Increases performance significantly by turning garbage collection into a define

code/__DEFINES/atmospherics.dm

@@ -239,6 +239,8 @@
 
 //HELPERS
 #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)\
@@ -247,6 +249,14 @@
 		out_var += cached_gases[total_moles_id];\
 	}
 
+//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;\
+	for(var/id in CACHE_GAS){\
+		if(QUANTIZE(CACHE_GAS[id]) <= 0)\
+			CACHE_GAS -= id;\
+	}
+
 #define ARCHIVE_TEMPERATURE(gas) gas.temperature_archived = gas.temperature
 
 GLOBAL_LIST_INIT(pipe_paint_colors, list(