code/modules/lighting/lighting_atom.dm b/code/modules/lighting/lighting_atom.dm
index b3578178ab3..b815704206c 100644
--- a/code/modules/lighting/lighting_atom.dm
+++ b/code/modules/lighting/lighting_atom.dm
@@ -48,25 +48,36 @@
 /atom/proc/extinguish_light(force = FALSE)
 	return
 
-// Should always be used to change the opacity of an atom.
-// It notifies (potentially) affected light sources so they can update (if needed).
+/**
+  * Updates the atom's opacity value.
+  *
+  * This exists to act as a hook for associated behavior.
+  * It notifies (potentially) affected light sources so they can update (if needed).
+  */
 /atom/proc/set_opacity(new_opacity)
 	if(new_opacity == opacity)
 		return
 
+	SEND_SIGNAL(src, COMSIG_ATOM_SET_OPACITY, new_opacity)
+	. = opacity
 	opacity = new_opacity
-	var/turf/T = loc
-	if(!isturf(T))
+
+/atom/movable/set_opacity(new_opacity)
+	. = ..()
+	if(isnull(.) || !isturf(loc))
 		return
 
-	if(new_opacity)
-		T.has_opaque_atom = TRUE
-		T.reconsider_lights()
+	if(opacity)
+		AddElement(/datum/element/light_blocking)
 	else
-		var/old_has_opaque_atom = T.has_opaque_atom
-		T.recalc_atom_opacity()
-		if(old_has_opaque_atom != T.has_opaque_atom)
-			T.reconsider_lights()
+		RemoveElement(/datum/element/light_blocking)
+
+/turf/set_opacity(new_opacity)
+	. = ..()
+	if(isnull(.))
+		return
+
+	recalculate_directional_opacity()
 
 /atom/proc/flash_lighting_fx(_range = FLASH_LIGHT_RANGE, _power = FLASH_LIGHT_POWER, _color = LIGHT_COLOR_WHITE, _duration = FLASH_LIGHT_DURATION, _reset_lighting = TRUE)
 	return
diff --git a/code/modules/lighting/lighting_corner.dm b/code/modules/lighting/lighting_corner.dm
index 57302b5b168..96fec530e81 100644
--- a/code/modules/lighting/lighting_corner.dm
+++ b/code/modules/lighting/lighting_corner.dm
@@ -2,34 +2,37 @@
 // And corners get shared between multiple turfs (unless you're on the corners of the map, then 1 corner doesn't).
 // For the record: these should never ever ever be deleted, even if the turf doesn't have dynamic lighting.
 
-// This list is what the code that assigns corners listens to, the order in this list is the order in which corners are added to the /turf/corners list.
-GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST, NORTHWEST))
-
 /datum/lighting_corner
-	var/list/turf/masters
-	var/list/datum/light_source/affecting // Light sources affecting us.
-	var/active                            = FALSE  // TRUE if one of our masters has dynamic lighting.
+	/// Light sources affecting us.
+	var/list/datum/light_source/affecting
 
-	var/x     = 0
-	var/y     = 0
-	var/z     = 0
+	var/x = 0
+	var/y = 0
 
+	var/turf/master_NE
+	var/turf/master_SE
+	var/turf/master_SW
+	var/turf/master_NW
+
+	// "raw" color values, changed by update_lumcount()
 	var/lum_r = 0
 	var/lum_g = 0
 	var/lum_b = 0
 
-	var/needs_update = FALSE
+	// true color values, guaranteed to be between 0 and 1
+	var/cache_r = LIGHTING_SOFT_THRESHOLD
+	var/cache_g = LIGHTING_SOFT_THRESHOLD
+	var/cache_b = LIGHTING_SOFT_THRESHOLD
 
-	var/cache_r  = LIGHTING_SOFT_THRESHOLD
-	var/cache_g  = LIGHTING_SOFT_THRESHOLD
-	var/cache_b  = LIGHTING_SOFT_THRESHOLD
-	var/cache_mx = 0
+	/// the maximum of lum_r, lum_g, and lum_b. if this is > 1 then the three cached color values are divided by this
+	var/largest_color_luminosity = 0
+
+	/// whether we are to be added to SSlighting's corners_queue list for an update
+	var/needs_update = FALSE
 
 /datum/lighting_corner/New(turf/new_turf, diagonal)
 	. = ..()
-	masters = list()
-	masters[new_turf] = turn(diagonal, 180)
-	z = new_turf.z
+	save_master(new_turf, turn(diagonal, 180))
 
 	var/vertical   = diagonal & ~(diagonal - 1) // The horizontal directions (4 and 8) are bigger than the vertical ones (1 and 2), so we can reliably say the lsb is the horizontal direction.
 	var/horizontal = diagonal & ~vertical       // Now that we know the horizontal one we can get the vertical one.
@@ -40,50 +43,49 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	// My initial plan was to make this loop through a list of all the dirs (horizontal, vertical, diagonal).
 	// Issue being that the only way I could think of doing it was very messy, slow and honestly overengineered.
 	// So we'll have this hardcode instead.
-	var/turf/T
-	var/i
+	var/turf/new_master_turf
 
 	// Diagonal one is easy.
-	T = get_step(new_turf, diagonal)
-	if(T) // In case we're on the map's border.
-		if(!T.corners)
-			T.corners = list(null, null, null, null)
-
-		masters[T]   = diagonal
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(diagonal, 180))
-		T.corners[i] = src
+	new_master_turf = get_step(new_turf, diagonal)
+	if(new_master_turf) // In case we're on the map's border.
+		save_master(new_master_turf, diagonal)
 
 	// Now the horizontal one.
-	T = get_step(new_turf, horizontal)
-	if(T) // Ditto.
-		if(!T.corners)
-			T.corners = list(null, null, null, null)
-
-		masters[T]   = ((T.x > x) ? EAST : WEST) | ((T.y > y) ? NORTH : SOUTH) // Get the dir based on coordinates.
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(masters[T], 180))
-		T.corners[i] = src
+	new_master_turf = get_step(new_turf, horizontal)
+	if(new_master_turf) // Ditto.
+		save_master(new_master_turf, ((new_master_turf.x > x) ? EAST : WEST) | ((new_master_turf.y > y) ? NORTH : SOUTH)) // Get the dir based on coordinates.
 
 	// And finally the vertical one.
-	T = get_step(new_turf, vertical)
-	if(T)
-		if(!T.corners)
-			T.corners = list(null, null, null, null)
+	new_master_turf = get_step(new_turf, vertical)
+	if(new_master_turf)
+		save_master(new_master_turf, ((new_master_turf.x > x) ? EAST : WEST) | ((new_master_turf.y > y) ? NORTH : SOUTH)) // Get the dir based on coordinates.
 
