[SPRITES] Emissive mechs (#26589)

* Emissive mechs

* I accidentally touched the Durand

* old_durand lightmask

* Phazon open sprite upgrade

* Move emissives to seperate file

* Add unique emissives for dragon armour ripleys

* Edge cases for updating overlays

* Changed number to a define

* Added Autodoc

---------

Co-authored-by: adrermail@gmail.com <adrermail@gmail.com>

code/game/mecha/mecha.dm

@@ -4,6 +4,7 @@
 	name = "Mecha"
 	desc = "Exosuit"
 	icon = 'icons/mecha/mecha.dmi'
+
 	density = TRUE //Dense. To raise the heat.
 	opacity = TRUE ///opaque. Menacing.
 	anchored = TRUE //no pulling around.
@@ -37,8 +38,11 @@
 	var/dna	//dna-locking the mech
 	var/list/proc_res = list() //stores proc owners, like proc_res["functionname"] = owner reference
 	var/datum/effect_system/spark_spread/spark_system = new
-	var/lights = 0
+	var/lights = FALSE
 	var/lights_power = 6
+	var/lights_range = 6
+	var/lights_power_ambient = LIGHTING_MINIMUM_POWER
+	var/lights_range_ambient = MINIMUM_USEFUL_LIGHT_RANGE
 	var/frozen = FALSE
 	var/repairing = FALSE
 	var/emp_proof = FALSE //If it is immune to emps
@@ -81,6 +85,9 @@
 	var/activated = FALSE
 	var/power_warned = FALSE
 
+	/// DMI containing greyscale emissive overlays, responsible for what parts of the mech glow in the dark
+	var/emissive_appearance_icon = 'icons/mecha/mecha_emissive.dmi'
+
 	var/destruction_sleep_duration = 2 SECONDS //Time that mech pilot is put to sleep for if mech is destroyed
 
 	var/melee_cooldown = 10
@@ -147,6 +154,14 @@
 	V.install(src)
 	qdel(V)
 
+	set_light(lights_range_ambient, lights_power_ambient)
+	update_overlays()
+
+/obj/mecha/update_overlays()
+	. = ..()
+	underlays.Cut()
+	underlays += emissive_appearance(emissive_appearance_icon, "[icon_state]_lightmask")
+
 ////////////////////////
 ////// Helpers /////////
 ////////////////////////
@@ -1018,6 +1033,7 @@
 	AI.forceMove(src)
 	occupant = AI
 	icon_state = reset_icon(icon_state)
+	update_overlays()
 	playsound(src, 'sound/machines/windowdoor.ogg', 50, 1)
 	if(!hasInternalDamage())
 		SEND_SOUND(occupant, sound(nominalsound, volume = 50))
@@ -1086,9 +1102,9 @@
 /obj/mecha/proc/toggle_lights(show_message = TRUE)
 	lights = !lights
 	if(lights)
-		set_light(light_range + lights_power)
+		set_light(lights_range, lights_power)
 	else
-		set_light(light_range - lights_power)
+		set_light(lights_range_ambient, lights_power_ambient)
 	if(show_message)
 		occupant_message("Toggled lights [lights ? "on" : "off"].")
 		log_message("Toggled lights [lights ? "on" : "off"].")
@@ -1175,6 +1191,7 @@
 			H.throw_alert("locked", /atom/movable/screen/alert/mech_maintenance)
 		if(connected_port)
 			H.throw_alert("mechaport_d", /atom/movable/screen/alert/mech_port_disconnect)
+		update_overlays()
 		return TRUE
 	else
 		return FALSE
@@ -1230,6 +1247,7 @@
 		Move(loc)
 		icon_state = reset_icon()
 		dir = dir_in
+		update_overlays()
 		log_message("[mmi_as_oc] moved in as pilot.")
 		if(!hasInternalDamage())
 			SEND_SOUND(occupant, sound(nominalsound, volume = 50))
@@ -1319,6 +1337,7 @@
 	if(ishuman(L))
 		var/mob/living/carbon/human/H = L
 		H.regenerate_icons() // workaround for 14457
+	update_overlays()
 
 /obj/mecha/force_eject_occupant(mob/target)
 	go_out()

code/game/mecha/mecha_actions.dm

@@ -66,10 +66,10 @@
 		return
 	chassis.lights = !chassis.lights
 	if(chassis.lights)
-		chassis.set_light(chassis.lights_power)
+		chassis.set_light(chassis.lights_range, chassis.lights_power)
 		button_overlay_icon_state = "mech_lights_on"
 	else
-		chassis.set_light(-chassis.lights_power)
+		chassis.set_light(chassis.lights_range_ambient, chassis.lights_power_ambient)
 		button_overlay_icon_state = "mech_lights_off"
 	chassis.occupant_message("Toggled lights [chassis.lights ? "on" : "off"].")
 	chassis.log_message("Toggled lights [chassis.lights ? "on" : "off"].")

code/game/mecha/working/ripley.dm

@@ -123,6 +123,8 @@
 //drake hides
 	if(drake_hides)
 		if(drake_hides == DRAKE_HIDES_COVERED_FULL)
+			underlays.Cut()
+			underlays += emissive_appearance(emissive_appearance_icon, occupant ? "ripley-d-full_lightmask" : "ripley-d-full-open_lightmask")
 			. += occupant ? "ripley-d-full" : "ripley-d-full-open"
 		else if(drake_hides == DRAKE_HIDES_COVERED_MODERATE)
 			. += occupant ? "ripley-d-2" : "ripley-d-2-open"