Add lua controlled tube (#199)

* add lua controlled tube

* make textures and fix some bugs

9 files changed, 1049 insertions, 2 deletions

diff --git a/LICENSE b/LICENSE
index 4362b49..ecbf212 100644
--- a/LICENSE
+++ b/LICENSE
@@ -500,3 +500,194 @@ necessary.  Here is a sample; alter the names:
   Ty Coon, President of Vice
 
 That's all there is to it!
+
+
+--------------------------------------------------------------------------------
+
+Some code in lua_tube.lua is copied from The Mesecons Mod for Minetest:
+
+License of source code
+----------------------
+Copyright (C) 2011-2016 Mesecons Mod Developer Team and contributors
+
+This program is free software; you can redistribute the Mesecons Mod and/or
+modify it under the terms of the GNU Lesser General Public License version 3
+published by the Free Software Foundation.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with this library; if not, write to the
+Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
+Boston, MA  02110-1301, USA.
+
+
+GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
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+with which the Combined Work was made is also called the "Linked
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+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
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+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
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+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
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+   b) under the GNU GPL, with none of the additional permissions of
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+  3. Object Code Incorporating Material from Library Header Files.
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+   a) Accompany the combined library with a copy of the same work based
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+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
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+  6. Revised Versions of the GNU Lesser General Public License.
+
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+
diff --git a/default_settings.lua b/default_settings.lua
index f027461..91e511c 100644
--- a/default_settings.lua
+++ b/default_settings.lua
@@ -22,6 +22,7 @@ local settings = {
 	enable_mese_sand_tube = true,
 	enable_one_way_tube = true,
 	enable_priority_tube = true,
+	enable_lua_tube = true,
 	enable_cyclic_mode = true,
 	drop_on_routing_fail = false,
 
diff --git a/init.lua b/init.lua
index 1a330e5..2e05337 100644
--- a/init.lua
+++ b/init.lua
@@ -119,6 +119,7 @@ if pipeworks.enable_redefines then
 	dofile(pipeworks.modpath.."/compat-furnaces.lua")
 end
 if pipeworks.enable_autocrafter then dofile(pipeworks.modpath.."/autocrafter.lua") end
+if pipeworks.enable_lua_tube then dofile(pipeworks.modpath.."/lua_tube.lua") end
 
 minetest.register_alias("pipeworks:pipe", "pipeworks:pipe_110000_empty")
 
