// Returns the atom sitting on the turf.
// For example, using this on a disk, which is in a bag, on a mob, will return the mob because it's on the turf.
/proc/get_atom_on_turf(var/atom/movable/M)
	var/atom/mloc = M
	while(mloc && mloc.loc && !istype(mloc.loc, /turf/))
		mloc = mloc.loc
	return mloc

/proc/iswall(turf/T)
	return (istype(T, /turf/simulated/wall) || istype(T, /turf/unsimulated/wall) || istype(T, /turf/simulated/shuttle/wall))

/proc/isfloor(turf/T)
	return (istype(T, /turf/simulated/floor) || istype(T, /turf/unsimulated/floor) || istype(T, /turf/simulated/shuttle/floor))

/proc/turf_clear(turf/T)
	for(var/atom/A in T)
		if(A.simulated)
			return 0
	return 1

// Picks a turf without a mob from the given list of turfs, if one exists.
// If no such turf exists, picks any random turf from the given list of turfs.
/proc/pick_mobless_turf_if_exists(var/list/start_turfs)
	if(!start_turfs.len)
		return null

	var/list/available_turfs = list()
	for(var/start_turf in start_turfs)
		var/mob/M = locate() in start_turf
		if(!M)
			available_turfs += start_turf
	if(!available_turfs.len)
		available_turfs = start_turfs
	return pick(available_turfs)

/proc/is_below_sound_pressure(var/turf/T)
	var/datum/gas_mixture/environment = T ? T.return_air() : null
	var/pressure =  environment ? environment.return_pressure() : 0
	if(pressure < SOUND_MINIMUM_PRESSURE)
		return TRUE
	return FALSE