Improve SStitle. No delay icon loading (#25541)

code/controllers/subsystem/mapping.dm

@@ -8,7 +8,6 @@ var/datum/controller/subsystem/mapping/SSmapping
 	var/list/nuke_tiles = list()
 	var/list/nuke_threats = list()
 
-	var/datum/map_config/previous_map_config
 	var/datum/map_config/config
 	var/datum/map_config/next_map_config
 
@@ -23,10 +22,6 @@ var/datum/controller/subsystem/mapping/SSmapping
 
 /datum/controller/subsystem/mapping/New()
 	NEW_SS_GLOBAL(SSmapping)
-	if(!previous_map_config)
-		previous_map_config = new("data/previous_map.json", delete_after = TRUE)
-		if(previous_map_config.defaulted)
-			previous_map_config = null
 	if(!config)
 #ifdef FORCE_MAP
 		config = new(FORCE_MAP)
@@ -97,7 +92,6 @@ var/datum/controller/subsystem/mapping/SSmapping
 	shuttle_templates = SSmapping.shuttle_templates
 	shelter_templates = SSmapping.shelter_templates
 
-	previous_map_config = SSmapping.previous_map_config
 	config = SSmapping.config
 	next_map_config = SSmapping.next_map_config
 
@@ -194,10 +188,6 @@ var/datum/controller/subsystem/mapping/SSmapping
 	next_map_config = VM
 	return TRUE
 
-/datum/controller/subsystem/mapping/Shutdown()
-	if(config)
-		config.MakePreviousMap()
-
 /datum/controller/subsystem/mapping/proc/preloadTemplates(path = "_maps/templates/") //see master controller setup
 	var/list/filelist = flist(path)
 	for(var/map in filelist)

code/controllers/subsystem/title_screen.dm

@@ -2,38 +2,53 @@ var/datum/controller/subsystem/title/SStitle
 
 /datum/controller/subsystem/title
 	name = "Title Screen"
-	init_order = 15
-	flags = SS_NO_FIRE
-	var/turf/closed/indestructible/splashscreen/title_screen
+	flags = SS_NO_FIRE|SS_NO_INIT
+
+	var/file_path
+	var/icon/icon
+	var/icon/previous_icon
+	var/turf/closed/indestructible/splashscreen/splash_turf
 
 /datum/controller/subsystem/title/New()
 	NEW_SS_GLOBAL(SStitle)
 
-/datum/controller/subsystem/title/Initialize()
+	if(file_path && icon)
+		return
+
+	if(fexists("data/previous_title.dat"))
+		previous_icon = new("data/previous_title.dat")
+		fdel("data/previous_title.dat")	//linger not
+
 	var/list/provisional_title_screens = flist("config/title_screens/images/")
 	var/list/title_screens = list()
-	var/use_rare_screens = FALSE
+	var/use_rare_screens = prob(1)
 
-	if(title_screen)
-		if(prob(1))
-			use_rare_screens = TRUE
+	for(var/S in provisional_title_screens)
+		var/list/L = splittext(S,"+")
+		if((L.len == 1 && L[1] != "blank.png")|| (L.len > 1 && ((use_rare_screens && lowertext(L[1]) == "rare") || (lowertext(L[1]) == lowertext(SSmapping.config.map_name)))))
+			title_screens += S
 
-		for(var/S in provisional_title_screens)
-			var/list/L = splittext(S,"+")
-			if((L.len == 1 && L[1] != "blank.png")|| (L.len > 1 && ((use_rare_screens && lowertext(L[1]) == "rare") || (lowertext(L[1]) == lowertext(SSmapping.config.map_name)))))
-				title_screens += S
+	if(!isemptylist(title_screens))
+		if(length(title_screens) > 1)
+			for(var/S in title_screens)
+				var/list/L = splittext(S,".")
+				if(L.len != 2 || L[1] != "default")
+					continue
+				title_screens -= S
+				break
 
-		if(!isemptylist(title_screens))
-			if(length(title_screens) > 1)
-				for(var/S in title_screens)
-					var/list/L = splittext(S,".")
-					if(L.len != 2 || L[1] != "default")
-						continue
-					title_screens -= S
-					break
+		file_path = "config/title_screens/images/[pick(title_screens)]"
+		icon = new(file_path)
 
-			var/path_string = "config/title_screens/images/[pick(title_screens)]"
-			var/icon/screen_to_use = new(path_string)
+		if(splash_turf)
+			splash_turf.icon = icon
 
-			title_screen.icon = screen_to_use
-	..()
+/datum/controller/subsystem/title/Shutdown()
+	if(file_path)
+		fcopy(file_path, "data/previous_title.dat")
+
+/datum/controller/subsystem/title/Recover()
+	icon = SStitle.icon
+	splash_turf = SStitle.splash_turf
+	file_path = SStitle.file_path
+	previous_icon = SStitle.previous_icon