diff --git a/lua_tube.lua b/lua_tube.lua
new file mode 100644
index 0000000..51665ae
--- /dev/null
+++ b/lua_tube.lua
@@ -0,0 +1,850 @@
+--        ______
+--       |
+--       |
+--       |        __       ___  _   __         _  _
+-- |   | |       |  | |\ |  |  |_| |  | |  |  |_ |_|
+-- |___| |______ |__| | \|  |  | \ |__| |_ |_ |_ |\  tube
+-- |
+-- |
+--
+
+-- Reference
+-- ports = get_real_port_states(pos): gets if inputs are powered from outside
+-- newport = merge_port_states(state1, state2): just does result = state1 or state2 for every port
+-- set_port(pos, rule, state): activates/deactivates the mesecons according to the port states
+-- set_port_states(pos, ports): Applies new port states to a Luacontroller at pos
+-- run(pos): runs the code in the controller at pos
+-- reset_meta(pos, code, errmsg): performs a software-reset, installs new code and prints error messages
+-- resetn(pos): performs a hardware reset, turns off all ports
+--
+-- The Sandbox
+-- The whole code of the controller runs in a sandbox,
+-- a very restricted environment.
+-- Actually the only way to damage the server is to
+-- use too much memory from the sandbox.
+-- You can add more functions to the environment
+-- (see where local env is defined)
+-- Something nice to play is is appending minetest.env to it.
+
+local BASENAME = "pipeworks:lua_tube"
+
+local rules = {
+	red    = {x = -1, y =  0, z =  0, name = "red"},
+	blue   = {x =  1, y =  0, z =  0, name = "blue"},
+	yellow = {x =  0, y = -1, z =  0, name = "yellow"},
+	green  = {x =  0, y =  1, z =  0, name = "green"},
+	black  = {x =  0, y =  0, z = -1, name = "black"},
+	white  = {x =  0, y =  0, z =  1, name = "white"},
+}
+
+
+------------------
+-- Action stuff --
+------------------
+-- These helpers are required to set the port states of the lua_tube
+
+local function update_real_port_states(pos, rule_name, new_state)
+	local meta = minetest.get_meta(pos)
+	if rule_name == nil then
+		meta:set_int("real_portstates", 1)
+		return
+	end
+	local n = meta:get_int("real_portstates") - 1
+	local L = {}
+	for i = 1, 6 do
+		L[i] = n % 2
+		n = math.floor(n / 2)
+	end
+	--                  (0,0,-1) (0,-1,0) (-1,0,0)      (1,0,0) (0,1,0) (0,0,1)
+	local pos_to_side = {  5,        3,       1,   nil,    2,      4,      6  }
+	if rule_name.x == nil then
+		for _, rname in ipairs(rule_name) do
+			local port = pos_to_side[rname.x + (2 * rname.y) + (3 * rname.z) + 4]
+			L[port] = (newstate == "on") and 1 or 0
+		end
+	else
+		local port = pos_to_side[rule_name.x + (2 * rule_name.y) + (3 * rule_name.z) + 4]
+		L[port] = (new_state == "on") and 1 or 0
+	end
+	meta:set_int("real_portstates",
+		 1 +
+		 1 * L[1] +
+		 2 * L[2] +
+		 4 * L[3] +
+		 8 * L[4] +
+		16 * L[5] +
+		32 * L[6])
+end
+
+
+local port_names = {"red", "blue", "yellow", "green", "black", "white"}
+
+local function get_real_port_states(pos)
+	-- Determine if ports are powered (by itself or from outside)
+	local meta = minetest.get_meta(pos)
+	local L = {}
+	local n = meta:get_int("real_portstates") - 1
+	for _, name in ipairs(port_names) do
+		L[name] = ((n % 2) == 1)
+		n = math.floor(n / 2)
+	end
+	return L
+end
+
+
+local function merge_port_states(ports, vports)
+	return {
+		red    = ports.red    or vports.red,
+		blue   = ports.blue   or vports.blue,
+		yellow = ports.yellow or vports.yellow,
+		green  = ports.green  or vports.green,
+		black  = ports.black  or vports.black,
+		white  = ports.white  or vports.white,
+	}
+end
+
+local function generate_name(ports)
+	local red    = ports.red    and 1 or 0
+	local blue   = ports.blue   and 1 or 0
+	local yellow = ports.yellow and 1 or 0
+	local green  = ports.green  and 1 or 0
+	local black  = ports.black  and 1 or 0
+	local white  = ports.white  and 1 or 0
+	return BASENAME..white..black..green..yellow..blue..red
+end
+
+
+local function set_port(pos, rule, state)
+	if state then
+		mesecon.receptor_on(pos, {rule})
+	else
+		mesecon.receptor_off(pos, {rule})
+	end
+end
+
+
+local function clean_port_states(ports)
+	ports.red    = ports.red    and true or false
+	ports.blue   = ports.blue   and true or false
+	ports.yellow = ports.yellow and true or false
+	ports.green  = ports.green  and true or false
+	ports.black  = ports.black  and true or false
+	ports.white  = ports.white  and true or false
+end
+
+
+local function set_port_states(pos, ports)
+	local node = minetest.get_node(pos)
+	local name = node.name
+	clean_port_states(ports)
+	local vports = minetest.registered_nodes[name].virtual_portstates
+	local new_name = generate_name(ports)
+
+	if name ~= new_name and vports then
+		-- Problem:
+		-- We need to place the new node first so that when turning
