Merge pull request #12217 from Putnam3145/putnamos-for-real

The real fastmos: C++ monstermos port

code/__DEFINES/atmospherics.dm

@@ -136,7 +136,7 @@
 #define TANK_FRAGMENT_SCALE	    			(6.*ONE_ATMOSPHERE)		//+1 for each SCALE kPa aboe threshold
 #define TANK_MAX_RELEASE_PRESSURE 			(ONE_ATMOSPHERE*3)
 #define TANK_MIN_RELEASE_PRESSURE 			0
-#define TANK_DEFAULT_RELEASE_PRESSURE 		16
+#define TANK_DEFAULT_RELEASE_PRESSURE 		17
 
 //CANATMOSPASS
 #define ATMOS_PASS_YES 1
@@ -270,16 +270,9 @@
 	T.pixel_x = (PipingLayer - PIPING_LAYER_DEFAULT) * PIPING_LAYER_P_X;\
 	T.pixel_y = (PipingLayer - PIPING_LAYER_DEFAULT) * PIPING_LAYER_P_Y;
 
-#define THERMAL_ENERGY(gas) (gas.temperature * gas.heat_capacity())
 #define QUANTIZE(variable)		(round(variable,0.0000001))/*I feel the need to document what happens here. Basically this is used to catch most rounding errors, however it's previous value made it so that
 															once gases got hot enough, most procedures wouldnt occur due to the fact that the mole counts would get rounded away. Thus, we lowered it a few orders of magnititude */
 
-//prefer this to gas_mixture/total_moles in performance critical areas
-#define TOTAL_MOLES(cached_gases, out_var)\
-	out_var = 0;\
-	for(var/total_moles_id in cached_gases){\
-		out_var += cached_gases[total_moles_id];\
-	}
 
 #ifdef TESTING
 GLOBAL_LIST_INIT(atmos_adjacent_savings, list(0,0))
@@ -288,6 +281,19 @@ GLOBAL_LIST_INIT(atmos_adjacent_savings, list(0,0))
 #define CALCULATE_ADJACENT_TURFS(T) SSadjacent_air.queue[T] = 1
 #endif
 
+#define EXTOOLS (world.system_type == MS_WINDOWS ? "byond-extools.dll" : "libbyond-extools.so")
+
+GLOBAL_VAR(atmos_extools_initialized) // this must be an uninitialized (null) one or init_monstermos will be called twice because reasons
+#define ATMOS_EXTOOLS_CHECK if(!GLOB.atmos_extools_initialized){\
+	GLOB.atmos_extools_initialized=TRUE;\
+	if(fexists(EXTOOLS)){\
+		var/result = call(EXTOOLS,"init_monstermos")();\
+		if(result != "ok") {CRASH(result);}\
+	} else {\
+		CRASH("[EXTOOLS] does not exist!");\
+	}\
+}
+
 //Unomos - So for whatever reason, garbage collection actually drastically decreases the cost of atmos later in the round. Turning this into a define yields massively improved performance.
 #define GAS_GARBAGE_COLLECT(GASGASGAS)\
 	var/list/CACHE_GAS = GASGASGAS;\
@@ -296,10 +302,6 @@ GLOBAL_LIST_INIT(atmos_adjacent_savings, list(0,0))
 			CACHE_GAS -= id;\
 	}
 
-#define ARCHIVE_TEMPERATURE(gas) gas.temperature_archived = gas.temperature
-
-#define ARCHIVE(gas) gas.temperature_archived = gas.temperature; gas.gas_archive = gas.gases.Copy();
-
 GLOBAL_LIST_INIT(pipe_paint_colors, list(
 		"amethyst" = rgb(130,43,255), //supplymain
 		"blue" = rgb(0,0,255),

code/__DEFINES/spaceman_dmm.dm

@@ -29,6 +29,5 @@
 #endif
 
 /world/proc/enable_debugger()
-    var/dll = world.GetConfig("env", "EXTOOLS_DLL")
+    if (fexists(EXTOOLS))
-    if (dll)
+        call(EXTOOLS, "debug_initialize")()
-        call(dll, "debug_initialize")()

code/__DEFINES/subsystems.dm

@@ -137,12 +137,13 @@
 // SSair run section
 #define SSAIR_PIPENETS 1
 #define SSAIR_ATMOSMACHINERY 2
-#define SSAIR_REACTQUEUE 3
+#define SSAIR_EXCITEDGROUPS 3
-#define SSAIR_EXCITEDGROUPS 4
+#define SSAIR_HIGHPRESSURE 4
-#define SSAIR_HIGHPRESSURE 5
+#define SSAIR_HOTSPOTS 5
-#define SSAIR_HOTSPOTS 6
+#define SSAIR_SUPERCONDUCTIVITY 6
-#define SSAIR_SUPERCONDUCTIVITY 7
+#define SSAIR_REBUILD_PIPENETS 7
-#define SSAIR_REBUILD_PIPENETS 8
+#define SSAIR_EQUALIZE 8
+#define SSAIR_ACTIVETURFS 9
 
 #define COMPILE_OVERLAYS(A)\
 	if (TRUE) {\

code/controllers/subsystem/air.dm

@@ -6,7 +6,7 @@ SUBSYSTEM_DEF(air)
 	flags = SS_BACKGROUND
 	runlevels = RUNLEVEL_GAME | RUNLEVEL_POSTGAME
 
-	var/cost_turf_reactions = 0
+	var/cost_turfs = 0
 	var/cost_groups = 0
 	var/cost_highpressure = 0
 	var/cost_hotspots = 0
@@ -14,10 +14,9 @@ SUBSYSTEM_DEF(air)
 	var/cost_pipenets = 0
 	var/cost_rebuilds = 0
 	var/cost_atmos_machinery = 0
+	var/cost_equalize = 0
 
-	var/list/excited_groups = list()
 	var/list/active_turfs = list()
-	var/list/turf_react_queue = list()
 	var/list/hotspots = list()
 	var/list/networks = list()
 	var/list/pipenets_needing_rebuilt = list()
@@ -38,20 +37,25 @@ SUBSYSTEM_DEF(air)
 	var/map_loading = TRUE
 	var/list/queued_for_activation
 
+	var/log_explosive_decompression = TRUE // If things get spammy, admemes can turn this off.
+
+	var/monstermos_turf_limit = 10
+	var/monstermos_hard_turf_limit = 2000
+	var/monstermos_enabled = TRUE
+
 /datum/controller/subsystem/air/stat_entry(msg)
 	msg += "C:{"
-	msg += "RQ:[round(cost_turf_reactions,1)]|"
+	msg += "EQ:[round(cost_equalize,1)]|"
+	msg += "AT:[round(cost_turfs,1)]|"
 	msg += "EG:[round(cost_groups,1)]|"
 	msg += "HP:[round(cost_highpressure,1)]|"
 	msg += "HS:[round(cost_hotspots,1)]|"
 	msg += "SC:[round(cost_superconductivity,1)]|"
 	msg += "PN:[round(cost_pipenets,1)]|"
-	msg += "RB:[round(cost_rebuilds,1)]|"
 	msg += "AM:[round(cost_atmos_machinery,1)]"
 	msg += "} "
 	msg += "AT:[active_turfs.len]|"
-	msg += "RQ:[turf_react_queue.len]|"
+	msg += "EG:[get_amt_excited_groups()]|"
-	msg += "EG:[excited_groups.len]|"
 	msg += "HS:[hotspots.len]|"
 	msg += "PN:[networks.len]|"
 	msg += "HP:[high_pressure_delta.len]|"
@@ -59,8 +63,8 @@ SUBSYSTEM_DEF(air)
 	msg += "AT/MS:[round((cost ? active_turfs.len/cost : 0),0.1)]"
 	..(msg)
 
-
 /datum/controller/subsystem/air/Initialize(timeofday)
+	extools_update_ssair()
 	map_loading = FALSE
 	setup_allturfs()
 	setup_atmos_machinery()
@@ -68,6 +72,7 @@ SUBSYSTEM_DEF(air)
 	gas_reactions = init_gas_reactions()
 	return ..()
 
+/datum/controller/subsystem/air/proc/extools_update_ssair()
 
 /datum/controller/subsystem/air/fire(resumed = 0)
 	var/timer = TICK_USAGE_REAL
@@ -101,12 +106,21 @@ SUBSYSTEM_DEF(air)
 		if(state != SS_RUNNING)
 			return
 		resumed = 0
-		currentpart = SSAIR_REACTQUEUE
+		currentpart = monstermos_enabled ? SSAIR_EQUALIZE : SSAIR_ACTIVETURFS
 
-	if(currentpart == SSAIR_REACTQUEUE)
+	if(currentpart == SSAIR_EQUALIZE)
 		timer = TICK_USAGE_REAL
-		process_react_queue(resumed)
+		process_turf_equalize(resumed)
-		cost_turf_reactions = MC_AVERAGE(cost_turf_reactions, TICK_DELTA_TO_MS(TICK_USAGE_REAL - timer))
+		cost_equalize = MC_AVERAGE(cost_equalize, TICK_DELTA_TO_MS(TICK_USAGE_REAL - timer))
+		if(state != SS_RUNNING)
+			return
+		resumed = 0
+		currentpart = SSAIR_ACTIVETURFS
+
+	if(currentpart == SSAIR_ACTIVETURFS)
+		timer = TICK_USAGE_REAL
+		process_active_turfs(resumed)
+		cost_turfs = MC_AVERAGE(cost_turfs, TICK_DELTA_TO_MS(TICK_USAGE_REAL - timer))
 		if(state != SS_RUNNING)
 			return
 		resumed = 0
@@ -148,6 +162,8 @@ SUBSYSTEM_DEF(air)
 		resumed = 0
 	currentpart = SSAIR_REBUILD_PIPENETS
 
+
+
 /datum/controller/subsystem/air/proc/process_pipenets(resumed = 0)
 	if (!resumed)
 		src.currentrun = networks.Copy()
@@ -182,19 +198,6 @@ SUBSYSTEM_DEF(air)
 			return
 
 
-/datum/controller/subsystem/air/proc/process_react_queue(resumed = 0)
-	if(!resumed)
-		src.currentrun = turf_react_queue.Copy()
-	var/list/currentrun = src.currentrun
-	while(currentrun.len)
-		var/turf/open/T = currentrun[currentrun.len]
-		currentrun.len--
-		if(T)
-			T.process_cell_reaction()
-		if(MC_TICK_CHECK)
-			return
-
-
 /datum/controller/subsystem/air/proc/process_super_conductivity(resumed = 0)
 	if (!resumed)
 		src.currentrun = active_super_conductivity.Copy()
@@ -229,10 +232,45 @@ SUBSYSTEM_DEF(air)
 		high_pressure_delta.len--
 		T.high_pressure_movements()
 		T.pressure_difference = 0
+		T.pressure_specific_target = null
 		if(MC_TICK_CHECK)
 			return
 
+/datum/controller/subsystem/air/proc/process_turf_equalize(resumed = 0)
+	//cache for sanic speed
+	var/fire_count = times_fired
+	if (!resumed)
+		src.currentrun = active_turfs.Copy()
+	//cache for sanic speed (lists are references anyways)
+	var/list/currentrun = src.currentrun
+	while(currentrun.len)
+		var/turf/open/T = currentrun[currentrun.len]
+		currentrun.len--
+		if (T)
+			T.equalize_pressure_in_zone(fire_count)
+			//equalize_pressure_in_zone(T, fire_count)
+		if (MC_TICK_CHECK)
+			return
+
+/datum/controller/subsystem/air/proc/process_active_turfs(resumed = 0)
+	//cache for sanic speed
+	var/fire_count = times_fired
+	if (!resumed)
+		src.currentrun = active_turfs.Copy()
+	//cache for sanic speed (lists are references anyways)
+	var/list/currentrun = src.currentrun
+	while(currentrun.len)
+		var/turf/open/T = currentrun[currentrun.len]
+		currentrun.len--
+		if (T)
+			T.process_cell(fire_count)
+		if (MC_TICK_CHECK)
+			return
+
 /datum/controller/subsystem/air/proc/process_excited_groups(resumed = 0)
+	if(process_excited_groups_extools(resumed, (Master.current_ticklimit - TICK_USAGE) * 0.01 * world.tick_lag))
+		sleep()
+	/*
 	if (!resumed)
 		src.currentrun = excited_groups.Copy()
 	//cache for sanic speed (lists are references anyways)
@@ -248,29 +286,33 @@ SUBSYSTEM_DEF(air)
 			EG.dismantle()
 		if (MC_TICK_CHECK)
 			return
+	*/
+
+/datum/controller/subsystem/air/proc/process_excited_groups_extools()
+/datum/controller/subsystem/air/proc/get_amt_excited_groups()
 
 /datum/controller/subsystem/air/proc/remove_from_active(turf/open/T)
 	active_turfs -= T
-	SSair_turfs.currentrun -= T
+	if(currentpart == SSAIR_ACTIVETURFS)
+		currentrun -= T
 	#ifdef VISUALIZE_ACTIVE_TURFS
 	T.remove_atom_colour(TEMPORARY_COLOUR_PRIORITY, "#00ff00")
 	#endif
 	if(istype(T))
-		T.excited = 0
+		T.set_excited(FALSE)
-		if(T.excited_group)
+		T.eg_garbage_collect()
-			T.excited_group.garbage_collect()
-	remove_from_react_queue(T)
 
 /datum/controller/subsystem/air/proc/add_to_active(turf/open/T, blockchanges = 1)
 	if(istype(T) && T.air)
 		#ifdef VISUALIZE_ACTIVE_TURFS
 		T.add_atom_colour("#00ff00", TEMPORARY_COLOUR_PRIORITY)
 		#endif
-		T.excited = TRUE
+		T.set_excited(TRUE)
-		active_turfs[T] = SSair_turfs.currentrun[T] = TRUE
+		active_turfs |= T
-		if(blockchanges && T.excited_group)
+		if(currentpart == SSAIR_ACTIVETURFS)
-			T.excited_group.garbage_collect()
+			currentrun |= T
-		add_to_react_queue(T)
+		if(blockchanges)
+			T.eg_garbage_collect()
 	else if(T.flags_1 & INITIALIZED_1)
 		for(var/turf/S in T.atmos_adjacent_turfs)
 			add_to_active(S)
@@ -281,17 +323,6 @@ SUBSYSTEM_DEF(air)
 	else
 		T.requires_activation = TRUE
 
-/datum/controller/subsystem/air/proc/add_to_react_queue(turf/open/T)
-	if(istype(T) && T.air)
-		turf_react_queue[T] = TRUE
-		if(currentpart == SSAIR_REACTQUEUE)
-			currentrun[T] = TRUE
-
-/datum/controller/subsystem/air/proc/remove_from_react_queue(turf/open/T)
-	turf_react_queue -= T
-	if(currentpart == SSAIR_REACTQUEUE)
-		currentrun -= T
-
 /datum/controller/subsystem/air/StartLoadingMap()
 	LAZYINITLIST(queued_for_activation)
 	map_loading = TRUE
@@ -339,11 +370,11 @@ SUBSYSTEM_DEF(air)
 
 		while (turfs_to_check.len)
 		var/ending_ats = active_turfs.len
-		for(var/thing in excited_groups)
+		/*for(var/thing in excited_groups)
 			var/datum/excited_group/EG = thing
-			EG.self_breakdown(space_is_all_consuming = 1)
+			//EG.self_breakdown(space_is_all_consuming = 1)
-			EG.dismantle()
+			//EG.dismantle()
-			CHECK_TICK
+			CHECK_TICK*/
 
 		var/msg = "HEY! LISTEN! [DisplayTimeText(world.timeofday - timer)] were wasted processing [starting_ats] turf(s) (connected to [ending_ats] other turfs) with atmos differences at round start."
 		to_chat(world, "<span class='boldannounce'>[msg]</span>")
@@ -351,6 +382,7 @@ SUBSYSTEM_DEF(air)
 
 /turf/open/proc/resolve_active_graph()
 	. = list()
+	/*
 	var/datum/excited_group/EG = excited_group
 	if (blocks_air || !air)
 		return
@@ -371,7 +403,8 @@ SUBSYSTEM_DEF(air)
 			EG.add_turf(ET)
 		if (!ET.excited)
 			ET.excited = 1
-			. += ET
+			. += ET*/
+
 /turf/open/space/resolve_active_graph()
 	return list()
 
@@ -389,9 +422,8 @@ SUBSYSTEM_DEF(air)
 		CHECK_TICK
 
 /datum/controller/subsystem/air/proc/setup_template_machinery(list/atmos_machines)
-	if(!initialized)
+	if(!initialized) // yogs - fixes randomized bars
-		return
+		return // yogs
-
 	for(var/A in atmos_machines)
 		var/obj/machinery/atmospherics/AM = A
 		AM.atmosinit()
@@ -415,6 +447,7 @@ SUBSYSTEM_DEF(air)
 
 #undef SSAIR_PIPENETS
 #undef SSAIR_ATMOSMACHINERY
+#undef SSAIR_ACTIVETURFS
 #undef SSAIR_EXCITEDGROUPS
 #undef SSAIR_HIGHPRESSURE
 #undef SSAIR_HOTSPOTS

code/controllers/subsystem/air_turfs.dm

@@ -1,5 +1,5 @@
 //WHAT IF WE TAKE THE ACTIVE TURF PROCESSING AND PUSH IT SOMEWHERE ELSE!!!
-
+/*
 SUBSYSTEM_DEF(air_turfs)
 	name = "Atmospherics - Turfs"
 	init_order = INIT_ORDER_AIR_TURFS
@@ -24,3 +24,4 @@ SUBSYSTEM_DEF(air_turfs)
 			return
 	resumed = 0
 	return
+*/

code/datums/components/wet_floor.dm

@@ -121,7 +121,7 @@
 		if(-INFINITY to T0C)
 			add_wet(TURF_WET_ICE, max_time_left())			//Water freezes into ice!
 		if(T0C to T0C + 100)
-			decrease = ((T.air.temperature - T0C) / SSwet_floors.temperature_coeff) * (diff / SSwet_floors.time_ratio)
+			decrease = ((T.air.return_temperature() - T0C) / SSwet_floors.temperature_coeff) * (diff / SSwet_floors.time_ratio)
 		if(T0C + 100 to INFINITY)
 			decrease = INFINITY
 	decrease = max(0, decrease)

code/datums/diseases/advance/symptoms/heal.dm

@@ -404,7 +404,7 @@
 	if(M.loc)
 		environment = M.loc.return_air()
 	if(environment)
-		plasmamount = environment.gases[/datum/gas/plasma]
+		plasmamount = environment.get_moles(/datum/gas/plasma)
 		if(plasmamount && plasmamount > GLOB.meta_gas_visibility[/datum/gas/plasma]) //if there's enough plasma in the air to see
 			. += power * 0.5
 	if(M.reagents.has_reagent(/datum/reagent/toxin/plasma))

code/datums/helper_datums/teleport.dm

@@ -117,9 +117,8 @@
 			continue
 
 		var/datum/gas_mixture/A = F.air
-		var/list/A_gases = A.gases
 		var/trace_gases
-		for(var/id in A_gases)
+		for(var/id in A.get_gases())
 			if(id in GLOB.hardcoded_gases)
 				continue
 			trace_gases = TRUE
@@ -128,15 +127,15 @@
 		// Can most things breathe?
 		if(trace_gases)
 			continue
-		if(A_gases[/datum/gas/oxygen] <= 16)
+		if(A.get_moles(/datum/gas/oxygen) < 16)
 			continue
-		if(A_gases[/datum/gas/plasma])
+		if(A.get_moles(/datum/gas/plasma))
 			continue
-		if(A_gases[/datum/gas/carbon_dioxide] >= 10)
+		if(A.get_moles(/datum/gas/carbon_dioxide) >= 10)
 			continue
 
 		// Aim for goldilocks temperatures and pressure
-		if((A.temperature <= 270) || (A.temperature >= 360))
+		if((A.return_temperature() <= 270) || (A.return_temperature() >= 360))
 			continue
 		var/pressure = A.return_pressure()
 		if((pressure <= 20) || (pressure >= 550))

code/datums/mutations/actions.dm

@@ -226,9 +226,8 @@
 /obj/effect/proc_holder/spell/targeted/olfaction/cast(list/targets, mob/living/user = usr)
 	//can we sniff? is there miasma in the air?
 	var/datum/gas_mixture/air = user.loc.return_air()
-	var/list/cached_gases = air.gases
 
-	if(cached_gases[/datum/gas/miasma])
+	if(air.get_moles(/datum/gas/miasma))
 		user.adjust_disgust(sensitivity * 45)
 		to_chat(user, "<span class='warning'>With your overly sensitive nose, you get a whiff of stench and feel sick! Try moving to a cleaner area!</span>")
 		return

code/game/gamemodes/objective_items.dm

@@ -125,7 +125,7 @@
 /datum/objective_item/steal/plasma/check_special_completion(obj/item/tank/T)
 	var/target_amount = text2num(name)
 	var/found_amount = 0
-	found_amount += T.air_contents.gases[/datum/gas/plasma]
+	found_amount += T.air_contents.get_moles(/datum/gas/plasma)
 	return found_amount>=target_amount
 
 

code/game/machinery/computer/atmos_control.dm

@@ -53,14 +53,14 @@
 			"id_tag" = id_tag,
 			"timestamp" = world.time,
 			"pressure" = air_sample.return_pressure(),
-			"temperature" = air_sample.temperature,
+			"temperature" = air_sample.return_temperature(),
 			"gases" = list()
 		))
 		var/total_moles = air_sample.total_moles()
 		if(total_moles)
-			for(var/gas_id in air_sample.gases)
+			for(var/gas_id in air_sample.get_gases())
 				var/gas_name = GLOB.meta_gas_names[gas_id]
-				signal.data["gases"][gas_name] = air_sample.gases[gas_id] / total_moles * 100
+				signal.data["gases"][gas_name] = air_sample.get_moles(gas_id) / total_moles * 100
 
 		radio_connection.post_signal(src, signal, filter = RADIO_ATMOSIA)
 

code/game/machinery/doors/airlock.dm

@@ -93,7 +93,7 @@
 	var/shuttledocked = 0
 	var/delayed_close_requested = FALSE // TRUE means the door will automatically close the next time it's opened.
 
-	var/air_tight = FALSE	//TRUE means density will be set as soon as the door begins to close
+	air_tight = FALSE
 	var/prying_so_hard = FALSE
 
 	rad_flags = RAD_PROTECT_CONTENTS | RAD_NO_CONTAMINATE

code/game/machinery/doors/door.dm

@@ -17,6 +17,7 @@
 	interaction_flags_atom = INTERACT_ATOM_UI_INTERACT
 
 	var/secondsElectrified = 0
+	var/air_tight = FALSE	//TRUE means density will be set as soon as the door begins to close
 	var/shockedby
 	var/visible = TRUE // To explain: Whether the door can block line of sight when closed or not.
 	var/operating = FALSE
@@ -161,7 +162,7 @@
 			open()
 		else
 			close()
-		return
+		return TRUE
 	if(density)
 		do_animate("deny")
 
@@ -181,11 +182,36 @@
 /obj/machinery/door/proc/try_to_crowbar(obj/item/I, mob/user)
 	return
 
+/obj/machinery/door/proc/is_holding_pressure()
+	var/turf/open/T = loc
+	if(!T)
+		return FALSE
+	if(!density)
+		return FALSE
+	// alrighty now we check for how much pressure we're holding back
+	var/min_moles = T.air.total_moles()
+	var/max_moles = min_moles
+	// okay this is a bit hacky. First, we set density to 0 and recalculate our adjacent turfs
+	density = FALSE
+	T.ImmediateCalculateAdjacentTurfs()
+	// then we use those adjacent turfs to figure out what the difference between the lowest and highest pressures we'd be holding is
+	for(var/turf/open/T2 in T.atmos_adjacent_turfs)
+		if((flags_1 & ON_BORDER_1) && get_dir(src, T2) != dir)
+			continue
+		var/moles = T2.air.total_moles()
+		if(moles < min_moles)
+			min_moles = moles
+		if(moles > max_moles)
+			max_moles = moles
+	density = TRUE
+	T.ImmediateCalculateAdjacentTurfs() // alright lets put it back
+	return max_moles - min_moles > 20
+
 /obj/machinery/door/attackby(obj/item/I, mob/user, params)
-	if(user.a_intent != INTENT_HARM && (istype(I, /obj/item/crowbar) || istype(I, /obj/item/fireaxe)))
+	if(user.a_intent != INTENT_HARM && (I.tool_behaviour == TOOL_CROWBAR || istype(I, /obj/item/fireaxe)))
 		try_to_crowbar(I, user)
 		return 1
-	else if(istype(I, /obj/item/weldingtool))
+	else if(I.tool_behaviour == TOOL_WELDER)
 		try_to_weld(I, user)
 		return 1
 	else if(!(I.item_flags & NOBLUDGEON) && user.a_intent != INTENT_HARM)
@@ -223,13 +249,13 @@
 	if(prob(20/severity) && (istype(src, /obj/machinery/door/airlock) || istype(src, /obj/machinery/door/window)) )
 		INVOKE_ASYNC(src, .proc/open)
 	if(prob(severity*10 - 20))
-		if(secondsElectrified == 0)
+		if(secondsElectrified == MACHINE_NOT_ELECTRIFIED)
-			secondsElectrified = -1
+			secondsElectrified = MACHINE_ELECTRIFIED_PERMANENT
 			LAZYADD(shockedby, "\[[TIME_STAMP("hh:mm:ss", FALSE)]\]EM Pulse")
 			addtimer(CALLBACK(src, .proc/unelectrify), 300)
 
 /obj/machinery/door/proc/unelectrify()
-	secondsElectrified = 0
+	secondsElectrified = MACHINE_NOT_ELECTRIFIED
 
 /obj/machinery/door/update_icon_state()
 	if(density)
@@ -289,8 +315,11 @@
 				return
 
 	operating = TRUE
+
 	do_animate("closing")
 	layer = closingLayer
+	if(air_tight)
+		density = TRUE
 	sleep(5)
 	density = TRUE
 	sleep(5)
@@ -302,7 +331,7 @@
 	update_freelook_sight()
 	if(safe)
 		CheckForMobs()
-	else
+	else if(!(flags_1 & ON_BORDER_1))
 		crush()
 	return 1
 

code/game/machinery/doors/firedoor.dm

@@ -23,6 +23,8 @@
 	assemblytype = /obj/structure/firelock_frame
 	armor = list("melee" = 30, "bullet" = 30, "laser" = 20, "energy" = 20, "bomb" = 10, "bio" = 100, "rad" = 100, "fire" = 95, "acid" = 70)
 	interaction_flags_machine = INTERACT_MACHINE_WIRES_IF_OPEN | INTERACT_MACHINE_ALLOW_SILICON | INTERACT_MACHINE_OPEN_SILICON | INTERACT_MACHINE_REQUIRES_SILICON | INTERACT_MACHINE_OPEN
+	air_tight = TRUE
+	var/emergency_close_timer = 0
 	var/nextstate = null
 	var/boltslocked = TRUE
 	var/list/affecting_areas
@@ -68,10 +70,14 @@
 	return ..()
 
 /obj/machinery/door/firedoor/Bumped(atom/movable/AM)
-	if(panel_open || operating)
+	if(panel_open || operating || welded)
 		return
-	if(!density)
+	if(ismob(AM))
-		return ..()
+		var/mob/user = AM
+		if(density && !welded && !operating && !(stat & NOPOWER) && (!density || allow_hand_open(user)))
+			add_fingerprint(user)
+			open()
+			return TRUE
 	return FALSE
 
 
@@ -86,6 +92,15 @@
 	. = ..()
 	if(.)
 		return
+
+	if(!welded && !operating && !(stat & NOPOWER) && (!density || allow_hand_open(user)))
+		add_fingerprint(user)
+		if(density)
+			emergency_close_timer = world.time + 30 // prevent it from instaclosing again if in space
+			open()
+		else
+			close()
+		return TRUE
 	if(operating || !density)
 		return
 	user.changeNext_move(CLICK_CD_MELEE)
@@ -100,7 +115,7 @@
 		return
 
 	if(welded)
-		if(istype(C, /obj/item/wrench))
+		if(C.tool_behaviour == TOOL_WRENCH)
 			if(boltslocked)
 				to_chat(user, "<span class='notice'>There are screws locking the bolts in place!</span>")
 				return
@@ -114,7 +129,7 @@
 								 "<span class='notice'>You undo [src]'s floor bolts.</span>")
 			deconstruct(TRUE)
 			return
-		if(istype(C, /obj/item/screwdriver))
+		if(C.tool_behaviour == TOOL_SCREWDRIVER)
 			user.visible_message("<span class='notice'>[user] [boltslocked ? "unlocks" : "locks"] [src]'s bolts.</span>", \
 								 "<span class='notice'>You [boltslocked ? "unlock" : "lock"] [src]'s floor bolts.</span>")
 			C.play_tool_sound(src)
@@ -140,10 +155,27 @@
 		return
 
 	if(density)
+		if(is_holding_pressure())
+			// tell the user that this is a bad idea, and have a do_after as well
+			to_chat(user, "<span class='warning'>As you begin crowbarring \the [src] a gush of air blows in your face... maybe you should reconsider?</span>")
+			if(!do_after(user, 15, TRUE, src)) // give them a few seconds to reconsider their decision.
+				return
+			log_game("[key_name_admin(user)] has opened a firelock with a pressure difference at [AREACOORD(loc)]") // there bibby I made it logged just for you. Enjoy.
+			// since we have high-pressure-ness, close all other firedoors on the tile
+			whack_a_mole()
+		if(welded || operating || !density)
+			return // in case things changed during our do_after
+		emergency_close_timer = world.time + 60 // prevent it from instaclosing again if in space
 		open()
 	else
 		close()
 
+/obj/machinery/door/firedoor/proc/allow_hand_open(mob/user)
+	var/area/A = get_area(src)
+	if(A && A.fire)
+		return FALSE
+	return !is_holding_pressure()
+
 /obj/machinery/door/firedoor/attack_ai(mob/user)
 	add_fingerprint(user)
 	if(welded || operating || stat & NOPOWER)
@@ -171,20 +203,16 @@
 		if("closing")
 			flick("door_closing", src)
 
-/obj/machinery/door/firedoor/update_icon_state()
+/obj/machinery/door/firedoor/update_icon()
+	cut_overlays()
 	if(density)
 		icon_state = "door_closed"
+		if(welded)
+			add_overlay("welded")
 	else
 		icon_state = "door_open"
-
+		if(welded)
-/obj/machinery/door/firedoor/update_overlays()
+			add_overlay("welded_open")
-	. = ..()
-	if(!welded)
-		return
-	if(density)
-		. += "welded"
-	else
-		. += "welded_open"
 
 /obj/machinery/door/firedoor/open()
 	. = ..()
@@ -194,6 +222,61 @@
 	. = ..()
 	latetoggle()
 
