Fix machines connected to multiple networks (#655)

Machines sometimes were be a part of multiple networks and generated power for each. This is fixed by checking if the machine is already part of an other network before assigning it to the current network.

technic/machines/register/cables.lua

@@ -43,17 +43,41 @@ local function check_connections(pos)
 	return connections
 end
 
-local function clear_networks(pos)
+local clear_networks
+
+local function clear_network(network_id)
+	if not network_id then
+		return
+	end
+
+	for _,v in pairs(technic.networks[network_id].all_nodes) do
+		local pos1 = minetest.hash_node_position(v)
+		technic.cables[pos1] = nil
+	end
+	local network_bckup = technic.networks[network_id]
+	technic.networks[network_id] = nil
+
+	for _,n_pos in pairs(network_bckup.PR_nodes) do
+		clear_networks(n_pos)
+	end
+	for _,n_pos in pairs(network_bckup.RE_nodes) do
+		clear_networks(n_pos)
+	end
+	for _,n_pos in pairs(network_bckup.BA_nodes) do
+		clear_networks(n_pos)
+	end
+end
+
+clear_networks = function(pos)
 	local node = minetest.get_node(pos)
 	local meta = minetest.get_meta(pos)
 	local placed = node.name ~= "air"
 	local positions = check_connections(pos)
+
 	if #positions < 1 then return end
-	local dead_end = #positions == 1
+
-	for _,connected_pos in pairs(positions) do
+	if #positions == 1 then
-		local net = technic.cables[minetest.hash_node_position(connected_pos)]
+		if placed then
-		if net and technic.networks[net] then
-			if dead_end and placed then
 			-- Dead end placed, add it to the network
 			-- Get the network
 			local network_id = technic.cables[minetest.hash_node_position(positions[1])]
@@ -61,22 +85,19 @@ local function clear_networks(pos)
 				-- We're evidently not on a network, nothing to add ourselves to
 				return
 			end
-				local sw_pos = minetest.get_position_from_hash(network_id)
-				sw_pos.y = sw_pos.y + 1
 			local network = technic.networks[network_id]
 			local tier = network.tier
 
 			-- Actually add it to the (cached) network
 			-- !! IMPORTANT: ../switching_station.lua -> check_node_subp() must be kept in sync
-				technic.cables[minetest.hash_node_position(pos)] = network_id
-				pos.visited = 1
 			if technic.is_tier_cable(node.name, tier) then
-					-- Found a cable
+				technic.cables[minetest.hash_node_position(pos)] = network_id
 				table.insert(network.all_nodes,pos)
 			elseif technic.machines[tier][node.name] then
 				-- Found a machine
 				local eu_type = technic.machines[tier][node.name]
 				meta:set_string(tier.."_network", string.format("%.20g", network_id))
+				meta:set_int(tier.."_EU_timeout", 2)
 				if     eu_type == technic.producer then
 					table.insert(network.PR_nodes, pos)
 				elseif eu_type == technic.receiver then
@@ -89,7 +110,7 @@ local function clear_networks(pos)
 				end
 				-- Note: SPECIAL (i.e. switching station) is not traversed!
 			end
-			elseif dead_end and not placed then
+		else
 			-- Dead end removed, remove it from the network
 			-- Get the network
 			local network_id = technic.cables[minetest.hash_node_position(positions[1])]
@@ -112,15 +133,16 @@ local function clear_networks(pos)
 					end
 				end
 			end
-			else
+		end
+		return
+	end
+
+	clear_network(technic.cables[minetest.hash_node_position(pos)])
+
+	for _,connected_pos in pairs(positions) do
+		local network_id = technic.cables[minetest.hash_node_position(connected_pos)]
 		-- Not a dead end, so the whole network needs to be recalculated
-				for _,v in pairs(technic.networks[net].all_nodes) do
+		clear_network(network_id)
-					local pos1 = minetest.hash_node_position(v)
-					technic.cables[pos1] = nil
-				end
-				technic.networks[net] = nil
-			end
-		end
 	end
 end
 