-		masters[T]   = ((T.x > x) ? EAST : WEST) | ((T.y > y) ? NORTH : SOUTH) // Get the dir based on coordinates.
-		i            = GLOB.LIGHTING_CORNER_DIAGONAL.Find(turn(masters[T], 180))
-		T.corners[i] = src
+/datum/lighting_corner/proc/save_master(turf/master, dir)
+	switch(dir)
+		if(NORTHEAST)
+			master_NE = master
+			master.lighting_corner_SW = src
+		if(SOUTHEAST)
+			master_SE = master
+			master.lighting_corner_NW = src
+		if(SOUTHWEST)
+			master_SW = master
+			master.lighting_corner_NE = src
+		if(NORTHWEST)
+			master_NW = master
+			master.lighting_corner_SE = src
 
-	update_active()
+/datum/lighting_corner/proc/self_destruct_if_idle()
+	if(!LAZYLEN(affecting))
+		qdel(src, force = TRUE)
 
-/datum/lighting_corner/proc/update_active()
-	active = FALSE
-	var/turf/T
-	var/thing
-	for(thing in masters)
-		T = thing
-		if(T.lighting_object)
-			active = TRUE
-			return
+/datum/lighting_corner/proc/vis_update()
+	for(var/datum/light_source/light_source as anything in affecting)
+		light_source.vis_update()
+
+/datum/lighting_corner/proc/full_update()
+	for(var/datum/light_source/light_source as anything in affecting)
+		light_source.recalc_corner(src)
 
 // God that was a mess, now to do the rest of the corner code! Hooray!
 /datum/lighting_corner/proc/update_lumcount(delta_r, delta_g, delta_b)
@@ -104,13 +106,13 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	var/lum_r = src.lum_r
 	var/lum_g = src.lum_g
 	var/lum_b = src.lum_b
-	var/mx = max(lum_r, lum_g, lum_b) // Scale it so one of them is the strongest lum, if it is above 1.
+	var/largest_color_luminosity = max(lum_r, lum_g, lum_b) // Scale it so one of them is the strongest lum, if it is above 1.
 	. = 1 // factor
-	if(mx > 1)
-		. = 1 / mx
+	if(largest_color_luminosity > 1)
+		. = 1 / largest_color_luminosity
 
 	#if LIGHTING_SOFT_THRESHOLD != 0
-	else if(mx < LIGHTING_SOFT_THRESHOLD)
+	else if(largest_color_luminosity < LIGHTING_SOFT_THRESHOLD)
 		. = 0 // 0 means soft lighting.
 
 	cache_r  = round(lum_r * ., LIGHTING_ROUND_VALUE) || LIGHTING_SOFT_THRESHOLD
@@ -121,13 +123,30 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	cache_g  = round(lum_g * ., LIGHTING_ROUND_VALUE)
 	cache_b  = round(lum_b * ., LIGHTING_ROUND_VALUE)
 	#endif
-	cache_mx = round(mx, LIGHTING_ROUND_VALUE)
 
-	for(var/TT in masters)
-		var/turf/T = TT
-		if(T.lighting_object && !T.lighting_object.needs_update)
-			T.lighting_object.needs_update = TRUE
-			SSlighting.objects_queue += T.lighting_object
+	src.largest_color_luminosity = round(largest_color_luminosity, LIGHTING_ROUND_VALUE)
+
+	var/datum/lighting_object/lighting_object = master_NE?.lighting_object
+	if(lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_SE?.lighting_object
+	if(lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_SW?.lighting_object
+	if(lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	lighting_object = master_NW?.lighting_object
+	if(lighting_object && !lighting_object.needs_update)
+		lighting_object.needs_update = TRUE
+		SSlighting.objects_queue += lighting_object
+
+	self_destruct_if_idle()
 
 
 /datum/lighting_corner/dummy/New()
@@ -138,6 +157,23 @@ GLOBAL_LIST_INIT(LIGHTING_CORNER_DIAGONAL, list(NORTHEAST, SOUTHEAST, SOUTHWEST,
 	if(!force)
 		return QDEL_HINT_LETMELIVE
 
-	stack_trace("Attempted qdel of a lighting corner.")
+	for(var/datum/light_source/light_source as anything in affecting)
+		LAZYREMOVE(light_source.effect_str, src)
+	affecting = null
+
+	if(master_NE)
+		master_NE.lighting_corner_SW = null
+		master_NE.lighting_corners_initialised = FALSE
+	if(master_SE)
+		master_SE.lighting_corner_NW = null
+		master_SE.lighting_corners_initialised = FALSE
+	if(master_SW)
+		master_SW.lighting_corner_NE = null
+		master_SW.lighting_corners_initialised = FALSE
+	if(master_NW)
+		master_NW.lighting_corner_SE = null
+		master_NW.lighting_corners_initialised = FALSE
+	if(needs_update)
+		SSlighting.corners_queue -= src
 
 	return ..()
diff --git a/code/modules/lighting/lighting_object.dm b/code/modules/lighting/lighting_object.dm
index df62b5c342e..265c47ca96d 100644
--- a/code/modules/lighting/lighting_object.dm
+++ b/code/modules/lighting/lighting_object.dm
@@ -1,66 +1,45 @@
-/atom/movable/lighting_object
-	name          = ""
-
-	anchored      = TRUE
-
-	icon             = LIGHTING_ICON
-	icon_state       = "transparent"
-	color            = null //we manually set color in init instead
-	plane            = LIGHTING_PLANE
-	mouse_opacity 	 = MOUSE_OPACITY_TRANSPARENT
-	layer            = LIGHTING_LAYER
-	invisibility     = INVISIBILITY_LIGHTING
-	simulated 		 = FALSE
-
+/datum/lighting_object
+	/// the underlay we are currently applying to our turf to apply light
+	var/mutable_appearance/current_underlay
+	/// whether we are already in the SSlighting.objects_queue list
 	var/needs_update = FALSE
-	var/turf/myturf
+	/// the turf that our light is applied to
+	var/turf/affected_turf
 
-/atom/movable/lighting_object/Initialize(mapload)
+/datum/lighting_object/New(turf/source)
+	if(!isturf(source))
+		qdel(src, force = TRUE)
+		stack_trace("a lighting object was assigned to [source], a non turf!")
+		return
 	. = ..()
-	verbs.Cut()
-	//We avoid setting this in the base as if we do then the parent atom handling will add_atom_color it and that
-	//is totally unsuitable for this object, as we are always changing it's colour manually
-	color = LIGHTING_BASE_MATRIX
+	current_underlay = mutable_appearance(LIGHTING_ICON, "transparent", -LIGHTING_LAYER, LIGHTING_PLANE, 255, RESET_COLOR | RESET_ALPHA | RESET_TRANSFORM)
 
-	myturf = loc
-	if(myturf.lighting_object)
-		qdel(myturf.lighting_object, force = TRUE)
-	myturf.lighting_object = src
-	myturf.luminosity = 0
+	affected_turf = source
+	if(affected_turf.lighting_object)
+		qdel(affected_turf.lighting_object, force = TRUE)
+		stack_trace("a lighting object was assigned to a turf that already had a lighting object!")
 