+/obj/machinery/door/firedoor/proc/whack_a_mole(reconsider_immediately = FALSE)
+	set waitfor = 0
+	for(var/cdir in GLOB.cardinals)
+		if((flags_1 & ON_BORDER_1) && cdir != dir)
+			continue
+		whack_a_mole_part(get_step(src, cdir), reconsider_immediately)
+	if(flags_1 & ON_BORDER_1)
+		whack_a_mole_part(get_turf(src), reconsider_immediately)
+
+/obj/machinery/door/firedoor/proc/whack_a_mole_part(turf/start_point, reconsider_immediately)
+	set waitfor = 0
+	var/list/doors_to_close = list()
+	var/list/turfs = list()
+	turfs[start_point] = 1
+	for(var/i = 1; (i <= turfs.len && i <= 11); i++) // check up to 11 turfs.
+		var/turf/open/T = turfs[i]
+		if(istype(T, /turf/open/space))
+			return -1
+		for(var/T2 in T.atmos_adjacent_turfs)
+			if(turfs[T2])
+				continue
+			var/is_cut_by_unopen_door = FALSE
+			for(var/obj/machinery/door/firedoor/FD in T2)
+				if((FD.flags_1 & ON_BORDER_1) && get_dir(T2, T) != FD.dir)
+					continue
+				if(FD.operating || FD == src || FD.welded || FD.density)
+					continue
+				doors_to_close += FD
+				is_cut_by_unopen_door = TRUE
+
+			for(var/obj/machinery/door/firedoor/FD in T)
+				if((FD.flags_1 & ON_BORDER_1) && get_dir(T, T2) != FD.dir)
+					continue
+				if(FD.operating || FD == src || FD.welded || FD.density)
+					continue
+				doors_to_close += FD
+				is_cut_by_unopen_door= TRUE
+			if(!is_cut_by_unopen_door)
+				turfs[T2] = 1
+	if(turfs.len > 10)
+		return // too big, don't bother
+	for(var/obj/machinery/door/firedoor/FD in doors_to_close)
+		FD.emergency_pressure_stop(FALSE)
+		if(reconsider_immediately)
+			var/turf/open/T = FD.loc
+			if(istype(T))
+				T.ImmediateCalculateAdjacentTurfs()
+
+/obj/machinery/door/firedoor/proc/emergency_pressure_stop(consider_timer = TRUE)
+	set waitfor = 0
+	if(density || operating || welded)
+		return
+	if(world.time >= emergency_close_timer || !consider_timer)
+		close()
+
 /obj/machinery/door/firedoor/deconstruct(disassembled = TRUE)
 	if(!(flags_1 & NODECONSTRUCT_1))
 		var/obj/structure/firelock_frame/F = new assemblytype(get_turf(src))
@@ -227,6 +310,59 @@
 	opacity = TRUE
 	density = TRUE
 
+/obj/machinery/door/firedoor/border_only/close()
+	if(density)
+		return TRUE
+	if(operating || welded)
+		return
+	var/turf/T1 = get_turf(src)
+	var/turf/T2 = get_step(T1, dir)
+	for(var/mob/living/M in T1)
+		if(M.stat == CONSCIOUS && M.pulling && M.pulling.loc == T2 && !M.pulling.anchored && M.pulling.move_resist <= M.move_force)
+			var/mob/living/M2 = M.pulling
+			if(!istype(M2) || !M2.buckled || !M2.buckled.buckle_prevents_pull)
+				to_chat(M, "<span class='notice'>You pull [M.pulling] through [src] right as it closes</span>")
+				M.pulling.forceMove(T1)
+				M.start_pulling(M2)
+				
+	for(var/mob/living/M in T2)
+		if(M.stat == CONSCIOUS && M.pulling && M.pulling.loc == T1 && !M.pulling.anchored && M.pulling.move_resist <= M.move_force)
+			var/mob/living/M2 = M.pulling
+			if(!istype(M2) || !M2.buckled || !M2.buckled.buckle_prevents_pull)
+				to_chat(M, "<span class='notice'>You pull [M.pulling] through [src] right as it closes</span>")
+				M.pulling.forceMove(T2)
+				M.start_pulling(M2)
+	. = ..()
+
+/obj/machinery/door/firedoor/border_only/allow_hand_open(mob/user)
+	var/area/A = get_area(src)
+	if((!A || !A.fire) && !is_holding_pressure())
+		return TRUE
+	whack_a_mole(TRUE) // WOOP WOOP SIDE EFFECTS
+	var/turf/T = loc
+	var/turf/T2 = get_step(T, dir)
+	if(!T || !T2)
+		return
+	var/status1 = check_door_side(T)
+	var/status2 = check_door_side(T2)
+	if((status1 == 1 && status2 == -1) || (status1 == -1 && status2 == 1))
+		to_chat(user, "<span class='warning'>Access denied. Try closing another firedoor to minimize decompression, or using a crowbar.</span>")
+		return FALSE
+	return TRUE
+
+/obj/machinery/door/firedoor/border_only/proc/check_door_side(turf/open/start_point)
+	var/list/turfs = list()
+	turfs[start_point] = 1
+	for(var/i = 1; (i <= turfs.len && i <= 11); i++) // check up to 11 turfs.
+		var/turf/open/T = turfs[i]
+		if(istype(T, /turf/open/space))
+			return -1
+		for(var/T2 in T.atmos_adjacent_turfs)
+			turfs[T2] = 1
+	if(turfs.len <= 10)
+		return 0 // not big enough to matter
+	return start_point.air.return_pressure() < 20 ? -1 : 1
+
 /obj/machinery/door/firedoor/border_only/CanPass(atom/movable/mover, turf/target)
 	if(istype(mover) && (mover.pass_flags & PASSGLASS))
 		return TRUE
@@ -257,6 +393,18 @@
 	assemblytype = /obj/structure/firelock_frame/heavy
 	max_integrity = 550
 
+/obj/machinery/door/firedoor/window
+	name = "window shutter"
+	icon = 'icons/obj/doors/doorfirewindow.dmi'
+	desc = "A second window that slides in when the original window is broken, designed to protect against hull breaches. Truly a work of genius by NT engineers."
+	glass = TRUE
+	explosion_block = 0
+	max_integrity = 50
+	resistance_flags = 0 // not fireproof
+	heat_proof = FALSE
+
+/obj/machinery/door/firedoor/window/allow_hand_open()
+	return TRUE
 
 /obj/item/electronics/firelock
 	name = "firelock circuitry"
@@ -294,7 +442,7 @@
 /obj/structure/firelock_frame/attackby(obj/item/C, mob/user)
 	switch(constructionStep)
 		if(CONSTRUCTION_PANEL_OPEN)
-			if(istype(C, /obj/item/crowbar))
+			if(C.tool_behaviour == TOOL_CROWBAR)
 				C.play_tool_sound(src)
 				user.visible_message("<span class='notice'>[user] starts prying something out from [src]...</span>", \
 									 "<span class='notice'>You begin prying out the wire cover...</span>")
@@ -308,7 +456,7 @@
 				constructionStep = CONSTRUCTION_WIRES_EXPOSED
 				update_icon()
 				return
-			if(istype(C, /obj/item/wrench))
+			if(C.tool_behaviour == TOOL_WRENCH)
 				if(locate(/obj/machinery/door/firedoor) in get_turf(src))
 					to_chat(user, "<span class='warning'>There's already a firelock there.</span>")
 					return
@@ -350,7 +498,7 @@
 				return
 
 		if(CONSTRUCTION_WIRES_EXPOSED)
-			if(istype(C, /obj/item/wirecutters))
+			if(C.tool_behaviour == TOOL_WIRECUTTER)
 				C.play_tool_sound(src)
 				user.visible_message("<span class='notice'>[user] starts cutting the wires from [src]...</span>", \
 									 "<span class='notice'>You begin removing [src]'s wires...</span>")
@@ -364,7 +512,7 @@
 				constructionStep = CONSTRUCTION_GUTTED
 				update_icon()
 				return
-			if(istype(C, /obj/item/crowbar))
+			if(C.tool_behaviour == TOOL_CROWBAR)
 				C.play_tool_sound(src)
 				user.visible_message("<span class='notice'>[user] starts prying a metal plate into [src]...</span>", \
 									 "<span class='notice'>You begin prying the cover plate back onto [src]...</span>")
@@ -379,7 +527,7 @@
 				update_icon()
 				return
 		if(CONSTRUCTION_GUTTED)
-			if(istype(C, /obj/item/crowbar))
+			if(C.tool_behaviour == TOOL_CROWBAR)
 				user.visible_message("<span class='notice'>[user] begins removing the circuit board from [src]...</span>", \
 									 "<span class='notice'>You begin prying out the circuit board from [src]...</span>")
 				if(!C.use_tool(src, user, 50, volume=50))
@@ -401,7 +549,7 @@
 									 "<span class='notice'>You begin adding wires to [src]...</span>")
 				playsound(get_turf(src), 'sound/items/deconstruct.ogg', 50, 1)
 				if(do_after(user, 60, target = src))
-					if(constructionStep != CONSTRUCTION_GUTTED || !B.use_tool(src, user, 0, 5))
+					if(constructionStep != CONSTRUCTION_GUTTED || B.get_amount() < 5 || !B)
 						return
 					user.visible_message("<span class='notice'>[user] adds wires to [src].</span>", \
 										 "<span class='notice'>You wire [src].</span>")
@@ -410,7 +558,7 @@
 					update_icon()
 				return
 		if(CONSTRUCTION_NOCIRCUIT)
-			if(istype(C, /obj/item/weldingtool))
+			if(C.tool_behaviour == TOOL_WELDER)
 				if(!C.tool_start_check(user, amount=1))
 					return
 				user.visible_message("<span class='notice'>[user] begins cutting apart [src]'s frame...</span>", \

code/game/machinery/shuttle/shuttle_engine.dm

@@ -130,7 +130,7 @@
 	var/deltaTemperature = req_power / heat_cap
 	if(deltaTemperature < 0)
 		return
-	env.temperature += deltaTemperature
+	env.set_temperature(env.return_temperature(),deltaTemperature)
 	air_update_turf()
 
 /obj/machinery/shuttle/engine/default_change_direction_wrench(mob/user, obj/item/I)

code/game/machinery/shuttle/shuttle_heater.dm

@@ -89,8 +89,8 @@
 	var/datum/gas_mixture/air_contents = airs[1]
 	if(!air_contents)
 		return
-	air_contents.volume = gas_capacity
+	air_contents.set_volume(gas_capacity)
-	air_contents.temperature = T20C
+	air_contents.set_temperature(T20C)
 
 /obj/machinery/atmospherics/components/unary/shuttle/heater/proc/hasFuel(var/required)
 	var/datum/gas_mixture/air_contents = airs[1]

code/game/machinery/spaceheater.dm

@@ -83,9 +83,9 @@
 		var/datum/gas_mixture/env = L.return_air()
 
 		var/newMode = HEATER_MODE_STANDBY
-		if(setMode != HEATER_MODE_COOL && env.temperature < targetTemperature - temperatureTolerance)
+		if(setMode != HEATER_MODE_COOL && env.return_temperature() < targetTemperature - temperatureTolerance)
 			newMode = HEATER_MODE_HEAT
-		else if(setMode != HEATER_MODE_HEAT && env.temperature > targetTemperature + temperatureTolerance)
+		else if(setMode != HEATER_MODE_HEAT && env.return_temperature() > targetTemperature + temperatureTolerance)
 			newMode = HEATER_MODE_COOL
 
 		if(mode != newMode)
@@ -96,7 +96,7 @@
 			return
 
 		var/heat_capacity = env.heat_capacity()
-		var/requiredPower = abs(env.temperature - targetTemperature) * heat_capacity
+		var/requiredPower = abs(env.return_temperature() - targetTemperature) * heat_capacity
 		requiredPower = min(requiredPower, heatingPower)
 
 		if(requiredPower < 1)
@@ -106,7 +106,7 @@
 		if(mode == HEATER_MODE_COOL)
 			deltaTemperature *= -1
 		if(deltaTemperature)
-			env.temperature += deltaTemperature
+			env.set_temperature(env.return_temperature() + deltaTemperature)
 			air_update_turf()
 		cell.use(requiredPower / efficiency)
 	else
@@ -194,9 +194,9 @@
 	var/curTemp
 	if(istype(L))
 		var/datum/gas_mixture/env = L.return_air()
-		curTemp = env.temperature
+		curTemp = env.return_temperature()
 	else if(isturf(L))
-		curTemp = L.temperature
+		curTemp = L.return_temperature()
 	if(isnull(curTemp))
 		data["currentTemp"] = "N/A"
 	else

code/game/mecha/combat/honker.dm

@@ -21,7 +21,7 @@
 	var/cell_charge = get_charge()
 	var/datum/gas_mixture/int_tank_air = internal_tank.return_air()
 	var/tank_pressure = internal_tank ? round(int_tank_air.return_pressure(),0.01) : "None"
-	var/tank_temperature = internal_tank ? int_tank_air.temperature : "Unknown"
+	var/tank_temperature = internal_tank ? int_tank_air.return_temperature() : "Unknown"
 	var/cabin_pressure = round(return_pressure(),0.01)
 	var/output = {"[report_internal_damage()]
 						[integrity<30?"<font color='red'><b>DAMAGE LEVEL CRITICAL</b></font><br>":null]

code/game/mecha/equipment/tools/other_tools.dm

@@ -422,13 +422,13 @@
 		return
 	var/datum/gas_mixture/GM = new
 	if(prob(10))
-		GM.gases[/datum/gas/plasma] += 100
+		GM.adjust_moles(/datum/gas/plasma,100)
-		GM.temperature = 1500+T0C //should be enough to start a fire
+		GM.set_temperature(1500+T0C) //should be enough to start a fire
 		T.visible_message("[src] suddenly disgorges a cloud of heated plasma.")
 		qdel(src)
 	else
-		GM.gases[/datum/gas/plasma] += 5
+		GM.adjust_moles(/datum/gas/plasma,5)
-		GM.temperature = istype(T) ? T.air.return_temperature() : T20C
+		GM.set_temperature(istype(T) ? T.air.return_temperature() : T20C)
 		T.visible_message("[src] suddenly disgorges a cloud of plasma.")
 	T.assume_air(GM)
 	return

code/game/mecha/mecha.dm

@@ -247,10 +247,10 @@
 
 /obj/mecha/proc/add_cabin()
 	cabin_air = new
-	cabin_air.temperature = T20C
+	cabin_air.set_temperature(T20C)
-	cabin_air.volume = 200
+	cabin_air.set_volume(200)
-	cabin_air.gases[/datum/gas/oxygen] = O2STANDARD*cabin_air.volume/(R_IDEAL_GAS_EQUATION*cabin_air.temperature)
+	cabin_air.set_moles(/datum/gas/oxygen,O2STANDARD*cabin_air.return_volume()/(R_IDEAL_GAS_EQUATION*cabin_air.return_temperature()))
-	cabin_air.gases[/datum/gas/nitrogen] = N2STANDARD*cabin_air.volume/(R_IDEAL_GAS_EQUATION*cabin_air.temperature)
+	cabin_air.set_moles(/datum/gas/nitrogen,N2STANDARD*cabin_air.return_volume()/(R_IDEAL_GAS_EQUATION*cabin_air.return_temperature()))
 	return cabin_air
 
 /obj/mecha/proc/add_radio()
@@ -302,9 +302,9 @@
 				if(int_tank_air.return_pressure() > internal_tank.maximum_pressure && !(internal_damage & MECHA_INT_TANK_BREACH))
 					setInternalDamage(MECHA_INT_TANK_BREACH)
 				if(int_tank_air && int_tank_air.return_volume() > 0) //heat the air_contents
-					int_tank_air.temperature = min(6000+T0C, int_tank_air.temperature+rand(10,15))
+					int_tank_air.set_temperature(min(6000+T0C, int_tank_air.return_temperature()+rand(10,15)))
 			if(cabin_air && cabin_air.return_volume()>0)
-				cabin_air.temperature = min(6000+T0C, cabin_air.return_temperature()+rand(10,15))
+				cabin_air.set_temperature(min(6000+T0C, cabin_air.return_temperature()+rand(10,15)))
 				if(cabin_air.return_temperature() > max_temperature/2)
 					take_damage(4/round(max_temperature/cabin_air.return_temperature(),0.1), BURN, 0, 0)
 
@@ -329,8 +329,8 @@
 
 	if(internal_temp_regulation)
 		if(cabin_air && cabin_air.return_volume() > 0)
-			var/delta = cabin_air.temperature - T20C
+			var/delta = cabin_air.return_temperature() - T20C
-			cabin_air.temperature -= max(-10, min(10, round(delta/4,0.1)))
+			cabin_air.set_temperature(cabin_air.return_temperature() - max(-10, min(10, round(delta/4,0.1))))
 
 	if(internal_tank)
 		var/datum/gas_mixture/tank_air = internal_tank.return_air()

code/game/mecha/mecha_topic.dm

@@ -75,7 +75,7 @@
 	var/cell_charge = get_charge()
 	var/datum/gas_mixture/int_tank_air = internal_tank.return_air()
 	var/tank_pressure = internal_tank ? round(int_tank_air.return_pressure(),0.01) : "None"
-	var/tank_temperature = internal_tank ? int_tank_air.temperature : "Unknown"
+	var/tank_temperature = internal_tank ? int_tank_air.return_temperature() : "Unknown"
 	var/cabin_pressure = round(return_pressure(),0.01)
 	. = {"[report_internal_damage()]
 						[integrity<30?"<span class='userdanger'>DAMAGE LEVEL CRITICAL</span><br>":null]

code/game/objects/effects/effect_system/effects_foam.dm

@@ -40,12 +40,11 @@
 	if(hotspot && istype(T) && T.air)
 		qdel(hotspot)
 		var/datum/gas_mixture/G = T.air
-		var/plas_amt = min(30,G.gases[/datum/gas/plasma]) //Absorb some plasma
+		var/plas_amt = min(30,G.get_moles(/datum/gas/plasma))  //Absorb some plasma
-		G.gases[/datum/gas/plasma] -= plas_amt
+		G.adjust_moles(/datum/gas/plasma,-plas_amt)
 		absorbed_plasma += plas_amt
-		if(G.temperature > T20C)
+		if(G.return_temperature() > T20C)
-			G.temperature = max(G.temperature/2,T20C)
+			G.set_temperature(max(G.return_temperature()/2,T20C))
-		GAS_GARBAGE_COLLECT(G.gases)
 		T.air_update_turf()
 
 /obj/effect/particle_effect/foam/firefighting/kill_foam()
@@ -317,15 +316,13 @@
 		O.ClearWet()
 		if(O.air)
 			var/datum/gas_mixture/G = O.air
-			G.temperature = 293.15
+			G.set_temperature(293.15)
 			for(var/obj/effect/hotspot/H in O)
 				qdel(H)
-			var/list/G_gases = G.gases
+			for(var/I in G.get_gases())
-			for(var/I in G_gases)
 				if(I == /datum/gas/oxygen || I == /datum/gas/nitrogen)
 					continue
-				G_gases[I] = 0
+				G.set_moles(I, 0)
-			GAS_GARBAGE_COLLECT(G.gases)
 			O.air_update_turf()
 		for(var/obj/machinery/atmospherics/components/unary/U in O)
 			if(!U.welded)

code/game/objects/effects/effect_system/effects_smoke.dm

@@ -166,15 +166,13 @@
 		if(T.air)
 			var/datum/gas_mixture/G = T.air
 			if(!distcheck || get_dist(T, location) < blast) // Otherwise we'll get silliness like people using Nanofrost to kill people through walls with cold air
-				G.temperature = temperature
+				G.set_temperature(temperature)
 			T.air_update_turf()
 			for(var/obj/effect/hotspot/H in T)
 				qdel(H)
-			var/list/G_gases = G.gases
+			if(G.get_moles(/datum/gas/plasma))
-			if(G_gases[/datum/gas/plasma])
+				G.adjust_moles(/datum/gas/nitrogen, G.get_moles(/datum/gas/plasma))
-				G_gases[/datum/gas/nitrogen] += (G_gases[/datum/gas/plasma])
+				G.set_moles(/datum/gas/plasma, 0)
-				G_gases[/datum/gas/plasma] = 0
-				GAS_GARBAGE_COLLECT(G.gases)
 		if (weldvents)
 			for(var/obj/machinery/atmospherics/components/unary/U in T)
 				if(!isnull(U.welded) && !U.welded) //must be an unwelded vent pump or vent scrubber.

code/game/objects/effects/spawners/bombspawner.dm

@@ -19,11 +19,11 @@
 	var/obj/item/tank/internals/plasma/PT = new(V)
 	var/obj/item/tank/internals/oxygen/OT = new(V)
 
-	PT.air_contents.gases[/datum/gas/plasma] = pressure_p*PT.volume/(R_IDEAL_GAS_EQUATION*CELSIUS_TO_KELVIN(temp_p))
+	PT.air_contents.set_moles(/datum/gas/plasma, pressure_p*PT.volume/(R_IDEAL_GAS_EQUATION*CELSIUS_TO_KELVIN(temp_p)))
-	PT.air_contents.temperature = CELSIUS_TO_KELVIN(temp_p)
+	PT.air_contents.set_temperature(CELSIUS_TO_KELVIN(temp_p))
 
-	OT.air_contents.gases[/datum/gas/oxygen] = pressure_o*OT.volume/(R_IDEAL_GAS_EQUATION*CELSIUS_TO_KELVIN(temp_o))
+	OT.air_contents.set_moles(/datum/gas/oxygen, pressure_o*OT.volume/(R_IDEAL_GAS_EQUATION*CELSIUS_TO_KELVIN(temp_o)))
-	OT.air_contents.temperature = CELSIUS_TO_KELVIN(temp_o)
+	OT.air_contents.set_temperature(CELSIUS_TO_KELVIN(temp_o))
 
 	V.tank_one = PT
 	V.tank_two = OT

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

@@ -487,3 +487,14 @@
 
 /obj/effect/constructing_effect/proc/end()
 	qdel(src)
+
+/obj/effect/temp_visual/dir_setting/space_wind
+	icon = 'icons/effects/atmospherics.dmi'
+	icon_state = "space_wind"
+	layer = FLY_LAYER
+	duration = 20
+	mouse_opacity = 0
+
+/obj/effect/temp_visual/dir_setting/space_wind/Initialize(mapload, set_dir, set_alpha = 255)
+	. = ..()
+	alpha = set_alpha

code/game/objects/items/chrono_eraser.dm

@@ -246,9 +246,9 @@
 
 /obj/effect/chrono_field/return_air() //we always have nominal air and temperature
 	var/datum/gas_mixture/GM = new
-	GM.gases[/datum/gas/oxygen] = MOLES_O2STANDARD
+	GM.set_moles(/datum/gas/oxygen, MOLES_O2STANDARD)
-	GM.gases[/datum/gas/nitrogen] = MOLES_N2STANDARD
+	GM.set_moles(/datum/gas/nitrogen, MOLES_N2STANDARD)
-	GM.temperature = T20C
+	GM.set_temperature(T20C)
 	return GM
 
 /obj/effect/chrono_field/Move()

code/game/objects/items/devices/PDA/PDA.dm

@@ -437,7 +437,6 @@ GLOBAL_LIST_EMPTY(PDAs)
 					dat += "Unable to obtain a reading.<br>"
 				else
 					var/datum/gas_mixture/environment = T.return_air()
-					var/list/env_gases = environment.gases
 
 					var/pressure = environment.return_pressure()
 					var/total_moles = environment.total_moles()
@@ -445,12 +444,12 @@ GLOBAL_LIST_EMPTY(PDAs)
 					dat += "Air Pressure: [round(pressure,0.1)] kPa<br>"
 
 					if (total_moles)
-						for(var/id in env_gases)
+						for(var/id in environment.get_gases())
-							var/gas_level = env_gases[id]/total_moles
+							var/gas_level = environment.get_moles(id)/total_moles
 							if(gas_level > 0)
 								dat += "[GLOB.meta_gas_names[id]]: [round(gas_level*100, 0.01)]%<br>"
 
-					dat += "Temperature: [round(environment.temperature-T0C)]&deg;C<br>"
+					dat += "Temperature: [round(environment.return_temperature()-T0C)]&deg;C<br>"
 				dat += "<br>"
 			else//Else it links to the cart menu proc. Although, it really uses menu hub 4--menu 4 doesn't really exist as it simply redirects to hub.
 				dat += cartridge.generate_menu()

code/game/objects/items/devices/scanners.dm

@@ -556,41 +556,38 @@ GENETICS SCANNER
 	else
 		to_chat(user, "<span class='alert'>Pressure: [round(pressure, 0.01)] kPa</span>")
 	if(total_moles)
-		var/list/env_gases = environment.gases
 
-		var/o2_concentration = env_gases[/datum/gas/oxygen]/total_moles
+		var/o2_concentration = environment.get_moles(/datum/gas/oxygen)/total_moles
-		var/n2_concentration = env_gases[/datum/gas/nitrogen]/total_moles
+		var/n2_concentration = environment.get_moles(/datum/gas/nitrogen)/total_moles
-		var/co2_concentration = env_gases[/datum/gas/carbon_dioxide]/total_moles
+		var/co2_concentration = environment.get_moles(/datum/gas/carbon_dioxide)/total_moles
-		var/plasma_concentration = env_gases[/datum/gas/plasma]/total_moles
+		var/plasma_concentration = environment.get_moles(/datum/gas/plasma)/total_moles
 
 		if(abs(n2_concentration - N2STANDARD) < 20)
-			to_chat(user, "<span class='info'>Nitrogen: [round(n2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/nitrogen], 0.01)] mol)</span>")
+			to_chat(user, "<span class='info'>Nitrogen: [round(n2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/nitrogen), 0.01)] mol)</span>")
 		else
-			to_chat(user, "<span class='alert'>Nitrogen: [round(n2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/nitrogen], 0.01)] mol)</span>")
+			to_chat(user, "<span class='alert'>Nitrogen: [round(n2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/nitrogen), 0.01)] mol)</span>")
 
 		if(abs(o2_concentration - O2STANDARD) < 2)
-			to_chat(user, "<span class='info'>Oxygen: [round(o2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/oxygen], 0.01)] mol)</span>")
+			to_chat(user, "<span class='info'>Oxygen: [round(o2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/oxygen), 0.01)] mol)</span>")
 		else
-			to_chat(user, "<span class='alert'>Oxygen: [round(o2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/oxygen], 0.01)] mol)</span>")
+			to_chat(user, "<span class='alert'>Oxygen: [round(o2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/oxygen), 0.01)] mol)</span>")
 
 		if(co2_concentration > 0.01)
-			to_chat(user, "<span class='alert'>CO2: [round(co2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/carbon_dioxide], 0.01)] mol)</span>")
+			to_chat(user, "<span class='alert'>CO2: [round(co2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/carbon_dioxide), 0.01)] mol)</span>")
 		else
-			to_chat(user, "<span class='info'>CO2: [round(co2_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/carbon_dioxide], 0.01)] mol)</span>")
+			to_chat(user, "<span class='info'>CO2: [round(co2_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/carbon_dioxide), 0.01)] mol)</span>")
 
 		if(plasma_concentration > 0.005)
-			to_chat(user, "<span class='alert'>Plasma: [round(plasma_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/plasma], 0.01)] mol)</span>")
+			to_chat(user, "<span class='alert'>Plasma: [round(plasma_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/plasma), 0.01)] mol)</span>")
 		else
-			to_chat(user, "<span class='info'>Plasma: [round(plasma_concentration*100, 0.01)] % ([round(env_gases[/datum/gas/plasma], 0.01)] mol)</span>")
+			to_chat(user, "<span class='info'>Plasma: [round(plasma_concentration*100, 0.01)] % ([round(environment.get_moles(/datum/gas/plasma), 0.01)] mol)</span>")
 
-		GAS_GARBAGE_COLLECT(environment.gases)
+		for(var/id in environment.get_gases())
-
-		for(var/id in env_gases)
 			if(id in GLOB.hardcoded_gases)
 				continue
-			var/gas_concentration = env_gases[id]/total_moles
+			var/gas_concentration = environment.get_moles(id)/total_moles
-			to_chat(user, "<span class='alert'>[GLOB.meta_gas_names[id]]: [round(gas_concentration*100, 0.01)] % ([round(env_gases[id], 0.01)] mol)</span>")
+			to_chat(user, "<span class='alert'>[GLOB.meta_gas_names[id]]: [round(gas_concentration*100, 0.01)] % ([round(environment.get_moles(id), 0.01)] mol)</span>")
-		to_chat(user, "<span class='info'>Temperature: [round(environment.temperature-T0C, 0.01)] &deg;C ([round(environment.temperature, 0.01)] K)</span>")
+		to_chat(user, "<span class='info'>Temperature: [round(environment.return_temperature()-T0C, 0.01)] &deg;C ([round(environment.return_temperature(), 0.01)] K)</span>")
 
 /obj/item/analyzer/AltClick(mob/user) //Barometer output for measuring when the next storm happens
 	. = ..()
@@ -669,8 +666,8 @@ GENETICS SCANNER
 
 		var/total_moles = air_contents.total_moles()
 		var/pressure = air_contents.return_pressure()
-		var/volume = air_contents.return_volume() //could just do mixture.volume... but safety, I guess?
+		var/volume = air_contents.return_volume()
-		var/temperature = air_contents.temperature
+		var/temperature = air_contents.return_temperature()
 		var/cached_scan_results = air_contents.analyzer_results
 
 		if(total_moles > 0)
@@ -678,10 +675,9 @@ GENETICS SCANNER
 			to_chat(user, "<span class='notice'>Volume: [volume] L</span>")
 			to_chat(user, "<span class='notice'>Pressure: [round(pressure,0.01)] kPa</span>")
 
-			var/list/cached_gases = air_contents.gases
+			for(var/id in air_contents.get_gases())
-			for(var/id in cached_gases)
+				var/gas_concentration = air_contents.get_moles(id)/total_moles
-				var/gas_concentration = cached_gases[id]/total_moles
+				to_chat(user, "<span class='notice'>[GLOB.meta_gas_names[id]]: [round(gas_concentration*100, 0.01)] % ([round(air_contents.get_moles(id), 0.01)] mol)</span>")
-				to_chat(user, "<span class='notice'>[GLOB.meta_gas_names[id]]: [round(gas_concentration*100, 0.01)] % ([round(cached_gases[id], 0.01)] mol)</span>")
 			to_chat(user, "<span class='notice'>Temperature: [round(temperature - T0C,0.01)] &deg;C ([round(temperature, 0.01)] K)</span>")
 
 		else

code/game/objects/items/devices/transfer_valve.dm

@@ -168,8 +168,8 @@
 		target_self = TRUE
 	if(change_volume)
 		if(!target_self)
-			target.volume += tank_two.volume
+			target.set_volume(target.return_volume() + tank_two.volume)
-		target.volume += tank_one.air_contents.volume
+		target.set_volume(target.return_volume() + tank_one.air_contents.return_volume())
 	var/datum/gas_mixture/temp
 	temp = tank_one.air_contents.remove_ratio(1)
 	target.merge(temp)
@@ -180,11 +180,11 @@
 /obj/item/transfer_valve/proc/split_gases()
 	if (!valve_open || !tank_one || !tank_two)
 		return
-	var/ratio1 = tank_one.air_contents.volume/tank_two.air_contents.volume
+	var/ratio1 = tank_one.air_contents.return_volume()/tank_two.air_contents.return_volume()
 	var/datum/gas_mixture/temp
 	temp = tank_two.air_contents.remove_ratio(ratio1)
 	tank_one.air_contents.merge(temp)
-	tank_two.air_contents.volume -=  tank_one.air_contents.volume
+	tank_two.air_contents.set_volume(tank_two.air_contents.return_volume() - tank_one.air_contents.return_volume())
 