@@ -170,7 +192,7 @@ function technic.register_cable(tier, size)
 		connects_to = {"group:technic_"..ltier.."_cable",
 			"group:technic_"..ltier, "group:technic_all_tiers"},
 		on_construct = clear_networks,
-		on_destruct = clear_networks,
+		after_destruct = clear_networks,
 	})
 
 	local xyz = {
@@ -210,7 +232,7 @@ function technic.register_cable(tier, size)
 			connects_to = {"group:technic_"..ltier.."_cable",
 				"group:technic_"..ltier, "group:technic_all_tiers"},
 			on_construct = clear_networks,
-			on_destruct = clear_networks,
+			after_destruct = clear_networks,
 		}
 		def.node_box.fixed = {
 			{-size, -size, -size, size, size, size},

technic/machines/switching_station.lua

@@ -97,12 +97,14 @@ local function flatten(map)
 	return list
 end
 
--- Add a wire node to the LV/MV/HV network
+-- Add a node to the LV/MV/HV network
--- Returns: indicator whether the cable is new in the network
+-- Returns: indicator whether the node is new in the network
 local hash_node_position = minetest.hash_node_position
 local function add_network_node(nodes, pos, network_id)
 	local node_id = hash_node_position(pos)
+	if network_id then
 		technic.cables[node_id] = network_id
+	end
 	if nodes[node_id] then
 		return false
 	end
@@ -136,21 +138,31 @@ local check_node_subp = function(network, pos, machines, sw_pos, from_below, net
 	local meta = minetest.get_meta(pos)
 	-- Normal tostring() does not have enough precision, neither does meta:set_int()
 	-- Lua 5.1 bug: Cannot use hexadecimal notation for compression (see LuaJIT #911)
-	meta:set_string(network.tier.."_network", string.format("%.20g", network_id))
+	local network_str = string.format("%.20g", network_id)
+	local network_key = network.tier.."_network"
+	local m_network_str = meta:get_string(network_key)
+
+	if m_network_str == "" then
+		meta:set_string(network_key, network_str)
+	else
+		if m_network_str ~= network_str then
+			return
+		end
+	end
 
 	if     eu_type == technic.producer then
-		add_network_node(network.PR_nodes, pos, network_id)
+		add_network_node(network.PR_nodes, pos)
 	elseif eu_type == technic.receiver then
-		add_network_node(network.RE_nodes, pos, network_id)
+		add_network_node(network.RE_nodes, pos)
 	elseif eu_type == technic.producer_receiver then
-		add_network_node(network.PR_nodes, pos, network_id)
+		add_network_node(network.PR_nodes, pos)
-		add_network_node(network.RE_nodes, pos, network_id)
+		add_network_node(network.RE_nodes, pos)
 	elseif eu_type == technic.battery then
-		add_network_node(network.BA_nodes, pos, network_id)
+		add_network_node(network.BA_nodes, pos)
 	elseif eu_type == "SPECIAL" and from_below and
 			not vector.equals(pos, sw_pos) then
 		-- Another switching station -> disable it
-		add_network_node(network.SP_nodes, pos, network_id)
+		add_network_node(network.SP_nodes, pos)
 		meta:set_int("active", 0)
 	end
 
@@ -193,7 +205,6 @@ local get_network = function(sw_pos, cable_pos, tier)
 		end
 		return cached.PR_nodes, cached.BA_nodes, cached.RE_nodes
 	end
-
 	local machines = technic.machines[tier]
 	local network = {
 		tier = tier,
@@ -455,6 +466,7 @@ local function switching_station_timeout_count(pos, tier)
 	local meta = minetest.get_meta(pos)
 	local timeout = meta:get_int(tier.."_EU_timeout")
 	if timeout <= 0 then
+		meta:set_string(tier.."_network", "")
 		meta:set_int(tier.."_EU_input", 0) -- Not needed anymore <-- actually, it is for supply converter
 		return true
 	else