+		-- off some port, it won't stay on because the rules indicate
+		-- there is an onstate output port there.
+		-- When turning the output off then, it will however cause feedback
+		-- so that the lua_tube will receive an "off" event by turning
+		-- its output off.
+		-- Solution / Workaround:
+		-- Remember which output was turned off and ignore next "off" event.
+		local meta = minetest.get_meta(pos)
+		local ign = minetest.deserialize(meta:get_string("ignore_offevents")) or {}
+		if ports.red    and not vports.red    and not mesecon.is_powered(pos, rules.red)    then ign.red    = true end
+		if ports.blue   and not vports.blue   and not mesecon.is_powered(pos, rules.blue)   then ign.blue   = true end
+		if ports.yellow and not vports.yellow and not mesecon.is_powered(pos, rules.yellow) then ign.yellow = true end
+		if ports.green  and not vports.green  and not mesecon.is_powered(pos, rules.green)  then ign.green  = true end
+		if ports.black  and not vports.black  and not mesecon.is_powered(pos, rules.black)  then ign.black  = true end
+		if ports.white  and not vports.white  and not mesecon.is_powered(pos, rules.white)  then ign.white  = true end
+		meta:set_string("ignore_offevents", minetest.serialize(ign))
+
+		minetest.swap_node(pos, {name = new_name, param2 = node.param2})
+
+		if ports.red    ~= vports.red    then set_port(pos, rules.red,    ports.red)    end
+		if ports.blue   ~= vports.blue   then set_port(pos, rules.blue,   ports.blue)   end
+		if ports.yellow ~= vports.yellow then set_port(pos, rules.yellow, ports.yellow) end
+		if ports.green  ~= vports.green  then set_port(pos, rules.green,  ports.green)  end
+		if ports.black  ~= vports.black  then set_port(pos, rules.black,  ports.black)  end
+		if ports.white  ~= vports.white  then set_port(pos, rules.white,  ports.white)  end
+	end
+end
+
+
+-----------------
+-- Overheating --
+-----------------
+local function burn_controller(pos)
+	local node = minetest.get_node(pos)
+	node.name = BASENAME.."_burnt"
+	minetest.swap_node(pos, node)
+	minetest.get_meta(pos):set_string("lc_memory", "");
+	-- Wait for pending operations
+	minetest.after(0.2, mesecon.receptor_off, pos, mesecon.rules.flat)
+end
+
+local function overheat(pos, meta)
+	if mesecon.do_overheat(pos) then -- If too hot
+		burn_controller(pos)
+		return true
+	end
+end
+
+------------------------
+-- Ignored off events --
+------------------------
+
+local function ignore_event(event, meta)
+	if event.type ~= "off" then return false end
+	local ignore_offevents = minetest.deserialize(meta:get_string("ignore_offevents")) or {}
+	if ignore_offevents[event.pin.name] then
+		ignore_offevents[event.pin.name] = nil
+		meta:set_string("ignore_offevents", minetest.serialize(ignore_offevents))
+		return true
+	end
+end
+
+-------------------------
+-- Parsing and running --
+-------------------------
+
+local function safe_print(param)
+	print(dump(param))
+end
+
+local function safe_date()
+	return(os.date("*t",os.time()))
+end
+
+-- string.rep(str, n) with a high value for n can be used to DoS
+-- the server. Therefore, limit max. length of generated string.
+local function safe_string_rep(str, n)
+	if #str * n > mesecon.setting("luacontroller_string_rep_max", 64000) then
+		debug.sethook() -- Clear hook
+		error("string.rep: string length overflow", 2)
+	end
+
+	return string.rep(str, n)
+end
+
+-- string.find with a pattern can be used to DoS the server.
+-- Therefore, limit string.find to patternless matching.
+local function safe_string_find(...)
+	if (select(4, ...)) ~= true then
+		debug.sethook() -- Clear hook
+		error("string.find: 'plain' (fourth parameter) must always be true in a lua controlled tube")
+	end
+
+	return string.find(...)
+end
+
+local function remove_functions(x)
+	local tp = type(x)
+	if tp == "function" then
+		return nil
+	end
+
+	-- Make sure to not serialize the same table multiple times, otherwise
+	-- writing mem.test = mem in the lua controlled tube will lead to infinite recursion
+	local seen = {}
+
+	local function rfuncs(x)
+		if seen[x] then return end
+		seen[x] = true
+		if type(x) ~= "table" then return end
+
+		for key, value in pairs(x) do
+			if type(key) == "function" or type(value) == "function" then
+				x[key] = nil
+			else
+				if type(key) == "table" then
+					rfuncs(key)
+				end
+				if type(value) == "table" then
+					rfuncs(value)
+				end
+			end
+		end
+	end
+
+	rfuncs(x)
+
+	return x
+end
+
+local function get_interrupt(pos)
+	-- iid = interrupt id
+	local function interrupt(time, iid)
+		if type(time) ~= "number" then return end
+		local luac_id = minetest.get_meta(pos):get_int("luac_id")
+		mesecon.queue:add_action(pos, "pipeworks:lc_tube_interrupt", {luac_id, iid}, time, iid, 1)