 	/*
 	Exadv1: I know this isn't how it's going to work, but this was just to check

code/game/objects/items/flamethrower.dm

@@ -204,11 +204,10 @@
 	//TODO: DEFERRED Consider checking to make sure tank pressure is high enough before doing this...
 	//Transfer 5% of current tank air contents to turf
 	var/datum/gas_mixture/air_transfer = ptank.air_contents.remove_ratio(release_amount)
-	if(air_transfer.gases[/datum/gas/plasma])
+	air_transfer.set_moles(/datum/gas/plasma, air_transfer.get_moles(/datum/gas/plasma) * 5)
-		air_transfer.gases[/datum/gas/plasma] *= 5
 	target.assume_air(air_transfer)
 	//Burn it based on transfered gas
-	target.hotspot_expose((ptank.air_contents.temperature*2) + 380,500)
+	target.hotspot_expose((ptank.air_contents.return_temperature()*2) + 380,500)
 	//location.hotspot_expose(1000,500,1)
 	SSair.add_to_active(target, 0)
 

code/game/objects/items/pet_carrier.dm

@@ -253,7 +253,7 @@
 		occupant_gas_supply = new
 	if(isanimal(occupant))
 		var/mob/living/simple_animal/animal = occupant
-		occupant_gas_supply.temperature = animal.minbodytemp //simple animals only care about temperature when their turf isnt a location
+		occupant_gas_supply.set_temperature(animal.minbodytemp) //simple animals only care about temperature when their turf isnt a location
 	else
 		if(ishuman(occupant)) //humans require resistance to cold/heat and living in no air while inside, and lose this when outside
 			ADD_TRAIT(occupant, TRAIT_RESISTCOLD, "bluespace_container_cold_resist")

code/game/objects/items/tanks/jetpack.dm

@@ -21,7 +21,7 @@
 
 /obj/item/tank/jetpack/populate_gas()
 	if(gas_type)
-		air_contents.gases[gas_type] = ((6 * ONE_ATMOSPHERE) * volume / (R_IDEAL_GAS_EQUATION * T20C))
+		air_contents.set_moles(gas_type, ((6 * ONE_ATMOSPHERE) * volume / (R_IDEAL_GAS_EQUATION * T20C)))
 
 
 /obj/item/tank/jetpack/ui_action_click(mob/user, action)

code/game/objects/items/tanks/tank_types.dm

@@ -18,8 +18,9 @@
 	force = 10
 	dog_fashion = /datum/dog_fashion/back
 
+
 /obj/item/tank/internals/oxygen/populate_gas()
-	air_contents.gases[/datum/gas/oxygen] = (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/oxygen, (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
 	return
 
 
@@ -47,8 +48,9 @@
 	force = 10
 
 /obj/item/tank/internals/anesthetic/populate_gas()
-	air_contents.gases[/datum/gas/oxygen] = (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * O2STANDARD
+	air_contents.set_moles(/datum/gas/oxygen, (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * O2STANDARD)
-	air_contents.gases[/datum/gas/nitrous_oxide] = (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * N2STANDARD
+	air_contents.set_moles(/datum/gas/nitrous_oxide, (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * N2STANDARD)
+	return
 
 /*
  * Air
@@ -62,8 +64,9 @@
 	dog_fashion = /datum/dog_fashion/back
 
 /obj/item/tank/internals/air/populate_gas()
-	air_contents.gases[/datum/gas/oxygen] = (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * O2STANDARD
+	air_contents.set_moles(/datum/gas/oxygen, (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * O2STANDARD)
-	air_contents.gases[/datum/gas/nitrogen] = (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * N2STANDARD
+	air_contents.set_moles(/datum/gas/nitrogen, (6*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C) * N2STANDARD)
+	return
 
 
 /*
@@ -79,7 +82,8 @@
 
 
 /obj/item/tank/internals/plasma/populate_gas()
-	air_contents.gases[/datum/gas/plasma] = (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/plasma, (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
+	return
 
 /obj/item/tank/internals/plasma/attackby(obj/item/W, mob/user, params)
 	if(istype(W, /obj/item/flamethrower))
@@ -93,12 +97,16 @@
 		F.update_icon()
 	else
 		return ..()
+
+/obj/item/tank/internals/plasma/full/populate_gas()
+	air_contents.set_moles(/datum/gas/plasma, (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
+
 //Makes empty oxygen tanks spawn without gas
 /obj/item/tank/internals/plasma/empty/populate_gas()
 	return
 
 /obj/item/tank/internals/plasma/full/populate_gas()
-	air_contents.gases[/datum/gas/plasma] = (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/plasma, (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
 
 /*
  * Plasmaman Plasma Tank
@@ -113,10 +121,11 @@
 	distribute_pressure = TANK_DEFAULT_RELEASE_PRESSURE
 
 /obj/item/tank/internals/plasmaman/populate_gas()
-	air_contents.gases[/datum/gas/plasma] = (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/plasma, (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
+	return
 
 /obj/item/tank/internals/plasmaman/full/populate_gas()
-	air_contents.gases[/datum/gas/plasma] = (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/plasma, (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
 	return
 
 
@@ -129,7 +138,7 @@
 	w_class = WEIGHT_CLASS_SMALL //thanks i forgot this
 
 /obj/item/tank/internals/plasmaman/belt/full/populate_gas()
-	air_contents.gases[/datum/gas/plasma] = (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/plasma, (10*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
 	return
 
 //makes empty plasma tanks spawn without gas.
@@ -152,7 +161,7 @@
 
 
 /obj/item/tank/internals/emergency_oxygen/populate_gas()
-	air_contents.gases[/datum/gas/oxygen] = (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C)
+	air_contents.set_moles(/datum/gas/oxygen, (3*ONE_ATMOSPHERE)*volume/(R_IDEAL_GAS_EQUATION*T20C))
 	return
 
 /obj/item/tank/internals/emergency_oxygen/empty/populate_gas()

code/game/objects/items/tanks/tanks.dm

@@ -64,7 +64,7 @@
 	. = ..()
 
 	air_contents = new(volume) //liters
-	air_contents.temperature = T20C
+	air_contents.set_temperature(T20C)
 
 	populate_gas()
 
@@ -92,7 +92,7 @@
 
 	. += "<span class='notice'>The pressure gauge reads [round(src.air_contents.return_pressure(),0.01)] kPa.</span>"
 
-	var/celsius_temperature = src.air_contents.temperature-T0C
+	var/celsius_temperature = src.air_contents.return_temperature()-T0C
 	var/descriptive
 
 	if (celsius_temperature < 20)
@@ -235,7 +235,7 @@
 	if(tank_pressure < distribute_pressure)
 		distribute_pressure = tank_pressure
 
-	var/moles_needed = distribute_pressure*volume_to_return/(R_IDEAL_GAS_EQUATION*air_contents.temperature)
+	var/moles_needed = distribute_pressure*volume_to_return/(R_IDEAL_GAS_EQUATION*air_contents.return_temperature())
 
 	return remove_air(moles_needed)
 

code/game/objects/structures/holosign.dm

@@ -94,7 +94,7 @@
 	alpha = 150
 	resistance_flags = FIRE_PROOF
 
-/obj/structure/holosign/barrier/firelock/blocksTemperature()
+/obj/structure/holosign/barrier/firelock/BlockSuperconductivity()
 	return TRUE
 
 /obj/structure/holosign/barrier/combifan
@@ -110,7 +110,7 @@
 	CanAtmosPass = ATMOS_PASS_NO
 	resistance_flags = FIRE_PROOF
 
-/obj/structure/holosign/barrier/combifan/blocksTemperature()
+/obj/structure/holosign/barrier/combifan/BlockSuperconductivity()
 	return TRUE
 
 /obj/structure/holosign/barrier/combifan/Initialize()

code/game/objects/structures/transit_tubes/station.dm

@@ -152,8 +152,8 @@
 		pod_moving = 0
 		if(!QDELETED(pod))
 			var/datum/gas_mixture/floor_mixture = loc.return_air()
-			ARCHIVE(floor_mixture)
+			floor_mixture.archive()
-			ARCHIVE(pod.air_contents)
+			pod.air_contents.archive()
 			pod.air_contents.share(floor_mixture, 1) //mix the pod's gas mixture with the tile it's on
 			air_update_turf()
 

code/game/objects/structures/transit_tubes/transit_tube_pod.dm

@@ -10,9 +10,9 @@
 
 /obj/structure/transit_tube_pod/Initialize()
 	. = ..()
-	air_contents.gases[/datum/gas/oxygen] = MOLES_O2STANDARD
+	air_contents.set_moles(/datum/gas/oxygen, MOLES_O2STANDARD)
-	air_contents.gases[/datum/gas/nitrogen] = MOLES_N2STANDARD
+	air_contents.set_moles(/datum/gas/nitrogen, MOLES_N2STANDARD)
-	air_contents.temperature = T20C
+	air_contents.set_temperature(T20C)
 
 
 /obj/structure/transit_tube_pod/Destroy()
@@ -181,4 +181,4 @@
 						return
 
 /obj/structure/transit_tube_pod/return_temperature()
-	return air_contents.temperature
+	return air_contents.return_temperature()

code/game/turfs/change_turf.dm

@@ -148,6 +148,7 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 		. = ..()
 		if (!.) // changeturf failed or didn't do anything
 			QDEL_NULL(stashed_air)
+			update_air_ref()
 			return
 		var/turf/open/newTurf = .
 		newTurf.air.copy_from(stashed_air)
@@ -308,24 +309,14 @@ GLOBAL_LIST_INIT(blacklisted_automated_baseturfs, typecacheof(list(
 		return
 
 	var/datum/gas_mixture/total = new//Holders to assimilate air from nearby turfs
-	var/list/total_gases = total.gases
 
 	for(var/T in atmos_adjacent_turfs)
 		var/turf/open/S = T
 		if(!S.air)
 			continue
-		var/list/S_gases = S.air.gases
+		total.merge(S.air)
-		for(var/id in S_gases)
-			total_gases[id] += S_gases[id]
-		total.temperature += S.air.temperature
 
-	air.copy_from(total)
+	air.copy_from(total.remove_ratio(1/turf_count))
-
-	var/list/air_gases = air.gases
-	for(var/id in air_gases)
-		air_gases[id] /= turf_count //Averages contents of the turfs, ignoring walls and the like
-
-	air.temperature /= turf_count
 	SSair.add_to_active(src)
 
 /turf/proc/ReplaceWithLattice()

code/game/turfs/closed.dm

@@ -7,9 +7,14 @@
 	rad_flags = RAD_PROTECT_CONTENTS | RAD_NO_CONTAMINATE
 	rad_insulation = RAD_MEDIUM_INSULATION
 
+/turf/closed/Initialize()
+	. = ..()
+	update_air_ref()
+
 /turf/closed/AfterChange()
 	. = ..()
 	SSair.high_pressure_delta -= src
+	update_air_ref()
 
 /turf/closed/get_smooth_underlay_icon(mutable_appearance/underlay_appearance, turf/asking_turf, adjacency_dir)
 	return FALSE

code/game/turfs/open.dm

@@ -199,7 +199,7 @@
 			flash_color(L, flash_color = "#C80000", flash_time = 10)
 
 /turf/open/Initalize_Atmos(times_fired)
-	excited = 0
+	set_excited(FALSE)
 	update_visuals()
 
 	current_cycle = times_fired
@@ -207,19 +207,19 @@
 	for(var/i in atmos_adjacent_turfs)
 		var/turf/open/enemy_tile = i
 		var/datum/gas_mixture/enemy_air = enemy_tile.return_air()
-		if(!excited && air.compare(enemy_air))
+		if(!get_excited() && air.compare(enemy_air))
 			//testing("Active turf found. Return value of compare(): [is_active]")
-			excited = TRUE
+			set_excited(TRUE)
 			SSair.active_turfs |= src
 
 /turf/open/proc/GetHeatCapacity()
 	. = air.heat_capacity()
 
 /turf/open/proc/GetTemperature()
-	. = air.temperature
+	. = air.return_temperature()
 
 /turf/open/proc/TakeTemperature(temp)
-	air.temperature += temp
+	air.set_temperature(air.return_temperature() + temp)
 	air_update_turf()
 
 /turf/open/proc/freon_gas_act()
@@ -304,9 +304,8 @@
 
 /turf/open/rad_act(pulse_strength)
 	. = ..()
-	if (air.gases[/datum/gas/carbon_dioxide] && air.gases[/datum/gas/oxygen])
+	if (air.get_moles(/datum/gas/carbon_dioxide) && air.get_moles(/datum/gas/oxygen))
-		pulse_strength = min(pulse_strength,air.gases[/datum/gas/carbon_dioxide]*1000,air.gases[/datum/gas/oxygen]*2000) //Ensures matter is conserved properly
+		pulse_strength = min(pulse_strength,air.get_moles(/datum/gas/carbon_dioxide)*1000,air.get_moles(/datum/gas/oxygen)*2000) //Ensures matter is conserved properly
-		air.gases[/datum/gas/carbon_dioxide]=max(air.gases[/datum/gas/carbon_dioxide]-(pulse_strength/1000),0)
+		air.set_moles(/datum/gas/carbon_dioxide, max(air.get_moles(/datum/gas/carbon_dioxide)-(pulse_strength/1000),0))
-		air.gases[/datum/gas/oxygen]=max(air.gases[/datum/gas/oxygen]-(pulse_strength/2000),0)
+		air.set_moles(/datum/gas/oxygen, max(air.get_moles(/datum/gas/oxygen)-(pulse_strength/2000),0))
-		air.gases[/datum/gas/pluoxium]+=(pulse_strength/4000)
+		air.adjust_moles(/datum/gas/pluoxium, pulse_strength/4000)
-		GAS_GARBAGE_COLLECT(air.gases)

code/game/turfs/space/space.dm

@@ -27,6 +27,7 @@
 /turf/open/space/Initialize()
 	icon_state = SPACE_ICON_STATE
 	air = space_gas
+	update_air_ref()
 	vis_contents.Cut() //removes inherited overlays
 	visibilityChanged()
 

code/game/turfs/turf.dm

@@ -277,7 +277,7 @@
 /turf/open/Entered(atom/movable/AM)
 	..()
 	//melting
-	if(isobj(AM) && air && air.temperature > T0C)
+	if(isobj(AM) && air && air.return_temperature() > T0C)
 		var/obj/O = AM
 		if(O.obj_flags & FROZEN)
 			O.make_unfrozen()

code/game/world.dm

@@ -9,9 +9,8 @@ GLOBAL_LIST(topic_status_cache)
 //This happens after the Master subsystem new(s) (it's a global datum)
 //So subsystems globals exist, but are not initialised
 /world/New()
-	var/extools = world.GetConfig("env", "EXTOOLS_DLL") || "./byond-extools.dll"
+	if (fexists(EXTOOLS))
-	if (fexists(extools))
+		call(EXTOOLS, "maptick_initialize")()
-		call(extools, "maptick_initialize")()
 	enable_debugger()
 
 	world.Profile(PROFILE_START)
@@ -276,6 +275,15 @@ GLOBAL_LIST(topic_status_cache)
 	shutdown_logging() // Past this point, no logging procs can be used, at risk of data loss.
 	..()
 
+/world/Del()
+	// memory leaks bad
+	var/num_deleted = 0
+	for(var/datum/gas_mixture/GM)
+		GM.__gasmixture_unregister()
+		num_deleted++
+	log_world("Deallocated [num_deleted] gas mixtures")
+	..()
+
 /world/proc/update_status()
 
 	var/list/features = list()
@@ -344,3 +352,6 @@ GLOBAL_LIST(topic_status_cache)
 	maxz++
 	SSmobs.MaxZChanged()
 	SSidlenpcpool.MaxZChanged()
+	world.refresh_atmos_grid()
+
+/world/proc/refresh_atmos_grid()

code/modules/admin/verbs/debug.dm

@@ -573,7 +573,7 @@
 		if(Rad.anchored)
 			if(!Rad.loaded_tank)
 				var/obj/item/tank/internals/plasma/Plasma = new/obj/item/tank/internals/plasma(Rad)
-				Plasma.air_contents.gases[/datum/gas/plasma] = 70
+				Plasma.air_contents.set_moles(/datum/gas/plasma,70)
 				Rad.drainratio = 0
 				Rad.loaded_tank = Plasma
 				Plasma.forceMove(Rad)

code/modules/admin/verbs/diagnostics.dm

@@ -1,15 +1,14 @@
 /proc/show_air_status_to(turf/target, mob/user)
 	var/datum/gas_mixture/env = target.return_air()
-	var/list/env_gases = env.gases
 	var/burning = FALSE
 	if(isopenturf(target))
 		var/turf/open/T = target
 		if(T.active_hotspot)
 			burning = TRUE
 
-	var/list/lines = list("<span class='adminnotice'>[AREACOORD(target)]: [env.temperature] K ([env.temperature - T0C] C), [env.return_pressure()] kPa[(burning)?(", <font color='red'>burning</font>"):(null)]</span>")
+	var/list/lines = list("<span class='adminnotice'>[AREACOORD(target)]: [env.return_temperature()] K ([env.return_temperature() - T0C] C), [env.return_pressure()] kPa[(burning)?(", <font color='red'>burning</font>"):(null)]</span>")
-	for(var/id in env_gases)
+	for(var/id in env.get_gases())
-		var/moles = env_gases[id]
+		var/moles = env.get_moles(id)
 		if (moles >= 0.00001)
 			lines += "[GLOB.meta_gas_names[id]]: [moles] mol"
 	to_chat(usr, lines.Join("\n"))

code/modules/assembly/bomb.dm

@@ -53,8 +53,8 @@
 		return
 	if(I.use_tool(src, user, 0, volume=40))
 		status = TRUE
-		GLOB.bombers += "[key_name(user)] welded a single tank bomb. Temp: [bombtank.air_contents.temperature-T0C]"
+		GLOB.bombers += "[key_name(user)] welded a single tank bomb. Temp: [bombtank.air_contents.return_temperature()-T0C]"
-		message_admins("[ADMIN_LOOKUPFLW(user)] welded a single tank bomb. Temp: [bombtank.air_contents.temperature-T0C]")
+		message_admins("[ADMIN_LOOKUPFLW(user)] welded a single tank bomb. Temp: [bombtank.air_contents.return_temperature()-T0C]")
 		to_chat(user, "<span class='notice'>A pressure hole has been bored to [bombtank] valve. \The [bombtank] can now be ignited.</span>")
 		add_fingerprint(user)
 		return TRUE
@@ -145,8 +145,7 @@
 	return
 
 /obj/item/tank/proc/ignite()	//This happens when a bomb is told to explode
-	var/fuel_moles = air_contents.gases[/datum/gas/plasma] + air_contents.gases[/datum/gas/oxygen]/6
+	var/fuel_moles = air_contents.get_moles(/datum/gas/plasma) + air_contents.get_moles(/datum/gas/oxygen)/6
-	GAS_GARBAGE_COLLECT(air_contents.gases)
 	var/datum/gas_mixture/bomb_mixture = air_contents.copy()
 	var/strength = 1
 
@@ -156,7 +155,7 @@
 		qdel(master)
 	qdel(src)
 
-	if(bomb_mixture.temperature > (T0C + 400))
+	if(bomb_mixture.return_temperature() > (T0C + 400))
 		strength = (fuel_moles/15)
 
 		if(strength >=1)
@@ -169,7 +168,7 @@
 			ground_zero.assume_air(bomb_mixture)
 			ground_zero.hotspot_expose(1000, 125)
 
-	else if(bomb_mixture.temperature > (T0C + 250))
+	else if(bomb_mixture.return_temperature() > (T0C + 250))
 		strength = (fuel_moles/20)
 
 		if(strength >=1)
@@ -180,7 +179,7 @@
 			ground_zero.assume_air(bomb_mixture)
 			ground_zero.hotspot_expose(1000, 125)
 
-	else if(bomb_mixture.temperature > (T0C + 100))
+	else if(bomb_mixture.return_temperature() > (T0C + 100))
 		strength = (fuel_moles/25)
 
 		if (strength >=1)

code/modules/atmospherics/environmental/LINDA_fire.dm

@@ -9,46 +9,31 @@
 	return
 
 
-/turf/open/hotspot_expose(exposed_temperature, exposed_volume, soh = FALSE, holo = FALSE)
+/turf/open/hotspot_expose(exposed_temperature, exposed_volume, soh)
-	var/datum/gas_mixture/air_contents = return_air()
+	if(!air)
-	if(!air_contents)
+		return
-		return 0
 
-	var/oxy = air_contents.gases[/datum/gas/oxygen]
+	var/oxy = air.get_moles(/datum/gas/oxygen)
-	var/tox = air_contents.gases[/datum/gas/plasma]
+	if (oxy < 0.5)
-	var/trit = air_contents.gases[/datum/gas/tritium]
+		return
+	var/tox = air.get_moles(/datum/gas/plasma)
+	var/trit = air.get_moles(/datum/gas/tritium)
 	if(active_hotspot)
 		if(soh)
-			if((tox > 0.5 || trit > 0.5) && oxy > 0.5)
+			if(tox > 0.5 || trit > 0.5)
-				if(active_hotspot.temperature < exposed_temperature*50)
+				if(active_hotspot.temperature < exposed_temperature)
-					active_hotspot.temperature = exposed_temperature*50
+					active_hotspot.temperature = exposed_temperature
 				if(active_hotspot.volume < exposed_volume)
 					active_hotspot.volume = exposed_volume
-		return 1
+		return
-
-	var/igniting = 0
 
 	if((exposed_temperature > PLASMA_MINIMUM_BURN_TEMPERATURE) && (tox > 0.5 || trit > 0.5))
-		igniting = 1
 
-	if(igniting)
+		active_hotspot = new /obj/effect/hotspot(src, exposed_volume*25, exposed_temperature)
-		if(oxy < 0.5)
-			return 0
-
-		active_hotspot = new /obj/effect/hotspot(src, holo)
-		active_hotspot.temperature = exposed_temperature*50
-		active_hotspot.volume = exposed_volume*25
 
 		active_hotspot.just_spawned = (current_cycle < SSair.times_fired)
 			//remove just_spawned protection if no longer processing this cell
 		SSair.add_to_active(src, 0)
-	else
-		var/datum/gas_mixture/heating = air_contents.remove_ratio(exposed_volume/air_contents.volume)
-		heating.temperature = exposed_temperature
-		heating.react()
-		assume_air(heating)
-		air_update_turf()
-	return igniting
 
 //This is the icon for fire on turfs, also helps for nurturing small fires until they are full tile
 /obj/effect/hotspot
@@ -67,11 +52,13 @@
 	var/bypassing = FALSE
 	var/visual_update_tick = 0
 
-/obj/effect/hotspot/Initialize(mapload, holo = FALSE)
+/obj/effect/hotspot/Initialize(mapload, starting_volume, starting_temperature)
 	. = ..()
-	if(holo)
-		flags_1 |= HOLOGRAM_1
 	SSair.hotspots += src
+	if(!isnull(starting_volume))
+		volume = starting_volume
+	if(!isnull(starting_temperature))
+		temperature = starting_temperature
 	perform_exposure()
 	setDir(pick(GLOB.cardinals))
 	air_update_turf()
@@ -83,22 +70,19 @@
 
 	location.active_hotspot = src
 
-	if(volume > CELL_VOLUME*0.95)
+	bypassing = !just_spawned && (volume > CELL_VOLUME*0.95)
-		bypassing = TRUE
-	else
-		bypassing = FALSE
 
 	if(bypassing)
-		if(!just_spawned)
+		volume = location.air.reaction_results["fire"]*FIRE_GROWTH_RATE
-			volume = location.air.reaction_results["fire"]*FIRE_GROWTH_RATE
+		temperature = location.air.return_temperature()
-			temperature = location.air.temperature
 	else
-		var/datum/gas_mixture/affected = location.air.remove_ratio(volume/location.air.volume)
+		var/datum/gas_mixture/affected = location.air.remove_ratio(volume/location.air.return_volume())
-		affected.temperature = temperature
+		if(affected) //in case volume is 0
-		affected.react(src)
+			affected.set_temperature(temperature)
-		temperature = affected.temperature
+			affected.react(src)
-		volume = affected.reaction_results["fire"]*FIRE_GROWTH_RATE
+			temperature = affected.return_temperature()
-		location.assume_air(affected)
+			volume = affected.reaction_results["fire"]*FIRE_GROWTH_RATE
+			location.assume_air(affected)
 
 	for(var/A in location)
 		var/atom/AT = A
@@ -164,7 +148,7 @@
 	color = list(LERP(0.3, 1, 1-greyscale_fire) * heat_r,0.3 * heat_g * greyscale_fire,0.3 * heat_b * greyscale_fire, 0.59 * heat_r * greyscale_fire,LERP(0.59, 1, 1-greyscale_fire) * heat_g,0.59 * heat_b * greyscale_fire, 0.11 * heat_r * greyscale_fire,0.11 * heat_g * greyscale_fire,LERP(0.11, 1, 1-greyscale_fire) * heat_b, 0,0,0)
 	alpha = heat_a
 
-#define INSUFFICIENT(path) (location.air.gases[path] < 0.5)
+#define INSUFFICIENT(path) (location.air.get_moles(path) < 0.5)
 /obj/effect/hotspot/process()
 	if(just_spawned)
 		just_spawned = FALSE
@@ -175,8 +159,7 @@
 		qdel(src)
 		return
 
-	if(location.excited_group)
+	location.eg_reset_cooldowns()
-		location.excited_group.reset_cooldowns()
 
 	if((temperature < FIRE_MINIMUM_TEMPERATURE_TO_EXIST) || (volume <= 1))
 		qdel(src)
@@ -186,7 +169,8 @@
 		return
 
 	//Not enough to burn
-	if((location.air.gases[/datum/gas/plasma] < 0.5 && location.air.gases[/datum/gas/tritium] < 0.5) || location.air.gases[/datum/gas/oxygen] < 0.5)
+	// god damn it previous coder you made the INSUFFICIENT macro for a fucking reason why didn't you use it here smh
+	if((INSUFFICIENT(/datum/gas/plasma) && INSUFFICIENT(/datum/gas/tritium)) || INSUFFICIENT(/datum/gas/oxygen))
 		qdel(src)
 		return
 
@@ -194,16 +178,15 @@
 
 	if(bypassing)
 		icon_state = "3"
-		if(!(flags_1 & HOLOGRAM_1))
+		location.burn_tile()
-			location.burn_tile()
 
 		//Possible spread due to radiated heat
-		if(location.air.temperature > FIRE_MINIMUM_TEMPERATURE_TO_SPREAD)
+		if(location.air.return_temperature() > FIRE_MINIMUM_TEMPERATURE_TO_SPREAD)
-			var/radiated_temperature = location.air.temperature*FIRE_SPREAD_RADIOSITY_SCALE
+			var/radiated_temperature = location.air.return_temperature()*FIRE_SPREAD_RADIOSITY_SCALE
 			for(var/t in location.atmos_adjacent_turfs)
 				var/turf/open/T = t
 				if(!T.active_hotspot)
-					T.hotspot_expose(radiated_temperature, CELL_VOLUME/4, flags_1 & HOLOGRAM_1)
+					T.hotspot_expose(radiated_temperature, CELL_VOLUME/4)
 
 	else
 		if(volume > CELL_VOLUME*0.4)
@@ -227,14 +210,13 @@
 	var/turf/open/T = loc
 	if(istype(T) && T.active_hotspot == src)
 		T.active_hotspot = null
-	if(!(flags_1 & HOLOGRAM_1))
+	DestroyTurf()
-		DestroyTurf()
 	return ..()
 
 /obj/effect/hotspot/proc/DestroyTurf()
 	if(isturf(loc))
 		var/turf/T = loc
-		if(T.to_be_destroyed)
+		if(T.to_be_destroyed && !T.changing_turf)
 			var/chance_of_deletion
 			if (T.heat_capacity) //beware of division by zero
 				chance_of_deletion = T.max_fire_temperature_sustained / T.heat_capacity * 8 //there is no problem with prob(23456), min() was redundant --rastaf0

code/modules/atmospherics/environmental/LINDA_system.dm

@@ -18,7 +18,7 @@
 
 /turf/open/CanAtmosPass(turf/T, vertical = FALSE)
 	var/dir = vertical? get_dir_multiz(src, T) : get_dir(src, T)
-	var/opp = dir_inverse_multiz(dir)
+	var/opp = REVERSE_DIR(dir)
 	var/R = FALSE
 	if(vertical && !(zAirOut(dir, T) && T.zAirIn(dir, src)))
 		R = TRUE
@@ -48,21 +48,28 @@
 	var/canvpass = CANVERTICALATMOSPASS(src, src)
 	for(var/direction in GLOB.cardinals_multiz)
 		var/turf/T = get_step_multiz(src, direction)
+		var/opp_dir = REVERSE_DIR(direction)
 		if(!isopenturf(T))
 			continue
 		if(!(blocks_air || T.blocks_air) && ((direction & (UP|DOWN))? (canvpass && CANVERTICALATMOSPASS(T, src)) : (canpass && CANATMOSPASS(T, src))) )
 			LAZYINITLIST(atmos_adjacent_turfs)
 			LAZYINITLIST(T.atmos_adjacent_turfs)
-			atmos_adjacent_turfs[T] = TRUE
+			atmos_adjacent_turfs[T] = direction
-			T.atmos_adjacent_turfs[src] = TRUE
+			T.atmos_adjacent_turfs[src] = opp_dir
+			T.__update_extools_adjacent_turfs()
 		else
 			if (atmos_adjacent_turfs)
 				atmos_adjacent_turfs -= T
 			if (T.atmos_adjacent_turfs)
 				T.atmos_adjacent_turfs -= src
+				T.__update_extools_adjacent_turfs()
 			UNSETEMPTY(T.atmos_adjacent_turfs)
 	UNSETEMPTY(atmos_adjacent_turfs)
 	src.atmos_adjacent_turfs = atmos_adjacent_turfs
+	__update_extools_adjacent_turfs()
+
+/turf/proc/__update_extools_adjacent_turfs()
+
 
 //returns a list of adjacent turfs that can share air with this one.
 //alldir includes adjacent diagonal tiles that can share
@@ -111,9 +118,9 @@
 	SSair.add_to_active(src,command)
 
 /atom/movable/proc/move_update_air(turf/T)
-	if(isturf(T))
+    if(isturf(T))
-		T.air_update_turf(1)
+        T.air_update_turf(1)
-	air_update_turf(1)
+    air_update_turf(1)
 
 /atom/proc/atmos_spawn_air(text) //because a lot of people loves to copy paste awful code lets just make an easy proc to spawn your plasma fires
 	var/turf/open/T = get_turf(src)

code/modules/atmospherics/environmental/LINDA_turf_tile.dm

@@ -8,6 +8,7 @@
 	var/list/atmos_adjacent_turfs
 	//bitfield of dirs in which we are superconducitng
 	var/atmos_supeconductivity = NONE
+	var/is_openturf = FALSE // used by extools shizz.
 
