Optimize get_hearers_in_view() (#421)

* swap out view() for hearers()

* docs

code/__HELPERS/spatial_info.dm

@@ -104,23 +104,17 @@
 
 	var/list/assigned_oranges_ears = SSspatial_grid.assign_oranges_ears(hearables_from_grid)
 
-	var/old_luminosity = center_turf.luminosity
-	center_turf.luminosity = 6 //man if only we had an inbuilt dview()
-
 	//this is the ENTIRE reason all this shit is worth it due to how view() works and can be optimized
 	//view() constructs lists of viewed atoms by default and specifying a specific type of atom to look for limits the lists it constructs to those of that
 	//primitive type and then when the view operation is completed the output is then typechecked to only iterate through objects in view with the same
-	//typepath. by assigning one /mob/oranges_ear to every turf with hearable atoms on it and giving them references to each one means that:
-	//1. view() only constructs lists of atoms with the mob primitive type and
-	//2. the mobs returned by view are fast typechecked to only iterate through /mob/oranges_ear mobs, which guarantees at most one per turf
-	//on a whole this can outperform iterating through all movables in view() by ~2x especially when hearables are a tiny percentage of movables in view
-	for(var/mob/oranges_ear/ear in view(view_radius, center_turf))
+	//typepath. by assigning one /mob/oranges_ear to every turf with hearable atoms on it and giving them references to each one means that
+	//hearers() can be used over view(), which is a huge speed increase.
+	for(var/mob/oranges_ear/ear in hearers(view_radius, center_turf))
 		. += ear.references
 
 	for(var/mob/oranges_ear/remaining_ear as anything in assigned_oranges_ears)//we need to clean up our mess
 		remaining_ear.unassign()
 
-	center_turf.luminosity = old_luminosity
 	return .
 
 /**