-	for(var/turf/space/S in RANGE_TURFS(1, src)) //RANGE_TURFS is in code\__HELPERS\game.dm
-		S.update_starlight()
+	affected_turf.lighting_object = src
+	affected_turf.luminosity = 0
+
+	for(var/turf/space/space_tile in RANGE_TURFS(1, affected_turf))
+		space_tile.update_starlight()
 
 	needs_update = TRUE
 	SSlighting.objects_queue += src
 
-/atom/movable/lighting_object/Destroy(force)
-	if(force)
-		SSlighting.objects_queue -= src
-		if(loc != myturf)
-			var/turf/oldturf = get_turf(myturf)
-			var/turf/newturf = get_turf(loc)
-			stack_trace("A lighting object was qdeleted with a different loc then it is suppose to have ([COORD(oldturf)] -> [COORD(newturf)])")
-		if(isturf(myturf))
-			myturf.lighting_object = null
-			myturf.luminosity = 1
-		myturf = null
-
-		return ..()
-
-	else
+/datum/lighting_object/Destroy(force)
+	if(!force)
 		return QDEL_HINT_LETMELIVE
+	SSlighting.objects_queue -= src
+	if(isturf(affected_turf))
+		affected_turf.lighting_object = null
+		affected_turf.luminosity = 1
+		affected_turf.underlays -= current_underlay
+	affected_turf = null
+	return ..()
 
-/atom/movable/lighting_object/proc/update()
-	if(loc != myturf)
-		if(loc)
-			var/turf/oldturf = get_turf(myturf)
-			var/turf/newturf = get_turf(loc)
-			warning("A lighting object realised it's loc had changed in update() ([myturf]\[[myturf ? myturf.type : "null"]]([COORD(oldturf)]) -> [loc]\[[ loc ? loc.type : "null"]]([COORD(newturf)]))!")
-
-		qdel(src, TRUE)
-		return
-
+/datum/lighting_object/proc/update()
 	// To the future coder who sees this and thinks
 	// "Why didn't he just use a loop?"
 	// Well my man, it's because the loop performed like shit.
@@ -69,37 +48,30 @@
 	// Oh it's also shorter line wise.
 	// Including with these comments.
 
-	// See LIGHTING_CORNER_DIAGONAL in lighting_corner.dm for why these values are what they are.
 	var/static/datum/lighting_corner/dummy/dummy_lighting_corner = new
 
-	var/list/corners = myturf.corners
-	var/datum/lighting_corner/cr = dummy_lighting_corner
-	var/datum/lighting_corner/cg = dummy_lighting_corner
-	var/datum/lighting_corner/cb = dummy_lighting_corner
-	var/datum/lighting_corner/ca = dummy_lighting_corner
-	if(corners) //done this way for speed
-		cr = corners[3] || dummy_lighting_corner
-		cg = corners[2] || dummy_lighting_corner
-		cb = corners[4] || dummy_lighting_corner
-		ca = corners[1] || dummy_lighting_corner
+	var/datum/lighting_corner/red_corner = affected_turf.lighting_corner_SW || dummy_lighting_corner
+	var/datum/lighting_corner/green_corner = affected_turf.lighting_corner_SE || dummy_lighting_corner
+	var/datum/lighting_corner/blue_corner = affected_turf.lighting_corner_NW || dummy_lighting_corner
+	var/datum/lighting_corner/alpha_corner = affected_turf.lighting_corner_NE || dummy_lighting_corner
 
-	var/max = max(cr.cache_mx, cg.cache_mx, cb.cache_mx, ca.cache_mx)
+	var/max = max(red_corner.largest_color_luminosity, green_corner.largest_color_luminosity, blue_corner.largest_color_luminosity, alpha_corner.largest_color_luminosity)
 
-	var/rr = cr.cache_r
-	var/rg = cr.cache_g
-	var/rb = cr.cache_b
+	var/rr = red_corner.cache_r
+	var/rg = red_corner.cache_g
+	var/rb = red_corner.cache_b
 
-	var/gr = cg.cache_r
-	var/gg = cg.cache_g
-	var/gb = cg.cache_b
+	var/gr = green_corner.cache_r
+	var/gg = green_corner.cache_g
+	var/gb = green_corner.cache_b
 
-	var/br = cb.cache_r
-	var/bg = cb.cache_g
-	var/bb = cb.cache_b
+	var/br = blue_corner.cache_r
+	var/bg = blue_corner.cache_g
+	var/bb = blue_corner.cache_b
 
-	var/ar = ca.cache_r
-	var/ag = ca.cache_g
-	var/ab = ca.cache_b
+	var/ar = alpha_corner.cache_r
+	var/ag = alpha_corner.cache_g
+	var/ab = alpha_corner.cache_b
 
 	#if LIGHTING_SOFT_THRESHOLD != 0
 	var/set_luminosity = max > LIGHTING_SOFT_THRESHOLD
@@ -110,42 +82,26 @@
 	#endif
 
 	if((rr & gr & br & ar) && (rg + gg + bg + ag + rb + gb + bb + ab == 8))
-	//anything that passes the first case is very likely to pass the second, and addition is a little faster in this case
-		icon_state = "transparent"
-		color = null
+		// anything that passes the first case is very likely to pass the second, and addition is a little faster in this case
+		affected_turf.underlays -= current_underlay
+		current_underlay.icon_state = "lighting_transparent"
+		current_underlay.color = null
+		affected_turf.underlays += current_underlay
 	else if(!set_luminosity)
-		icon_state = "dark"
-		color = null
+		affected_turf.underlays -= current_underlay
+		current_underlay.icon_state = "lighting_dark"
+		current_underlay.color = null
+		affected_turf.underlays += current_underlay
 	else
-		icon_state = null
-		color = list(
+		affected_turf.underlays -= current_underlay
+		current_underlay.icon_state = null
+		current_underlay.color = list(
 			rr, rg, rb, 00,
 			gr, gg, gb, 00,
 			br, bg, bb, 00,
 			ar, ag, ab, 00,
 			00, 00, 00, 01
 		)
+		affected_turf.underlays += current_underlay
 
-	luminosity = set_luminosity
-
-// Variety of overrides so the overlays don't get affected by weird things.
-
-/atom/movable/lighting_object/ex_act(severity)
-	return 0
-
-/atom/movable/lighting_object/singularity_act()
-	return
-
-/atom/movable/lighting_object/singularity_pull()
-	return
-
-/atom/movable/lighting_object/blob_act(obj/structure/blob/B)
-	return
-
-/atom/movable/lighting_object/on_changed_z_level(turf/old_turf, turf/new_turf, notify_contents = FALSE)
-	return ..()
-
-// Override here to prevent things accidentally moving around overlays.
-/atom/movable/lighting_object/forceMove(atom/destination, no_tp = FALSE, harderforce = FALSE)
-	if(harderforce)
-		. = ..()
+	affected_turf.luminosity = set_luminosity
diff --git a/code/modules/lighting/lighting_setup.dm b/code/modules/lighting/lighting_setup.dm
index 9923006815f..21828e46840 100644
--- a/code/modules/lighting/lighting_setup.dm
+++ b/code/modules/lighting/lighting_setup.dm
@@ -7,6 +7,6 @@
 			if(!IS_DYNAMIC_LIGHTING(T))
 				continue
 
-			new/atom/movable/lighting_object(T)
+			new /datum/lighting_object(T)
 			CHECK_TICK
 		CHECK_TICK
diff --git a/code/modules/lighting/lighting_source.dm b/code/modules/lighting/lighting_source.dm
index 9302b1fc56b..8741e1bf9cf 100644
--- a/code/modules/lighting/lighting_source.dm
+++ b/code/modules/lighting/lighting_source.dm
@@ -2,14 +2,21 @@
 // These are the main datums that emit light.
 