 	//used to determine whether we should archive
 	var/archived_cycle = 0
@@ -23,21 +24,21 @@
 	//used for spacewind
 	var/pressure_difference = 0
 	var/pressure_direction = 0
+	var/turf/pressure_specific_target
 
-	var/datum/excited_group/excited_group
-	var/excited = FALSE
 	var/datum/gas_mixture/turf/air
 
 	var/obj/effect/hotspot/active_hotspot
-	var/atmos_cooldown  = 0
 	var/planetary_atmos = FALSE //air will revert to initial_gas_mix over time
 
 	var/list/atmos_overlay_types //gas IDs of current active gas overlays
+	is_openturf = TRUE
 
 /turf/open/Initialize()
 	if(!blocks_air)
 		air = new
 		air.copy_from_turf(src)
+		update_air_ref()
 	. = ..()
 
 /turf/open/Destroy()
@@ -48,6 +49,8 @@
 		SSair.add_to_active(T)
 	return ..()
 
+/turf/proc/update_air_ref()
+
 /////////////////GAS MIXTURE PROCS///////////////////
 
 /turf/open/assume_air(datum/gas_mixture/giver) //use this for machines to adjust air
@@ -89,15 +92,37 @@
 	temperature_archived = temperature
 
 /turf/open/archive()
-	ARCHIVE(air)
+	air.archive()
 	archived_cycle = SSair.times_fired
 	temperature_archived = temperature
 
+/turf/open/proc/eg_reset_cooldowns()
+/turf/open/proc/eg_garbage_collect()
+/turf/open/proc/get_excited()
+/turf/open/proc/set_excited()
+
 /////////////////////////GAS OVERLAYS//////////////////////////////
 
+
 /turf/open/proc/update_visuals()
-	var/list/new_overlay_types = tile_graphic()
+
 	var/list/atmos_overlay_types = src.atmos_overlay_types // Cache for free performance
+	var/list/new_overlay_types = list()
+	var/static/list/nonoverlaying_gases = typecache_of_gases_with_no_overlays()
+
+	if(!air) // 2019-05-14: was not able to get this path to fire in testing. Consider removing/looking at callers -Naksu
+		if (atmos_overlay_types)
+			for(var/overlay in atmos_overlay_types)
+				vis_contents -= overlay
+			src.atmos_overlay_types = null
+		return
+
+	for(var/id in air.get_gases())
+		if (nonoverlaying_gases[id])
+			continue
+		var/gas_overlay = GLOB.meta_gas_overlays[id]
+		if(gas_overlay && air.get_moles(id) > GLOB.meta_gas_visibility[META_GAS_MOLES_VISIBLE])
+			new_overlay_types += gas_overlay[min(FACTOR_GAS_VISIBLE_MAX, CEILING(air.get_moles(id) / MOLES_GAS_VISIBLE_STEP, 1))]
 
 	if (atmos_overlay_types)
 		for(var/overlay in atmos_overlay_types-new_overlay_types) //doesn't remove overlays that would only be added
@@ -112,19 +137,18 @@
 	UNSETEMPTY(new_overlay_types)
 	src.atmos_overlay_types = new_overlay_types
 
-/turf/open/proc/tile_graphic()
+/turf/open/proc/set_visuals(list/new_overlay_types)
-	var/static/list/nonoverlaying_gases = typecache_of_gases_with_no_overlays()
+	if (atmos_overlay_types)
-	if(!air)
+		for(var/overlay in atmos_overlay_types-new_overlay_types) //doesn't remove overlays that would only be added
-		return
+			vis_contents -= overlay
-	. = new /list
+
-	var/list/gases = air.gases
+	if (length(new_overlay_types))
-	for(var/id in gases)
+		if (atmos_overlay_types)
-		if (nonoverlaying_gases[id])
+			vis_contents += new_overlay_types - atmos_overlay_types //don't add overlays that already exist
-			continue
+		else
-		var/gas = gases[id]
+			vis_contents += new_overlay_types
-		var/gas_overlay = GLOB.meta_gas_overlays[id]
+	UNSETEMPTY(new_overlay_types)
-		if(gas_overlay && gas > GLOB.meta_gas_visibility[id])
+	src.atmos_overlay_types = new_overlay_types
-			. += gas_overlay[min(FACTOR_GAS_VISIBLE_MAX, CEILING(gas / MOLES_GAS_VISIBLE_STEP, 1))]
 
 /proc/typecache_of_gases_with_no_overlays()
 	. = list()
@@ -135,8 +159,8 @@
 
 /////////////////////////////SIMULATION///////////////////////////////////
 
-#define LAST_SHARE_CHECK \
+/*#define LAST_SHARE_CHECK \
-	var/last_share = our_air.last_share;\
+	var/last_share = our_air.get_last_share();\
 	if(last_share > MINIMUM_AIR_TO_SUSPEND){\
 		our_excited_group.reset_cooldowns();\
 		cached_atmos_cooldown = 0;\
@@ -144,107 +168,32 @@
 		our_excited_group.dismantle_cooldown = 0;\
 		cached_atmos_cooldown = 0;\
 	}
-
+*/
 /turf/proc/process_cell(fire_count)
 	SSair.remove_from_active(src)
 
-/turf/open/process_cell(fire_count)
+/turf/open/proc/equalize_pressure_in_zone(cyclenum)
-	if(archived_cycle < fire_count) //archive self if not already done
+/turf/open/proc/consider_firelocks(turf/T2)
-		archive()
+	var/reconsider_adj = FALSE
-
+	for(var/obj/machinery/door/firedoor/FD in T2)
-	current_cycle = fire_count
+		if((FD.flags_1 & ON_BORDER_1) && get_dir(T2, src) != FD.dir)
-
-	//cache for sanic speed
-	var/list/adjacent_turfs = atmos_adjacent_turfs
-	var/datum/excited_group/our_excited_group = excited_group
-	var/adjacent_turfs_length = LAZYLEN(adjacent_turfs)
-	var/cached_atmos_cooldown = atmos_cooldown + 1
-
-	var/planet_atmos = planetary_atmos
-	if (planet_atmos)
-		adjacent_turfs_length++
-
-	var/datum/gas_mixture/our_air = air
-
-	for(var/t in adjacent_turfs)
-		var/turf/open/enemy_tile = t
-
-		if(fire_count <= enemy_tile.current_cycle)
 			continue
-		enemy_tile.archive()
+		FD.emergency_pressure_stop()
+		reconsider_adj = TRUE
+	for(var/obj/machinery/door/firedoor/FD in src)
+		if((FD.flags_1 & ON_BORDER_1) && get_dir(src, T2) != FD.dir)
+			continue
+		FD.emergency_pressure_stop()
+		reconsider_adj = TRUE
+	if(reconsider_adj)
+		T2.ImmediateCalculateAdjacentTurfs() // We want those firelocks closed yesterday.
 
-	/******************* GROUP HANDLING START *****************************************************************/
+/turf/proc/handle_decompression_floor_rip()
+/turf/open/floor/handle_decompression_floor_rip(sum)
+	if(sum > 20 && prob(clamp(sum / 10, 0, 30)))
+		remove_tile()
 
-		var/should_share_air = FALSE
+/turf/open/process_cell(fire_count)
-		var/datum/gas_mixture/enemy_air = enemy_tile.air
-
-		//cache for sanic speed
-		var/datum/excited_group/enemy_excited_group = enemy_tile.excited_group
-
-		if(our_excited_group && enemy_excited_group)
-			if(our_excited_group != enemy_excited_group)
-				//combine groups (this also handles updating the excited_group var of all involved turfs)
-				our_excited_group.merge_groups(enemy_excited_group)
-				our_excited_group = excited_group //update our cache
-			should_share_air = TRUE
-
-		else if(our_air.compare(enemy_air))
-			if(!enemy_tile.excited)
-				SSair.add_to_active(enemy_tile)
-			var/datum/excited_group/EG = our_excited_group || enemy_excited_group || new
-			if(!our_excited_group)
-				EG.add_turf(src)
-			if(!enemy_excited_group)
-				EG.add_turf(enemy_tile)
-			our_excited_group = excited_group
-			should_share_air = TRUE
-
-		//air sharing
-		if(should_share_air)
-			var/difference = our_air.share(enemy_air, adjacent_turfs_length)
-			if(difference)
-				if(difference > 0)
-					consider_pressure_difference(enemy_tile, difference)
-				else
-					enemy_tile.consider_pressure_difference(src, -difference)
-			LAST_SHARE_CHECK
-
-
-	/******************* GROUP HANDLING FINISH *********************************************************************/
-
-	if (planet_atmos) //share our air with the "atmosphere" "above" the turf
-		var/datum/gas_mixture/G = new
-		G.copy_from_turf(src)
-		ARCHIVE(G)
-		if(our_air.compare(G))
-			if(!our_excited_group)
-				var/datum/excited_group/EG = new
-				EG.add_turf(src)
-				our_excited_group = excited_group
-			our_air.share(G, adjacent_turfs_length)
-			LAST_SHARE_CHECK
-
-	SSair.add_to_react_queue(src)
-
-	if((!our_excited_group && !(our_air.temperature > MINIMUM_TEMPERATURE_START_SUPERCONDUCTION && consider_superconductivity(starting = TRUE))) \
-	  || (cached_atmos_cooldown > (EXCITED_GROUP_DISMANTLE_CYCLES * 2)))
-		SSair.remove_from_active(src)
-
-	atmos_cooldown = cached_atmos_cooldown
-
-/turf/open/space/process_cell(fire_count) //dumb hack to prevent space pollution
-	. = ..()
-	var/datum/gas_mixture/immutable/I = space_gas
-	I.after_process_cell()
-
-/turf/proc/process_cell_reaction()
-	SSair.remove_from_react_queue(src)
-
-/turf/open/process_cell_reaction()
-	air.react(src)
-	update_visuals()
-	SSair.remove_from_react_queue(src)
-	return
 
 //////////////////////////SPACEWIND/////////////////////////////
 
@@ -256,15 +205,22 @@
 
 /turf/open/proc/high_pressure_movements()
 	var/atom/movable/M
+	var/multiplier = 1
+	if(locate(/obj/structure/rack) in src)
+		multiplier *= 0.1
+	else if(locate(/obj/structure/table) in src)
+		multiplier *= 0.2
 	for(var/thing in src)
 		M = thing
 		if (!M.anchored && !M.pulledby && M.last_high_pressure_movement_air_cycle < SSair.times_fired)
-			M.experience_pressure_difference(pressure_difference, pressure_direction)
+			M.experience_pressure_difference(pressure_difference * multiplier, pressure_direction, 0, pressure_specific_target)
+	if(pressure_difference > 100)
+		new /obj/effect/temp_visual/dir_setting/space_wind(src, pressure_direction, clamp(round(sqrt(pressure_difference) * 2), 10, 255))
 
 /atom/movable/var/pressure_resistance = 10
 /atom/movable/var/last_high_pressure_movement_air_cycle = 0
 
-/atom/movable/proc/experience_pressure_difference(pressure_difference, direction, pressure_resistance_prob_delta = 0)
+/atom/movable/proc/experience_pressure_difference(pressure_difference, direction, pressure_resistance_prob_delta = 0, throw_target)
 	var/const/PROBABILITY_OFFSET = 25
 	var/const/PROBABILITY_BASE_PRECENT = 75
 	var/max_force = sqrt(pressure_difference)*(MOVE_FORCE_DEFAULT / 5)
@@ -275,93 +231,8 @@
 	move_prob += pressure_resistance_prob_delta
 	if (move_prob > PROBABILITY_OFFSET && prob(move_prob) && (move_resist != INFINITY) && (!anchored && (max_force >= (move_resist * MOVE_FORCE_PUSH_RATIO))) || (anchored && (max_force >= (move_resist * MOVE_FORCE_FORCEPUSH_RATIO))))
 		step(src, direction)
-		last_high_pressure_movement_air_cycle = SSair.times_fired
-
-///////////////////////////EXCITED GROUPS/////////////////////////////
-
-/datum/excited_group
-	var/list/turf_list = list()
-	var/breakdown_cooldown = 0
-	var/dismantle_cooldown = 0
-
-/datum/excited_group/New()
-	SSair.excited_groups += src
-
-/datum/excited_group/proc/add_turf(turf/open/T)
-	turf_list += T
-	T.excited_group = src
-	reset_cooldowns()
-
-/datum/excited_group/proc/merge_groups(datum/excited_group/E)
-	if(turf_list.len > E.turf_list.len)
-		SSair.excited_groups -= E
-		for(var/t in E.turf_list)
-			var/turf/open/T = t
-			T.excited_group = src
-			turf_list += T
-		reset_cooldowns()
-	else
-		SSair.excited_groups -= src
-		for(var/t in turf_list)
-			var/turf/open/T = t
-			T.excited_group = E
-			E.turf_list += T
-		E.reset_cooldowns()
-
-/datum/excited_group/proc/reset_cooldowns()
-	breakdown_cooldown = 0
-	dismantle_cooldown = 0
-
-//argument is so world start can clear out any turf differences quickly.
-/datum/excited_group/proc/self_breakdown(space_is_all_consuming = FALSE)
-	var/datum/gas_mixture/A = new
-
-	//make local for sanic speed
-	var/list/A_gases = A.gases
-	var/list/turf_list = src.turf_list
-	var/turflen = turf_list.len
-	var/space_in_group = FALSE
-
-	for(var/t in turf_list)
-		var/turf/open/T = t
-		if (space_is_all_consuming && !space_in_group && istype(T.air, /datum/gas_mixture/immutable/space))
-			space_in_group = TRUE
-			qdel(A)
-			A = new /datum/gas_mixture/immutable/space()
-			A_gases = A.gases //update the cache
-			break
-		A.merge(T.air)
-
-	for(var/id in A_gases)
-		A_gases[id] /= turflen
-
-	for(var/t in turf_list)
-		var/turf/open/T = t
-		T.air.copy_from(A)
-		T.atmos_cooldown = 0
-		T.update_visuals()
-
-	breakdown_cooldown = 0
-
-/datum/excited_group/proc/dismantle()
-	for(var/t in turf_list)
-		var/turf/open/T = t
-		T.excited = FALSE
-		T.excited_group = null
-		SSair.active_turfs -= T
-	garbage_collect()
-
-/datum/excited_group/proc/garbage_collect()
-	for(var/t in turf_list)
-		var/turf/open/T = t
-		T.excited_group = null
-	turf_list.Cut()
-	SSair.excited_groups -= src
 
 ////////////////////////SUPERCONDUCTIVITY/////////////////////////////
-/atom/movable/proc/blocksTemperature()
-	return FALSE
-
 /turf/proc/conductivity_directions()
 	if(archived_cycle < SSair.times_fired)
 		archive()
@@ -376,9 +247,6 @@
 			. |= direction
 
 /turf/proc/neighbor_conduct_with_src(turf/open/other)
-	for (var/atom/movable/G in src)
-		if (G.blocksTemperature())
-			return
 	if(!other.blocks_air) //Open but neighbor is solid
 		other.temperature_share_open_to_solid(src)
 	else //Both tiles are solid
@@ -389,9 +257,7 @@
 	if(blocks_air)
 		..()
 		return
-	for (var/atom/movable/G in src)
+
-		if (G.blocksTemperature())
-			return
 	if(!other.blocks_air) //Both tiles are open
 		var/turf/open/T = other
 		T.air.temperature_share(air, WINDOW_HEAT_TRANSFER_COEFFICIENT)
@@ -410,8 +276,10 @@
 
 				if(!neighbor.thermal_conductivity)
 					continue
+
 				if(neighbor.archived_cycle < SSair.times_fired)
 					neighbor.archive()
+
 				neighbor.neighbor_conduct_with_src(src)
 
 				neighbor.consider_superconductivity()
@@ -430,7 +298,7 @@
 	//Conduct with air on my tile if I have it
 	if(!blocks_air)
 		temperature = air.temperature_share(null, thermal_conductivity, temperature, heat_capacity)
-	..((blocks_air ? temperature : air.temperature))
+	..((blocks_air ? temperature : air.return_temperature()))
 
 /turf/proc/consider_superconductivity()
 	if(!thermal_conductivity)
@@ -440,7 +308,7 @@
 	return TRUE
 
 /turf/open/consider_superconductivity(starting)
-	if(air.temperature < (starting?MINIMUM_TEMPERATURE_START_SUPERCONDUCTION:MINIMUM_TEMPERATURE_FOR_SUPERCONDUCTION))
+	if(air.return_temperature() < (starting?MINIMUM_TEMPERATURE_START_SUPERCONDUCTION:MINIMUM_TEMPERATURE_FOR_SUPERCONDUCTION))
 		return FALSE
 	if(air.heat_capacity() < M_CELL_WITH_RATIO) // Was: MOLES_CELLSTANDARD*0.1*0.05 Since there are no variables here we can make this a constant.
 		return FALSE

code/modules/atmospherics/gasmixtures/gas_mixture.dm

@@ -16,90 +16,80 @@ GLOBAL_LIST_INIT(meta_gas_dangers, meta_gas_danger_list())
 GLOBAL_LIST_INIT(meta_gas_ids, meta_gas_id_list())
 GLOBAL_LIST_INIT(meta_gas_fusions, meta_gas_fusion_list())
 /datum/gas_mixture
-	var/list/gases = list()
+	var/initial_volume = CELL_VOLUME //liters
-	var/list/gas_archive = list()
+	var/list/reaction_results
-	var/temperature = 0 //kelvins
-	var/tmp/temperature_archived = 0
-	var/volume = CELL_VOLUME //liters
-	var/last_share = 0
-	var/list/reaction_results = list()
 	var/list/analyzer_results //used for analyzer feedback - not initialized until its used
-	var/gc_share = FALSE // Whether to call garbage_collect() on the sharer during shares, used for immutable mixtures
+	var/_extools_pointer_gasmixture = 0 // Contains the memory address of the shared_ptr object for this gas mixture in c++ land. Don't. Touch. This. Var.
 
 /datum/gas_mixture/New(volume)
 	if (!isnull(volume))
-		src.volume = volume
+		initial_volume = volume
+	ATMOS_EXTOOLS_CHECK
+	__gasmixture_register()
+	reaction_results = new
 
-	//PV = nRT
+/datum/gas_mixture/vv_edit_var(var_name, var_value)
+	if(var_name == "_extools_pointer_gasmixture")
+		return FALSE // please no. segfaults bad.
+	return ..()
+/*
+/datum/gas_mixture/Del()
+	__gasmixture_unregister()
+	. = ..()*/
 
-/datum/gas_mixture/proc/heat_capacity()
+/datum/gas_mixture/proc/__gasmixture_unregister()
+/datum/gas_mixture/proc/__gasmixture_register()
 
-/datum/gas_mixture/proc/archived_heat_capacity()
+/proc/gas_types()
+	var/list/L = subtypesof(/datum/gas)
+	for(var/gt in L)
+		var/datum/gas/G = gt
+		L[gt] = initial(G.specific_heat)
+	return L
 
-/datum/gas_mixture/heat_capacity() //joules per kelvin
+/datum/gas_mixture/proc/heat_capacity() //joules per kelvin
-	var/list/cached_gases = gases
-	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
-	. = 0
-	for(var/id in cached_gases)
-		. += cached_gases[id] * cached_gasheats[id]
-
-/datum/gas_mixture/archived_heat_capacity()
-	// lots of copypasta but heat_capacity is the single proc called the most in a regular round, bar none, so performance loss adds up
-	var/list/cached_gases = gas_archive
-	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
-	. = 0
-	for(var/id in cached_gases)
-		. += cached_gases[id] * cached_gasheats[id]
-
-/datum/gas_mixture/turf/heat_capacity() // Same as above except vacuums return HEAT_CAPACITY_VACUUM
-	var/list/cached_gases = gases
-	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
-	for(var/id in cached_gases)
-		. += cached_gases[id] * cached_gasheats[id]
-	if(!.)
-		. += HEAT_CAPACITY_VACUUM //we want vacuums in turfs to have the same heat capacity as space
-
-/datum/gas_mixture/turf/archived_heat_capacity() // Same as above except vacuums return HEAT_CAPACITY_VACUUM
-	var/list/cached_gases = gas_archive
-	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
-	for(var/id in cached_gases)
-		. += cached_gases[id] * cached_gasheats[id]
-	if(!.)
-		. += HEAT_CAPACITY_VACUUM //we want vacuums in turfs to have the same heat capacity as space
 
 /datum/gas_mixture/proc/total_moles()
-	var/cached_gases = gases
-	TOTAL_MOLES(cached_gases, .)
 
 /datum/gas_mixture/proc/return_pressure() //kilopascals
-	if(volume > 0) // to prevent division by zero
-		var/cached_gases = gases
-		TOTAL_MOLES(cached_gases, .)
-		. *= R_IDEAL_GAS_EQUATION * temperature / volume
-		return
-	return 0
 
 /datum/gas_mixture/proc/return_temperature() //kelvins
-	return temperature
+
+/datum/gas_mixture/proc/set_min_heat_capacity(n)
+/datum/gas_mixture/proc/set_temperature(new_temp)
+/datum/gas_mixture/proc/set_volume(new_volume)
+/datum/gas_mixture/proc/get_moles(gas_type)
+/datum/gas_mixture/proc/set_moles(gas_type, moles)
+/datum/gas_mixture/proc/scrub_into(datum/gas_mixture/target, list/gases)
+/datum/gas_mixture/proc/mark_immutable()
+/datum/gas_mixture/proc/get_gases()
+/datum/gas_mixture/proc/multiply(factor)
+/datum/gas_mixture/proc/get_last_share()
+/datum/gas_mixture/proc/clear()
+
+/datum/gas_mixture/proc/adjust_moles(gas_type, amt = 0)
+	set_moles(gas_type, get_moles(gas_type) + amt)
 
 /datum/gas_mixture/proc/return_volume() //liters
-	return max(0, volume)
 
 /datum/gas_mixture/proc/thermal_energy() //joules
-	return THERMAL_ENERGY(src) //see code/__DEFINES/atmospherics.dm; use the define in performance critical areas
 
 /datum/gas_mixture/proc/archive()
 	//Update archived versions of variables
 	//Returns: 1 in all cases
 
 /datum/gas_mixture/proc/merge(datum/gas_mixture/giver)
-	//Merges all air from giver into self. Deletes giver.
+	//Merges all air from giver into self. giver is untouched.
 	//Returns: 1 if we are mutable, 0 otherwise
 
 /datum/gas_mixture/proc/remove(amount)
-	//Proportionally removes amount of gas from the gas_mixture
+	//Removes amount of gas from the gas_mixture
 	//Returns: gas_mixture with the gases removed
 
+/datum/gas_mixture/proc/transfer_to(datum/gas_mixture/target, amount)
+	//Transfers amount of gas to target. Equivalent to target.merge(remove(amount)) but faster.
+	//Removes amount of gas from the gas_mixture
+
 /datum/gas_mixture/proc/remove_ratio(ratio)
 	//Proportionally removes amount of gas from the gas_mixture
 	//Returns: gas_mixture with the gases removed
@@ -136,245 +126,63 @@ GLOBAL_LIST_INIT(meta_gas_fusions, meta_gas_fusion_list())
 	//Performs various reactions such as combustion or fusion (LOL)
 	//Returns: 1 if any reaction took place; 0 otherwise
 
-/datum/gas_mixture/archive()
+/datum/gas_mixture/proc/__remove()
-	temperature_archived = temperature
-	gas_archive = gases.Copy()
-	return 1
-
-/datum/gas_mixture/merge(datum/gas_mixture/giver)
-	if(!giver)
-		return 0
-
-	//heat transfer
-	if(abs(temperature - giver.temperature) > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
-		var/self_heat_capacity = heat_capacity()
-		var/giver_heat_capacity = giver.heat_capacity()
-		var/combined_heat_capacity = giver_heat_capacity + self_heat_capacity
-		if(combined_heat_capacity)
-			temperature = (giver.temperature * giver_heat_capacity + temperature * self_heat_capacity) / combined_heat_capacity
-
-	var/list/cached_gases = gases //accessing datum vars is slower than proc vars
-	var/list/giver_gases = giver.gases
-	//gas transfer
-	for(var/giver_id in giver_gases)
-		cached_gases[giver_id] += giver_gases[giver_id]
-
-	return 1
-
 /datum/gas_mixture/remove(amount)
-	var/sum
-	var/list/cached_gases = gases
-	TOTAL_MOLES(cached_gases, sum)
-	amount = min(amount, sum) //Can not take more air than tile has!
-	if(amount <= 0)
-		return null
 	var/datum/gas_mixture/removed = new type
-	var/list/removed_gases = removed.gases //accessing datum vars is slower than proc vars
+	__remove(removed, amount)
-
-	removed.temperature = temperature
-	for(var/id in cached_gases)
-		removed_gases[id] = QUANTIZE((cached_gases[id] / sum) * amount)
-		cached_gases[id] -= removed_gases[id]
-	GAS_GARBAGE_COLLECT(gases)
 
 	return removed
 
+/datum/gas_mixture/proc/__remove_ratio()
 /datum/gas_mixture/remove_ratio(ratio)
-	if(ratio <= 0)
-		return null
-	ratio = min(ratio, 1)
-
-	var/list/cached_gases = gases
 	var/datum/gas_mixture/removed = new type
-	var/list/removed_gases = removed.gases //accessing datum vars is slower than proc vars
+	__remove_ratio(removed, ratio)
-
-	removed.temperature = temperature
-	for(var/id in cached_gases)
-		removed_gases[id] = QUANTIZE(cached_gases[id] * ratio)
-		cached_gases[id] -= removed_gases[id]
-
-	GAS_GARBAGE_COLLECT(gases)
 
 	return removed
 
 /datum/gas_mixture/copy()
-	var/list/cached_gases = gases
 	var/datum/gas_mixture/copy = new type
-	var/list/copy_gases = copy.gases
+	copy.copy_from(src)
-
-	copy.temperature = temperature
-	for(var/id in cached_gases)
-		copy_gases[id] = cached_gases[id]
 
 	return copy
 
-
-/datum/gas_mixture/copy_from(datum/gas_mixture/sample)
-	var/list/cached_gases = gases //accessing datum vars is slower than proc vars
-	var/list/sample_gases = sample.gases
-
-	temperature = sample.temperature
-	for(var/id in sample_gases)
-		cached_gases[id] = sample_gases[id]
-
-	//remove all gases not in the sample
-	cached_gases &= sample_gases
-
-	return 1
-
 /datum/gas_mixture/copy_from_turf(turf/model)
 	parse_gas_string(model.initial_gas_mix)
 
 	//acounts for changes in temperature
 	var/turf/model_parent = model.parent_type
 	if(model.temperature != initial(model.temperature) || model.temperature != initial(model_parent.temperature))
-		temperature = model.temperature
+		set_temperature(model.temperature)
 
 	return 1
 
 /datum/gas_mixture/parse_gas_string(gas_string)
-	var/list/gases = src.gases
 	var/list/gas = params2list(gas_string)
 	if(gas["TEMP"])
-		temperature = text2num(gas["TEMP"])
+		set_temperature(text2num(gas["TEMP"]))
 		gas -= "TEMP"
-	gases.Cut()
+	clear()
 	for(var/id in gas)
 		var/path = id
 		if(!ispath(path))
 			path = gas_id2path(path) //a lot of these strings can't have embedded expressions (especially for mappers), so support for IDs needs to stick around
-		gases[path] = text2num(gas[id])
+		set_moles(path, text2num(gas[id]))
 	archive()
 	return 1
 	
-/datum/gas_mixture/share(datum/gas_mixture/sharer, atmos_adjacent_turfs = 4)
-
-	var/list/cached_gases = gases
-	var/list/sharer_gases = sharer.gases
-
-	var/temperature_delta = temperature_archived - sharer.temperature_archived
-	var/abs_temperature_delta = abs(temperature_delta)
-
-	var/old_self_heat_capacity = 0
-	var/old_sharer_heat_capacity = 0
-	if(abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
-		old_self_heat_capacity = heat_capacity()
-		old_sharer_heat_capacity = sharer.heat_capacity()
-
-	var/heat_capacity_self_to_sharer = 0 //heat capacity of the moles transferred from us to the sharer
-	var/heat_capacity_sharer_to_self = 0 //heat capacity of the moles transferred from the sharer to us
-
-	var/moved_moles = 0
-	var/abs_moved_moles = 0
-
-	//we're gonna define these vars outside of this for loop because as it turns out, var declaration is pricy
-	var/delta
-	var/gas_heat_capacity
-	//and also cache this shit rq because that results in sanic speed for reasons byond explanation
-	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
-	//GAS TRANSFER
-	for(var/id in cached_gases | sharer_gases) // transfer gases
-
-		delta = QUANTIZE(gas_archive[id] - sharer.gas_archive[id])/(atmos_adjacent_turfs+1) //the amount of gas that gets moved between the mixtures
-
-		if(delta && abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
-			gas_heat_capacity = delta * cached_gasheats[id]
-			if(delta > 0)
-				heat_capacity_self_to_sharer += gas_heat_capacity
-			else
-				heat_capacity_sharer_to_self -= gas_heat_capacity //subtract here instead of adding the absolute value because we know that delta is negative.
-
-		cached_gases[id]					-= delta
-		sharer_gases[id]			+= delta
-		moved_moles			+= delta
-		abs_moved_moles		+= abs(delta)
-
-	last_share = abs_moved_moles
-
-	//THERMAL ENERGY TRANSFER
-	if(abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
-		var/new_self_heat_capacity = old_self_heat_capacity + heat_capacity_sharer_to_self - heat_capacity_self_to_sharer
-		var/new_sharer_heat_capacity = old_sharer_heat_capacity + heat_capacity_self_to_sharer - heat_capacity_sharer_to_self
-
-		//transfer of thermal energy (via changed heat capacity) between self and sharer
-		if(new_self_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			temperature = (old_self_heat_capacity*temperature - heat_capacity_self_to_sharer*temperature_archived + heat_capacity_sharer_to_self*sharer.temperature_archived)/new_self_heat_capacity
-
-		if(new_sharer_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			sharer.temperature = (old_sharer_heat_capacity*sharer.temperature-heat_capacity_sharer_to_self*sharer.temperature_archived + heat_capacity_self_to_sharer*temperature_archived)/new_sharer_heat_capacity
-		//thermal energy of the system (self and sharer) is unchanged
-
-			if(abs(old_sharer_heat_capacity) > MINIMUM_HEAT_CAPACITY)
-				if(abs(new_sharer_heat_capacity/old_sharer_heat_capacity - 1) < 0.1) // <10% change in sharer heat capacity
-					temperature_share(sharer, OPEN_HEAT_TRANSFER_COEFFICIENT)
-
-	if (initial(sharer.gc_share))
-		GAS_GARBAGE_COLLECT(sharer.gases)
-	if(temperature_delta > MINIMUM_TEMPERATURE_TO_MOVE || abs(moved_moles) > MINIMUM_MOLES_DELTA_TO_MOVE)
-		var/our_moles
-		TOTAL_MOLES(cached_gases,our_moles)
-		var/their_moles
-		TOTAL_MOLES(sharer_gases,their_moles)
-		return (temperature_archived*(our_moles + moved_moles) - sharer.temperature_archived*(their_moles - moved_moles)) * R_IDEAL_GAS_EQUATION / volume
-
-/datum/gas_mixture/temperature_share(datum/gas_mixture/sharer, conduction_coefficient, sharer_temperature, sharer_heat_capacity)
-	//transfer of thermal energy (via conduction) between self and sharer
-	if(sharer)
-		sharer_temperature = sharer.temperature_archived
-	var/temperature_delta = temperature_archived - sharer_temperature
-	if(abs(temperature_delta) > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
-		var/self_heat_capacity = archived_heat_capacity()
-		sharer_heat_capacity = sharer_heat_capacity || sharer.archived_heat_capacity()
-
-		if((sharer_heat_capacity > MINIMUM_HEAT_CAPACITY) && (self_heat_capacity > MINIMUM_HEAT_CAPACITY))
-			var/heat = conduction_coefficient*temperature_delta* \
-				(self_heat_capacity*sharer_heat_capacity/(self_heat_capacity+sharer_heat_capacity))
-
-			temperature = max(temperature - heat/self_heat_capacity, TCMB)
-			sharer_temperature = max(sharer_temperature + heat/sharer_heat_capacity, TCMB)
-			if(sharer)
-				sharer.temperature = sharer_temperature
-	return sharer_temperature
-	//thermal energy of the system (self and sharer) is unchanged
-
-/datum/gas_mixture/compare(datum/gas_mixture/sample)
-	var/list/sample_gases = sample.gases //accessing datum vars is slower than proc vars
-	var/list/cached_gases = gases
-
-	for(var/id in cached_gases | sample_gases) // compare gases from either mixture
-		var/gas_moles = cached_gases[id]
-		var/sample_moles = sample_gases[id]
-		var/delta = abs(gas_moles - sample_moles)
-		if(delta > MINIMUM_MOLES_DELTA_TO_MOVE && \
-			delta > gas_moles * MINIMUM_AIR_RATIO_TO_MOVE)
-			return id
-
-	var/our_moles
-	TOTAL_MOLES(cached_gases, our_moles)
-	if(our_moles > MINIMUM_MOLES_DELTA_TO_MOVE)
-		var/temp = temperature
-		var/sample_temp = sample.temperature
-
-		var/temperature_delta = abs(temp - sample_temp)
-		if(temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_SUSPEND)
-			return "temp"
-
-	return ""
-
 /datum/gas_mixture/react(datum/holder)
 	. = NO_REACTION
-	var/list/cached_gases = gases
+	if(!total_moles())
-	if(!length(cached_gases))
 		return
 	var/list/reactions = list()
 	for(var/datum/gas_reaction/G in SSair.gas_reactions)
-		if(cached_gases[G.major_gas])
+		if(get_moles(G.major_gas))
 			reactions += G
 	if(!length(reactions))
 		return
 	reaction_results = new
-	var/temp = temperature
+	var/temp = return_temperature()
-	var/ener = THERMAL_ENERGY(src)
+	var/ener = thermal_energy()
 
 	reaction_loop:
 		for(var/r in reactions)
@@ -388,14 +196,13 @@ GLOBAL_LIST_INIT(meta_gas_fusions, meta_gas_fusion_list())
 			for(var/id in min_reqs)
 				if (id == "TEMP" || id == "ENER")
 					continue
-				if(cached_gases[id] < min_reqs[id])
+				if(get_moles(id) < min_reqs[id])
 					continue reaction_loop
 			//at this point, all minimum requirements for the reaction are satisfied.
 
