new flow logic: abms.lua: refactor flowlogic.run_output() into a processing stage of flowlogic.run()

new_flow_logic/abm_register.lua

@@ -66,6 +66,7 @@ register.input = register_abm_input
 -- threshold determines the minimum pressure, over which outputfn is called.
 -- outputfn is then given the current pressure, and returns the pressure relieved by the output process.
 -- outputfn is expected to update environment, nearby world etc. as appropriate for the node.
+--[[
 local register_abm_output = function(nodename, threshold, outputfn)
 	minetest.register_abm({
 		nodenames = { nodename },
@@ -77,6 +78,7 @@ local register_abm_output = function(nodename, threshold, outputfn)
 	})
 end
 register.output = register_abm_output
+]]
 
 -- old spigot ABM code, not yet migrated
 --[[

new_flow_logic/abms.lua

@@ -68,6 +68,7 @@ end
 
 
 flowlogic.run = function(pos, node)
+	local nodename = node.name
 	-- get the current pressure value.
 	local nodepressure = get_pressure_access(pos)
 	local currentpressure = nodepressure.get()
@@ -75,6 +76,18 @@ flowlogic.run = function(pos, node)
 	-- balance pressure with neighbours
 	currentpressure = flowlogic.balance_pressure(pos, node, currentpressure)
 
+	-- if node is an output: run output phase
+	local output = pipeworks.flowables.outputs.list[nodename]
+	if output then
+		currentpressure = flowlogic.run_output(
+			pos,
+			node,
+			currentpressure,
+			output.upper,
+			output.lower,
+			output.outputfn)
+	end
+
 	-- set the new pressure
 	nodepressure.set(currentpressure)
 end
@@ -176,20 +189,18 @@ end
 
 
 
-flowlogic.run_output = function(pos, node, threshold, outputfn)
+flowlogic.run_output = function(pos, node, currentpressure, upper, lower, outputfn)
-	-- callback for output devices.
+	-- processing step for water output devices.
-	-- takes care of checking a minimum pressure value and updating the node metadata.
+	-- takes care of checking a minimum pressure value and updating the resulting pressure level
 	-- the outputfn is provided the current pressure and returns the pressure "taken".
 	-- as an example, using this with the above spigot function,
 	-- the spigot function tries to output a water source if it will fit in the world.
-	local meta = minetest.get_meta(pos)
+	local result = currentpressure
-	-- sometimes I wonder if meta:get_* returning default values would ever be problematic.
+	if currentpressure > lower then
-	-- though here it doesn't matter, an uninit'd node returns 0, which is fine for a new, empty node.
-	local currentpressure = meta:get_float(label_pressure)
-	if currentpressure > threshold then
 		local takenpressure = outputfn(pos, node, currentpressure)
 		local newpressure = currentpressure - takenpressure
-		if newpressure < 0 then currentpressure = 0 end
+		if newpressure < 0 then newpressure = 0 end
-		meta:set_float(label_pressure, newpressure)
+		result = newpressure
 	end
+	return result
 end

new_flow_logic/flowable_node_registry_install.lua

@@ -75,10 +75,7 @@ register.output = function(nodename, upper, lower, outputfn)
 		error("pipeworks.flowables.outputs duplicate registration!")
 	end
 	checkbase(nodename)
-	pipeworks.flowables.outputs.list[nodename] = { threshold=threshold, outputfn=outputfn }
+	pipeworks.flowables.outputs.list[nodename] = { upper=upper, lower=lower, outputfn=outputfn }
-	if pipeworks.toggles.pressure_logic then
-		abmregister.output(nodename, lower, outputfn)
-	end
 	-- output ABM now part of main flow logic ABM to preserve ordering.
 	-- note that because outputs have to be a flowable first
 	-- (and the installation of the flow logic ABM is conditional),