Add a tool to insert network metadata into nodes

This also involves modifications of the network update routines
as the modification of metadata does not trigger the callbacks
used for this purpose.
Instead the tool manually forces updates to networks around the node.
Currently we cannot detect the digging of a node with specific
metadata associated, thus we currently need to trigger network updates
for ALL nodes digged which can incur much lag for heavy recalculations.

sparkcore/energy.lua

@@ -65,8 +65,8 @@ local function net_build(pos, callerpos, master_arg)
       local node = minetest.get_node(nodepos)
       local meta = minetest.get_meta(nodepos)
       local net_passive = minetest.get_item_group(node.name,"sparktech_net_passive")
-      if (not net_passive and meta:get_int("sparktech_net_passive") == 1) then
+      if (net_passive == 0 and meta:get_int("sparktech_net_passive") == 1) then
-        net_passive = true
+        net_passive = 1
       end
       local net_trigger = minetest.get_item_group(node.name,"sparktech_net_trigger")
       -- net passives are followed along to create the network (aka cables) but they do not get power,
@@ -86,7 +86,7 @@ local function net_build(pos, callerpos, master_arg)
 	-- Now the node shouldn’t be processed by the net_build anymore
 	processed[#processed + 1] = nodepos
       end
-      if (net_passive == 1 or ntrigontrig) then
+      if (net_passive ~= 0 or ntrigontrig) then
 		  net_build(nodepos, pos)
       end
     end
@@ -102,17 +102,22 @@ local function net_build(pos, callerpos, master_arg)
   return -- at this point all nodes have been processed, so we can return to the calling node
 end
 
-
+local function add_node(pos, newnode)
-minetest.register_on_placenode(function(pos, newnode, placer, oldnode, itemstack, pointed_thing)
+	local meta = minetest.get_meta(pos)
-  if (minetest.get_item_group(itemstack:get_name(), "sparktech_net_passive") == 1 ) then
+	if (minetest.get_item_group(newnode.name, "sparktech_net_passive") == 1 or meta:get_int("sparktech_net_passive") ~= 0) then
 		net_build(pos) -- only call this with none if the node really is not a trigger, otherwise the net will be build from it but it will not be contained
-  elseif (minetest.get_item_group(itemstack:get_name(), "sparktech_net_trigger") == 1 ) then
+	elseif (minetest.get_item_group(newnode.name, "sparktech_net_trigger") == 1 ) then
+		meta:set_string("net_master", nil)
 		net_build(pos, nil, pos)
 	end
+end
+
+minetest.register_on_placenode(function(pos, newnode, placer, oldnode, itemstack, pointed_thing)
+		add_node(pos, newnode)
 end)
 
-minetest.register_on_dignode(function(pos, oldnode, digger)
+local function remove_node(pos, oldnode, force)
-    if ((minetest.get_item_group(oldnode.name, "sparktech_net_passive") == 1) or (minetest.get_item_group(oldnode.name, "sparktech_net_trigger") == 1)) then
+	if (force or (minetest.get_item_group(oldnode.name, "sparktech_net_passive") == 1) or (minetest.get_item_group(oldnode.name, "sparktech_net_trigger") == 1)) then
 		local top = {x = pos.x, y = pos.y + 1, z = pos.z}
 		local bottom = {x = pos.x, y = pos.y - 1, z = pos.z}
 		local left = {x = pos.x - 1, y = pos.y, z = pos.z}
@@ -121,13 +126,14 @@ minetest.register_on_dignode(function(pos, oldnode, digger)
 		local back = {x = pos.x, y = pos.y, z = pos.z + 1}
 		for sidename, nodepos in pairs({top=top, bottom=bottom, left=left, right=right, front=front, back=back}) do
 			local target_node = minetest.get_node(nodepos)
-	local meta = minetest.get_meta(nodepos)
+			add_node(nodepos, target_node)
-	if (minetest.get_item_group(target_node.name, "sparktech_net_passive") == 1) then
-	  net_build(nodepos)
-	elseif (minetest.get_item_group(target_node.name, "sparktech_net_trigger") == 1) then
-	  meta:set_string("net_master", nil)
-	  net_build(nodepos, nil, nodepos)
-	end
 		end
     end
+end
+
+minetest.register_on_dignode(function(pos, oldnode, digger)
+		remove_node(pos, oldnode, true) -- FIXME Get rid of this! Somehow detect if a dynamic net_passive node is destroyed instead of updating speculatively
 end)
+
+sparktech.add_node_to_net = add_node
+sparktech.remove_node_from_net = remove_node

sparkwrench/cableinserter.lua

@@ -0,0 +1,33 @@
+local NAME = minetest.get_current_modname()
+
+minetest.register_tool(NAME .. ":cableinserter", {
+						   description = "Cable Inserter",
+						   inventory_image = "multimeter.png",
+						   stack_max = 1,
+						   on_place = function(itemstack, placer, pointed_thing)
+							   -- TODO Check that nodes does not already interact with the grid
+							   if pointed_thing["type"] == "node" then
+								   local node = minetest.get_node(pointed_thing.under)
+								   local meta = minetest.get_meta(pointed_thing.under)
+								   if meta:get_int("sparktech_net_passive") == 1 then
+									   meta:set_int("sparktech_net_passive", 0)
+									   sparktech.remove_node_from_net(pointed_thing.under, node, true)
+									   minetest.debug("Removed cable")
+								   else
+									   meta:set_int("sparktech_net_passive", 1)
+									   sparktech.add_node_to_net(pointed_thing.under, node)
+									   minetest.debug("Added cable")
+								   end
+							   end
+							   return itemstack
+						   end
+})
+
+minetest.register_craft({
+		output = NAME .. ":cableinserter",
+		recipe = {
+			{ "group:steelplate", "", "" },
+			{ "", "group:steelplate", "" },
+			{ "", "group:steelplate", ""},
+		}
+})