Datum lighting (#15931)

* Turns lighting objects into a datum, makes all lighting be performed with an underlay. big maptick fix very good! (#58991)

credit to zewaka for the idea of using underlays

turns the lighting object movables that were unnecessary and increased maptick into a datum which then applies and removes an underlay in update(). also applies a lot of general lighting clean ups (mostly using as anything in loops and fixing single letter var names).

multiz is a little different by necessity, now only the bottom turf's lighting matters in the brightness of the top turf unlike master where the bottom turf's lighting object is hidden from the vis_contents of the top turf. there are still some kinks to iron out here though, since currently objects suspended in openspace (like tram platforms) look bad and glass floors look bad too

only thing i have left to do is make multiz work (well)

UPDATE: multiz now appears the same as far as i can tell, its possible there are other situations in which its different but datum mats work and it automatically updates if the turf below changes. now i just need to make the system less finnicky if at all possible (and possibly merge managed_turf_vis_content with managed_overlays maybe?)

new update: its basically equivalent to normal multiz as far as i can tell (visually at least, in the circumstances ive tested so far)

NEW NEW UPDATE: turfs no longer have the VIS_HIDE vis_flag and multiz works without stacking the lighting from the floor below! so this shouldnt have any overt drawbacks to master anymore

1 needless movable per tile is terrible for maptick. this is probably a larger improvement than my emissive blocker change in terms of maptick. im guessing we'd get around 0.6 average maptick per player after this where currently we get 0.85 or so

Edit: according to lemon, sybil reached 0.71 maptick per person when tm'd with this

if this is a big enough improvement i might finally be able to get rid of the Gone discord avatar

* Revert "Turns lighting objects into a datum, makes all lighting be performed with an underlay. big maptick fix very good! (#58991)"

This reverts commit ffbbeb64f4.

* port from another codebase

Co-authored-by: Kylerace <kylerlumpkin1@gmail.com>

code/__HELPERS/radiation.dm

@@ -8,7 +8,6 @@
 		/mob/living/silicon/ai,
 		/obj/effect,
 		/obj/docking_port,
-		/atom/movable/lighting_object,
 		/obj/item/projectile,
 		))
 	var/list/processing_list = list(location)

code/_onclick/hud/plane_master.dm

@@ -26,6 +26,7 @@
 
 /obj/screen/plane_master/openspace/backdrop(mob/mymob)
 	filters = list()
+	filters += filter(type="alpha", render_source = LIGHTING_RENDER_TARGET, flags = MASK_INVERSE)
 	filters += filter(type = "drop_shadow", color = "#04080FAA", size = -10)
 	filters += filter(type = "drop_shadow", color = "#04080FAA", size = -15)
 	filters += filter(type = "drop_shadow", color = "#04080FAA", size = -20)
@@ -148,4 +149,4 @@
 /obj/screen/plane_master/runechat/backdrop(mob/mymob)
 	filters = list()
 	if(istype(mymob) && mymob.client?.prefs?.ambientocclusion)
-		filters += AMBIENT_OCCLUSION
+		filters += AMBIENT_OCCLUSION

code/controllers/subsystem/lighting.dm

@@ -71,7 +71,7 @@ SUBSYSTEM_DEF(lighting)
 		MC_SPLIT_TICK
 
 	for (i in 1 to GLOB.lighting_update_objects.len)
-		var/atom/movable/lighting_object/O = GLOB.lighting_update_objects[i]
+		var/datum/lighting_object/O = GLOB.lighting_update_objects[i]
 
 		if (QDELETED(O))
 			continue
@@ -88,4 +88,4 @@ SUBSYSTEM_DEF(lighting)
 
