[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/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)