 			/*	currently no reactions have maximum requirements, so we can leave the checks commented out for a slight performance boost
 				PLEASE DO NOT REMOVE THIS CODE. the commenting is here only for a performance increase.
 				enabling these checks should be as easy as possible and the fact that they are disabled should be as clear as possible
-
 			var/list/max_reqs = reaction.max_requirements
 			if((max_reqs["TEMP"] && temp > max_reqs["TEMP"]) \
 			|| (max_reqs["ENER"] && ener > max_reqs["ENER"]))
@@ -410,8 +217,6 @@ GLOBAL_LIST_INIT(meta_gas_fusions, meta_gas_fusion_list())
 			. |= reaction.react(src, holder)
 			if (. & STOP_REACTIONS)
 				break
-	if(.)
-		GAS_GARBAGE_COLLECT(gases)
 
 //Takes the amount of the gas you want to PP as an argument
 //So I don't have to do some hacky switches/defines/magic strings
@@ -420,16 +225,50 @@ GLOBAL_LIST_INIT(meta_gas_fusions, meta_gas_fusion_list())
 //O2_PP = get_partial_pressure(gas_mixture.oxygen)
 
 /datum/gas_mixture/proc/get_breath_partial_pressure(gas_pressure)
-	return (gas_pressure * R_IDEAL_GAS_EQUATION * temperature) / BREATH_VOLUME
+	return (gas_pressure * R_IDEAL_GAS_EQUATION * return_temperature()) / BREATH_VOLUME
 //inverse
 /datum/gas_mixture/proc/get_true_breath_pressure(partial_pressure)
-	return (partial_pressure * BREATH_VOLUME) / (R_IDEAL_GAS_EQUATION * temperature)
+	return (partial_pressure * BREATH_VOLUME) / (R_IDEAL_GAS_EQUATION * return_temperature())
 
 //Mathematical proofs:
 /*
 get_breath_partial_pressure(gas_pp) --> gas_pp/total_moles()*breath_pp = pp
 get_true_breath_pressure(pp) --> gas_pp = pp/breath_pp*total_moles()
-
 10/20*5 = 2.5
 10 = 2.5/5*20
 */
+
+/datum/gas_mixture/turf
+
+/*
+/mob/verb/profile_atmos()
+	/world{loop_checks = 0;}
+	var/datum/gas_mixture/A = new
+	var/datum/gas_mixture/B = new
+	A.parse_gas_string("o2=200;n2=800;TEMP=50")
+	B.parse_gas_string("co2=500;plasma=500;TEMP=5000")
+	var/pa
+	var/pb
+	pa = world.tick_usage
+	for(var/I in 1 to 100000)
+		B.transfer_to(A, 1)
+		A.transfer_to(B, 1)
+	pb = world.tick_usage
+	var/total_time = (pb-pa) * world.tick_lag
+	to_chat(src, "Total time (gas transfer): [total_time]ms")
+	to_chat(src, "Operations per second: [100000 / (total_time/1000)]")
+	pa = world.tick_usage
+	for(var/I in 1 to 100000)
+		B.total_moles();
+	pb = world.tick_usage
+	total_time = (pb-pa) * world.tick_lag
+	to_chat(src, "Total time (total_moles): [total_time]ms")
+	to_chat(src, "Operations per second: [100000 / (total_time/1000)]")
+	pa = world.tick_usage
+	for(var/I in 1 to 100000)
+		new /datum/gas_mixture
+	pb = world.tick_usage
+	total_time = (pb-pa) * world.tick_lag
+	to_chat(src, "Total time (new gas mixture): [total_time]ms")
+	to_chat(src, "Operations per second: [100000 / (total_time/1000)]")
+*/

code/modules/atmospherics/gasmixtures/immutable_mixtures.dm

@@ -2,73 +2,29 @@
 //it can be changed, but any changes will ultimately be undone before they can have any effect
 
 /datum/gas_mixture/immutable
-	var/initial_temperature
+	var/initial_temperature = 0
-	gc_share = TRUE
 
 /datum/gas_mixture/immutable/New()
 	..()
-	temperature = initial_temperature
+	set_temperature(initial_temperature)
-	temperature_archived = initial_temperature
+	populate()
-	gases.Cut()
+	mark_immutable()
 
-/datum/gas_mixture/immutable/merge()
+/datum/gas_mixture/immutable/proc/populate()
-	return 0 //we're immutable.
+	return
 
-/datum/gas_mixture/immutable/share(datum/gas_mixture/sharer, atmos_adjacent_turfs = 4)
-	. = ..(sharer, 0)
-	temperature = initial_temperature
-	temperature_archived = initial_temperature
-	gases.Cut()
-
-/datum/gas_mixture/immutable/react()
-	return 0 //we're immutable.
-
-/datum/gas_mixture/immutable/copy()
-	return new type //we're immutable, so we can just return a new instance.
-
-/datum/gas_mixture/immutable/copy_from()
-	return 0 //we're immutable.
-
-/datum/gas_mixture/immutable/copy_from_turf()
-	return 0 //we're immutable.
-
-/datum/gas_mixture/immutable/parse_gas_string()
-	return 0 //we're immutable.
-
-/datum/gas_mixture/immutable/temperature_share(datum/gas_mixture/sharer, conduction_coefficient, sharer_temperature, sharer_heat_capacity)
-	. = ..()
-	temperature = initial_temperature
-
-/datum/gas_mixture/immutable/proc/after_process_cell()
-	temperature = initial_temperature
-	temperature_archived = initial_temperature
-	gases.Cut()
 
 //used by space tiles
 /datum/gas_mixture/immutable/space
 	initial_temperature = TCMB
 
-/datum/gas_mixture/immutable/space/heat_capacity()
+/datum/gas_mixture/immutable/space/populate()
-	return HEAT_CAPACITY_VACUUM
+	set_min_heat_capacity(HEAT_CAPACITY_VACUUM)
-
-/datum/gas_mixture/immutable/space/remove()
-	return copy() //we're always empty, so we can just return a copy.
-
-/datum/gas_mixture/immutable/space/remove_ratio()
-	return copy() //we're always empty, so we can just return a copy.
-
 
 //used by cloners
 /datum/gas_mixture/immutable/cloner
 	initial_temperature = T20C
 
-/datum/gas_mixture/immutable/cloner/New()
+/datum/gas_mixture/immutable/cloner/populate()
 	..()
-	gases[/datum/gas/nitrogen] = MOLES_O2STANDARD + MOLES_N2STANDARD
+	set_moles(/datum/gas/nitrogen, MOLES_O2STANDARD + MOLES_N2STANDARD)
-
-/datum/gas_mixture/immutable/cloner/share(datum/gas_mixture/sharer, atmos_adjacent_turfs = 4)
-	. = ..(sharer, 0)
-	gases[/datum/gas/nitrogen] = MOLES_O2STANDARD + MOLES_N2STANDARD
-
-/datum/gas_mixture/immutable/cloner/heat_capacity()
-	return (MOLES_O2STANDARD + MOLES_N2STANDARD)*20 //specific heat of nitrogen is 20

code/modules/atmospherics/gasmixtures/reactions.dm

@@ -63,11 +63,11 @@
 /datum/gas_reaction/water_vapor/react(datum/gas_mixture/air, datum/holder)
 	var/turf/open/location = isturf(holder) ? holder : null
 	. = NO_REACTION
-	if (air.temperature <= WATER_VAPOR_FREEZE)
+	if (air.return_temperature() <= WATER_VAPOR_FREEZE)
 		if(location && location.freon_gas_act())
 			. = REACTING
 	else if(location && location.water_vapor_gas_act())
-		air.gases[/datum/gas/water_vapor] -= MOLES_GAS_VISIBLE
+		air.adjust_moles(/datum/gas/water_vapor,-MOLES_GAS_VISIBLE)
 		. = REACTING
 
 //tritium combustion: combustion of oxygen and tritium (treated as hydrocarbons). creates hotspots. exothermic
@@ -86,38 +86,37 @@
 /datum/gas_reaction/tritfire/react(datum/gas_mixture/air, datum/holder)
 	var/energy_released = 0
 	var/old_heat_capacity = air.heat_capacity()
-	var/list/cached_gases = air.gases //this speeds things up because accessing datum vars is slow
+	var/temperature = air.return_temperature()
-	var/temperature = air.temperature
 	var/list/cached_results = air.reaction_results
 	cached_results["fire"] = 0
 	var/turf/open/location = isturf(holder) ? holder : null
 
 	var/burned_fuel = 0
-	if(cached_gases[/datum/gas/oxygen] < cached_gases[/datum/gas/tritium])
+	if(air.get_moles(/datum/gas/oxygen) < air.get_moles(/datum/gas/tritium))
-		burned_fuel = cached_gases[/datum/gas/oxygen]/TRITIUM_BURN_OXY_FACTOR
+		burned_fuel = air.get_moles(/datum/gas/oxygen)/TRITIUM_BURN_OXY_FACTOR
-		cached_gases[/datum/gas/tritium] -= burned_fuel
+		air.adjust_moles(/datum/gas/tritium, -burned_fuel)
 	else
-		burned_fuel = cached_gases[/datum/gas/tritium]*TRITIUM_BURN_TRIT_FACTOR
+		burned_fuel = air.get_moles(/datum/gas/tritium)*TRITIUM_BURN_TRIT_FACTOR
-		cached_gases[/datum/gas/tritium] -= cached_gases[/datum/gas/tritium]/TRITIUM_BURN_TRIT_FACTOR
+		air.adjust_moles(/datum/gas/tritium, -air.get_moles(/datum/gas/tritium)/TRITIUM_BURN_TRIT_FACTOR)
-		cached_gases[/datum/gas/oxygen] -= cached_gases[/datum/gas/tritium]
+		air.adjust_moles(/datum/gas/oxygen,-air.get_moles(/datum/gas/tritium))
 
 	if(burned_fuel)
 		energy_released += (FIRE_HYDROGEN_ENERGY_RELEASED * burned_fuel)
 		if(location && prob(10) && burned_fuel > TRITIUM_MINIMUM_RADIATION_ENERGY) //woah there let's not crash the server
 			radiation_pulse(location, energy_released/TRITIUM_BURN_RADIOACTIVITY_FACTOR)
 
-		cached_gases[/datum/gas/water_vapor] += burned_fuel/TRITIUM_BURN_OXY_FACTOR
+		air.adjust_moles(/datum/gas/water_vapor, burned_fuel/TRITIUM_BURN_OXY_FACTOR)
 
 		cached_results["fire"] += burned_fuel
 
 	if(energy_released > 0)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = (temperature*old_heat_capacity + energy_released)/new_heat_capacity
+			air.set_temperature((temperature*old_heat_capacity + energy_released)/new_heat_capacity)
 
 	//let the floor know a fire is happening
 	if(istype(location))
-		temperature = air.temperature
+		temperature = air.return_temperature()
 		if(temperature > FIRE_MINIMUM_TEMPERATURE_TO_EXIST)
 			location.hotspot_expose(temperature, CELL_VOLUME)
 			for(var/I in location)
@@ -143,8 +142,7 @@
 /datum/gas_reaction/plasmafire/react(datum/gas_mixture/air, datum/holder)
 	var/energy_released = 0
 	var/old_heat_capacity = air.heat_capacity()
-	var/list/cached_gases = air.gases //this speeds things up because accessing datum vars is slow
+	var/temperature = air.return_temperature()
-	var/temperature = air.temperature
 	var/list/cached_results = air.reaction_results
 	cached_results["fire"] = 0
 	var/turf/open/location = isturf(holder) ? holder : null
@@ -163,21 +161,21 @@
 		temperature_scale = (temperature-PLASMA_MINIMUM_BURN_TEMPERATURE)/(PLASMA_UPPER_TEMPERATURE-PLASMA_MINIMUM_BURN_TEMPERATURE)
 	if(temperature_scale > 0)
 		oxygen_burn_rate = OXYGEN_BURN_RATE_BASE - temperature_scale
-		if(cached_gases[/datum/gas/oxygen] / cached_gases[/datum/gas/plasma] > SUPER_SATURATION_THRESHOLD) //supersaturation. Form Tritium.
+		if(air.get_moles(/datum/gas/oxygen) / air.get_moles(/datum/gas/plasma) > SUPER_SATURATION_THRESHOLD) //supersaturation. Form Tritium.
 			super_saturation = TRUE
-		if(cached_gases[/datum/gas/oxygen] > cached_gases[/datum/gas/plasma]*PLASMA_OXYGEN_FULLBURN)
+		if(air.get_moles(/datum/gas/oxygen) > air.get_moles(/datum/gas/plasma)*PLASMA_OXYGEN_FULLBURN)
-			plasma_burn_rate = (cached_gases[/datum/gas/plasma]*temperature_scale)/PLASMA_BURN_RATE_DELTA
+			plasma_burn_rate = (air.get_moles(/datum/gas/plasma)*temperature_scale)/PLASMA_BURN_RATE_DELTA
 		else
-			plasma_burn_rate = (temperature_scale*(cached_gases[/datum/gas/oxygen]/PLASMA_OXYGEN_FULLBURN))/PLASMA_BURN_RATE_DELTA
+			plasma_burn_rate = (temperature_scale*(air.get_moles(/datum/gas/oxygen)/PLASMA_OXYGEN_FULLBURN))/PLASMA_BURN_RATE_DELTA
 
 		if(plasma_burn_rate > MINIMUM_HEAT_CAPACITY)
-			plasma_burn_rate = min(plasma_burn_rate,cached_gases[/datum/gas/plasma],cached_gases[/datum/gas/oxygen]/oxygen_burn_rate) //Ensures matter is conserved properly
+			plasma_burn_rate = min(plasma_burn_rate,air.get_moles(/datum/gas/plasma),air.get_moles(/datum/gas/oxygen)/oxygen_burn_rate) //Ensures matter is conserved properly
-			cached_gases[/datum/gas/plasma] = QUANTIZE(cached_gases[/datum/gas/plasma] - plasma_burn_rate)
+			air.set_moles(/datum/gas/plasma, QUANTIZE(air.get_moles(/datum/gas/plasma) - plasma_burn_rate))
-			cached_gases[/datum/gas/oxygen] = QUANTIZE(cached_gases[/datum/gas/oxygen] - (plasma_burn_rate * oxygen_burn_rate))
+			air.set_moles(/datum/gas/oxygen, QUANTIZE(air.get_moles(/datum/gas/oxygen) - (plasma_burn_rate * oxygen_burn_rate)))
 			if (super_saturation)
-				cached_gases[/datum/gas/tritium] += plasma_burn_rate
+				air.adjust_moles(/datum/gas/tritium, plasma_burn_rate)
 			else
-				cached_gases[/datum/gas/carbon_dioxide] += plasma_burn_rate
+				air.adjust_moles(/datum/gas/carbon_dioxide, plasma_burn_rate)
 
 			energy_released += FIRE_PLASMA_ENERGY_RELEASED * (plasma_burn_rate)
 
@@ -186,11 +184,11 @@
 	if(energy_released > 0)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = (temperature*old_heat_capacity + energy_released)/new_heat_capacity
+			air.set_temperature((temperature*old_heat_capacity + energy_released)/new_heat_capacity)
 
 	//let the floor know a fire is happening
 	if(istype(location))
-		temperature = air.temperature
+		temperature = air.return_temperature()
 		if(temperature > FIRE_MINIMUM_TEMPERATURE_TO_EXIST)
 			location.hotspot_expose(temperature, CELL_VOLUME)
 			for(var/I in location)
@@ -218,7 +216,6 @@
 		/datum/gas/carbon_dioxide = FUSION_MOLE_THRESHOLD)
 
 /datum/gas_reaction/fusion/react(datum/gas_mixture/air, datum/holder)
-	var/list/cached_gases = air.gases
 	var/turf/open/location
 	if (istype(holder,/datum/pipeline)) //Find the tile the reaction is occuring on, or a random part of the network if it's a pipenet.
 		var/datum/pipeline/fusion_pipenet = holder
@@ -230,14 +227,14 @@
 	var/list/cached_scan_results = air.analyzer_results
 	var/old_heat_capacity = air.heat_capacity()
 	var/reaction_energy = 0 //Reaction energy can be negative or positive, for both exothermic and endothermic reactions.
-	var/initial_plasma = cached_gases[/datum/gas/plasma]
+	var/initial_plasma = air.get_moles(/datum/gas/plasma)
-	var/initial_carbon = cached_gases[/datum/gas/carbon_dioxide]
+	var/initial_carbon = air.get_moles(/datum/gas/carbon_dioxide)
-	var/scale_factor = (air.volume)/(PI) //We scale it down by volume/Pi because for fusion conditions, moles roughly = 2*volume, but we want it to be based off something constant between reactions.
+	var/scale_factor = (air.return_volume())/(PI) //We scale it down by volume/Pi because for fusion conditions, moles roughly = 2*volume, but we want it to be based off something constant between reactions.
-	var/toroidal_size = (2*PI)+TORADIANS(arctan((air.volume-TOROID_VOLUME_BREAKEVEN)/TOROID_VOLUME_BREAKEVEN)) //The size of the phase space hypertorus
+	var/toroidal_size = (2*PI)+TORADIANS(arctan((air.return_volume()-TOROID_VOLUME_BREAKEVEN)/TOROID_VOLUME_BREAKEVEN)) //The size of the phase space hypertorus
 	var/gas_power = 0
 	var/list/gas_fusion_powers = GLOB.meta_gas_fusions
-	for (var/gas_id in cached_gases)
+	for (var/gas_id in air.get_gases())
-		gas_power += (gas_fusion_powers[gas_id]*cached_gases[gas_id])
+		gas_power += (gas_fusion_powers[gas_id]*air.get_moles(gas_id))
 	var/instability = MODULUS((gas_power*INSTABILITY_GAS_POWER_FACTOR)**2,toroidal_size) //Instability effects how chaotic the behavior of the reaction is
 	cached_scan_results[id] = instability//used for analyzer feedback
 
@@ -249,9 +246,9 @@
 	carbon = MODULUS(carbon - plasma, toroidal_size)
 
 
-	cached_gases[/datum/gas/plasma] = plasma*scale_factor + FUSION_MOLE_THRESHOLD //Scales the gases back up
+	air.set_moles(/datum/gas/plasma, plasma*scale_factor + FUSION_MOLE_THRESHOLD) //Scales the gases back up
-	cached_gases[/datum/gas/carbon_dioxide] = carbon*scale_factor + FUSION_MOLE_THRESHOLD
+	air.set_moles(/datum/gas/carbon_dioxide , carbon*scale_factor + FUSION_MOLE_THRESHOLD)
-	var/delta_plasma = initial_plasma - cached_gases[/datum/gas/plasma]
+	var/delta_plasma = initial_plasma - air.get_moles(/datum/gas/plasma)
 
 	reaction_energy += delta_plasma*PLASMA_BINDING_ENERGY //Energy is gained or lost corresponding to the creation or destruction of mass.
 	if(instability < FUSION_INSTABILITY_ENDOTHERMALITY)
@@ -260,17 +257,17 @@
 		reaction_energy *= (instability-FUSION_INSTABILITY_ENDOTHERMALITY)**0.5
 
 	if(air.thermal_energy() + reaction_energy < 0) //No using energy that doesn't exist.
-		cached_gases[/datum/gas/plasma] = initial_plasma
+		air.set_moles(/datum/gas/plasma,initial_plasma)
-		cached_gases[/datum/gas/carbon_dioxide] = initial_carbon
+		air.set_moles(/datum/gas/carbon_dioxide, initial_carbon)
 		return NO_REACTION
-	cached_gases[/datum/gas/tritium] -= FUSION_TRITIUM_MOLES_USED
+	air.adjust_moles(/datum/gas/tritium, -FUSION_TRITIUM_MOLES_USED)
 	//The decay of the tritium and the reaction's energy produces waste gases, different ones depending on whether the reaction is endo or exothermic
 	if(reaction_energy > 0)
-		cached_gases[/datum/gas/oxygen] += FUSION_TRITIUM_MOLES_USED*(reaction_energy*FUSION_TRITIUM_CONVERSION_COEFFICIENT)
+		air.adjust_moles(/datum/gas/oxygen, FUSION_TRITIUM_MOLES_USED*(reaction_energy*FUSION_TRITIUM_CONVERSION_COEFFICIENT))
-		cached_gases[/datum/gas/nitrous_oxide] += FUSION_TRITIUM_MOLES_USED*(reaction_energy*FUSION_TRITIUM_CONVERSION_COEFFICIENT)
+		air.adjust_moles(/datum/gas/nitrous_oxide, FUSION_TRITIUM_MOLES_USED*(reaction_energy*FUSION_TRITIUM_CONVERSION_COEFFICIENT))
 	else
-		cached_gases[/datum/gas/bz] += FUSION_TRITIUM_MOLES_USED*(reaction_energy*-FUSION_TRITIUM_CONVERSION_COEFFICIENT)
+		air.adjust_moles(/datum/gas/bz, FUSION_TRITIUM_MOLES_USED*(reaction_energy*-FUSION_TRITIUM_CONVERSION_COEFFICIENT))
-		cached_gases[/datum/gas/nitryl] += FUSION_TRITIUM_MOLES_USED*(reaction_energy*-FUSION_TRITIUM_CONVERSION_COEFFICIENT)
+		air.adjust_moles(/datum/gas/nitryl, FUSION_TRITIUM_MOLES_USED*(reaction_energy*-FUSION_TRITIUM_CONVERSION_COEFFICIENT))
 
 	if(reaction_energy)
 		if(location)
@@ -282,7 +279,7 @@
 
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = clamp(((air.temperature*old_heat_capacity + reaction_energy)/new_heat_capacity),TCMB,INFINITY)
+			air.set_temperature(clamp(((air.return_temperature()*old_heat_capacity + reaction_energy)/new_heat_capacity),TCMB,INFINITY))
 		return REACTING
 
 /datum/gas_reaction/nitrylformation //The formation of nitryl. Endothermic. Requires N2O as a catalyst.
@@ -299,22 +296,21 @@
 	)
 
 /datum/gas_reaction/nitrylformation/react(datum/gas_mixture/air)
-	var/list/cached_gases = air.gases
+	var/temperature = air.return_temperature()
-	var/temperature = air.temperature
 
 	var/old_heat_capacity = air.heat_capacity()
-	var/heat_efficency = min(temperature/(FIRE_MINIMUM_TEMPERATURE_TO_EXIST*100),cached_gases[/datum/gas/oxygen],cached_gases[/datum/gas/nitrogen])
+	var/heat_efficency = min(temperature/(FIRE_MINIMUM_TEMPERATURE_TO_EXIST*100),air.get_moles(/datum/gas/oxygen),air.get_moles(/datum/gas/nitrogen))
 	var/energy_used = heat_efficency*NITRYL_FORMATION_ENERGY
-	if ((cached_gases[/datum/gas/oxygen] - heat_efficency < 0 )|| (cached_gases[/datum/gas/nitrogen] - heat_efficency < 0)) //Shouldn't produce gas from nothing.
+	if ((air.get_moles(/datum/gas/oxygen) - heat_efficency < 0 )|| (air.get_moles(/datum/gas/nitrogen) - heat_efficency < 0)) //Shouldn't produce gas from nothing.
 		return NO_REACTION
-	cached_gases[/datum/gas/oxygen] -= heat_efficency
+	air.adjust_moles(/datum/gas/oxygen, heat_efficency)
-	cached_gases[/datum/gas/nitrogen] -= heat_efficency
+	air.adjust_moles(/datum/gas/nitrogen, heat_efficency)
-	cached_gases[/datum/gas/nitryl] += heat_efficency*2
+	air.adjust_moles(/datum/gas/nitryl, heat_efficency*2)
 
 	if(energy_used > 0)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = max(((temperature*old_heat_capacity - energy_used)/new_heat_capacity),TCMB)
+			air.set_temperature(max(((temperature*old_heat_capacity - energy_used)/new_heat_capacity),TCMB))
 		return REACTING
 
 /datum/gas_reaction/bzformation //Formation of BZ by combining plasma and tritium at low pressures. Exothermic.
@@ -330,27 +326,26 @@
 
 
 /datum/gas_reaction/bzformation/react(datum/gas_mixture/air)
-	var/list/cached_gases = air.gases
+	var/temperature = air.return_temperature()
-	var/temperature = air.temperature
 	var/pressure = air.return_pressure()
 	var/old_heat_capacity = air.heat_capacity()
-	var/reaction_efficency = min(1/((pressure/(0.1*ONE_ATMOSPHERE))*(max(cached_gases[/datum/gas/plasma]/cached_gases[/datum/gas/nitrous_oxide],1))),cached_gases[/datum/gas/nitrous_oxide],cached_gases[/datum/gas/plasma]/2)
+	var/reaction_efficency = min(1/((pressure/(0.1*ONE_ATMOSPHERE))*(max(air.get_moles(/datum/gas/plasma)/air.get_moles(/datum/gas/nitrous_oxide),1))),air.get_moles(/datum/gas/nitrous_oxide),air.get_moles(/datum/gas/plasma)/2)
 	var/energy_released = 2*reaction_efficency*FIRE_CARBON_ENERGY_RELEASED
-	if ((cached_gases[/datum/gas/nitrous_oxide] - reaction_efficency < 0 )|| (cached_gases[/datum/gas/plasma] - (2*reaction_efficency) < 0) || energy_released <= 0) //Shouldn't produce gas from nothing.
+	if ((air.get_moles(/datum/gas/nitrous_oxide) - reaction_efficency < 0 )|| (air.get_moles(/datum/gas/plasma) - (2*reaction_efficency) < 0) || energy_released <= 0) //Shouldn't produce gas from nothing.
 		return NO_REACTION
-	cached_gases[/datum/gas/bz] += reaction_efficency
+	air.adjust_moles(/datum/gas/bz, reaction_efficency)
-	if(reaction_efficency == cached_gases[/datum/gas/nitrous_oxide])
+	if(reaction_efficency == air.get_moles(/datum/gas/nitrous_oxide))
-		cached_gases[/datum/gas/bz] -= min(pressure,1)
+		air.adjust_moles(/datum/gas/bz, -min(pressure,1))
-		cached_gases[/datum/gas/oxygen] += min(pressure,1)
+		air.adjust_moles(/datum/gas/oxygen, min(pressure,1))
-	cached_gases[/datum/gas/nitrous_oxide] -= reaction_efficency
+	air.adjust_moles(/datum/gas/nitrous_oxide, -reaction_efficency)
-	cached_gases[/datum/gas/plasma]  -= 2*reaction_efficency
+	air.adjust_moles(/datum/gas/plasma, -2*reaction_efficency)
 
 	SSresearch.science_tech.add_point_type(TECHWEB_POINT_TYPE_DEFAULT, min((reaction_efficency**2)*BZ_RESEARCH_SCALE),BZ_RESEARCH_MAX_AMOUNT)
 
 	if(energy_released > 0)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = max(((temperature*old_heat_capacity + energy_released)/new_heat_capacity),TCMB)
+			air.set_temperature(max(((temperature*old_heat_capacity + energy_released)/new_heat_capacity),TCMB))
 		return REACTING
 
 /datum/gas_reaction/stimformation //Stimulum formation follows a strange pattern of how effective it will be at a given temperature, having some multiple peaks and some large dropoffs. Exo and endo thermic.
@@ -367,24 +362,22 @@
 		"TEMP" = STIMULUM_HEAT_SCALE/2)
 
 /datum/gas_reaction/stimformation/react(datum/gas_mixture/air)
-	var/list/cached_gases = air.gases
-
 	var/old_heat_capacity = air.heat_capacity()
-	var/heat_scale = min(air.temperature/STIMULUM_HEAT_SCALE,cached_gases[/datum/gas/tritium],cached_gases[/datum/gas/plasma],cached_gases[/datum/gas/nitryl])
+	var/heat_scale = min(air.return_temperature()/STIMULUM_HEAT_SCALE,air.get_moles(/datum/gas/tritium),air.get_moles(/datum/gas/plasma),air.get_moles(/datum/gas/nitryl))
 	var/stim_energy_change = heat_scale + STIMULUM_FIRST_RISE*(heat_scale**2) - STIMULUM_FIRST_DROP*(heat_scale**3) + STIMULUM_SECOND_RISE*(heat_scale**4) - STIMULUM_ABSOLUTE_DROP*(heat_scale**5)
 
-	if ((cached_gases[/datum/gas/tritium] - heat_scale < 0 )|| (cached_gases[/datum/gas/plasma] - heat_scale < 0) || (cached_gases[/datum/gas/nitryl] - heat_scale < 0)) //Shouldn't produce gas from nothing.
+	if ((air.get_moles(/datum/gas/tritium) - heat_scale < 0 )|| (air.get_moles(/datum/gas/plasma) - heat_scale < 0) || (air.get_moles(/datum/gas/nitryl) - heat_scale < 0)) //Shouldn't produce gas from nothing.
 		return NO_REACTION
-	cached_gases[/datum/gas/stimulum]+= heat_scale/10
+	air.adjust_moles(/datum/gas/stimulum, heat_scale/10)
-	cached_gases[/datum/gas/tritium] -= heat_scale
+	air.adjust_moles(/datum/gas/tritium, -heat_scale)
-	cached_gases[/datum/gas/plasma] -= heat_scale
+	air.adjust_moles(/datum/gas/plasma, -heat_scale)
-	cached_gases[/datum/gas/nitryl] -= heat_scale
+	air.adjust_moles(/datum/gas/nitryl, -heat_scale)
 