 /datum/light_source
-	var/atom/top_atom        // The atom we're emitting light from (for example a mob if we're from a flashlight that's being held).
-	var/atom/source_atom     // The atom that we belong to.
+	/// The atom we're emitting light from (for example a mob if we're from a flashlight that's being held).
+	var/atom/top_atom
+	/// The atom that we belong to.
+	var/atom/source_atom
 
-	var/turf/source_turf     // The turf under the above.
-	var/turf/pixel_turf      // The turf the top_atom appears to over.
-	var/light_power    // Intensity of the emitter light.
-	var/light_range      // The range of the emitted light.
-	var/light_color    // The colour of the light, string, decomposed by parse_light_color()
+	/// The turf under the above.
+	var/turf/source_turf
+	/// The turf the top_atom appears to over.
+	var/turf/pixel_turf
+	/// Intensity of the emitter light.
+	var/light_power
+	/// The range of the emitted light.
+	var/light_range
+	/// The colour of the light, string, decomposed by parse_light_color()
+	var/light_color
 
 	// Variables for keeping track of the colour.
 	var/lum_r
@@ -21,12 +28,14 @@
 	var/tmp/applied_lum_g
 	var/tmp/applied_lum_b
 
-	var/list/datum/lighting_corner/effect_str     // List used to store how much we're affecting corners.
-	var/list/turf/affecting_turfs
+	/// List used to store how much we're affecting corners.
+	var/list/datum/lighting_corner/effect_str
 
-	var/applied = FALSE // Whether we have applied our light yet or not.
+	/// Whether we have applied our light yet or not.
+	var/applied = FALSE
 
-	var/needs_update = LIGHTING_NO_UPDATE    // Whether we are queued for an update.
+	/// Whether we are queued for an update.
+	var/needs_update = LIGHTING_NO_UPDATE
 
 
 /datum/light_source/New(atom/owner, atom/top)
@@ -110,55 +119,44 @@
 // The braces and semicolons are there to be able to do this on a single line.
 #define LUM_FALLOFF(C, T) (1 - CLAMP01(sqrt((C.x - T.x) ** 2 + (C.y - T.y) ** 2 + LIGHTING_HEIGHT) / max(1, light_range)))
 
-#define APPLY_CORNER(C)                      \
-	. = LUM_FALLOFF(C, pixel_turf);          \
-	. *= light_power;                        \
-	var/OLD = effect_str[C];                 \
-	effect_str[C] = .;                       \
-	C.update_lumcount                        \
-	(                                        \
-		(. * lum_r) - (OLD * applied_lum_r), \
-		(. * lum_g) - (OLD * applied_lum_g), \
-		(. * lum_b) - (OLD * applied_lum_b)  \
+#define APPLY_CORNER(C)							\
+	. = LUM_FALLOFF(C, pixel_turf);				\
+	. *= light_power;							\
+	var/OLD = effect_str[C];					\
+												\
+	C.update_lumcount							\
+	(											\
+		(. * lum_r) - (OLD * applied_lum_r),	\
+		(. * lum_g) - (OLD * applied_lum_g),	\
+		(. * lum_b) - (OLD * applied_lum_b)		\
+	);											\
+
+#define REMOVE_CORNER(C)						\
+	. = -effect_str[C];							\
+	C.update_lumcount							\
+	(											\
+		. * applied_lum_r,						\
+		. * applied_lum_g,						\
+		. * applied_lum_b						\
 	);
 
-#define REMOVE_CORNER(C)                     \
-	. = -effect_str[C];                      \
-	C.update_lumcount                        \
-	(                                        \
-		. * applied_lum_r,                   \
-		. * applied_lum_g,                   \
-		. * applied_lum_b                    \
-	);
-
-// This is the define used to calculate falloff.
-
+/// This is the define used to calculate falloff.
 /datum/light_source/proc/remove_lum()
 	applied = FALSE
-	var/thing
-	for(thing in affecting_turfs)
-		var/turf/T = thing
-		LAZYREMOVE(T.affecting_lights, src)
-
-	affecting_turfs = null
-
-	var/datum/lighting_corner/C
-	for(thing in effect_str)
-		C = thing
-		REMOVE_CORNER(C)
-
-		LAZYREMOVE(C.affecting, src)
+	for(var/datum/lighting_corner/corner as anything in effect_str)
+		REMOVE_CORNER(corner)
+		LAZYREMOVE(corner.affecting, src)
 
 	effect_str = null
 
-/datum/light_source/proc/recalc_corner(datum/lighting_corner/C)
+/datum/light_source/proc/recalc_corner(datum/lighting_corner/corner)
 	LAZYINITLIST(effect_str)
-	if(effect_str[C]) // Already have one.
-		REMOVE_CORNER(C)
-		effect_str[C] = 0
+	if(effect_str[corner]) // Already have one.
+		REMOVE_CORNER(corner)
+		effect_str[corner] = 0
 
-	APPLY_CORNER(C)
-	UNSETEMPTY(effect_str)
+	APPLY_CORNER(corner)
+	effect_str[corner] = .
 
 /datum/light_source/proc/update_corners()
 	var/update = FALSE
@@ -194,9 +192,9 @@
 		pixel_turf = get_turf_pixel(top_atom)
 		update = TRUE
 	else
-		var/P = get_turf_pixel(top_atom)
-		if(P != pixel_turf)
-			pixel_turf = P
+		var/pixel_loc = get_turf_pixel(top_atom)
+		if(pixel_loc != pixel_turf)
+			pixel_turf = pixel_loc
 			update = TRUE
 
 	if(!isturf(source_turf))
@@ -224,77 +222,56 @@
 		return //nothing's changed
 
 	var/list/datum/lighting_corner/corners = list()
-	var/list/turf/turfs                    = list()
-	var/thing
-	var/datum/lighting_corner/C
-	var/turf/T
+	var/list/turf/turfs = list()
 	if(source_turf)
 		var/oldlum = source_turf.luminosity
 		source_turf.luminosity = CEILING(light_range, 1)
-		for(T in view(CEILING(light_range, 1), source_turf))
-			if((!IS_DYNAMIC_LIGHTING(T) && !T.light_sources))
-				continue
-			if(!T.has_opaque_atom)
+		for(var/turf/T in view(CEILING(light_range, 1), source_turf))
+			if(!IS_OPAQUE_TURF(T))
 				if(!T.lighting_corners_initialised)
 					T.generate_missing_corners()
-				for(thing in T.corners)
-					C = thing
-					corners[C] = 0
+				corners[T.lighting_corner_NE] = 0
+				corners[T.lighting_corner_SE] = 0
+				corners[T.lighting_corner_SW] = 0
+				corners[T.lighting_corner_NW] = 0
 			turfs += T
 		source_turf.luminosity = oldlum
 
