Made circulators and TEGs work, updated Rowtree's station with a functional powergrid and TEG battery.

Signed-off-by: SkyMarshal <skymarshal1729@gmail.com>

code/ATMOSPHERICS/components/binary_devices/circulator.dm

@@ -1,6 +1,14 @@
 //node1, air1, network1 correspond to input
 //node2, air2, network2 correspond to output
 
+#define CIRCULATOR_MIN_PRESSURE 10 //KPA to move the mechanism
+#define CIRCULATOR_VOLUME 100 //Litres
+#define CIRCULATOR_EFFICIENCY 0.65 //Out of 1.
+
+#define TURBINE_EFFICIENCY 0.1 //Uses more power than is generated.
+#define TURBINE_PRESSURE_DIFFERENCE 20 //Simulates a 20KPa difference
+#define GENRATE 800
+
 /obj/machinery/atmospherics/binary/circulator
 	name = "circulator/heat exchanger"
 	desc = "A gas circulator pump and heat exchanger."
@@ -11,13 +19,19 @@
 	//var/side = 1 // 1=left 2=right
 	var/status = 0
 
+	var/datum/gas_mixture/gas_contents
 	var/last_pressure_delta = 0
+	var/turbine_pumping = 0 //For when there is not enough pressure difference and we need to induce one or something.
+	var/last_power_generation = 0
 
 	density = 1
 
 /obj/machinery/atmospherics/binary/circulator/New()
 	..()
-	desc = initial(desc) + " Its outlet port is to the [dir2text(dir)]."
+	desc = initial(desc) + "  Its outlet port is to the [dir2text(dir)]."
+	gas_contents = new
+	gas_contents.volume = CIRCULATOR_VOLUME
+
 
 /obj/machinery/atmospherics/binary/circulator/proc/return_transfer_air()
 	if(!anchored)
@@ -25,40 +39,69 @@
 
 	var/output_starting_pressure = air2.return_pressure()
 	var/input_starting_pressure = air1.return_pressure()
+	var/internal_gas_pressure = gas_contents.return_pressure()
 
-	if(output_starting_pressure >= input_starting_pressure-10)
-		//Need at least 10 KPa difference to overcome friction in the mechanism
-		last_pressure_delta = 0
-		return null
+	var/intake_pressure_delta = input_starting_pressure - internal_gas_pressure
+	var/output_pressure_delta = internal_gas_pressure - output_starting_pressure
+
+	var/pressure_delta = max(intake_pressure_delta, output_pressure_delta, 0)
+
+	last_power_generation = 0
+	//If the turbine is running, we need to consider that.
+	if(turbine_pumping)
+		//Make it use powah
+		if(pressure_delta < TURBINE_PRESSURE_DIFFERENCE)
+			last_power_generation = (pressure_delta - TURBINE_PRESSURE_DIFFERENCE)*(1/TURBINE_EFFICIENCY)
+			pressure_delta = TURBINE_PRESSURE_DIFFERENCE
+
+		//If the force is already above what the turbine can do, shut it off and generate power instead!
+		else
+			turbine_pumping = 0
 
 	//Calculate necessary moles to transfer using PV = nRT
-	if(air1.temperature>0)
-		var/pressure_delta = (input_starting_pressure - output_starting_pressure)/2
+	if(air1.temperature > 0)
 
-		var/transfer_moles = pressure_delta*air2.volume/(air1.temperature * R_IDEAL_GAS_EQUATION)
+		var/transfer_moles = pressure_delta*gas_contents.volume/(air1.temperature * R_IDEAL_GAS_EQUATION)
 
 		last_pressure_delta = pressure_delta
 
-		//world << "pressure_delta = [pressure_delta]; transfer_moles = [transfer_moles];"
-
 		//Actually transfer the gas
-		var/datum/gas_mixture/removed = air1.remove(transfer_moles)
+		//Internal to output.
+		air2.merge(gas_contents.remove(transfer_moles))
 
+		//Intake to internal.
+		gas_contents.merge(air1.remove(transfer_moles))
+
+		//Update the gas networks.
 		if(network1)
 			network1.update = 1
 
 		if(network2)
 			network2.update = 1
 
-		return removed
-
 	else
 		last_pressure_delta = 0
 
+	//Needs at least 10 KPa difference to move the mechanism and make power
+	if(pressure_delta < CIRCULATOR_MIN_PRESSURE)
+		last_pressure_delta = 0
+
+	last_power_generation += pressure_delta*CIRCULATOR_EFFICIENCY
+
+	return gas_contents
+
+
+
+//Used by the TEG to know how much power to use/produce.
+/obj/machinery/atmospherics/binary/circulator/proc/ReturnPowerGeneration()
+	return GENRATE*last_power_generation
+
+
 /obj/machinery/atmospherics/binary/circulator/process()
 	..()
 	update_icon()
 
+
 /obj/machinery/atmospherics/binary/circulator/update_icon()
 	if(stat & (BROKEN|NOPOWER) || !anchored)
 		icon_state = "circ-p"
@@ -105,9 +148,9 @@
 	else
 		..()
 
-/obj/machinery/atmospherics/binary/circulator/verb/rotate()
+/obj/machinery/atmospherics/binary/circulator/verb/rotate_clockwise()
 	set category = "Object"
-	set name = "Rotate Circulator"
+	set name = "Rotate Circulator (Clockwise)"
 	set src in view(1)
 
 	if (usr.stat || usr.restrained() || anchored)
@@ -115,3 +158,15 @@
 
 	src.dir = turn(src.dir, 90)
 	desc = initial(desc) + " Its outlet port is to the [dir2text(dir)]."
+
+
+/obj/machinery/atmospherics/binary/circulator/verb/rotate_anticlockwise()
+	set category = "Object"
+	set name = "Rotate Circulator (Counterclockwise)"
+	set src in view(1)
+
+	if (usr.stat || usr.restrained() || anchored)
+		return
+
+	src.dir = turn(src.dir, -90)
+	desc = initial(desc) + " Its outlet port is to the [dir2text(dir)]."