 	SSresearch.science_tech.add_point_type(TECHWEB_POINT_TYPE_DEFAULT, STIMULUM_RESEARCH_AMOUNT*max(stim_energy_change,0))
 	if(stim_energy_change)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = max(((air.temperature*old_heat_capacity + stim_energy_change)/new_heat_capacity),TCMB)
+			air.set_temperature(max(((air.return_temperature()*old_heat_capacity + stim_energy_change)/new_heat_capacity),TCMB))
 		return REACTING
 
 /datum/gas_reaction/nobliumformation //Hyper-Noblium formation is extrememly endothermic, but requires high temperatures to start. Due to its high mass, hyper-nobelium uses large amounts of nitrogen and tritium. BZ can be used as a catalyst to make it less endothermic.
@@ -399,22 +392,21 @@
 		"TEMP" = 5000000)
 
 /datum/gas_reaction/nobliumformation/react(datum/gas_mixture/air)
-	var/list/cached_gases = air.gases
 	var/old_heat_capacity = air.heat_capacity()
-	var/nob_formed = min((cached_gases[/datum/gas/nitrogen]+cached_gases[/datum/gas/tritium])/100,cached_gases[/datum/gas/tritium]/10,cached_gases[/datum/gas/nitrogen]/20)
+	var/nob_formed = min((air.get_moles(/datum/gas/nitrogen)+air.get_moles(/datum/gas/tritium))/100,air.get_moles(/datum/gas/tritium)/10,air.get_moles(/datum/gas/nitrogen)/20)
-	var/energy_taken = nob_formed*(NOBLIUM_FORMATION_ENERGY/(max(cached_gases[/datum/gas/bz],1)))
+	var/energy_taken = nob_formed*(NOBLIUM_FORMATION_ENERGY/(max(air.get_moles(/datum/gas/bz),1)))
-	if ((cached_gases[/datum/gas/tritium] - 10*nob_formed < 0) || (cached_gases[/datum/gas/nitrogen] - 20*nob_formed < 0))
+	if ((air.get_moles(/datum/gas/tritium) - 10*nob_formed < 0) || (air.get_moles(/datum/gas/nitrogen) - 20*nob_formed < 0))
 		return NO_REACTION
-	cached_gases[/datum/gas/tritium] -= 10*nob_formed
+	air.adjust_moles(/datum/gas/tritium, -10*nob_formed)
-	cached_gases[/datum/gas/nitrogen] -= 20*nob_formed
+	air.adjust_moles(/datum/gas/nitrogen, -20*nob_formed)
-	cached_gases[/datum/gas/hypernoblium]+= nob_formed
+	air.adjust_moles(/datum/gas/hypernoblium,nob_formed)
 
 	SSresearch.science_tech.add_point_type(TECHWEB_POINT_TYPE_DEFAULT, nob_formed*NOBLIUM_RESEARCH_AMOUNT)
 
 	if (nob_formed)
 		var/new_heat_capacity = air.heat_capacity()
 		if(new_heat_capacity > MINIMUM_HEAT_CAPACITY)
-			air.temperature = max(((air.temperature*old_heat_capacity - energy_taken)/new_heat_capacity),TCMB)
+			air.set_temperature(max(((air.return_temperature()*old_heat_capacity - energy_taken)/new_heat_capacity),TCMB))
 
 
 /datum/gas_reaction/miaster	//dry heat sterilization: clears out pathogens in the air
@@ -429,16 +421,15 @@
 	)
 
 /datum/gas_reaction/miaster/react(datum/gas_mixture/air, datum/holder)
-	var/list/cached_gases = air.gases
 	// As the name says it, it needs to be dry
-	if(cached_gases[/datum/gas/water_vapor] && cached_gases[/datum/gas/water_vapor]/air.total_moles() > 0.1)
+	if(air.get_moles(/datum/gas/water_vapor) && air.get_moles(/datum/gas/water_vapor)/air.total_moles() > 0.1)
 		return
 
 	//Replace miasma with oxygen
-	var/cleaned_air = min(cached_gases[/datum/gas/miasma], 20 + (air.temperature - FIRE_MINIMUM_TEMPERATURE_TO_EXIST - 70) / 20)
+	var/cleaned_air = min(air.get_moles(/datum/gas/miasma), 20 + (air.return_temperature() - FIRE_MINIMUM_TEMPERATURE_TO_EXIST - 70) / 20)
-	cached_gases[/datum/gas/miasma] -= cleaned_air
+	air.adjust_moles(/datum/gas/miasma, -cleaned_air)
-	cached_gases[/datum/gas/oxygen] += cleaned_air
+	air.adjust_moles(/datum/gas/oxygen, cleaned_air)
 
 	//Possibly burning a bit of organic matter through maillard reaction, so a *tiny* bit more heat would be understandable
-	air.temperature += cleaned_air * 0.002
+	air.set_temperature(air.return_temperature() + cleaned_air * 0.002)
 	SSresearch.science_tech.add_point_type(TECHWEB_POINT_TYPE_DEFAULT, cleaned_air*MIASMA_RESEARCH_AMOUNT)//Turns out the burning of miasma is kinda interesting to scientists

code/modules/atmospherics/gasmixtures/zextools_broke.dm

@@ -0,0 +1,304 @@
+#ifdef EXTOOLS_BROKE
+
+/datum/gas_mixture
+	var/list/gases = list()
+	var/temperature = 0 //kelvins
+	var/tmp/temperature_archived = 0
+	var/volume = CELL_VOLUME //liters
+	var/last_share = 0
+
+/datum/gas_mixture/heat_capacity() //joules per kelvin
+	var/list/cached_gases = gases
+	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
+	. = 0
+	for(var/id in cached_gases)
+		. += cached_gases[id] * cached_gasheats[id]
+
+/datum/gas_mixture/turf/heat_capacity() // Same as above except vacuums return HEAT_CAPACITY_VACUUM
+	var/list/cached_gases = gases
+	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
+	for(var/id in cached_gases)
+		. += cached_gases[id] * cached_gasheats[id]
+	if(!.)
+		. += HEAT_CAPACITY_VACUUM //we want vacuums in turfs to have the same heat capacity as space
+
+//prefer this to gas_mixture/total_moles in performance critical areas
+#define TOTAL_MOLES(cached_gases, out_var)\
+	out_var = 0;\
+	for(var/total_moles_id in cached_gases){\
+		out_var += cached_gases[total_moles_id];\
+	}
+
+#define THERMAL_ENERGY(gas) (gas.temperature * gas.heat_capacity())
+
+/datum/gas_mixture/total_moles()
+	var/cached_gases = gases
+	TOTAL_MOLES(cached_gases, .)
+
+/datum/gas_mixture/return_pressure() //kilopascals
+	if(volume > 0) // to prevent division by zero
+		var/cached_gases = gases
+		TOTAL_MOLES(cached_gases, .)
+		. *= R_IDEAL_GAS_EQUATION * temperature / volume
+		return
+	return 0
+
+/datum/gas_mixture/return_temperature() //kelvins
+	return temperature
+
+/datum/gas_mixture/set_min_heat_capacity(n)
+	return
+/datum/gas_mixture/set_temperature(new_temp)
+	temperature = new_temp
+/datum/gas_mixture/set_volume(new_volume)
+	volume = new_volume
+/datum/gas_mixture/get_moles(gas_type)
+	return gases[gas_type]
+/datum/gas_mixture/set_moles(gas_type, moles)
+	gases[gas_type] = moles
+/datum/gas_mixture/scrub_into(datum/gas_mixture/target, list/gases)
+	if(isnull(target))
+		return FALSE
+
+	var/list/removed_gases = target.gases
+
+	//Filter it
+	var/datum/gas_mixture/filtered_out = new
+	var/list/filtered_gases = filtered_out.gases
+	filtered_out.temperature = removed.temperature
+	for(var/gas in filter_types & removed_gases)
+		filtered_gases[gas] = removed_gases[gas]
+		removed_gases[gas] = 0
+	merge(filtered_out)
+/datum/gas_mixture/mark_immutable()
+	return
+/datum/gas_mixture/get_gases()
+	return gases
+/datum/gas_mixture/multiply(factor)
+	for(var/id in gases)
+		gases[id] *= factor
+/datum/gas_mixture/get_last_share()
+	return last_share
+/datum/gas_mixture/clear()
+	gases.Cut()
+
+/datum/gas_mixture/return_volume()
+	return volume // wow!
+
+/datum/gas_mixture/thermal_energy()
+	return THERMAL_ENERGY(src)
+
+/datum/gas_mixture/archive()
+	temperature_archived = temperature
+	gas_archive = gases.Copy()
+	return 1
+
+/datum/gas_mixture/merge(datum/gas_mixture/giver)
+	if(!giver)
+		return 0
+
+	//heat transfer
+	if(abs(temperature - giver.temperature) > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
+		var/self_heat_capacity = heat_capacity()
+		var/giver_heat_capacity = giver.heat_capacity()
+		var/combined_heat_capacity = giver_heat_capacity + self_heat_capacity
+		if(combined_heat_capacity)
+			temperature = (giver.temperature * giver_heat_capacity + temperature * self_heat_capacity) / combined_heat_capacity
+
+	var/list/cached_gases = gases //accessing datum vars is slower than proc vars
+	var/list/giver_gases = giver.gases
+	//gas transfer
+	for(var/giver_id in giver_gases)
+		cached_gases[giver_id] += giver_gases[giver_id]
+
+	return 1
+
+/datum/gas_mixture/remove(amount)
+	var/sum
+	var/list/cached_gases = gases
+	TOTAL_MOLES(cached_gases, sum)
+	amount = min(amount, sum) //Can not take more air than tile has!
+	if(amount <= 0)
+		return null
+	var/datum/gas_mixture/removed = new type
+	var/list/removed_gases = removed.gases //accessing datum vars is slower than proc vars
+
+	removed.temperature = temperature
+	for(var/id in cached_gases)
+		removed_gases[id] = QUANTIZE((cached_gases[id] / sum) * amount)
+		cached_gases[id] -= removed_gases[id]
+	GAS_GARBAGE_COLLECT(gases)
+
+	return removed
+
+/datum/gas_mixture/remove_ratio(ratio)
+	if(ratio <= 0)
+		return null
+	ratio = min(ratio, 1)
+
+	var/list/cached_gases = gases
+	var/datum/gas_mixture/removed = new type
+	var/list/removed_gases = removed.gases //accessing datum vars is slower than proc vars
+
+	removed.temperature = temperature
+	for(var/id in cached_gases)
+		removed_gases[id] = QUANTIZE(cached_gases[id] * ratio)
+		cached_gases[id] -= removed_gases[id]
+
+	GAS_GARBAGE_COLLECT(gases)
+
+	return removed
+
+/datum/gas_mixture/copy()
+	var/list/cached_gases = gases
+	var/datum/gas_mixture/copy = new type
+	var/list/copy_gases = copy.gases
+
+	copy.temperature = temperature
+	for(var/id in cached_gases)
+		copy_gases[id] = cached_gases[id]
+
+	return copy
+
+
+/datum/gas_mixture/copy_from(datum/gas_mixture/sample)
+	var/list/cached_gases = gases //accessing datum vars is slower than proc vars
+	var/list/sample_gases = sample.gases
+
+	temperature = sample.temperature
+	for(var/id in sample_gases)
+		cached_gases[id] = sample_gases[id]
+
+	//remove all gases not in the sample
+	cached_gases &= sample_gases
+
+	return 1
+
+/datum/gas_mixture/copy_from_turf(turf/model)
+	parse_gas_string(model.initial_gas_mix)
+
+	//acounts for changes in temperature
+	var/turf/model_parent = model.parent_type
+	if(model.temperature != initial(model.temperature) || model.temperature != initial(model_parent.temperature))
+		temperature = model.temperature
+
+	return 1
+
+/datum/gas_mixture/share(datum/gas_mixture/sharer, atmos_adjacent_turfs = 4)
+
+	var/list/cached_gases = gases
+	var/list/sharer_gases = sharer.gases
+
+	var/temperature_delta = temperature_archived - sharer.temperature_archived
+	var/abs_temperature_delta = abs(temperature_delta)
+
+	var/old_self_heat_capacity = 0
+	var/old_sharer_heat_capacity = 0
+	if(abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
+		old_self_heat_capacity = heat_capacity()
+		old_sharer_heat_capacity = sharer.heat_capacity()
+
+	var/heat_capacity_self_to_sharer = 0 //heat capacity of the moles transferred from us to the sharer
+	var/heat_capacity_sharer_to_self = 0 //heat capacity of the moles transferred from the sharer to us
+
+	var/moved_moles = 0
+	var/abs_moved_moles = 0
+
+	//we're gonna define these vars outside of this for loop because as it turns out, var declaration is pricy
+	var/delta
+	var/gas_heat_capacity
+	//and also cache this shit rq because that results in sanic speed for reasons byond explanation
+	var/list/cached_gasheats = GLOB.meta_gas_specific_heats
+	//GAS TRANSFER
+	for(var/id in cached_gases | sharer_gases) // transfer gases
+
+		delta = QUANTIZE(gas_archive[id] - sharer.gas_archive[id])/(atmos_adjacent_turfs+1) //the amount of gas that gets moved between the mixtures
+
+		if(delta && abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
+			gas_heat_capacity = delta * cached_gasheats[id]
+			if(delta > 0)
+				heat_capacity_self_to_sharer += gas_heat_capacity
+			else
+				heat_capacity_sharer_to_self -= gas_heat_capacity //subtract here instead of adding the absolute value because we know that delta is negative.
+
+		cached_gases[id]					-= delta
+		sharer_gases[id]			+= delta
+		moved_moles			+= delta
+		abs_moved_moles		+= abs(delta)
+
+	last_share = abs_moved_moles
+
+	//THERMAL ENERGY TRANSFER
+	if(abs_temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
+		var/new_self_heat_capacity = old_self_heat_capacity + heat_capacity_sharer_to_self - heat_capacity_self_to_sharer
+		var/new_sharer_heat_capacity = old_sharer_heat_capacity + heat_capacity_self_to_sharer - heat_capacity_sharer_to_self
+
+		//transfer of thermal energy (via changed heat capacity) between self and sharer
+		if(new_self_heat_capacity > MINIMUM_HEAT_CAPACITY)
+			temperature = (old_self_heat_capacity*temperature - heat_capacity_self_to_sharer*temperature_archived + heat_capacity_sharer_to_self*sharer.temperature_archived)/new_self_heat_capacity
+
+		if(new_sharer_heat_capacity > MINIMUM_HEAT_CAPACITY)
+			sharer.temperature = (old_sharer_heat_capacity*sharer.temperature-heat_capacity_sharer_to_self*sharer.temperature_archived + heat_capacity_self_to_sharer*temperature_archived)/new_sharer_heat_capacity
+		//thermal energy of the system (self and sharer) is unchanged
+
+			if(abs(old_sharer_heat_capacity) > MINIMUM_HEAT_CAPACITY)
+				if(abs(new_sharer_heat_capacity/old_sharer_heat_capacity - 1) < 0.1) // <10% change in sharer heat capacity
+					temperature_share(sharer, OPEN_HEAT_TRANSFER_COEFFICIENT)
+
+	if (initial(sharer.gc_share))
+		GAS_GARBAGE_COLLECT(sharer.gases)
+	if(temperature_delta > MINIMUM_TEMPERATURE_TO_MOVE || abs(moved_moles) > MINIMUM_MOLES_DELTA_TO_MOVE)
+		var/our_moles
+		TOTAL_MOLES(cached_gases,our_moles)
+		var/their_moles
+		TOTAL_MOLES(sharer_gases,their_moles)
+		return (temperature_archived*(our_moles + moved_moles) - sharer.temperature_archived*(their_moles - moved_moles)) * R_IDEAL_GAS_EQUATION / volume
+
+/datum/gas_mixture/temperature_share(datum/gas_mixture/sharer, conduction_coefficient, sharer_temperature, sharer_heat_capacity)
+	//transfer of thermal energy (via conduction) between self and sharer
+	if(sharer)
+		sharer_temperature = sharer.temperature_archived
+	var/temperature_delta = temperature_archived - sharer_temperature
+	if(abs(temperature_delta) > MINIMUM_TEMPERATURE_DELTA_TO_CONSIDER)
+		var/self_heat_capacity = archived_heat_capacity()
+		sharer_heat_capacity = sharer_heat_capacity || sharer.archived_heat_capacity()
+
+		if((sharer_heat_capacity > MINIMUM_HEAT_CAPACITY) && (self_heat_capacity > MINIMUM_HEAT_CAPACITY))
+			var/heat = conduction_coefficient*temperature_delta* \
+				(self_heat_capacity*sharer_heat_capacity/(self_heat_capacity+sharer_heat_capacity))
+
+			temperature = max(temperature - heat/self_heat_capacity, TCMB)
+			sharer_temperature = max(sharer_temperature + heat/sharer_heat_capacity, TCMB)
+			if(sharer)
+				sharer.temperature = sharer_temperature
+	return sharer_temperature
+	//thermal energy of the system (self and sharer) is unchanged
+
+/datum/gas_mixture/compare(datum/gas_mixture/sample)
+	var/list/sample_gases = sample.gases //accessing datum vars is slower than proc vars
+	var/list/cached_gases = gases
+
+	for(var/id in cached_gases | sample_gases) // compare gases from either mixture
+		var/gas_moles = cached_gases[id]
+		var/sample_moles = sample_gases[id]
+		var/delta = abs(gas_moles - sample_moles)
+		if(delta > MINIMUM_MOLES_DELTA_TO_MOVE && \
+			delta > gas_moles * MINIMUM_AIR_RATIO_TO_MOVE)
+			return id
+
+	var/our_moles
+	TOTAL_MOLES(cached_gases, our_moles)
+	if(our_moles > MINIMUM_MOLES_DELTA_TO_MOVE)
+		var/temp = temperature
+		var/sample_temp = sample.temperature
+
+		var/temperature_delta = abs(temp - sample_temp)
+		if(temperature_delta > MINIMUM_TEMPERATURE_DELTA_TO_SUSPEND)
+			return "temp"
+
+	return ""
+
+/datum/gas_mixture/transfer_to(datum/gas_mixture/target, amount)
+	return merge(target.remove(amount))
+
+#endif

code/modules/atmospherics/machinery/airalarm.dm

@@ -269,7 +269,7 @@
 							"unit" = "kPa",
 							"danger_level" = cur_tlv.get_danger_level(pressure)
 	))
-	var/temperature = environment.temperature
+	var/temperature = environment.return_temperature()
 	cur_tlv = TLV["temperature"]
 	data["environment_data"] += list(list(
 							"name" = "Temperature",
@@ -278,16 +278,16 @@
 							"danger_level" = cur_tlv.get_danger_level(temperature)
 	))
 	var/total_moles = environment.total_moles()
-	var/partial_pressure = R_IDEAL_GAS_EQUATION * environment.temperature / environment.volume
+	var/partial_pressure = R_IDEAL_GAS_EQUATION * environment.return_temperature() / environment.return_volume()
-	for(var/gas_id in environment.gases)
+	for(var/gas_id in environment.get_gases())
 		if(!(gas_id in TLV)) // We're not interested in this gas, it seems.
 			continue
 		cur_tlv = TLV[gas_id]
 		data["environment_data"] += list(list(
 								"name" = GLOB.meta_gas_names[gas_id],
-								"value" = environment.gases[gas_id] / total_moles * 100,
+								"value" = environment.get_moles(gas_id) / total_moles * 100,
 								"unit" = "%",
-								"danger_level" = cur_tlv.get_danger_level(environment.gases[gas_id] * partial_pressure)
+								"danger_level" = cur_tlv.get_danger_level(environment.get_moles(gas_id) * partial_pressure)
 		))
 
 	if(!locked || hasSiliconAccessInArea(user, PRIVILEDGES_SILICON|PRIVILEDGES_DRONE))
@@ -684,24 +684,21 @@
 	var/datum/tlv/cur_tlv
 
 	var/datum/gas_mixture/environment = location.return_air()
-	var/list/env_gases = environment.gases
+	var/partial_pressure = R_IDEAL_GAS_EQUATION * environment.return_temperature() / environment.return_volume()
-	var/partial_pressure = R_IDEAL_GAS_EQUATION * environment.temperature / environment.volume
 
 	cur_tlv = TLV["pressure"]
 	var/environment_pressure = environment.return_pressure()
 	var/pressure_dangerlevel = cur_tlv.get_danger_level(environment_pressure)
 
 	cur_tlv = TLV["temperature"]
-	var/temperature_dangerlevel = cur_tlv.get_danger_level(environment.temperature)
+	var/temperature_dangerlevel = cur_tlv.get_danger_level(environment.return_temperature())
 
 	var/gas_dangerlevel = 0
-	for(var/gas_id in env_gases)
+	for(var/gas_id in environment.get_gases())
 		if(!(gas_id in TLV)) // We're not interested in this gas, it seems.
 			continue
 		cur_tlv = TLV[gas_id]
-		gas_dangerlevel = max(gas_dangerlevel, cur_tlv.get_danger_level(env_gases[gas_id] * partial_pressure))
+		gas_dangerlevel = max(gas_dangerlevel, cur_tlv.get_danger_level(environment.get_moles(gas_id) * partial_pressure))
-
-	GAS_GARBAGE_COLLECT(environment.gases)
 
 	var/old_danger_level = danger_level
 	danger_level = max(pressure_dangerlevel, temperature_dangerlevel, gas_dangerlevel)

code/modules/atmospherics/machinery/components/binary_devices/circulator.dm

@@ -52,10 +52,10 @@
 		return null
 
 	//Calculate necessary moles to transfer using PV = nRT
-	if(air2.temperature>0)
+	if(air2.return_temperature()>0)
 		var/pressure_delta = (input_starting_pressure - output_starting_pressure)/2
 
-		var/transfer_moles = pressure_delta*air1.volume/(air2.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = pressure_delta*air1.return_volume()/(air2.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 		last_pressure_delta = pressure_delta
 

code/modules/atmospherics/machinery/components/binary_devices/dp_vent_pump.dm

@@ -66,8 +66,8 @@
 			pressure_delta = min(pressure_delta, (air1.return_pressure() - input_pressure_min))
 
 		if(pressure_delta > 0)
-			if(air1.temperature > 0)
+			if(air1.return_temperature() > 0)
-				var/transfer_moles = pressure_delta*environment.volume/(air1.temperature * R_IDEAL_GAS_EQUATION)
+				var/transfer_moles = pressure_delta*environment.return_volume()/(air1.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 				var/datum/gas_mixture/removed = air1.remove(transfer_moles)
 				//Removed can be null if there is no atmosphere in air1
@@ -81,20 +81,17 @@
 				parent1.update = 1
 
 	else //external -> output
-		var/pressure_delta = 10000
+		if(environment.return_pressure() > 0)
+			var/our_multiplier = air2.return_volume() / (environment.return_temperature() * R_IDEAL_GAS_EQUATION)
+			var/moles_delta = 10000 * our_multiplier
+			if(pressure_checks&EXT_BOUND)
+				moles_delta = min(moles_delta, (environment_pressure - output_pressure_max) * environment.return_volume() / (environment.return_temperature() * R_IDEAL_GAS_EQUATION))
+			if(pressure_checks&INPUT_MIN)
+				moles_delta = min(moles_delta, (input_pressure_min - air2.return_pressure()) * our_multiplier)
 
-		if(pressure_checks&EXT_BOUND)
+			if(moles_delta > 0)
-			pressure_delta = min(pressure_delta, (environment_pressure - external_pressure_bound))
+				var/datum/gas_mixture/removed = loc.remove_air(moles_delta)
-		if(pressure_checks&INPUT_MIN)
+				if (isnull(removed)) // in space
-			pressure_delta = min(pressure_delta, (output_pressure_max - air2.return_pressure()))
-
-		if(pressure_delta > 0)
-			if(environment.temperature > 0)
-				var/transfer_moles = pressure_delta*air2.volume/(environment.temperature * R_IDEAL_GAS_EQUATION)
-
-				var/datum/gas_mixture/removed = loc.remove_air(transfer_moles)
-				//removed can be null if there is no air in the location
-				if(!removed)
 					return
 
 				air2.merge(removed)
@@ -182,8 +179,8 @@
 	..()
 	var/datum/gas_mixture/air1 = airs[1]
 	var/datum/gas_mixture/air2 = airs[2]
-	air1.volume = 1000
+	air1.set_volume(1000)
-	air2.volume = 1000
+	air2.set_volume(1000)
 
 // Mapping
 

code/modules/atmospherics/machinery/components/binary_devices/passive_gate.dm

@@ -53,11 +53,11 @@ Passive gate is similar to the regular pump except:
 		return
 
 	//Calculate necessary moles to transfer using PV = nRT
-	if((air1.total_moles() > 0) && (air1.temperature>0))
+	if((air1.total_moles() > 0) && (air1.return_temperature()>0))
 		var/pressure_delta = min(target_pressure - output_starting_pressure, (input_starting_pressure - output_starting_pressure)/2)
 		//Can not have a pressure delta that would cause output_pressure > input_pressure
 
-		var/transfer_moles = pressure_delta*air2.volume/(air1.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = pressure_delta*air2.return_volume()/(air1.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 		//Actually transfer the gas
 		var/datum/gas_mixture/removed = air1.remove(transfer_moles)

code/modules/atmospherics/machinery/components/binary_devices/pump.dm

@@ -77,9 +77,9 @@
 		return
 
 	//Calculate necessary moles to transfer using PV=nRT
-	if((air1.total_moles() > 0) && (air1.temperature>0))
+	if((air1.total_moles() > 0) && (air1.return_temperature()>0))
 		var/pressure_delta = target_pressure - output_starting_pressure
-		var/transfer_moles = pressure_delta*air2.volume/(air1.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = pressure_delta*air2.return_volume()/(air1.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 		//Actually transfer the gas
 		var/datum/gas_mixture/removed = air1.remove(transfer_moles)

code/modules/atmospherics/machinery/components/binary_devices/volume_pump.dm

@@ -65,7 +65,7 @@
 	if((input_starting_pressure < 0.01) || (output_starting_pressure > 9000))
 		return
 
-	var/transfer_ratio = transfer_rate/air1.volume
+	var/transfer_ratio = transfer_rate/air1.return_volume()
 
 	var/datum/gas_mixture/removed = air1.remove_ratio(transfer_ratio)
 
@@ -153,7 +153,7 @@
 
 	if("set_transfer_rate" in signal.data)
 		var/datum/gas_mixture/air1 = airs[1]
-		transfer_rate = clamp(text2num(signal.data["set_transfer_rate"]),0,air1.volume)
+		transfer_rate = clamp(text2num(signal.data["set_transfer_rate"]),0,air1.return_volume())
 
 	if(on != old_on)
 		investigate_log("was turned [on ? "on" : "off"] by a remote signal", INVESTIGATE_ATMOS)

code/modules/atmospherics/machinery/components/components_base.dm

@@ -15,8 +15,7 @@
 	..()
 
 	for(var/i in 1 to device_type)
-		var/datum/gas_mixture/A = new
+		var/datum/gas_mixture/A = new(200)
-		A.volume = 200
 		airs[i] = A
 
 // Iconnery
@@ -117,7 +116,7 @@
 		var/times_lost = 0
 		for(var/i in 1 to device_type)
 			var/datum/gas_mixture/air = airs[i]
-			lost += pressures*environment.volume/(air.temperature * R_IDEAL_GAS_EQUATION)
+			lost += pressures*environment.return_volume()/(air.return_temperature() * R_IDEAL_GAS_EQUATION)
 			times_lost++
 		var/shared_loss = lost/times_lost
 

code/modules/atmospherics/machinery/components/trinary_devices/filter.dm

@@ -94,7 +94,7 @@
 
 	//Calculate necessary moles to transfer using PV=nRT
 
-	var/transfer_ratio = transfer_rate/air1.volume
+	var/transfer_ratio = transfer_rate/air1.return_volume()
 
 	//Actually transfer the gas
 
@@ -111,14 +111,13 @@
 			else
 				filtering = FALSE
 
-		if(filtering && removed.gases[filter_type])
+		if(filtering && removed.get_moles(filter_type))
 			var/datum/gas_mixture/filtered_out = new
 
-			filtered_out.temperature = removed.temperature
+			filtered_out.set_temperature(removed.return_temperature())
-			filtered_out.gases[filter_type] = removed.gases[filter_type]
+			filtered_out.set_moles(filter_type, removed.get_moles(filter_type))
 
-			removed.gases[filter_type] = 0
+			removed.set_moles(filter_type, 0)
-			GAS_GARBAGE_COLLECT(removed.gases)
 
 			var/datum/gas_mixture/target = (air2.return_pressure() < 9000 ? air2 : air1)
 			target.merge(filtered_out)

code/modules/atmospherics/machinery/components/trinary_devices/mixer.dm

@@ -57,7 +57,7 @@
 /obj/machinery/atmospherics/components/trinary/mixer/New()
 	..()
 	var/datum/gas_mixture/air3 = airs[3]
-	air3.volume = 300
+	air3.set_volume(300)
 	airs[3] = air3
 
 /obj/machinery/atmospherics/components/trinary/mixer/process_atmos()
@@ -81,26 +81,26 @@
 		return
 
 	//Calculate necessary moles to transfer using PV=nRT
-	var/general_transfer = (target_pressure - output_starting_pressure) * air3.volume / R_IDEAL_GAS_EQUATION
+	var/general_transfer = (target_pressure - output_starting_pressure) * air3.return_volume() / R_IDEAL_GAS_EQUATION
 
-	var/transfer_moles1 = air1.temperature ? node1_concentration * general_transfer / air1.temperature : 0
+	var/transfer_moles1 = air1.return_temperature() ? node1_concentration * general_transfer / air1.return_temperature() : 0
-	var/transfer_moles2 = air2.temperature ? node2_concentration * general_transfer / air2.temperature : 0
+	var/transfer_moles2 = air2.return_temperature() ? node2_concentration * general_transfer / air2.return_temperature() : 0
 
 	var/air1_moles = air1.total_moles()
 	var/air2_moles = air2.total_moles()
 
 	if(!node2_concentration)
-		if(air1.temperature <= 0)
+		if(air1.return_temperature() <= 0)
 			return
 		transfer_moles1 = min(transfer_moles1, air1_moles)
 		transfer_moles2 = 0
 	else if(!node1_concentration)
-		if(air2.temperature <= 0)
+		if(air2.return_temperature() <= 0)
 			return
 		transfer_moles2 = min(transfer_moles2, air2_moles)
 		transfer_moles1 = 0
 	else
-		if(air1.temperature <= 0 || air2.temperature <= 0)
+		if(air1.return_temperature() <= 0 || air2.return_temperature() <= 0)
 			return
 		if((transfer_moles2 <= 0) || (transfer_moles1 <= 0))
 			return

code/modules/atmospherics/machinery/components/unary_devices/cryo.dm

@@ -186,7 +186,7 @@
 
 	var/datum/gas_mixture/air1 = airs[1]
 