-	LAZYINITLIST(affecting_turfs)
-	var/list/L = turfs - affecting_turfs // New turfs, add us to the affecting lights of them.
-	affecting_turfs += L
-	for(thing in L)
-		T = thing
-		LAZYADD(T.affecting_lights, src)
-
-	L = affecting_turfs - turfs // Now-gone turfs, remove us from the affecting lights.
-	affecting_turfs -= L
-	for(thing in L)
-		T = thing
-		LAZYREMOVE(T.affecting_lights, src)
+	var/list/datum/lighting_corner/new_corners = (corners - effect_str)
 
 	LAZYINITLIST(effect_str)
 	if(needs_update == LIGHTING_VIS_UPDATE)
-		for(thing in  corners - effect_str) // New corners
-			C = thing
-			LAZYADD(C.affecting, src)
-			if(!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for(var/datum/lighting_corner/corner as anything in new_corners)
+			APPLY_CORNER(corner)
+			if(. != 0)
+				LAZYADD(corner.affecting, src)
+				effect_str[corner] = .
 	else
-		L = corners - effect_str
-		for(thing in L) // New corners
-			C = thing
-			LAZYADD(C.affecting, src)
-			if(!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for(var/datum/lighting_corner/corner as anything in new_corners)
+			APPLY_CORNER(corner)
+			if(. != 0)
+				LAZYADD(corner.affecting, src)
+				effect_str[corner] = .
 
-		for(thing in corners - L) // Existing corners
-			C = thing
-			if(!C.active)
-				effect_str[C] = 0
-				continue
-			APPLY_CORNER(C)
+		for(var/datum/lighting_corner/corner as anything in corners - new_corners) // Existing corners
+			APPLY_CORNER(corner)
+			if(. != 0)
+				effect_str[corner] = .
+			else
+				LAZYREMOVE(corner.affecting, src)
+				effect_str -= corner
 
-	L = effect_str - corners
-	for(thing in L) // Old, now gone, corners.
-		C = thing
-		REMOVE_CORNER(C)
-		LAZYREMOVE(C.affecting, src)
-	effect_str -= L
+	var/list/datum/lighting_corner/gone_corners = effect_str - corners
+	for(var/datum/lighting_corner/corner as anything in gone_corners)
+		REMOVE_CORNER(corner)
+		LAZYREMOVE(corner.affecting, src)
+	effect_str -= gone_corners
 
 	applied_lum_r = lum_r
 	applied_lum_g = lum_g
 	applied_lum_b = lum_b
 
 	UNSETEMPTY(effect_str)
-	UNSETEMPTY(affecting_turfs)
 
 #undef EFFECT_UPDATE
 #undef LUM_FALLOFF
diff --git a/code/modules/lighting/lighting_turf.dm b/code/modules/lighting/lighting_turf.dm
index 6237548bfc3..76b3c78bfae 100644
--- a/code/modules/lighting/lighting_turf.dm
+++ b/code/modules/lighting/lighting_turf.dm
@@ -1,49 +1,20 @@
 // Causes any affecting light sources to be queued for a visibility update, for example a door got opened.
 /turf/proc/reconsider_lights()
-	var/datum/light_source/L
-	var/thing
-	for(thing in affecting_lights)
-		L = thing
-		L.vis_update()
+	lighting_corner_NE?.vis_update()
+	lighting_corner_SE?.vis_update()
+	lighting_corner_SW?.vis_update()
+	lighting_corner_NW?.vis_update()
 
 /turf/proc/lighting_clear_overlay()
 	if(lighting_object)
-		qdel(lighting_object, TRUE)
-
-	var/datum/lighting_corner/C
-	var/thing
-	for(thing in corners)
-		if(!thing)
-			continue
-		C = thing
-		C.update_active()
+		qdel(lighting_object, force = TRUE)
 
 // Builds a lighting object for us, but only if our area is dynamic.
 /turf/proc/lighting_build_overlay()
 	if(lighting_object)
-		qdel(lighting_object,force=TRUE) //Shitty fix for lighting objects persisting after death
+		qdel(lighting_object, force = TRUE) // Shitty fix for lighting objects persisting after death
 
-	var/area/A = loc
-	if(!IS_DYNAMIC_LIGHTING(A) && !light_sources)
-		return
-
-	if(!lighting_corners_initialised)
-		generate_missing_corners()
-
-	new/atom/movable/lighting_object(src)
-
-	var/thing
-	var/datum/lighting_corner/C
-	var/datum/light_source/S
-	for(thing in corners)
-		if(!thing)
-			continue
-		C = thing
-		if(!C.active) // We would activate the corner, calculate the lighting for it.
-			for(thing in C.affecting)
-				S = thing
-				S.recalc_corner(C)
-			C.active = TRUE
+	new /datum/lighting_object(src)
 
 // Used to get a scaled lumcount.
 /turf/proc/get_lumcount(minlum = 0, maxlum = 1)
@@ -51,13 +22,19 @@
 		return 1
 
 	var/totallums = 0
-	var/thing
-	var/datum/lighting_corner/L
-	for(thing in corners)
-		if(!thing)
-			continue
-		L = thing
-		totallums += L.lum_r + L.lum_b + L.lum_g
+	var/datum/lighting_corner/corner
+	corner = lighting_corner_NE
+	if(corner)
+		totallums += corner.lum_r + corner.lum_b + corner.lum_g
+	corner = lighting_corner_SE
+	if(corner)
+		totallums += corner.lum_r + corner.lum_b + corner.lum_g
+	corner = lighting_corner_SW
+	if(corner)
+		totallums += corner.lum_r + corner.lum_b + corner.lum_g
+	corner = lighting_corner_NW
+	if(corner)
+		totallums += corner.lum_r + corner.lum_b + corner.lum_g
 
 	totallums /= 12 // 4 corners, each with 3 channels, get the average.
 
