Committed atmospheric pipe tests

Code/Machinery/vent.dm

@@ -93,8 +93,96 @@ obj/machinery/vent
 
 
 
+obj/machinery/emergencyrelease
 
 
+	name = "vent"
+	icon = 'pipes.dmi'
+	icon_state = "vent"
+	desc = "An emergency release vent.  Releases at 133% suggested mass content."
+	anchored = 1
+	p_dir = 2
+	capmult = 2
+
+	var
+		obj/machinery/node				// the connected object
+		obj/machinery/vnode			// the connected pipeline (if node is a pipe)
+		obj/substance/gas/gas			// the gas reservoir
+		obj/substance/gas/ngas			// the new gas reservoir after calculating flow
+		capacity = 6000000				// nominal gas capacity
+
+
+	// Create a new vent. Pipe connection p_dir is calculated from icon dir, so p_dir does not need to be set on map.
+	// Create the gas reservoir and register with the gasflowlist.
+
+	New()
+		..()
+		p_dir = dir
+		gas = new/obj/substance/gas(src)
+		gas.maximum = capacity
+		ngas = new/obj/substance/gas()
+		gasflowlist += src
+
+
+	// Find the connected machine or pipe to the vent pipe.
+
+	buildnodes()
+		var/turf/T = get_step(src.loc, src.dir)
+		var/fdir = turn(src.p_dir, 180)
+
+		for(var/obj/machinery/M in T)
+			if(M.p_dir & fdir)
+				src.node = M
+				break
+
+		if(node) vnode = node.getline()
+
+		return
+
+
+	// Get the gas fullness value.
+
+	get_gas_val(from)
+		return gas.tot_gas()/2
+
+	// Get the gas reservoir object
+
+	get_gas(from)
+		return gas
+
+
+	// Replace the gas level by the new level calculated in process()
+
+	gas_flow()
+		gas.replace_by(ngas)
+
+
+	// Timed process. Dump gas into turf, then do standard flow calc for connected pipe.
+
+	process()
+
+		var/delta_gt
+
+		var/turf/T = src.loc
+
+		if(gas.tot_gas() >= gas.maximum * 1.3)
+
+			delta_gt = FLOWFRAC * (gas.tot_gas() / capmult)
+			ngas.turf_add(T, delta_gt)
+			if(vnode)
+				delta_gt = FLOWFRAC * ( vnode.get_gas_val(src) - gas.tot_gas() / capmult)
+				calc_delta( src, gas, ngas, vnode, delta_gt)//, dbg)
+			else
+				leak_to_turf()
+
+
+	// Leak from pipe to turf if no node connected
+
+	proc/leak_to_turf()
+
+		var/turf/T = get_step(src, dir)
+		if(T && !T.density)
+			flow_to_turf(gas, ngas, T)