Add overheating mechanics.

diode.lua

@@ -1,6 +1,8 @@
 -- © 2017 numberZero
 -- License: GNU Lesser General Public License, version 2 (or any later version)
 
+local OVERLOAD_THRESHOLD = 20.0
+
 local rules_in = {
 	[0] = {{x = -1, y = 0, z = 0}},
 	[1] = {{x = 0, y = 0, z = 1}},
@@ -24,6 +26,12 @@ local function diode_rules_out(node)
 end
 
 local function diode_action(pos, node, channel, msg)
+	if digiline_routing.overheat.heat(pos) > OVERLOAD_THRESHOLD then
+		digiline_routing.overheat.forget(pos)
+		minetest.dig_node(pos)
+		minetest.add_item(pos, node.name)
+		return
+	end
 	digiline:receptor_send(pos, diode_rules_out(node), channel, msg)
 end
 
@@ -45,6 +53,7 @@ minetest.register_node("digiline_routing:diode", {
 			{ -1/16, -8/16, -3/16, 1/16, -6/16, 3/16 },
 		},
 	},
+	on_destruct = digiline_routing.overheat.forget,
 	digiline = {
 		effector = {
                         action = diode_action,

init.lua

@@ -2,8 +2,10 @@
 -- License: GNU Lesser General Public License, version 2 (or any later version)
 -- License for textures: CreativeCommoms BY-ShareAlike
 
+digiline_routing = {}
+
 local MODNAME = "digiline_routing"
 local MODPATH = minetest.get_modpath(MODNAME)
 
--- dofile(MODPATH.."/overheating.lua")
+dofile(MODPATH.."/overheating.lua")
 dofile(MODPATH.."/diode.lua")

overheating.lua

@@ -0,0 +1,40 @@
+-- © 2017 numberZero
+-- License: GNU Lesser General Public License, version 2 (or any later version)
+
+local COOLDOWN_STEP = 0.5
+local DEFAULT_MAX_RATE = 20.0
+local hot_objects = {}
+local timer = 0.0
+
+digiline_routing.overheat = {}
+
+digiline_routing.overheat.heat = function(pos, heat)
+	local id = minetest.hash_node_position(pos)
+	local temperature = (hot_objects[id] or 0) + (heat or 1)
+	hot_objects[id] = temperature
+	return temperature
+end
+
+digiline_routing.overheat.forget = function(pos)
+	local id = minetest.hash_node_position(pos)
+	hot_objects[id] = nil
+end
+
+local global_cooldown = function(dtime)
+	timer = timer + dtime
+	if timer < COOLDOWN_STEP then -- don't overload the CPU
+		return
+	end
+	local cooldown = DEFAULT_MAX_RATE * timer
+	timer = 0
+	for id, temperature in pairs(hot_objects) do
+		temperature = temperature - cooldown
+		if temperature <= 0 then
+			hot_objects[id] = nil
+		else
+			hot_objects[id] = temperature
+		end
+	end
+end
+
+minetest.register_globalstep(global_cooldown)