@@ -73,23 +50,39 @@
 	if(!lighting_object)
 		return FALSE
 
-	return !lighting_object.luminosity
+	return !luminosity
 
-// Can't think of a good name, this proc will recalculate the has_opaque_atom variable.
-/turf/proc/recalc_atom_opacity()
-	has_opaque_atom = opacity
-	if(!has_opaque_atom)
-		for(var/atom/A in src.contents) // Loop through every movable atom on our tile PLUS ourselves (we matter too...)
-			if(A.opacity)
-				has_opaque_atom = TRUE
-				break
+/// Proc to add movable sources of opacity on the turf and let it handle lighting code.
+/turf/proc/add_opacity_source(atom/movable/new_source)
+	LAZYADD(opacity_sources, new_source)
+	if(opacity)
+		return
+	recalculate_directional_opacity()
 
-/turf/Exited(atom/movable/Obj, direction)
-	. = ..()
+/// Proc to remove movable sources of opacity on the turf and let it handle lighting code.
+/turf/proc/remove_opacity_source(atom/movable/old_source)
+	LAZYREMOVE(opacity_sources, old_source)
+	if(opacity) // Still opaque, no need to worry on updating.
+		return
+	recalculate_directional_opacity()
 
-	if(Obj && Obj.opacity)
-		recalc_atom_opacity() // Make sure to do this before reconsider_lights(), incase we're on instant updates.
-		reconsider_lights()
+/// Calculate on which directions this turfs block view.
+/turf/proc/recalculate_directional_opacity()
+	. = directional_opacity
+	if(opacity)
+		directional_opacity = ALL_CARDINALS
+		if(. != directional_opacity)
+			reconsider_lights()
+		return
+	directional_opacity = NONE
+	for(var/atom/movable/opacity_source in opacity_sources)
+		if(opacity_source.flags & ON_BORDER)
+			directional_opacity |= opacity_source.dir
+		else // If fulltile and opaque, then the whole tile blocks view, no need to continue checking.
+			directional_opacity = ALL_CARDINALS
+			break
+	if(. != directional_opacity && (. == ALL_CARDINALS || directional_opacity == ALL_CARDINALS))
+		reconsider_lights() // The lighting system only cares whether the tile is fully concealed from all directions or not.
 
 /turf/proc/change_area(area/old_area, area/new_area)
 	if(SSlighting.initialized)
@@ -102,14 +95,16 @@
 		machine.reregister_machine()
 
 /turf/proc/generate_missing_corners()
-	if(!IS_DYNAMIC_LIGHTING(src) && !light_sources)
-		return
+	if(!lighting_corner_NE)
+		lighting_corner_NE = new /datum/lighting_corner(src, NORTH | EAST)
+
+	if(!lighting_corner_SE)
+		lighting_corner_SE = new /datum/lighting_corner(src, SOUTH | EAST)
+
+	if(!lighting_corner_SW)
+		lighting_corner_SW = new /datum/lighting_corner(src, SOUTH | WEST)
+
+	if(!lighting_corner_NW)
+		lighting_corner_NW = new /datum/lighting_corner(src, NORTH | WEST)
+
 	lighting_corners_initialised = TRUE
-	if(!corners)
-		corners = list(null, null, null, null)
-
-	for(var/i = 1 to 4)
-		if(corners[i]) // Already have a corner on this direction.
-			continue
-
-		corners[i] = new/datum/lighting_corner(src, GLOB.LIGHTING_CORNER_DIAGONAL[i])
diff --git a/code/modules/mob/living/simple_animal/hostile/hostile.dm b/code/modules/mob/living/simple_animal/hostile/hostile.dm
index da97915a8a7..3a424121441 100644
--- a/code/modules/mob/living/simple_animal/hostile/hostile.dm
+++ b/code/modules/mob/living/simple_animal/hostile/hostile.dm
@@ -188,7 +188,7 @@
 
 // Please do not add one-off mob AIs here, but override this function for your mob
 /mob/living/simple_animal/hostile/CanAttack(atom/the_target)//Can we actually attack a possible target?
-	if(isturf(the_target) || !the_target || the_target.type == /atom/movable/lighting_object) // bail out on invalids
+	if(isturf(the_target) || !the_target) // bail out on invalids
 		return FALSE
 
 	if(ismob(the_target)) //Target is in godmode, ignore it.
diff --git a/code/modules/mob/living/simple_animal/hostile/mushroom.dm b/code/modules/mob/living/simple_animal/hostile/mushroom.dm
index ce5dc0764cc..806a8197038 100644
--- a/code/modules/mob/living/simple_animal/hostile/mushroom.dm
+++ b/code/modules/mob/living/simple_animal/hostile/mushroom.dm
@@ -59,7 +59,7 @@
 	health = maxHealth
 
 /mob/living/simple_animal/hostile/mushroom/CanAttack(atom/the_target) // Mushroom-specific version of CanAttack to handle stupid attack_same = 2 crap so we don't have to do it for literally every single simple_animal/hostile because this shit never gets spawned
-	if(!the_target || isturf(the_target) || istype(the_target, /atom/movable/lighting_object))
+	if(!the_target || isturf(the_target))
 		return FALSE
 
 	if(see_invisible < the_target.invisibility)//Target's invisible to us, forget it
diff --git a/code/modules/paperwork/photography.dm b/code/modules/paperwork/photography.dm
index 0816d699bde..59783962a6b 100644
--- a/code/modules/paperwork/photography.dm
+++ b/code/modules/paperwork/photography.dm
@@ -284,15 +284,13 @@ GLOBAL_LIST_INIT(SpookyGhosts, list("ghost","shade","shade2","ghost-narsie","hor
 	res.Blend("#000", ICON_OVERLAY)
 
 	var/atoms[] = list()
-	for(var/turf/the_turf in turfs)
+	var/list/datum/lighting_object/lighting_objects = list()
+	for(var/turf/the_turf as anything in turfs)
 		// Add ourselves to the list of stuff to draw
 		atoms.Add(the_turf)
+		lighting_objects += the_turf.lighting_object
 		// As well as anything that isn't invisible.
-		for(var/atom/A in the_turf)
-			if(istype(A, /atom/movable/lighting_object)) //Add lighting to make image look nice
-				atoms.Add(A)
-				continue
-
+		for(var/atom/A as anything in the_turf)
 			// AI can't see unconcealed runes or cult portals
 			if(A.invisibility == INVISIBILITY_RUNES && see_cult)
 				atoms.Add(A)
@@ -324,11 +322,8 @@ GLOBAL_LIST_INIT(SpookyGhosts, list("ghost","shade","shade2","ghost-narsie","hor
 	// Sort the atoms into their layers
 	var/list/sorted = sort_atoms(atoms)
 	var/center_offset = (size-1)/2 * 32 + 1
-	for(var/i; i <= length(sorted); i++)
+	for(var/i in 1 to length(sorted))
 		var/atom/A = sorted[i]
-		if(istype(A, /atom/movable/lighting_object))
-			continue //Lighting objects render last, need to be above all atoms and turfs displayed
-
 		if(A)
 			var/icon/img = getFlatIcon(A)//build_composite_icon(A)
 			if(istype(A, /obj/item/areaeditor/blueprints/ce))
@@ -363,10 +358,10 @@ GLOBAL_LIST_INIT(SpookyGhosts, list("ghost","shade","shade2","ghost-narsie","hor
 		res.Blend(getFlatIcon(the_turf.loc), blendMode2iconMode(the_turf.blend_mode),xoff,yoff)
 
