Refactored directionals (#20082)

Refactored directionals, ported lists of directions from TG, got rid of
useless proc to get the reverse direction.

code/game/objects/effects/temporary_visuals/blood_splatter.dm

@@ -7,7 +7,7 @@
 	var/splatter_type = "splatter"
 
 /obj/effect/temp_visual/dir_setting/bloodsplatter/Initialize(mapload, set_dir, _color)
-	if(set_dir in GLOB.cornerdirs)
+	if(set_dir in GLOB.diagonals)
 		icon_state = "[splatter_type][pick(1, 2, 6)]"
 	else
 		icon_state = "[splatter_type][pick(3, 4, 5)]"

code/game/objects/effects/temporary_visuals/temporary_visual.dm

@@ -13,7 +13,7 @@
 	if(new_dir)
 		set_dir(new_dir)
 	else if(randomdir)
-		set_dir(pick(GLOB.cardinal))
+		set_dir(pick(GLOB.cardinals))
 
 	QDEL_IN(src, duration)