abms.lua: refactor and generalise run_pump_intake() to allow passing custom intake functions

new_flow_logic/abm_register.lua

@@ -24,13 +24,13 @@ register.balance = register_abm_balance
 
 -- register a node for the pump ABM.
 -- maxpressure is the maximum pressure that this pump can drive.
-local register_abm_input = function(nodename, maxpressure)
+local register_abm_input = function(nodename, maxpressure, intakefn)
 	minetest.register_abm({
 		nodenames = { nodename },
 		interval = 1,
 		chance = 1,
 		action = function(pos, node, active_object_count, active_object_count_wider)
-			pipeworks.flowlogic.run_pump_intake(pos, node, maxpressure)
+			pipeworks.flowlogic.run_input(pos, node, maxpressure, intakefn)
 		end
 	})
 end

new_flow_logic/abms.lua

@@ -31,12 +31,7 @@ end
 -- new version of liquid check
 -- accepts a limit parameter to only delete water blocks that the receptacle can accept,
 -- and returns it so that the receptacle can update it's pressure values.
--- this should ensure that water blocks aren't vanished from existance.
--- will take care of zero or negative-valued limits.
 local check_for_liquids_v2 = function(pos, limit)
-	if not limit then
-		limit = 6
-	end
 	local coords = make_coords_offsets(pos, false)
 	local total = 0
 	for index, tpos in ipairs(coords) do
@@ -89,15 +84,20 @@ end
 
 
 
-flowlogic.run_pump_intake = function(pos, node, maxpressure)
+flowlogic.run_input = function(pos, node, maxpressure, intakefn)
-	-- try to absorb nearby water nodes, but only up to limit.
+	-- intakefn allows a given input node to define it's own intake logic.
-	-- NB: check_for_liquids_v2 handles zero or negative from the following subtraction
+	-- this function will calculate the maximum amount of water that can be taken in;
+	-- the intakefn will be given this and is expected to return the actual absorption amount.
 
 	local meta = minetest.get_meta(pos)
 	local currentpressure = meta:get_float(label_pressure)
-	
 	local intake_limit = maxpressure - currentpressure
-	local actual_intake = check_for_liquids_v2(pos, intake_limit)
+	if intake_limit <= 0 then return end
+
+	local actual_intake = intakefn(pos, intake_limit)
+	if actual_intake <= 0 then return end
+	if actual_intake >= intake_limit then actual_intake = intake_limit end
+
 	local newpressure = actual_intake + currentpressure
 	-- debuglog("oldpressure "..currentpressure.." intake_limit "..intake_limit.." actual_intake "..actual_intake.." newpressure "..newpressure)
 	meta:set_float(label_pressure, newpressure)

new_flow_logic/flowable_node_registry.lua

@@ -51,7 +51,6 @@ local checkbase = function(nodename)
 end
 
 -- Register a node as a simple intake.
--- See new_flow_logic for the details of this.
 -- Expects node to be registered as a flowable (is present in flowables.list.all),
 -- so that water can move out of it.
 -- maxpressure is the maximum pipeline pressure that this node can drive.
@@ -61,6 +60,6 @@ register.intake_simple = function(nodename, maxpressure)
 	pipeworks.flowables.inputs.list[nodename] = { maxpressure=maxpressure }
 	table.insert(pipeworks.flowables.inputs.nodenames, nodename)
 	if pipeworks.enable_new_flow_logic then
-		abmregister.input(nodename, maxpressure)
+		abmregister.input(nodename, maxpressure, pipeworks.flowlogic.check_for_liquids_v2)
 	end
 end