 	// Render lighting objects to make picture look nice.
-	for(var/atom/movable/lighting_object/light in sorted)
-		var/xoff = (light.x - center.x) * 32 + center_offset
-		var/yoff = (light.y - center.y) * 32 + center_offset
-		res.Blend(getFlatIcon(light), blendMode2iconMode(BLEND_MULTIPLY),  light.pixel_x + xoff, light.pixel_y + yoff)
+	for(var/datum/lighting_object/light as anything in lighting_objects)
+		var/xoff = (light.affected_turf.x - center.x) * 32 + center_offset
+		var/yoff = (light.affected_turf.y - center.y) * 32 + center_offset
+		res.Blend(getFlatIcon(light.current_underlay), blendMode2iconMode(BLEND_MULTIPLY),  xoff, yoff)
 
 	return res
 
diff --git a/code/modules/power/generators/turbine.dm b/code/modules/power/generators/turbine.dm
index fe292686cdc..954fcb61f80 100644
--- a/code/modules/power/generators/turbine.dm
+++ b/code/modules/power/generators/turbine.dm
@@ -267,7 +267,6 @@
 		/mob/camera,
 		/obj/effect,
 		/obj/docking_port,
-		/atom/movable/lighting_object,
 		))
 	if(!compressor_ignored_things[entered.type] && !entered.anchored)
 		to_suck_in += entered
@@ -291,7 +290,6 @@
 	/mob/camera,
 	/obj/effect,
 	/obj/docking_port,
-	/atom/movable/lighting_object,
 	))
 	var/list/act_list = list()
 
diff --git a/code/modules/shuttle/on_move.dm b/code/modules/shuttle/on_move.dm
index 999ae6a8cf1..b89795742f8 100644
--- a/code/modules/shuttle/on_move.dm
+++ b/code/modules/shuttle/on_move.dm
@@ -11,10 +11,6 @@
 	abstract_move(T1)
 	return 1
 
-/atom/movable/lighting_object/onShuttleMove(turf/oldT, turf/T1, rotation, mob/calling_mob)
-	// lighting objects should not be moved from their parent turfs
-	return 0
-
 /obj/effect/landmark/shuttle_import/onShuttleMove()
 	// Used for marking where to preview/load shuttles
 	return 0
diff --git a/code/modules/shuttle/shuttle.dm b/code/modules/shuttle/shuttle.dm
index b3850636ee7..b09294a6d8d 100644
--- a/code/modules/shuttle/shuttle.dm
+++ b/code/modules/shuttle/shuttle.dm
@@ -1122,13 +1122,7 @@
 
 /turf/proc/copyTurf(turf/T)
 	if(T.type != type)
-		var/obj/O
-		if(length(underlays))	//we have underlays, which implies some sort of transparency, so we want to a snapshot of the previous turf as an underlay
-			O = new()
-			O.underlays.Add(T)
 		T.ChangeTurf(type, keep_icon = FALSE)
-		if(length(underlays))
-			T.underlays = O.underlays
 	if(T.icon_state != icon_state)
 		T.icon_state = icon_state
 	if(T.icon != icon)
diff --git a/icons/effects/lighting_object.dmi b/icons/effects/lighting_object.dmi
index 03bfa20b44602eba92aa94883365e6699e9c5fae..d2e503958723fba64ad288e8819ffbcdcb87afc0 100644
GIT binary patch
literal 2092
zcmc(g`#;ltAIHD5cCck=Q-r1_r`3gWm^Q}|x+GRkR}M3mV=Z$?4x>4QmWOgXBqJ%x
z6&KUt#*J)p=pcvWCMI83S-OqXB8s`^dfflR{ln+|{^j-ld|r?D^ZkB&E_=8;E1`Cy
z002;Ob#bK0GhKe{kZ^gNHH*c_6F2#kZ@gn@Tu5vrD?T#%8~`MiUwYYu>N3F{ow53E
zm^KkmpYUp*;XkTUVT!tXyUdGuSDrk{r0T~|mMZq#`y|=b@^*yi`u=ejL$vU`-6|@*
z=ZoE4-2tc0VY7$~r?G;|2b6XaZq#KtNAcAySReh1&OE8jnz(6C8)fd6xtTs&xV~t5
z5OZ$j8{`paiG(%y^aB7Qz}3<IRATu8Z#aLRg2{A!?n?f=$-npK!C2$+-;-rM4C4+v
zZw}~YEDkZOiKJcOD6S_dG&ZhFw*}g6uKw(7Um4q6Rc_oUl>UHdT@W|x%LIuU;a@}F
zGeH7KSR&j(A4W?;zbPDrgp}Ta64H<HU)Lt(p*(^OSbE2wZrd&Z(m&3>TVLr$_o6|~
z-brw>w+}qsdpd3dxB5rxO7J(+u>!F=sD5<$SKv&>Js^<28{km8%)oc+(+VI{sw8C&
zhGgQ`+~RLIBly>?vWF*e9#dM8-j+tkVZOmeZX?di_R#Xia)-r%N*IXV#TG--Hc{Y5
z;QOJUCMn#IQi3+3oY0SY7{NWs83;*40mw{_;&jDy+7hCRvXIxjOzh%b)n7fyZ7u7-
z-Rbuft8-Pc6bH|H9FMs<z&<8J>7q6PY?Dr6jgk1$=-lWll~7s9d%~Bv`T%ZVejo#%
zfAcSw9%P?O)4tmdSofozI4uQ(oBPzUXS<Mdi|chj*Q7X{n|l?9C%)TZON+O%shO)e
zqfM3Ma8NxGK-P8HfaI8!eoYMywK&*44Hp&LqD_P<wz6YtwlsD%rK$s$YLIM{?A3qL
z!z#m5XfS}&fMwlMDLoY8T^W3s4wsB@G^LZuvRgw3+5SNaMq#r=Wz{d9+73qgB!=TG
zvga0qAB(cvsjA>$heAG$G&zuc>5<CL9seSCT7Pk<y0e--6rf+e;p51@|G+0~kQ-Rg
zQIvWrkB%|AqUQ8L=V5NGqPsAdG>d#2xt9sgDo?r~i-s)4G~w4`oUY$)%m1ZT;`NsJ
zz}XRBOejq?K@j_3jg%Q!wWP>;ChRvi%}*!orYdaFg0xwZQ@4b}ZQwSj2E?FBtx7Zd
z?f)5_DD-2IL93ZER+GIO4trjM6(UQ5w+va2PmNnMYDraU0R(5K74;aQ@|+^x?&qa&
zBH`sdq`4uD#@jdK?=t3tcvrH86AH!JP{xb3_6!%Bn%y32AOFVHGIdX!{~dE%iLb`W
zWf9*4&V^IeE+<y|84N15s%mi{`b7I(VEguX{l4PN09C3gm5^Q9(J=B0V))1~d<ZT=
z-K?8>G5jGS)co>stjMfx+CL&9;vw{NzkJx1K$h){X%T|NFo-?HP7g=qq4O7Z1UElu
zZoTh1Ts<yMJ}(dp#o5_07i8z*@fcmS_1)aunOxcjobZ6Db46up#4>F2(ty`%z0kr(
ztqccZ8N$-c!t8AA%l`o#L_Z+sWSYbHIMWPIu6j>xQq%LYrTN3rT0^Z-#K^h?Z)=PF
zmTH!}c!fMP4<Rpo_V=Lb&b#U7q!cmU{dOkf$}>-C8&lP<bE$E}{j?u1KG%hLfBX&O
zLNBgBL}}TZglr*S+zHH*3PT5Q)I90h(Va=`L8p?Kj7`PqUni<3PBqN~#8#_Ta+7vz
zia%UbDpv~~XxBN&Pi%hHfu)v?6|dBp&x7qpXkICy=ZYWKF;4b2d=P^+PAn?jnL!m*
zY@P<52^9>bS#b>?sWnoJvY!;wX!z#E1g_PUiOLn-kMikl02}gNnO?0Bsg7@ahKq`}
zh`Od9-Y7nT|0D3kGL0ngE*v#_qicStjK(W!+jqf9a(`UztR+ZWMWo8s;S>I*sd7!x
zYAy(}mrz~zV<zczs?GE&EXTr`NgHs_9q*<(b}#1UoPd0I`VhJYBiRCJiw0inxVOMi
zNCZv()XfviBHfzsWlJaXhfMCo26~z@mXq10t_;KLB_QxR`IwfiwNcosVi9@m>$-5<
z0f`xjB;$@vMjEO`m6Z7%_vHEUtjL0PuuY@Qc(ous=dyM;w4L0!0S?y79*1_xe!zk-
z(j5hNN9w~y<sAt#?;GzIh4=cT37;bxy0LPp{C+xiRZVqeTV{~LEwfR<u{iJP+OU7a
z^Ix6iSy_aj1fHpf6A13BBi&C0PrKt1z>2kSh@HYM<^9=E6DCZLBJL&c*CPr4)OdX3
z4g`x4hjqin=ejYmmVZIM1~2(n>g*9*hcwRy!2o*5VzEuap$Ujq0I+|coUEhip%n4z
ztfq;DjxuY}PGUz9l+sxUaZeu!yr{wQN&6{8>pYQet4v8wUHHE7Vwkg1+`5s{D=Sv!
z40d8|1ygJO)_6Kz(`y&(dCmH)6au7`9O08n1`*&U%(u-}w%EkBp+APyg{-j!QBd!`
zuWOu9czwQHS*PTy{qiH!Ta$l8F0Z$spFdEk?8_AV$JYkWpWuxCUkfLiJ8iaHv89`6
exe;*ji}C9rbAz$~yAk>K54bwHJ2p7bGyV%Xp49&U