-	if(air1.gases.len)
+	if(air1.total_moles())
 		if(mob_occupant.bodytemperature < T0C) // Sleepytime. Why? More cryo magic.
 			// temperature factor goes from 1 to about 2.5
 			var/amount = max(1, (4 * log(T0C - mob_occupant.bodytemperature)) - 20) * knockout_factor * base_knockout
@@ -196,8 +196,7 @@
 			if(reagent_transfer == 0) // Magically transfer reagents. Because cryo magic.
 				beaker.reagents.trans_to(occupant, 1, efficiency * 0.25) // Transfer reagents.
 				beaker.reagents.reaction(occupant, VAPOR)
-				air1.gases[/datum/gas/oxygen] -= max(0,air1.gases[/datum/gas/oxygen] - 2 / efficiency) //Let's use gas for this
+				air1.adjust_moles(/datum/gas/oxygen, -max(0,air1.get_moles(/datum/gas/oxygen) - 2 / efficiency)) //Let's use gas for this
-				GAS_GARBAGE_COLLECT(air1.gases)
 			if(++reagent_transfer >= 10 * efficiency) // Throttle reagent transfer (higher efficiency will transfer the same amount but consume less from the beaker).
 				reagent_transfer = 0
 
@@ -211,7 +210,7 @@
 
 	var/datum/gas_mixture/air1 = airs[1]
 
-	if(!nodes[1] || !airs[1] || !air1.gases.len || air1.gases[/datum/gas/oxygen] < 5) // Turn off if the machine won't work.
+	if(!nodes[1] || !airs[1] || air1.get_moles(/datum/gas/oxygen) < 5) // Turn off if the machine won't work.
 		on = FALSE
 		update_icon()
 		return
@@ -219,22 +218,21 @@
 	if(occupant)
 		var/mob/living/mob_occupant = occupant
 		var/cold_protection = 0
-		var/temperature_delta = air1.temperature - mob_occupant.bodytemperature // The only semi-realistic thing here: share temperature between the cell and the occupant.
+		var/temperature_delta = air1.return_temperature() - mob_occupant.bodytemperature // The only semi-realistic thing here: share temperature between the cell and the occupant.
 
 		if(ishuman(occupant))
 			var/mob/living/carbon/human/H = occupant
-			cold_protection = H.get_thermal_protection(air1.temperature, TRUE)
+			cold_protection = H.get_thermal_protection(air1.return_temperature(), TRUE)
 
 		if(abs(temperature_delta) > 1)
 			var/air_heat_capacity = air1.heat_capacity()
 
 			var/heat = ((1 - cold_protection) * 0.1 + conduction_coefficient) * temperature_delta * (air_heat_capacity * heat_capacity / (air_heat_capacity + heat_capacity))
 
-			air1.temperature = max(air1.temperature - heat / air_heat_capacity, TCMB)
+			air1.set_temperature(max(air1.return_temperature() - heat / air_heat_capacity, TCMB))
 			mob_occupant.adjust_bodytemperature(heat / heat_capacity, TCMB)
 
-		air1.gases[/datum/gas/oxygen] = max(0,air1.gases[/datum/gas/oxygen] - 0.5 / efficiency) // Magically consume gas? Why not, we run on cryo magic.
+		air1.set_temperature(max(air1.return_temperature() - 0.5 / efficiency)) // Magically consume gas? Why not, we run on cryo magic.
-		GAS_GARBAGE_COLLECT(air1.gases)
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/power_change()
 	..()
@@ -369,7 +367,7 @@
 			data["occupant"]["temperaturestatus"] = "bad"
 
 	var/datum/gas_mixture/air1 = airs[1]
-	data["cellTemperature"] = round(air1.temperature, 1)
+	data["cellTemperature"] = round(air1.return_temperature(), 1)
 
 	data["isBeakerLoaded"] = beaker ? TRUE : FALSE
 	var/beakerContents = list()
@@ -439,7 +437,7 @@
 	var/datum/gas_mixture/G = airs[1]
 
 	if(G.total_moles() > 10)
-		return G.temperature
+		return G.return_temperature()
 	return ..()
 
 /obj/machinery/atmospherics/components/unary/cryo_cell/default_change_direction_wrench(mob/user, obj/item/wrench/W)

code/modules/atmospherics/machinery/components/unary_devices/heat_exchanger.dm

@@ -59,18 +59,18 @@
 	var/other_air_heat_capacity = partner_air_contents.heat_capacity()
 	var/combined_heat_capacity = other_air_heat_capacity + air_heat_capacity
 
-	var/old_temperature = air_contents.temperature
+	var/old_temperature = air_contents.return_temperature()
-	var/other_old_temperature = partner_air_contents.temperature
+	var/other_old_temperature = partner_air_contents.return_temperature()
 
 	if(combined_heat_capacity > 0)
-		var/combined_energy = partner_air_contents.temperature*other_air_heat_capacity + air_heat_capacity*air_contents.temperature
+		var/combined_energy = partner_air_contents.return_temperature()*other_air_heat_capacity + air_heat_capacity*air_contents.return_temperature()
 
 		var/new_temperature = combined_energy/combined_heat_capacity
-		air_contents.temperature = new_temperature
+		air_contents.set_temperature(new_temperature)
-		partner_air_contents.temperature = new_temperature
+		partner_air_contents.set_temperature(new_temperature)
 
-	if(abs(old_temperature-air_contents.temperature) > 1)
+	if(abs(old_temperature-air_contents.return_temperature()) > 1)
 		update_parents()
 
-	if(abs(other_old_temperature-partner_air_contents.temperature) > 1)
+	if(abs(other_old_temperature-partner_air_contents.return_temperature()) > 1)
 		partner.update_parents()

code/modules/atmospherics/machinery/components/unary_devices/outlet_injector.dm

@@ -52,8 +52,8 @@
 
 	var/datum/gas_mixture/air_contents = airs[1]
 
-	if(air_contents.temperature > 0)
+	if(air_contents.return_temperature() > 0)
-		var/transfer_moles = (air_contents.return_pressure())*volume_rate/(air_contents.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = (air_contents.return_pressure())*volume_rate/(air_contents.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 		var/datum/gas_mixture/removed = air_contents.remove(transfer_moles)
 
@@ -71,8 +71,8 @@
 
 	injecting = 1
 
-	if(air_contents.temperature > 0)
+	if(air_contents.return_temperature() > 0)
-		var/transfer_moles = (air_contents.return_pressure())*volume_rate/(air_contents.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = (air_contents.return_pressure())*volume_rate/(air_contents.return_temperature() * R_IDEAL_GAS_EQUATION)
 		var/datum/gas_mixture/removed = air_contents.remove(transfer_moles)
 		loc.assume_air(removed)
 		update_parents()
@@ -123,7 +123,7 @@
 	if("set_volume_rate" in signal.data)
 		var/number = text2num(signal.data["set_volume_rate"])
 		var/datum/gas_mixture/air_contents = airs[1]
-		volume_rate = clamp(number, 0, air_contents.volume)
+		volume_rate = clamp(number, 0, air_contents.return_volume())
 
 	if("status" in signal.data)
 		spawn(2)

code/modules/atmospherics/machinery/components/unary_devices/passive_vent.dm

@@ -30,14 +30,14 @@
 
 	if(pressure_delta > 0.5)
 		if(external_pressure < internal_pressure)
-			var/air_temperature = (external.temperature > 0) ? external.temperature : internal.temperature
+			var/air_temperature = (external.return_temperature() > 0) ? external.return_temperature() : internal.return_temperature()
-			var/transfer_moles = (pressure_delta * external.volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
+			var/transfer_moles = (pressure_delta * external.return_volume()) / (air_temperature * R_IDEAL_GAS_EQUATION)
 			var/datum/gas_mixture/removed = internal.remove(transfer_moles)
 			external.merge(removed)
 		else
-			var/air_temperature = (internal.temperature > 0) ? internal.temperature : external.temperature
+			var/air_temperature = (internal.return_temperature() > 0) ? internal.return_temperature() : external.return_temperature()
-			var/transfer_moles = (pressure_delta * internal.volume) / (air_temperature * R_IDEAL_GAS_EQUATION)
+			var/transfer_moles = (pressure_delta * internal.return_volume()) / (air_temperature * R_IDEAL_GAS_EQUATION)
-			transfer_moles = min(transfer_moles, external.total_moles() * internal.volume / external.volume)
+			transfer_moles = min(transfer_moles, external.total_moles() * internal.return_volume() / external.return_volume())
 			var/datum/gas_mixture/removed = external.remove(transfer_moles)
 			if(isnull(removed))
 				return

code/modules/atmospherics/machinery/components/unary_devices/portables_connector.dm

@@ -16,7 +16,7 @@
 	..()
 	var/datum/gas_mixture/air_contents = airs[1]
 
-	air_contents.volume = 0
+	air_contents.set_volume(0)
 
 /obj/machinery/atmospherics/components/unary/portables_connector/Destroy()
 	if(connected_device)

code/modules/atmospherics/machinery/components/unary_devices/relief_valve.dm

@@ -49,10 +49,10 @@
 	else if(!opened && our_pressure >= open_pressure)
 		opened = TRUE
 		update_icon_nopipes()
-	if(opened && air_contents.temperature > 0)
+	if(opened && air_contents.return_temperature() > 0)
 		var/datum/gas_mixture/environment = loc.return_air()
 		var/pressure_delta = our_pressure - environment.return_pressure()
-		var/transfer_moles = pressure_delta*200/(air_contents.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = pressure_delta*200/(air_contents.return_temperature() * R_IDEAL_GAS_EQUATION)
 		if(transfer_moles > 0)
 			var/datum/gas_mixture/removed = air_contents.remove(transfer_moles)
 

code/modules/atmospherics/machinery/components/unary_devices/tank.dm

@@ -1,4 +1,4 @@
-#define AIR_CONTENTS	((25*ONE_ATMOSPHERE)*(air_contents.volume)/(R_IDEAL_GAS_EQUATION*air_contents.temperature))
+#define AIR_CONTENTS	((25*ONE_ATMOSPHERE)*(air_contents.return_volume())/(R_IDEAL_GAS_EQUATION*air_contents.return_temperature()))
 /obj/machinery/atmospherics/components/unary/tank
 	icon = 'icons/obj/atmospherics/pipes/pressure_tank.dmi'
 	icon_state = "generic"
@@ -15,10 +15,10 @@
 /obj/machinery/atmospherics/components/unary/tank/New()
 	..()
 	var/datum/gas_mixture/air_contents = airs[1]
-	air_contents.volume = volume
+	air_contents.set_volume(volume)
-	air_contents.temperature = T20C
+	air_contents.set_temperature(T20C)
 	if(gas_type)
-		air_contents.gases[gas_type] = AIR_CONTENTS
+		air_contents.set_moles(AIR_CONTENTS)
 		name = "[name] ([GLOB.meta_gas_names[gas_type]])"
 
 /obj/machinery/atmospherics/components/unary/tank/air
@@ -28,8 +28,8 @@
 /obj/machinery/atmospherics/components/unary/tank/air/New()
 	..()
 	var/datum/gas_mixture/air_contents = airs[1]
-	air_contents.gases[/datum/gas/oxygen] = AIR_CONTENTS * 0.2
+	air_contents.set_moles(/datum/gas/oxygen, AIR_CONTENTS * 0.2)
-	air_contents.gases[/datum/gas/nitrogen] = AIR_CONTENTS * 0.8
+	air_contents.set_moles(/datum/gas/nitrogen, AIR_CONTENTS * 0.8)
 
 /obj/machinery/atmospherics/components/unary/tank/carbon_dioxide
 	gas_type = /datum/gas/carbon_dioxide

code/modules/atmospherics/machinery/components/unary_devices/thermomachine.dm

@@ -74,13 +74,13 @@
 
 	var/air_heat_capacity = air_contents.heat_capacity()
 	var/combined_heat_capacity = heat_capacity + air_heat_capacity
-	var/old_temperature = air_contents.temperature
+	var/old_temperature = air_contents.return_temperature()
 
 	if(combined_heat_capacity > 0)
-		var/combined_energy = heat_capacity * target_temperature + air_heat_capacity * air_contents.temperature
+		var/combined_energy = heat_capacity * target_temperature + air_heat_capacity * air_contents.return_temperature()
-		air_contents.temperature = combined_energy/combined_heat_capacity
+		air_contents.set_temperature(combined_energy/combined_heat_capacity)
 
-	var/temperature_delta= abs(old_temperature - air_contents.temperature)
+	var/temperature_delta= abs(old_temperature - air_contents.return_temperature())
 	if(temperature_delta > 1)
 		active_power_usage = (heat_capacity * temperature_delta) / 10 + idle_power_usage
 		update_parents()
@@ -142,7 +142,7 @@
 	data["initial"] = initial(target_temperature)
 
 	var/datum/gas_mixture/air1 = airs[1]
-	data["temperature"] = air1.temperature
+	data["temperature"] = air1.return_temperature()
 	data["pressure"] = air1.return_pressure()
 	return data
 

code/modules/atmospherics/machinery/components/unary_devices/vent_pump.dm

@@ -104,8 +104,8 @@
 			pressure_delta = min(pressure_delta, (air_contents.return_pressure() - internal_pressure_bound))
 
 		if(pressure_delta > 0)
-			if(air_contents.temperature > 0)
+			if(air_contents.return_temperature() > 0)
-				var/transfer_moles = pressure_delta*environment.volume/(air_contents.temperature * R_IDEAL_GAS_EQUATION)
+				var/transfer_moles = pressure_delta*environment.return_volume()/(air_contents.return_temperature() * R_IDEAL_GAS_EQUATION)
 
 				var/datum/gas_mixture/removed = air_contents.remove(transfer_moles)
 
@@ -113,21 +113,21 @@
 				air_update_turf()
 
 	else // external -> internal
-		var/pressure_delta = 10000
+		if(environment.return_pressure() > 0)
-		if(pressure_checks&EXT_BOUND)
+			var/our_multiplier = air_contents.return_volume() / (environment.return_temperature() * R_IDEAL_GAS_EQUATION)
-			pressure_delta = min(pressure_delta, (environment_pressure - external_pressure_bound))
+			var/moles_delta = 10000 * our_multiplier
-		if(pressure_checks&INT_BOUND)
+			if(pressure_checks&EXT_BOUND)
-			pressure_delta = min(pressure_delta, (internal_pressure_bound - air_contents.return_pressure()))
+				moles_delta = min(moles_delta, (environment_pressure - external_pressure_bound) * environment.return_volume() / (environment.return_temperature() * R_IDEAL_GAS_EQUATION))
+			if(pressure_checks&INT_BOUND)
+				moles_delta = min(moles_delta, (internal_pressure_bound - air_contents.return_pressure()) * our_multiplier)
 
-		if(pressure_delta > 0 && environment.temperature > 0)
+			if(moles_delta > 0)
-			var/transfer_moles = pressure_delta * air_contents.volume / (environment.temperature * R_IDEAL_GAS_EQUATION)
+				var/datum/gas_mixture/removed = loc.remove_air(moles_delta)
+				if (isnull(removed)) // in space
+					return
 
-			var/datum/gas_mixture/removed = loc.remove_air(transfer_moles)
+				air_contents.merge(removed)
-			if (isnull(removed)) // in space
+				air_update_turf()
-				return
-
-			air_contents.merge(removed)
-			air_update_turf()
 	update_parents()
 
 //Radio remote control
@@ -295,7 +295,7 @@
 /obj/machinery/atmospherics/components/unary/vent_pump/high_volume/New()
 	..()
 	var/datum/gas_mixture/air_contents = airs[1]
-	air_contents.volume = 1000
+	air_contents.set_volume(1000)
 
 // mapping
 

code/modules/atmospherics/machinery/components/unary_devices/vent_scrubber.dm

@@ -149,43 +149,29 @@
 		return FALSE
 	var/datum/gas_mixture/environment = tile.return_air()
 	var/datum/gas_mixture/air_contents = airs[1]
-	var/list/env_gases = environment.gases
 
 	if(air_contents.return_pressure() >= 50*ONE_ATMOSPHERE)
 		return FALSE
 
 	if(scrubbing & SCRUBBING)
-		if(length(env_gases & filter_types))
+		var/transfer_moles = min(1, volume_rate/environment.return_volume())*environment.total_moles()
-			var/transfer_moles = min(1, volume_rate/environment.volume)*environment.total_moles()
 
-			//Take a gas sample
+		//Take a gas sample
-			var/datum/gas_mixture/removed = tile.remove_air(transfer_moles)
+		var/datum/gas_mixture/removed = tile.remove_air(transfer_moles)
 
-			//Nothing left to remove from the tile
+		//Nothing left to remove from the tile
-			if(isnull(removed))
+		if(isnull(removed))
-				return FALSE
+			return FALSE
 
-			var/list/removed_gases = removed.gases
+		removed.scrub_into(air_contents, filter_types)
 
-			//Filter it
+		//Remix the resulting gases
-			var/datum/gas_mixture/filtered_out = new
+		tile.assume_air(removed)
-			var/list/filtered_gases = filtered_out.gases
+		tile.air_update_turf()
-			filtered_out.temperature = removed.temperature
-
-			for(var/gas in filter_types & removed_gases)
-				filtered_gases[gas] = removed_gases[gas]
-				removed_gases[gas] = 0
-
-			GAS_GARBAGE_COLLECT(removed.gases)
-
-			//Remix the resulting gases
-			air_contents.merge(filtered_out)
-			tile.assume_air(removed)
-			tile.air_update_turf()
 
 	else //Just siphoning all air
 
-		var/transfer_moles = environment.total_moles()*(volume_rate/environment.volume)
+		var/transfer_moles = environment.total_moles()*(volume_rate/environment.return_volume())
 
 		var/datum/gas_mixture/removed = tile.remove_air(transfer_moles)
 

code/modules/atmospherics/machinery/datum_pipeline.dm

@@ -15,7 +15,7 @@
 
 /datum/pipeline/Destroy()
 	SSair.networks -= src
-	if(air && air.volume)
+	if(air && air.return_volume())
 		temporarily_store_air()
 	for(var/obj/machinery/atmospherics/pipe/P in members)
 		P.parent = null
@@ -76,7 +76,7 @@
 
 			possible_expansions -= borderline
 
-	air.volume = volume
+	air.set_volume(volume)
 
 /datum/pipeline/proc/addMachineryMember(obj/machinery/atmospherics/components/C)
 	other_atmosmch |= C
@@ -99,7 +99,7 @@
 			merge(E)
 		if(!members.Find(P))
 			members += P
-			air.volume += P.volume
+			air.set_volume(air.return_volume() + P.volume)
 	else
 		A.setPipenet(src, N)
 		addMachineryMember(A)
@@ -107,7 +107,7 @@
 /datum/pipeline/proc/merge(datum/pipeline/E)
 	if(E == src)
 		return
-	air.volume += E.air.volume
+	air.set_volume(air.return_volume() + E.air.return_volume())
 	members.Add(E.members)
 	for(var/obj/machinery/atmospherics/pipe/S in E.members)
 		S.parent = src
@@ -139,18 +139,16 @@
 
 	for(var/obj/machinery/atmospherics/pipe/member in members)
 		member.air_temporary = new
-		member.air_temporary.volume = member.volume
+		member.air_temporary.set_volume(member.volume)
 		member.air_temporary.copy_from(air)
-		var/member_gases = member.air_temporary.gases
 
-		for(var/id in member_gases)
+		member.air_temporary.multiply(member.volume/air.return_volume())
-			member_gases[id] *= member.volume/air.volume
 
-		member.air_temporary.temperature = air.temperature
+		member.air_temporary.set_temperature(air.return_temperature())
 
 /datum/pipeline/proc/temperature_interact(turf/target, share_volume, thermal_conductivity)
 	var/total_heat_capacity = air.heat_capacity()
-	var/partial_heat_capacity = total_heat_capacity*(share_volume/air.volume)
+	var/partial_heat_capacity = total_heat_capacity*(share_volume/air.return_volume())
 	var/target_temperature
 	var/target_heat_capacity
 
@@ -163,19 +161,19 @@
 		if(modeled_location.blocks_air)
 
 			if((modeled_location.heat_capacity>0) && (partial_heat_capacity>0))
-				var/delta_temperature = air.temperature - target_temperature
+				var/delta_temperature = air.return_temperature() - target_temperature
 
 				var/heat = thermal_conductivity*delta_temperature* \
 					(partial_heat_capacity*target_heat_capacity/(partial_heat_capacity+target_heat_capacity))
 
-				air.temperature -= heat/total_heat_capacity
+				air.set_temperature(air.return_temperature() - heat/total_heat_capacity)
 				modeled_location.TakeTemperature(heat/target_heat_capacity)
 
 		else
 			var/delta_temperature = 0
 			var/sharer_heat_capacity = 0
 
-			delta_temperature = (air.temperature - target_temperature)
+			delta_temperature = (air.return_temperature() - target_temperature)
 			sharer_heat_capacity = target_heat_capacity
 
 			var/self_temperature_delta = 0
@@ -190,18 +188,18 @@
 			else
 				return 1
 
-			air.temperature += self_temperature_delta
+			air.set_temperature(air.return_temperature() + self_temperature_delta)
 			modeled_location.TakeTemperature(sharer_temperature_delta)
 
 
 	else
 		if((target.heat_capacity>0) && (partial_heat_capacity>0))
-			var/delta_temperature = air.temperature - target.temperature
+			var/delta_temperature = air.return_temperature() - target.return_temperature()
 
 			var/heat = thermal_conductivity*delta_temperature* \
 				(partial_heat_capacity*target.heat_capacity/(partial_heat_capacity+target.heat_capacity))
 
-			air.temperature -= heat/total_heat_capacity
+			air.set_temperature(air.return_temperature() - heat/total_heat_capacity)
 	update = TRUE
 
 /datum/pipeline/proc/return_air()
@@ -242,20 +240,18 @@
 
 	for(var/i in GL)
 		var/datum/gas_mixture/G = i
-		total_gas_mixture.volume += G.volume
+		total_gas_mixture.set_volume(total_gas_mixture.return_volume() + G.return_volume())
 
 		total_gas_mixture.merge(G)
 
-		total_thermal_energy += THERMAL_ENERGY(G)
+		total_thermal_energy += G.thermal_energy()
 		total_heat_capacity += G.heat_capacity()
 
-	total_gas_mixture.temperature = total_heat_capacity ? total_thermal_energy/total_heat_capacity : 0
+	total_gas_mixture.set_temperature(total_heat_capacity ? total_thermal_energy/total_heat_capacity : 0)
 
-	if(total_gas_mixture.volume > 0)
+	if(total_gas_mixture.return_volume() > 0)
 		//Update individual gas_mixtures by volume ratio
 		for(var/i in GL)
 			var/datum/gas_mixture/G = i
 			G.copy_from(total_gas_mixture)
-			var/list/G_gases = G.gases
+			G.multiply(G.return_volume()/total_gas_mixture.return_volume())
-			for(var/id in G_gases)
-				G_gases[id] *= G.volume/total_gas_mixture.volume

code/modules/atmospherics/machinery/other/meter.dm

@@ -103,7 +103,7 @@
 	if (target)
 		var/datum/gas_mixture/environment = target.return_air()
 		if(environment)
-			. = "The pressure gauge reads [round(environment.return_pressure(), 0.01)] kPa; [round(environment.temperature,0.01)] K ([round(environment.temperature-T0C,0.01)]°C)."
+			. = "The pressure gauge reads [round(environment.return_pressure(), 0.01)] kPa; [round(environment.return_temperature(),0.01)] K ([round(environment.return_temperature()-T0C,0.01)]°C)."
 		else
 			. = "The sensor error light is blinking."
 	else

code/modules/atmospherics/machinery/other/miner.dm

@@ -131,8 +131,8 @@
 	if(!isopenturf(O))
 		return FALSE
 	var/datum/gas_mixture/merger = new
-	merger.gases[spawn_id] = (spawn_mol)
+	merger.set_moles(spawn_id, spawn_mol)
-	merger.temperature = spawn_temp
+	merger.set_temperature(spawn_temp)
 	O.assume_air(merger)
 	O.air_update_turf(TRUE)
 

code/modules/atmospherics/machinery/pipes/heat_exchange/he_pipes.dm

@@ -28,14 +28,14 @@
 		if(islava(T))
 			environment_temperature = 5000
 		else if(T.blocks_air)
-			environment_temperature = T.temperature
+			environment_temperature = T.return_temperature()
 		else
 			var/turf/open/OT = T
 			environment_temperature = OT.GetTemperature()
 	else
-		environment_temperature = T.temperature
+		environment_temperature = T.return_temperature()
 
-	if(abs(environment_temperature-pipe_air.temperature) > minimum_temperature_difference)
+	if(abs(environment_temperature-pipe_air.return_temperature()) > minimum_temperature_difference)
 		parent.temperature_interact(T, volume, thermal_conductivity)
 
 
@@ -44,11 +44,11 @@
 		var/hc = pipe_air.heat_capacity()
 		var/mob/living/heat_source = buckled_mobs[1]
 		//Best guess-estimate of the total bodytemperature of all the mobs, since they share the same environment it's ~ok~ to guess like this
-		var/avg_temp = (pipe_air.temperature * hc + (heat_source.bodytemperature * buckled_mobs.len) * 3500) / (hc + (buckled_mobs ? buckled_mobs.len * 3500 : 0))
+		var/avg_temp = (pipe_air.return_temperature() * hc + (heat_source.bodytemperature * buckled_mobs.len) * 3500) / (hc + (buckled_mobs ? buckled_mobs.len * 3500 : 0))
 		for(var/m in buckled_mobs)
 			var/mob/living/L = m
 			L.bodytemperature = avg_temp
-		pipe_air.temperature = avg_temp
+		pipe_air.set_temperature(avg_temp)
 
 /obj/machinery/atmospherics/pipe/heat_exchanging/process()
 	if(!parent)
@@ -57,9 +57,9 @@
 	var/datum/gas_mixture/pipe_air = return_air()
 
 	//Heat causes pipe to glow
-	if(pipe_air.temperature && (icon_temperature > 500 || pipe_air.temperature > 500)) //glow starts at 500K
+	if(pipe_air.return_temperature() && (icon_temperature > 500 || pipe_air.return_temperature() > 500)) //glow starts at 500K
-		if(abs(pipe_air.temperature - icon_temperature) > 10)
+		if(abs(pipe_air.return_temperature() - icon_temperature) > 10)
-			icon_temperature = pipe_air.temperature
+			icon_temperature = pipe_air.return_temperature()
 
 			var/h_r = heat2colour_r(icon_temperature)
 			var/h_g = heat2colour_g(icon_temperature)
@@ -76,7 +76,7 @@
 	//burn any mobs buckled based on temperature
 	if(has_buckled_mobs())
 		var/heat_limit = 1000
-		if(pipe_air.temperature > heat_limit + 1)
+		if(pipe_air.return_temperature() > heat_limit + 1)
 			for(var/m in buckled_mobs)
 				var/mob/living/buckled_mob = m
-				buckled_mob.apply_damage(4 * log(pipe_air.temperature - heat_limit), BURN, BODY_ZONE_CHEST)
+				buckled_mob.apply_damage(4 * log(pipe_air.return_temperature() - heat_limit), BURN, BODY_ZONE_CHEST)

code/modules/atmospherics/machinery/portable/canister.dm

@@ -200,14 +200,14 @@
 /obj/machinery/portable_atmospherics/canister/proc/create_gas()
 	if(gas_type)
 		if(starter_temp)
-			air_contents.temperature = starter_temp
+			air_contents.set_temperature(starter_temp)
-		air_contents.gases[gas_type] = (maximum_pressure * filled) * air_contents.volume / (R_IDEAL_GAS_EQUATION * air_contents.temperature)
+		air_contents.set_moles(gas_type,(maximum_pressure * filled) * air_contents.return_volume() / (R_IDEAL_GAS_EQUATION * air_contents.return_temperature()))
 		if(starter_temp)
-			air_contents.temperature = starter_temp
+			air_contents.set_temperature(starter_temp)
 
 /obj/machinery/portable_atmospherics/canister/air/create_gas()
-	air_contents.gases[/datum/gas/oxygen] = (O2STANDARD * maximum_pressure * filled) * air_contents.volume / (R_IDEAL_GAS_EQUATION * air_contents.temperature)
+	air_contents.set_moles(/datum/gas/oxygen, (O2STANDARD * maximum_pressure * filled) * air_contents.return_volume() / (R_IDEAL_GAS_EQUATION * air_contents.return_temperature()))
-	air_contents.gases[/datum/gas/nitrogen] = (N2STANDARD * maximum_pressure * filled) * air_contents.volume / (R_IDEAL_GAS_EQUATION * air_contents.temperature)
+	air_contents.set_moles(/datum/gas/nitrogen, (N2STANDARD * maximum_pressure * filled) * air_contents.return_volume() / (R_IDEAL_GAS_EQUATION * air_contents.return_temperature()))
 
 /obj/machinery/portable_atmospherics/canister/update_icon_state()
 	if(stat & BROKEN)
@@ -397,8 +397,8 @@
 				logmsg = "Valve was <b>opened</b> by [key_name(usr)], starting a transfer into \the [holding || "air"].<br>"
 				if(!holding)
 					var/list/danger = list()
-					for(var/id in air_contents.gases)
+					for(var/id in air_contents.get_gases())
-						var/gas = air_contents.gases[id]
+						var/gas = air_contents.get_moles(id)
 						if(!GLOB.meta_gas_dangers[id])
 							continue
 						if(gas > (GLOB.meta_gas_visibility[id] || MOLES_GAS_VISIBLE)) //if moles_visible is undefined, default to default visibility

code/modules/atmospherics/machinery/portable/portable_atmospherics.dm

@@ -18,9 +18,8 @@
 	..()
 	SSair.atmos_machinery += src
 
-	air_contents = new
+	air_contents = new(volume)
-	air_contents.volume = volume
+	air_contents.set_temperature(T20C)
-	air_contents.temperature = T20C
 
 	return 1
 

code/modules/atmospherics/machinery/portable/pump.dm

@@ -115,8 +115,8 @@
 		if("power")
 			on = !on
 			if(on && !holding)
-				var/plasma = air_contents.gases[/datum/gas/plasma]
+				var/plasma = air_contents.get_moles(/datum/gas/plasma)
-				var/n2o = air_contents.gases[/datum/gas/nitrous_oxide]
+				var/n2o = air_contents.get_moles(/datum/gas/nitrous_oxide)
 				if(n2o || plasma)
 					message_admins("[ADMIN_LOOKUPFLW(usr)] turned on a pump that contains [n2o ? "N2O" : ""][n2o && plasma ? " & " : ""][plasma ? "Plasma" : ""] at [ADMIN_VERBOSEJMP(src)]")
 					log_admin("[key_name(usr)] turned on a pump that contains [n2o ? "N2O" : ""][n2o && plasma ? " & " : ""][plasma ? "Plasma" : ""] at [AREACOORD(src)]")

code/modules/atmospherics/machinery/portable/scrubber.dm

@@ -40,20 +40,13 @@
 		scrub(T.return_air())
 
 /obj/machinery/portable_atmospherics/scrubber/proc/scrub(var/datum/gas_mixture/mixture)
-	var/transfer_moles = min(1, volume_rate / mixture.volume) * mixture.total_moles()
+	var/transfer_moles = min(1, volume_rate / mixture.return_volume()) * mixture.total_moles()
 
 	var/datum/gas_mixture/filtering = mixture.remove(transfer_moles) // Remove part of the mixture to filter.
-	var/datum/gas_mixture/filtered = new
 	if(!filtering)
 		return
 
-	filtered.temperature = filtering.temperature
+	filtering.scrub_into(air_contents,scrubbing)
-	for(var/gas in filtering.gases & scrubbing)
-		filtered.gases[gas] = filtering.gases[gas] // Shuffle the "bad" gasses to the filtered mixture.
-		filtering.gases[gas] = 0
-	GAS_GARBAGE_COLLECT(filtering.gases)
-
-	air_contents.merge(filtered) // Store filtered out gasses.
 	mixture.merge(filtering) // Returned the cleaned gas.
 	if(!holding)
 		air_update_turf()

code/modules/cargo/bounties/engineering.dm

@@ -10,9 +10,7 @@
 	if(!..())
 		return FALSE
 	var/obj/item/tank/T = O
-	if(!T.air_contents.gases[gas_type])
+	return T.air_contents.get_moles(gas_type) >= moles_required
-		return FALSE
-	return T.air_contents.gases[gas_type] >= moles_required
 