 /datum/controller/subsystem/lighting/Recover()
 	initialized = SSlighting.initialized
-	..()
+	..()

code/game/turfs/change_turf.dm

@@ -6,7 +6,7 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 
 /turf/proc/empty(turf_type=/turf/open/space, baseturf_type, list/ignore_typecache, flags)
 	// Remove all atoms except observers, landmarks, docking ports
-	var/static/list/ignored_atoms = typecacheof(list(/mob/dead, /obj/effect/landmark, /obj/docking_port, /atom/movable/lighting_object))
+	var/static/list/ignored_atoms = typecacheof(list(/mob/dead, /obj/effect/landmark, /obj/docking_port))
 	var/list/allowed_contents = typecache_filter_list_reverse(GetAllContentsIgnoring(ignore_typecache), ignored_atoms)
 	allowed_contents -= src
 	for(var/i in 1 to allowed_contents.len)
@@ -24,10 +24,11 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 		var/obj/O
 		if(underlays.len)	//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)
+			O.underlays += T
 		T.ChangeTurf(type)
 		if(underlays.len)
-			T.underlays = O.underlays
+			T.underlays.Cut()
+			T.underlays += O.underlays
 	if(T.icon_state != icon_state)
 		T.icon_state = icon_state
 	if(T.icon != icon)
@@ -129,6 +130,8 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 				lighting_build_overlay()
 			else
 				lighting_clear_overlay()
+		else if(lighting_object && !lighting_object.needs_update)
+			lighting_object.update()
 
 		for(var/turf/open/space/S in RANGE_TURFS(1, src)) //RANGE_TURFS is in code\__HELPERS\game.dm
 			S.update_starlight()

code/modules/cargo/centcom_podlauncher.dm

@@ -27,7 +27,7 @@
 //Variables declared to change how items in the launch bay are picked and launched. (Almost) all of these are changed in the ui_act proc
 //Some effect groups are choices, while other are booleans. This is because some effects can stack, while others dont (ex: you can stack explosion and quiet, but you cant stack ordered launch and random launch)
 /datum/centcom_podlauncher
-	var/static/list/ignored_atoms = typecacheof(list(null, /mob/dead, /obj/effect/landmark, /obj/docking_port, /atom/movable/lighting_object, /obj/effect/particle_effect/sparks, /obj/effect/DPtarget, /obj/effect/hallucination/simple/supplypod_selector,  /obj/effect/hallucination/simple/dropoff_location))
+	var/static/list/ignored_atoms = typecacheof(list(null, /mob/dead, /obj/effect/landmark, /obj/docking_port, /obj/effect/particle_effect/sparks, /obj/effect/DPtarget, /obj/effect/hallucination/simple/supplypod_selector,  /obj/effect/hallucination/simple/dropoff_location))
 	var/turf/oldTurf //Keeps track of where the user was at if they use the "teleport to centcom" button, so they can go back
 	var/client/holder //client of whoever is using this datum
 	var/area/centcom/supplypod/loading/bay //What bay we're using to launch shit from.

code/modules/lighting/lighting_object.dm

@@ -1,65 +1,48 @@
-/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
+/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
 
-/atom/movable/lighting_object/Initialize(mapload)
+	///the turf that our light is applied to
+	var/turf/affected_turf
+
+/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
 
-	myturf = loc
-	if (myturf.lighting_object)
-		qdel(myturf.lighting_object, force = TRUE)
-	myturf.lighting_object = src
-	myturf.luminosity = 0
+	current_underlay = mutable_appearance(LIGHTING_ICON, "transparent", source.z, LIGHTING_PLANE, 255, RESET_COLOR | RESET_ALPHA | RESET_TRANSFORM)
 
-	for(var/turf/open/space/S in RANGE_TURFS(1, src)) //RANGE_TURFS is in code\__HELPERS\game.dm
-		S.update_starlight()
+	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!")
+
+	affected_turf.lighting_object = src
+	affected_turf.luminosity = 0
+
+	for(var/turf/open/space/space_tile in RANGE_TURFS(1, affected_turf))
+		space_tile.update_starlight()
 
 	needs_update = TRUE
 	GLOB.lighting_update_objects += src
 
-/atom/movable/lighting_object/Destroy(var/force)
-	if (force)
-		GLOB.lighting_update_objects     -= 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
+	GLOB.lighting_update_objects -= 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?"
@@ -69,10 +52,9 @@
 	// 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/list/corners = affected_turf.corners
 	var/datum/lighting_corner/cr = dummy_lighting_corner
 	var/datum/lighting_corner/cg = dummy_lighting_corner
 	var/datum/lighting_corner/cb = dummy_lighting_corner
@@ -110,15 +92,20 @@
 	#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 = "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 = "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,
@@ -126,29 +113,6 @@
 			00, 00, 00, 01
 		)
 