literal 1256
zcmeAS@N?(olHy`uVBq!ia0vp^4j|0I1|(Ny7TyC=4OJl#B`&GO$wiq3C7Jno3=9=>
zg2M`mO22;zF8KKMiI%sn*10q1gExd4Tr__0Nawtd=E(pc$L!IgGahGs&TBLlba@MT
z2Z`p0PMNa9BG{<A3&`ZzX>qwrs5n?LXGhbdMMw5LYC5v$${wMntYD$;O@*34VFh1{
z13|_!F;vgdpWU$dpdkYTi?XMSV@SoVw=)$>L_7uBR+n$KmS*RZIWdQsoiF9wQyGf_
zg<`$u2O7`poO9X|%x+?qj43$Sno_>m-u7?4fBy2cNeueyea=_^UG-}HE6=OyX2zHO
zSp1&c_IP5Ud+c=jBR}2#-CJ#zu{r4In@>_^w_G=C*`1FZ2klQLO?|%VLC8C!!lOS@
zTJj^zSPOjlI1iWyN1Ig!nMb##Nd~81p2@d7d&l<{tM_-;)*memW-x!Ez_cR3Tx8Y~
z(c_GJ?=8HzE&KSM_|;;LKkkU%F<~w6{w8~4M%>1SWqW5GjnTh+ImzyF=sV-Q*-Q}=
z`_J(kwMZAQu<-fRzSGVw`0$>4)_wmb>{{m-`<YXF8N<61^VkjK7CoQMeb!82j~Sm-
z@#DN+JKgsD%R(OS&&%lAJy@sNP`yc-!Q}8)rk1LU<zFtokWpJ>5wYy@`S+gnVzo_b
z4gU-8iyUCSS;)<s_S)oE?X8>%>uOe={&Z*Y>ksmBvzQ{LmcQF#F4@xfNa4#~vp}i0
zDw${8V>7>~dnwO2De!({7FUArJr;(Anzt-$a_>jquaG$ReA4^1s~!fdTE;m2uPjqV
zw`nj#e~LBJirIX<?)73dbCYXVWwR|_U;O#u&PnmtAIIC6v3_vbCL{f5mRo&iv-;eq
z^0!ZxXMN<KH;bu4ZMJE{(hE!S`^r{5t}$5eGxPN0h{L~DY(0K&KHmrPdB8xL9-en=
zzFzCHn&!(t4bmSOT-oAp+g)EMAD4Vr<Ure=8O#bTJIyWZmwj_K{LU|?#8lDA8_b}e
za`<Q3udF+(dw&Zu{yXFy%&<PimSG0ZjS1UZ4qCkE@z35Zv3i%ywbDEFv#vh$-($wQ
zLG!#!{iIh@rOrM6@!5U$^?=_qXRSQ{(9+D8G3TW4^{@QdcNS{DRjR#_u}aQ=V=7ld
zwA{`QD=vNGIP5Mh9~@r#+}`TzqWk;WzgG0*1~cTR^fKHC*pSR8zjfdCvxl|W7uVn0
zx32wlh<~^Jhif7StRv?#Us&(_OSJRfo_SSgg8QXDzqH%wHlLyHcy%y?^``?brzie(
znzQ%n>l!J&)yZ*Jb*?;AEc0P}bINwQUEqSp#U8Jp3%z@JV|v!+TF><}4%fb!#dKq`
zHA{e^X`CYCO7^D$Z>1g<#P4!n_VRa?G~=D4^E4a!H$A$M@a<;MZ|7f+-_2rc`&Y86
zmZ|A*{*M%{g!sJDdJ*~9CFjMy-edh*RVllDV?NgdhrACnnx30{RB^~?-FWTNN4HB~
zHg;XRVt40Aqh^Ei&a!ikV!G|=aaRis_$nUC)q1qOwg9GgmBlwoVsd_6a-TQdMs97$
zJcen7DO?P7D-VBsI_-y6Rt?WVpC0`gdXHDD9}8y;U=U$obs&j~`TJGY&+deVI8VcW
QV9~|k>FVdQ&MBb@0An;l`Tzg`

diff --git a/paradise.dme b/paradise.dme
index 807eebcaaa7..3e10ac344e4 100644
--- a/paradise.dme
+++ b/paradise.dme
@@ -656,6 +656,7 @@
 #include "code\datums\elements\earhealing.dm"
 #include "code\datums\elements\high_value_item.dm"
 #include "code\datums\elements\hostile_machine.dm"
+#include "code\datums\elements\light_blocking.dm"
 #include "code\datums\elements\pet_bonus.dm"
 #include "code\datums\elements\rad_insulation.dm"
 #include "code\datums\elements\relay_attackers.dm"