 //datum/bounty/item/engineering/gas/nitryl_tank
 //	name = "Full Tank of Nitryl"

code/modules/cargo/exports/large_objects.dm

@@ -169,15 +169,13 @@
 /datum/export/large/gas_canister/get_cost(obj/O)
 	var/obj/machinery/portable_atmospherics/canister/C = O
 	var/worth = 10
-	var/gases = C.air_contents.gases
+	worth += C.air_contents.get_moles(/datum/gas/bz)*3
-
+	worth += C.air_contents.get_moles(/datum/gas/stimulum)*25
-	worth += gases[/datum/gas/bz]*3
+	worth += C.air_contents.get_moles(/datum/gas/hypernoblium)*1000
-	worth += gases[/datum/gas/stimulum]*25
+	worth += C.air_contents.get_moles(/datum/gas/miasma)*2
-	worth += gases[/datum/gas/hypernoblium]*1000
+	worth += C.air_contents.get_moles(/datum/gas/tritium)*7
-	worth += gases[/datum/gas/miasma]*2
+	worth += C.air_contents.get_moles(/datum/gas/pluoxium)*6
-	worth += gases[/datum/gas/tritium]*7
+	worth += C.air_contents.get_moles(/datum/gas/nitryl)*30
-	worth += gases[/datum/gas/pluoxium]*6
-	worth += gases[/datum/gas/nitryl]*30
 	return worth
 
 

code/modules/events/spacevine.dm

@@ -171,10 +171,7 @@
 	var/turf/open/floor/T = holder.loc
 	if(istype(T))
 		var/datum/gas_mixture/GM = T.air
-		if(!GM.gases[/datum/gas/oxygen])
+		GM.set_moles(/datum/gas/oxygen, max(GM.get_moles(/datum/gas/oxygen) - severity * holder.energy, 0))
-			return
-		GM.gases[/datum/gas/oxygen] = max(GM.gases[/datum/gas/oxygen] - severity * holder.energy, 0)
-		GAS_GARBAGE_COLLECT(GM.gases)
 
 /datum/spacevine_mutation/nitro_eater
 	name = "nitrogen consuming"
@@ -186,10 +183,7 @@
 	var/turf/open/floor/T = holder.loc
 	if(istype(T))
 		var/datum/gas_mixture/GM = T.air
-		if(!GM.gases[/datum/gas/nitrogen])
+		GM.set_moles(/datum/gas/nitrogen, max(GM.get_moles(/datum/gas/nitrogen) - severity * holder.energy, 0))
-			return
-		GM.gases[/datum/gas/nitrogen] = max(GM.gases[/datum/gas/nitrogen] - severity * holder.energy, 0)
-		GAS_GARBAGE_COLLECT(GM.gases)
 
 /datum/spacevine_mutation/carbondioxide_eater
 	name = "CO2 consuming"
@@ -201,10 +195,7 @@
 	var/turf/open/floor/T = holder.loc
 	if(istype(T))
 		var/datum/gas_mixture/GM = T.air
-		if(!GM.gases[/datum/gas/carbon_dioxide])
+		GM.set_moles(/datum/gas/carbon_dioxide, max(GM.get_moles(/datum/gas/carbon_dioxide) - severity * holder.energy, 0))
-			return
-		GM.gases[/datum/gas/carbon_dioxide] = max(GM.gases[/datum/gas/carbon_dioxide] - severity * holder.energy, 0)
-		GAS_GARBAGE_COLLECT(GM.gases)
 
 /datum/spacevine_mutation/plasma_eater
 	name = "toxins consuming"
@@ -216,10 +207,7 @@
 	var/turf/open/floor/T = holder.loc
 	if(istype(T))
 		var/datum/gas_mixture/GM = T.air
-		if(!GM.gases[/datum/gas/plasma])
+		GM.set_moles(/datum/gas/plasma, max(GM.get_moles(/datum/gas/plasma) - severity * holder.energy, 0))
-			return
-		GM.gases[/datum/gas/plasma] = max(GM.gases[/datum/gas/plasma] - severity * holder.energy, 0)
-		GAS_GARBAGE_COLLECT(GM.gases)
 
 /datum/spacevine_mutation/thorns
 	name = "thorny"

code/modules/hydroponics/grown/misc.dm

@@ -57,8 +57,8 @@
 		return
 
 	var/datum/gas_mixture/stank = new
-	stank.gases[/datum/gas/miasma] = (yield + 6)*7*0.02 // this process is only being called about 2/7 as much as corpses so this is 12-32 times a corpses
+	stank.adjust_moles(/datum/gas/miasma,(yield + 6)*7*0.02) // this process is only being called about 2/7 as much as corpses so this is 12-32 times a corpses
-	stank.temperature = T20C // without this the room would eventually freeze and miasma mining would be easier
+	stank.set_temperature(T20C) // without this the room would eventually freeze and miasma mining would be easier
 	T.assume_air(stank)
 	T.air_update_turf()
 

code/modules/hydroponics/grown/towercap.dm

@@ -226,8 +226,8 @@
 	if(isopenturf(loc))
 		var/turf/open/O = loc
 		if(O.air)
-			var/loc_gases = O.air.gases
+			var/datum/gas_mixture/loc_air = O.air
-			if(loc_gases[/datum/gas/oxygen] > 13)
+			if(loc_air.get_moles(/datum/gas/oxygen) > 13)
 				return TRUE
 	return FALSE
 

code/modules/integrated_electronics/subtypes/atmospherics.dm

@@ -125,12 +125,12 @@
 		return
 
 	// Negative Kelvin temperatures should never happen and if they do, normalize them
-	if(source_air.temperature < TCMB)
+	if(source_air.return_temperature() < TCMB)
-		source_air.temperature = TCMB
+		source_air.set_temperature(TCMB)
 
 	var/pressure_delta = target_pressure - target_air.return_pressure()
 	if(pressure_delta > 0.1)
-		var/transfer_moles = (pressure_delta*target_air.volume/(source_air.temperature * R_IDEAL_GAS_EQUATION))*PUMP_EFFICIENCY
+		var/transfer_moles = (pressure_delta*target_air.return_volume()/(source_air.return_temperature() * R_IDEAL_GAS_EQUATION))*PUMP_EFFICIENCY
 		var/datum/gas_mixture/removed = source_air.remove(transfer_moles)
 		target_air.merge(removed)
 
@@ -171,14 +171,14 @@
 		return
 
 	// Negative Kelvin temperatures should never happen and if they do, normalize them
-	if(source_air.temperature < TCMB)
+	if(source_air.return_temperature() < TCMB)
-		source_air.temperature = TCMB
+		source_air.set_temperature(TCMB)
 
 	if((source_air.return_pressure() < 0.01) || (target_air.return_pressure() >= PUMP_MAX_PRESSURE))
 		return
 
 	//The second part of the min caps the pressure built by the volume pumps to the max pump pressure
-	var/transfer_ratio = min(transfer_rate,target_air.volume*PUMP_MAX_PRESSURE/source_air.return_pressure())/source_air.volume
+	var/transfer_ratio = min(transfer_rate,target_air.return_volume()*PUMP_MAX_PRESSURE/source_air.return_pressure())/source_air.return_volume()
 
 	var/datum/gas_mixture/removed = source_air.remove_ratio(transfer_ratio * PUMP_EFFICIENCY)
 
@@ -351,10 +351,10 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 	var/transfer_moles
 
 	//Negative Kelvins are an anomaly and should be normalized if encountered
-	if(source_air.temperature < TCMB)
+	if(source_air.return_temperature(TCMB))
-		source_air.temperature = TCMB
+		source_air.set_temperature(TCMB)
 
-	transfer_moles = (pressure_delta*contaminated_air.volume/(source_air.temperature * R_IDEAL_GAS_EQUATION))*PUMP_EFFICIENCY
+	transfer_moles = (pressure_delta*contaminated_air.return_volume()/(source_air.return_temperature() * R_IDEAL_GAS_EQUATION))*PUMP_EFFICIENCY
 
 	//If there is nothing to transfer, just return
 	if(transfer_moles <= 0)
@@ -368,16 +368,15 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 	//This is the gas that will be moved from source to filtered
 	var/datum/gas_mixture/filtered_out = new
 
-	for(var/filtered_gas in removed.gases)
+	for(var/filtered_gas in removed.get_gases())
 		//Get the name of the gas and see if it is in the list
 		if(GLOB.meta_gas_names[filtered_gas] in wanted)
 			//The gas that is put in all the filtered out gases
-			filtered_out.temperature = removed.temperature
+			filtered_out.set_temperature(removed.return_temperature())
-			filtered_out.gases[filtered_gas] = removed.gases[filtered_gas]
+			filtered_out.set_moles(filtered_gas, removed.get_moles(filtered_gas))
 
 			//The filtered out gas is entirely removed from the currently filtered gases
-			removed.gases[filtered_gas] = 0
+			removed.set_moles(filtered_gas, 0)
-			GAS_GARBAGE_COLLECT(removed.gases)
 
 	//Check if the pressure is high enough to put stuff in filtered, or else just put it back in the source
 	var/datum/gas_mixture/target = (filtered_air.return_pressure() < target_pressure ? filtered_air : source_air)
@@ -444,7 +443,7 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 	var/gas_percentage = round(max(min(get_pin_data(IC_INPUT, 4),100),0) / 100)
 
 	//Basically: number of moles = percentage of pressure filled up * efficiency coefficient * (pressure from both gases * volume of output) / (R * Temperature)
-	var/transfer_moles = (get_pin_data(IC_INPUT, 5) / max(1,output_gases.return_pressure())) * PUMP_EFFICIENCY * (source_1_gases.return_pressure() * gas_percentage +  source_2_gases.return_pressure() * (1 - gas_percentage)) * output_gases.volume/ (R_IDEAL_GAS_EQUATION * max(output_gases.temperature,TCMB))
+	var/transfer_moles = (get_pin_data(IC_INPUT, 5) / max(1,output_gases.return_pressure())) * PUMP_EFFICIENCY * (source_1_gases.return_pressure() * gas_percentage +  source_2_gases.return_pressure() * (1 - gas_percentage)) * output_gases.return_volume()/ (R_IDEAL_GAS_EQUATION * max(output_gases.return_temperature(),TCMB))
 
 
 	if(transfer_moles <= 0)
@@ -544,10 +543,10 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 	push_data()
 
 	//Cool the tank if the power is on and the temp is above
-	if(!power_draw_idle || air_contents.temperature < temperature)
+	if(!power_draw_idle || air_contents.return_temperature() < temperature)
 		return
 
-	air_contents.temperature = max(73.15,air_contents.temperature - (air_contents.temperature - temperature) * heater_coefficient)
+	air_contents.set_temperature(max(73.15,air_contents.return_temperature() - (air_contents.return_temperature() - temperature) * heater_coefficient))
 
 
 // - heater tank - // **works**
@@ -574,10 +573,10 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 	push_data()
 
 	//Heat the tank if the power is on or its temperature is below what is set
-	if(!power_draw_idle || air_contents.temperature > temperature)
+	if(!power_draw_idle || air_contents.return_temperature() > temperature)
 		return
 
-	air_contents.temperature = min(573.15,air_contents.temperature + (temperature - air_contents.temperature) * heater_coefficient)
+	air_contents.set_temperature(min(573.15,air_contents.return_temperature() + (temperature - air_contents.return_temperature()) * heater_coefficient))
 
 
 // - atmospheric cooler - // **works**
@@ -621,11 +620,11 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 		return
 
 	var/datum/gas_mixture/turf_air = current_turf.return_air()
-	if(!power_draw_idle || turf_air.temperature < temperature)
+	if(!power_draw_idle || turf_air.return_temperature() < temperature)
 		return
 
 	//Cool the gas
-	turf_air.temperature = max(243.15,turf_air.temperature - (turf_air.temperature - temperature) * heater_coefficient)
+	turf_air.set_temperature(max(243.15,turf_air.return_temperature() - (turf_air.return_temperature() - temperature) * heater_coefficient))
 
 
 // - atmospheric heater - // **works**
@@ -650,11 +649,11 @@ obj/item/integrated_circuit/atmospherics/connector/portableConnectorReturnAir()
 		return
 
 	var/datum/gas_mixture/turf_air = current_turf.return_air()
-	if(!power_draw_idle || turf_air.temperature > temperature)
+	if(!power_draw_idle || turf_air.return_temperature() > temperature)
 		return
 
 	//Heat the gas
-	turf_air.temperature = min(323.15,turf_air.temperature + (temperature - turf_air.temperature) * heater_coefficient)
+	turf_air.set_temperature(min(323.15,turf_air.return_temperature() + (temperature - turf_air.return_temperature()) * heater_coefficient))
 
 
 // - tank slot - // **works**

code/modules/integrated_electronics/subtypes/input.dm

@@ -1162,12 +1162,11 @@
 		activate_pin(3)
 		return
 
-	var/list/gases = air_contents.gases
 	var/list/gas_names = list()
 	var/list/gas_amounts = list()
-	for(var/id in gases)
+	for(var/id in air_contents.get_gases())
 		var/name = GLOB.meta_gas_names[id]
-		var/amt = round(gases[id], 0.001)
+		var/amt = round(air_contents.get_moles(id), 0.001)
 		gas_names.Add(name)
 		gas_amounts.Add(amt)
 
@@ -1175,7 +1174,7 @@
 	set_pin_data(IC_OUTPUT, 2, gas_amounts)
 	set_pin_data(IC_OUTPUT, 3, round(air_contents.total_moles(), 0.001))
 	set_pin_data(IC_OUTPUT, 4, round(air_contents.return_pressure(), 0.001))
-	set_pin_data(IC_OUTPUT, 5, round(air_contents.temperature, 0.001))
+	set_pin_data(IC_OUTPUT, 5, round(air_contents.return_temperature(), 0.001))
 	set_pin_data(IC_OUTPUT, 6, round(air_contents.return_volume(), 0.001))
 	push_data()
 	activate_pin(2)

code/modules/mapping/reader.dm

@@ -213,6 +213,7 @@
 	var/list/modelCache = build_cache(no_changeturf)
 	var/space_key = modelCache[SPACE_KEY]
 	var/list/bounds
+	var/did_expand = FALSE
 	src.bounds = bounds = list(1.#INF, 1.#INF, 1.#INF, -1.#INF, -1.#INF, -1.#INF)
 	var/datum/map_orientation_pattern/mode = forced_pattern || GLOB.map_orientation_patterns["[orientation]"] || GLOB.map_orientation_patterns["[SOUTH]"]
 	var/invert_y = mode.invert_y
@@ -235,6 +236,7 @@
 			else
 				while(parsed_z > world.maxz)
 					world.incrementMaxZ()
+					did_expand = TRUE
 			if(!no_changeturf)
 				WARNING("Z-level expansion occurred without no_changeturf set, this may cause problems when /turf/AfterChange is called")
 		//these values are the same until a new gridset is reached.
@@ -256,11 +258,13 @@
 						continue
 					else
 						world.maxx = placement_x
+						did_expand = TRUE
 				if(placement_y > world.maxy)
 					if(cropMap)
 						break
 					else
 						world.maxy = placement_y
+						did_expand = TRUE
 				if(placement_x < 1)
 					actual_x += xi
 					continue
@@ -301,6 +305,9 @@
 		testing("Skipped loading [turfsSkipped] default turfs")
 	#endif
 
+	if(did_expand)
+		world.refresh_atmos_grid()
+
 	return TRUE
 
 /datum/parsed_map/proc/build_cache(no_changeturf, bad_paths=null)

code/modules/mapping/space_management/multiz_helpers.dm

@@ -7,6 +7,20 @@
 		return get_step(SSmapping.get_turf_below(get_turf(ref)), dir)
 	return get_step(ref, dir)
 
+/proc/get_multiz_accessible_levels(center_z)
+	. = list(center_z)
+	var/other_z = center_z
+	var/offset
+	while((offset = SSmapping.level_trait(other_z, ZTRAIT_DOWN)))
+		other_z += offset
+		. += other_z
+	other_z = center_z
+	while((offset = SSmapping.level_trait(other_z, ZTRAIT_UP)))
+		other_z += offset
+		. += other_z
+	return .
+
+
 /proc/get_dir_multiz(turf/us, turf/them)
 	us = get_turf(us)
 	them = get_turf(them)
@@ -33,15 +47,3 @@
 /turf/proc/below()
 	return get_step_multiz(src, DOWN)
 	
-/proc/dir_inverse_multiz(dir)
-	var/holder = dir & (UP|DOWN)
-	if((holder == NONE) || (holder == (UP|DOWN)))
-		return turn(dir, 180)
-	dir &= ~(UP|DOWN)
-	dir = turn(dir, 180)
-	if(holder == UP)
-		holder = DOWN
-	else
-		holder = UP
-	dir |= holder
-	return dir

code/modules/mob/living/carbon/alien/life.dm

@@ -13,26 +13,23 @@
 
 	var/toxins_used = 0
 	var/tox_detect_threshold = 0.02
-	var/breath_pressure = (breath.total_moles()*R_IDEAL_GAS_EQUATION*breath.temperature)/BREATH_VOLUME
+	var/breath_pressure = (breath.total_moles()*R_IDEAL_GAS_EQUATION*breath.return_temperature())/BREATH_VOLUME
-	var/list/breath_gases = breath.gases
 
 	//Partial pressure of the toxins in our breath
-	var/Toxins_pp = (breath_gases[/datum/gas/plasma]/breath.total_moles())*breath_pressure
+	var/Toxins_pp = (breath.get_moles(/datum/gas/plasma)/breath.total_moles())*breath_pressure
 
 	if(Toxins_pp > tox_detect_threshold) // Detect toxins in air
-		adjustPlasma(breath_gases[/datum/gas/plasma]*250)
+		adjustPlasma(breath.get_moles(/datum/gas/plasma)*250)
 		throw_alert("alien_tox", /obj/screen/alert/alien_tox)
 
-		toxins_used = breath_gases[/datum/gas/plasma]
+		toxins_used = breath.get_moles(/datum/gas/plasma)
 
 	else
 		clear_alert("alien_tox")
 
 	//Breathe in toxins and out oxygen
-	breath_gases[/datum/gas/plasma] -= toxins_used
+	breath.adjust_moles(/datum/gas/plasma, -toxins_used)
-	breath_gases[/datum/gas/oxygen] += toxins_used
+	breath.adjust_moles(/datum/gas/oxygen, toxins_used)
-
-	GAS_GARBAGE_COLLECT(breath.gases)
 
 	//BREATH TEMPERATURE
 	handle_breath_temperature(breath)

code/modules/mob/living/carbon/human/species_types/plasmamen.dm

@@ -33,7 +33,7 @@
 	if((!istype(H.w_uniform, /obj/item/clothing/under/plasmaman) || !istype(H.head, /obj/item/clothing/head/helmet/space/plasmaman)) && !atmos_sealed)
 		if(environment)
 			if(environment.total_moles())
-				if(environment.gases[/datum/gas/oxygen] && (environment.gases[/datum/gas/oxygen]) >= 1) //Same threshhold that extinguishes fire
+				if(environment.get_moles(/datum/gas/oxygen) >= 1) //Same threshhold that extinguishes fire
 					H.adjust_fire_stacks(0.5)
 					if(!H.on_fire && H.fire_stacks > 0)
 						H.visible_message("<span class='danger'>[H]'s body reacts with the atmosphere and bursts into flames!</span>","<span class='userdanger'>Your body reacts with the atmosphere and bursts into flame!</span>")

code/modules/mob/living/carbon/life.dm

@@ -162,12 +162,11 @@
 	var/SA_para_min = 1
 	var/SA_sleep_min = 5
 	var/oxygen_used = 0
-	var/breath_pressure = (breath.total_moles()*R_IDEAL_GAS_EQUATION*breath.temperature)/BREATH_VOLUME
+	var/breath_pressure = (breath.total_moles()*R_IDEAL_GAS_EQUATION*breath.return_temperature())/BREATH_VOLUME
 
-	var/list/breath_gases = breath.gases
+	var/O2_partialpressure = (breath.get_moles(/datum/gas/oxygen)/breath.total_moles())*breath_pressure
-	var/O2_partialpressure = (breath_gases[/datum/gas/oxygen]/breath.total_moles())*breath_pressure
+	var/Toxins_partialpressure = (breath.get_moles(/datum/gas/plasma)/breath.total_moles())*breath_pressure
-	var/Toxins_partialpressure = (breath_gases[/datum/gas/plasma]/breath.total_moles())*breath_pressure
+	var/CO2_partialpressure = (breath.get_moles(/datum/gas/carbon_dioxide)/breath.total_moles())*breath_pressure
-	var/CO2_partialpressure = (breath_gases[/datum/gas/carbon_dioxide]/breath.total_moles())*breath_pressure
 
 
 	//OXYGEN
@@ -191,7 +190,7 @@
 			var/ratio = 1 - O2_partialpressure/safe_oxy_min
 			adjustOxyLoss(min(5*ratio, 3))
 			failed_last_breath = 1
-			oxygen_used = breath_gases[/datum/gas/oxygen]*ratio
+			oxygen_used = breath.get_moles(/datum/gas/oxygen)*ratio
 		else
 			adjustOxyLoss(3)
 			failed_last_breath = 1
@@ -203,12 +202,12 @@
 		o2overloadtime = 0 //reset our counter for this too
 		if(health >= crit_threshold)
 			adjustOxyLoss(-5)
-		oxygen_used = breath_gases[/datum/gas/oxygen]
+		oxygen_used = breath.get_moles(/datum/gas/oxygen)
 		clear_alert("not_enough_oxy")
 		SEND_SIGNAL(src, COMSIG_CLEAR_MOOD_EVENT, "suffocation")
 
-	breath_gases[/datum/gas/oxygen] -= oxygen_used
+	breath.adjust_moles(/datum/gas/oxygen, -oxygen_used)
-	breath_gases[/datum/gas/carbon_dioxide] += oxygen_used
+	breath.adjust_moles(/datum/gas/carbon_dioxide, oxygen_used)
 
 	//CARBON DIOXIDE
 	if(CO2_partialpressure > safe_co2_max)
@@ -227,15 +226,15 @@
 
 	//TOXINS/PLASMA
 	if(Toxins_partialpressure > safe_tox_max)
-		var/ratio = (breath_gases[/datum/gas/plasma]/safe_tox_max) * 10
+		var/ratio = (breath.get_moles(/datum/gas/plasma)/safe_tox_max) * 10
 		adjustToxLoss(clamp(ratio, MIN_TOXIC_GAS_DAMAGE, MAX_TOXIC_GAS_DAMAGE))
 		throw_alert("too_much_tox", /obj/screen/alert/too_much_tox)
 	else
 		clear_alert("too_much_tox")
 
 	//NITROUS OXIDE
-	if(breath_gases[/datum/gas/nitrous_oxide])
+	if(breath.get_moles(/datum/gas/nitrous_oxide))
-		var/SA_partialpressure = (breath_gases[/datum/gas/nitrous_oxide]/breath.total_moles())*breath_pressure
+		var/SA_partialpressure = (breath.get_moles(/datum/gas/nitrous_oxide)/breath.total_moles())*breath_pressure
 		if(SA_partialpressure > SA_para_min)
 			Unconscious(60)
 			if(SA_partialpressure > SA_sleep_min)
@@ -248,26 +247,26 @@
 		SEND_SIGNAL(src, COMSIG_CLEAR_MOOD_EVENT, "chemical_euphoria")
 
 	//BZ (Facepunch port of their Agent B)
-	if(breath_gases[/datum/gas/bz])
+	if(breath.get_moles(/datum/gas/bz))
-		var/bz_partialpressure = (breath_gases[/datum/gas/bz]/breath.total_moles())*breath_pressure
+		var/bz_partialpressure = (breath.get_moles(/datum/gas/bz)/breath.total_moles())*breath_pressure
 		if(bz_partialpressure > 1)
 			hallucination += 10
 		else if(bz_partialpressure > 0.01)
 			hallucination += 5
 
 	//TRITIUM
-	if(breath_gases[/datum/gas/tritium])
+	if(breath.get_moles(/datum/gas/tritium))
-		var/tritium_partialpressure = (breath_gases[/datum/gas/tritium]/breath.total_moles())*breath_pressure
+		var/tritium_partialpressure = (breath.get_moles(/datum/gas/tritium)/breath.total_moles())*breath_pressure
 		radiation += tritium_partialpressure/10
 
 	//NITRYL
-	if(breath_gases[/datum/gas/nitryl])
+	if(breath.get_moles(/datum/gas/nitryl))
-		var/nitryl_partialpressure = (breath_gases[/datum/gas/nitryl]/breath.total_moles())*breath_pressure
+		var/nitryl_partialpressure = (breath.get_moles(/datum/gas/nitryl)/breath.total_moles())*breath_pressure
 		adjustFireLoss(nitryl_partialpressure/4)
 
 	//MIASMA
-	if(breath_gases[/datum/gas/miasma])
+	if(breath.get_moles(/datum/gas/miasma))
-		var/miasma_partialpressure = (breath_gases[/datum/gas/miasma]/breath.total_moles())*breath_pressure
+		var/miasma_partialpressure = (breath.get_moles(/datum/gas/miasma)/breath.total_moles())*breath_pressure
 		if(miasma_partialpressure > MINIMUM_MOLES_DELTA_TO_MOVE)
 
 			if(prob(0.05 * miasma_partialpressure))
@@ -307,11 +306,6 @@
 	else
 		SEND_SIGNAL(src, COMSIG_CLEAR_MOOD_EVENT, "smell")
 
-
-
-
-	GAS_GARBAGE_COLLECT(breath.gases)
-
 	//BREATH TEMPERATURE
 	handle_breath_temperature(breath)
 
@@ -370,9 +364,9 @@
 
 	var/datum/gas_mixture/stank = new
 
-	stank.gases[/datum/gas/miasma] = 0.1
+	stank.set_moles(/datum/gas/miasma,0.1)
 
-	stank.temperature = BODYTEMP_NORMAL
+	stank.set_temperature(BODYTEMP_NORMAL)
 
 	miasma_turf.assume_air(stank)
 

code/modules/mob/living/carbon/monkey/life.dm

@@ -46,8 +46,8 @@
 	return ..()
 
 /mob/living/carbon/monkey/handle_breath_temperature(datum/gas_mixture/breath)
-	if(abs(BODYTEMP_NORMAL - breath.temperature) > 50)
+	if(abs(BODYTEMP_NORMAL - breath.return_temperature()) > 50)
-		switch(breath.temperature)
+		switch(breath.return_temperature())
 			if(-INFINITY to 120)
 				adjustFireLoss(3)
 			if(120 to 200)

code/modules/mob/living/life.dm

@@ -134,7 +134,7 @@
 		ExtinguishMob()
 		return
 	var/datum/gas_mixture/G = loc.return_air() // Check if we're standing in an oxygenless environment
-	if(G.gases[/datum/gas/oxygen] < 1)
+	if(G.get_moles(/datum/gas/oxygen, 1))
 		ExtinguishMob() //If there's no oxygen in the tile we're on, put out the fire
 		return
 	var/turf/location = get_turf(src)

code/modules/mob/living/living.dm

@@ -914,7 +914,7 @@
 	floating_need_update = TRUE
 
 /mob/living/proc/get_temperature(datum/gas_mixture/environment)
-	var/loc_temp = environment ? environment.temperature : T0C
+	var/loc_temp = environment ? environment.return_temperature() : T0C
 	if(isobj(loc))
 		var/obj/oloc = loc
 		var/obj_temp = oloc.return_temperature()

code/modules/mob/living/silicon/pai/software.dm

@@ -565,7 +565,6 @@
 		dat += "Unable to obtain a reading.<br>"
 	else
 		var/datum/gas_mixture/environment = T.return_air()
-		var/list/env_gases = environment.gases
 
 		var/pressure = environment.return_pressure()
 		var/total_moles = environment.total_moles()
@@ -573,11 +572,11 @@
 		dat += "Air Pressure: [round(pressure,0.1)] kPa<br>"
 
 		if (total_moles)
-			for(var/id in env_gases)
+			for(var/id in environment.get_gases())
-				var/gas_level = env_gases[id]/total_moles
+				var/gas_level = environment.get_moles(id)/total_moles
 				if(gas_level > 0.01)
 					dat += "[GLOB.meta_gas_names[id]]: [round(gas_level*100)]%<br>"
-		dat += "Temperature: [round(environment.temperature-T0C)]&deg;C<br>"
+		dat += "Temperature: [round(environment.return_temperature()-T0C)]&deg;C<br>"
 	dat += "<a href='byond://?src=[REF(src)];software=atmosensor;sub=0'>Refresh Reading</a> <br>"
 	dat += "<br>"
 	return dat

code/modules/mob/living/simple_animal/hostile/tree.dm

@@ -49,12 +49,12 @@
 		return
 	if(isopenturf(loc))
 		var/turf/open/T = src.loc
-		if(T.air && T.air.gases[/datum/gas/carbon_dioxide])
+		if(T.air)
-			var/co2 = T.air.gases[/datum/gas/carbon_dioxide]
+			var/co2 = T.air.get_moles(/datum/gas/carbon_dioxide)
 			if(co2 > 0)
 				if(prob(25))
 					var/amt = min(co2, 9)
-					T.air.gases[/datum/gas/carbon_dioxide] -= amt
+					T.air.adjust_moles(/datum/gas/carbon_dioxide, -amt)
 					T.atmos_spawn_air("o2=[amt]")
 
 /mob/living/simple_animal/hostile/tree/AttackingTarget()

code/modules/mob/living/simple_animal/simple_animal.dm

@@ -252,14 +252,11 @@
 	if(isturf(src.loc) && isopenturf(src.loc))
 		var/turf/open/ST = src.loc
 		if(ST.air)
-			var/ST_gases = ST.air.gases
 
-			var/tox = ST_gases[/datum/gas/plasma]
+			var/tox = ST.air.get_moles(/datum/gas/plasma)
-			var/oxy = ST_gases[/datum/gas/oxygen]
+			var/oxy = ST.air.get_moles(/datum/gas/oxygen)
-			var/n2  = ST_gases[/datum/gas/nitrogen]
+			var/n2  = ST.air.get_moles(/datum/gas/nitrogen)
-			var/co2 = ST_gases[/datum/gas/carbon_dioxide]
+			var/co2 = ST.air.get_moles(/datum/gas/carbon_dioxide)
-
-			GAS_GARBAGE_COLLECT(ST.air.gases)
 
 			if(atmos_requirements["min_oxy"] && oxy < atmos_requirements["min_oxy"])
 				. = FALSE

code/modules/mob/living/simple_animal/slime/life.dm

@@ -128,9 +128,7 @@
 		Tempstun = 0
 
 	if(stat != DEAD)
-		var/bz_percentage =0
+		var/bz_percentage = environment.total_moles() ? (environment.get_moles(/datum/gas/bz) / environment.total_moles()) : 0
-		if(environment.gases[/datum/gas/bz])
-			bz_percentage = environment.gases[/datum/gas/bz] / environment.total_moles()
 		var/stasis = (bz_percentage >= 0.05 && bodytemperature < (T0C + 100)) || force_stasis
 
 		if(stat == CONSCIOUS && stasis)