fix wireless pos comparison and update jammer, there might be a possibility to somehow cause a not ending loop

moremesecons_wireless/init.lua

@@ -3,42 +3,47 @@ local JAMMER_MAX_DISTANCE = 15
 local wireless = {}
 local wireless_rids = {}
 
+-- localize these functions with small names because they work fairly fast
+local get = vector.get_data_from_pos
+local set = vector.set_data_to_pos
+local remove = vector.remove_data_from_pos
 
-local register = function(pos)
-	local RID = vector.get_data_from_pos(wireless_rids, pos.z,pos.y,pos.x)
-	if not RID then
-		table.insert(wireless, pos)
-		vector.set_data_to_pos(wireless_rids, pos.z,pos.y,pos.x, #wireless)
+-- if the wireless at pos isn't stored yet, put it into the tables
+local function register_RID(pos)
+	if get(wireless_rids, pos.z,pos.y,pos.x) then
+		return
+	end
+	local RID = #wireless+1
+	wireless[RID] = pos
+	set(wireless_rids, pos.z,pos.y,pos.x, RID)
+end
+
+local is_jammed
+local function wireless_activate(pos)
+	if is_jammed(pos) then
+		-- jamming doesn't disallow receiving signals, only sending them
+		return
+	end
+	local channel_first_wireless = minetest.get_meta(pos):get_string("channel")
+	for i = 1, #wireless do
+		if not vector.equals(wireless[i], pos)
+		and minetest.get_meta(wireless[i]):get_string("channel") == channel_first_wireless then
+			mesecon.receptor_on(wireless[i])
+		end
 	end
 end
 
-local wireless_activate = function(pos)
-	if not minetest.registered_nodes["moremesecons_wireless:wireless"] then return end
-	local channel_first_wireless = nil
-	
+local function wireless_deactivate(pos)
+	if is_jammed(pos) then
+		return
+	end
+	local channel_first_wireless = minetest.get_meta(pos):get_string("channel")
 	for i = 1, #wireless do
-		meta = minetest.get_meta(pos)
-		channel_first_wireless = meta:get_string("channel")
-		meta = minetest.get_meta(wireless[i])
-		if wireless[i] ~= pos and meta:get_string("channel") == channel_first_wireless and not minetest.find_node_near(pos, JAMMER_MAX_DISTANCE, {"moremesecons_wireless:jammer_on"}) then
-			mesecon.receptor_on(wireless[i])
-		end
-	end	
-end
-
-local wireless_deactivate = function(pos)
-	if not minetest.registered_nodes["moremesecons_wireless:wireless"] then return end
-	local meta = minetest.get_meta(pos)
-	local channel_first_wireless = nil
-	
-	for i = 1, #wireless do
-		meta = minetest.get_meta(pos)
-		channel_first_wireless = meta:get_string("channel")
-		meta = minetest.get_meta(wireless[i])
-		if wireless[i] ~= pos and meta:get_string("channel") == channel_first_wireless and not minetest.find_node_near(pos, JAMMER_MAX_DISTANCE, {"moremesecons_wireless:jammer_on"}) then
+		if not vector.equals(wireless[i], pos)
+		and minetest.get_meta(wireless[i]):get_string("channel") == channel_first_wireless then
 			mesecon.receptor_off(wireless[i])
 		end
-	end	
+	end
 end
 
 minetest.register_node("moremesecons_wireless:wireless", {
@@ -56,10 +61,10 @@ minetest.register_node("moremesecons_wireless:wireless", {
 	on_construct = function(pos)
 		local meta = minetest.get_meta(pos)
    		meta:set_string("formspec", "field[channel;channel;${channel}]")
-   		register(pos)
+   		register_RID(pos)
 	end,
 	on_destruct = function(pos)
-		local RID = vector.get_data_from_pos(wireless_rids, pos.z,pos.y,pos.x)
+		local RID = get(wireless_rids, pos.z,pos.y,pos.x)
 		if RID then
 			table.remove(wireless, RID)
 			vector.remove_data_from_pos(wireless_rids, pos.z,pos.y,pos.x)
@@ -71,6 +76,38 @@ minetest.register_node("moremesecons_wireless:wireless", {
 	end,
 })
 
+local jammers = {}
+local function add_jammer(pos)
+	if get(jammers, pos.z,pos.y,pos.x) then
+		return
+	end
+	set(jammers, pos.z,pos.y,pos.x, true)
+end
+
+local function remove_jammer(pos)
+	remove(jammers, pos.z,pos.y,pos.x)
+end
+
+-- looks big, but should work fast
+function is_jammed(pos)
+	local pz,py,px = vector.unpack(pos)
+	for z,yxs in pairs(jammers) do
+		if math.abs(pz-z) <= JAMMER_MAX_DISTANCE then
+			for y,xs in pairs(yxs) do
+				if math.abs(py-y) <= JAMMER_MAX_DISTANCE then
+					for x in pairs(xs) do
+						if math.abs(px-x) <= JAMMER_MAX_DISTANCE
+						and (px-x)^2+(py-y)^2+(pz-z)^2 <= JAMMER_MAX_DISTANCE^2 then
+							return true
+						end
+					end
+				end
+			end
+		end
+	end
+	return false
+end
+
 mesecon.register_node("moremesecons_wireless:jammer", {
 	description="Wireless Jammer",
 	paramtype = "light",
@@ -79,16 +116,21 @@ mesecon.register_node("moremesecons_wireless:jammer", {
 	groups = {dig_immediate=2},
 	mesecons = {effector = {
 		action_on = function(pos)
-			table.foreach(pos, print)
+			add_jammer(pos)
 			minetest.swap_node(pos, {name="moremesecons_wireless:jammer_on"})
-		end }}
+		end
+	}}
 },{
 	tiles = {"moremesecons_jammer_on.png"},
 	groups = {dig_immediate=2, not_in_creative_inventory=1},
 	mesecons = {effector = {
 		action_off = function(pos)
+			remove_jammer(pos)
 			minetest.swap_node(pos, {name="moremesecons_wireless:jammer_off"})
-		end }}
+		end
+	}},
+	on_destruct = remove_jammer,
+	on_construct = add_jammer,
 })
 
 minetest.register_craft({
@@ -108,8 +150,15 @@ minetest.register_craft({
 })
 
 minetest.register_abm({
-	nodenames = {"moremesecons_wireless:wireless"},
-	interval=1,
-	chance=1,
-	action = register
+	nodenames = {"moremesecons_wireless:jammer_on"},
+	interval = 5,
+	chance = 1,
+	action = add_jammer
+})
+
+minetest.register_abm({
+	nodenames = {"moremesecons_wireless:wireless"},
+	interval = 5,
+	chance = 1,
+	action = register_RID
 })