Make modpack mostly independent from MTG (#607)

mesecons_extrawires/mesewire.lua

@@ -1,3 +1,20 @@
+local mese_nodename = minetest.registered_aliases["mesecons_gamecompat:mese"]
+if mese_nodename then
+	-- Convert placeholders.
+	minetest.register_alias("mesecons_extrawires:mese", mese_nodename)
+else
+	-- Register placeholder.
+	mese_nodename = "mesecons_extrawires:mese"
+	minetest.register_node("mesecons_extrawires:mese", {
+		description = "Mese Wire",
+		tiles = {"mesecons_wire_off.png"},
+		paramtype = "light",
+		light_source = 3,
+		groups = {cracky = 1},
+		sounds = mesecon.node_sound.stone,
+	})
+end
+
 local mesewire_rules =
 {
 	{x = 1, y = 0, z = 0},
@@ -8,7 +25,7 @@ local mesewire_rules =
 	{x = 0, y = 0, z =-1},
 }
 
-minetest.override_item("default:mese", {
+minetest.override_item(mese_nodename, {
 	mesecons = {conductor = {
 		state = mesecon.state.off,
 		onstate = "mesecons_extrawires:mese_powered",
@@ -18,15 +35,17 @@ minetest.override_item("default:mese", {
 
 -- Copy node definition of powered mese from normal mese
 -- and brighten texture tiles to indicate mese is powered
-local powered_def = mesecon.merge_tables(minetest.registered_nodes["default:mese"], {
-	drop = "default:mese",
-	light_source = 5,
+local unpowered_def = minetest.registered_nodes[mese_nodename]
+local powered_def = mesecon.merge_tables(unpowered_def, {
+	drop = mese_nodename,
+	paramtype = "light",
+	light_source = math.min(unpowered_def.light_source + 2, minetest.LIGHT_MAX),
 	mesecons = {conductor = {
 		state = mesecon.state.on,
-		offstate = "default:mese",
+		offstate = mese_nodename,
 		rules = mesewire_rules
 	}},
-	groups = {cracky = 1, not_in_creative_inventory = 1},
+	groups = mesecon.merge_tables(unpowered_def.groups or {}, {not_in_creative_inventory = 1}),
 	on_blast = mesecon.on_blastnode,
 })