-	luminosity = set_luminosity
+		affected_turf.underlays += current_underlay
 
-// 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()
-	return
-
-/atom/movable/lighting_object/onTransitZ()
-	return
-
-/atom/movable/lighting_object/wash(clean_types)
-	return
-
-// Override here to prevent things accidentally moving around overlays.
-/atom/movable/lighting_object/forceMove(atom/destination, var/no_tp=FALSE, var/harderforce = FALSE)
-	if(harderforce)
-		. = ..()
+	affected_turf.luminosity = set_luminosity

code/modules/lighting/lighting_setup.dm

@@ -8,6 +8,6 @@
 			if(!IS_DYNAMIC_LIGHTING(T))
 				continue
 
-			new/atom/movable/lighting_object(T)
+			new/datum/lighting_object(T)
 			CHECK_TICK
 		CHECK_TICK

code/modules/lighting/lighting_turf.dm

@@ -5,7 +5,7 @@
 	var/tmp/lighting_corners_initialised = FALSE
 
 	var/tmp/list/datum/light_source/affecting_lights       // List of light sources affecting this turf.
-	var/tmp/atom/movable/lighting_object/lighting_object // Our lighting object.
+	var/tmp/datum/lighting_object/lighting_object // Our lighting object.
 	var/tmp/list/datum/lighting_corner/corners
 	var/tmp/has_opaque_atom = FALSE // Not to be confused with opacity, this will be TRUE if there's any opaque atom on the tile.
 
@@ -41,7 +41,7 @@
 	if (!lighting_corners_initialised)
 		generate_missing_corners()
 
-	new/atom/movable/lighting_object(src)
+	new/datum/lighting_object(src)
 
 	var/thing
 	var/datum/lighting_corner/C
@@ -84,7 +84,7 @@
 	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()

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

@@ -190,7 +190,7 @@
 
 // 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.

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

@@ -51,7 +51,7 @@
 	return ..()
 
 /mob/living/simple_animal/hostile/asteroid/gutlunch/CanAttack(atom/the_target) // Gutlunch-specific version of CanAttack to handle stupid stat_exclusive = true crap so we don't have to do it for literally every single simple_animal/hostile except the two that spawn in lavaland
-	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(see_invisible < the_target.invisibility)//Target's invisible to us, forget it

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

@@ -64,7 +64,7 @@
 	. = ..()
 
 /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

code/modules/mob/mob.dm

@@ -207,7 +207,7 @@
 			msg = blind_message
 		else if(T != loc && T != src) //if src is inside something and not a turf.
 			msg = blind_message
-		else if(T.lighting_object && T.lighting_object.invisibility <= M.see_invisible && T.is_softly_lit()) //if it is too dark.
+		else if(M.lighting_alpha > LIGHTING_PLANE_ALPHA_MOSTLY_INVISIBLE && T.is_softly_lit() && !in_range(T,M)) //if it is too dark.
 			msg = blind_message
 		if(!msg)
 			continue

code/modules/shuttle/on_move.dm

@@ -373,9 +373,6 @@ All ShuttleMove procs go here
 
 /************************************Misc move procs************************************/
 
-/atom/movable/lighting_object/onShuttleMove()
-	return FALSE
-
 /obj/docking_port/mobile/beforeShuttleMove(turf/newT, rotation, move_mode, obj/docking_port/mobile/moving_dock)
 	. = ..()
 	if(moving_dock == src)