+	end
+	return interrupt
+end
+
+
+local function get_digiline_send(pos)
+	if not digiline then return end
+	return function(channel, msg)
+		-- Make sure channel is string, number or boolean
+		if (type(channel) ~= "string" and type(channel) ~= "number" and type(channel) ~= "boolean") then
+			return false
+		end
+
+		-- It is technically possible to send functions over the wire since
+		-- the high performance impact of stripping those from the data has
+		-- been decided to not be worth the added realism.
+		-- Make sure serialized version of the data is not insanely long to
+		-- prevent DoS-like attacks
+		local msg_ser = minetest.serialize(msg)
+		if #msg_ser > mesecon.setting("luacontroller_digiline_maxlen", 50000) then
+			return false
+		end
+
+		minetest.after(0, function()
+			digilines.receptor_send(pos, digiline.rules.default, channel, msg)
+		end)
+		return true
+	end
+end
+
+
+local safe_globals = {
+	"assert", "error", "ipairs", "next", "pairs", "select",
+	"tonumber", "tostring", "type", "unpack", "_VERSION"
+}
+
+local function create_environment(pos, mem, event)
+	-- Gather variables for the environment
+	local vports = minetest.registered_nodes[minetest.get_node(pos).name].virtual_portstates
+	local vports_copy = {}
+	for k, v in pairs(vports) do vports_copy[k] = v end
+	local rports = get_real_port_states(pos)
+
+	-- Create new library tables on each call to prevent one Luacontroller
+	-- from breaking a library and messing up other Luacontrollers.
+	local env = {
+		pin = merge_port_states(vports, rports),
+		port = vports_copy,
+		event = event,
+		mem = mem,
+		heat = mesecon.get_heat(pos),
+		heat_max = mesecon.setting("overheat_max", 20),
+		print = safe_print,
+		interrupt = get_interrupt(pos),
+		digiline_send = get_digiline_send(pos),
+		string = {
+			byte = string.byte,
+			char = string.char,
+			format = string.format,
+			len = string.len,
+			lower = string.lower,
+			upper = string.upper,
+			rep = safe_string_rep,
+			reverse = string.reverse,
+			sub = string.sub,
+			find = safe_string_find,
+		},
+		math = {
+			abs = math.abs,
+			acos = math.acos,
+			asin = math.asin,
+			atan = math.atan,
+			atan2 = math.atan2,
+			ceil = math.ceil,
+			cos = math.cos,
+			cosh = math.cosh,
+			deg = math.deg,
+			exp = math.exp,
+			floor = math.floor,
+			fmod = math.fmod,
+			frexp = math.frexp,
+			huge = math.huge,
+			ldexp = math.ldexp,
+			log = math.log,
+			log10 = math.log10,
+			max = math.max,
+			min = math.min,
+			modf = math.modf,
+			pi = math.pi,
+			pow = math.pow,
+			rad = math.rad,
+			random = math.random,
+			sin = math.sin,
+			sinh = math.sinh,
+			sqrt = math.sqrt,
+			tan = math.tan,
+			tanh = math.tanh,
+		},
+		table = {
+			concat = table.concat,
+			insert = table.insert,
+			maxn = table.maxn,
+			remove = table.remove,
+			sort = table.sort,
+		},
+		os = {
+			clock = os.clock,
+			difftime = os.difftime,
+			time = os.time,
+			datetable = safe_date,
+		},
+	}
+	env._G = env
+
+	for _, name in pairs(safe_globals) do
+		env[name] = _G[name]
+	end
+
+	return env
+end
+
+
+local function timeout()
+	debug.sethook() -- Clear hook
+	error("Code timed out!", 2)
+end
+
+
+local function create_sandbox(code, env)
+	if code:byte(1) == 27 then
+		return nil, "Binary code prohibited."
+	end
+	local f, msg = loadstring(code)
+	if not f then return nil, msg end
+	setfenv(f, env)
+
+	-- Turn off JIT optimization for user code so that count
+	-- events are generated when adding debug hooks
+	if rawget(_G, "jit") then
+		jit.off(f, true)
+	end
+
+	return function(...)
+		-- Use instruction counter to stop execution
+		-- after luacontroller_maxevents
+		local maxevents = mesecon.setting("luacontroller_maxevents", 10000)
+		debug.sethook(timeout, "", maxevents)
+		local ok, ret = pcall(f, ...)
+		debug.sethook()  -- Clear hook
+		if not ok then error(ret, 0) end
+		return ret
+	end
+end
+
+
+local function load_memory(meta)
+	return minetest.deserialize(meta:get_string("lc_memory")) or {}
+end
+
+
+local function save_memory(pos, meta, mem)
+	local memstring = minetest.serialize(remove_functions(mem))
+	local memsize_max = mesecon.setting("luacontroller_memsize", 100000)
+
+	if (#memstring <= memsize_max) then
+		meta:set_string("lc_memory", memstring)
+	else
+		print("Error: lua_tube memory overflow. "..memsize_max.." bytes available, "
+				..#memstring.." required. Controller overheats.")
+		burn_controller(pos)
+	end
+end
+
+
+local function run(pos, event)
+	local meta = minetest.get_meta(pos)
+	if overheat(pos) then return end
+	if ignore_event(event, meta) then return end
+
+	-- Load code & mem from meta
+	local mem  = load_memory(meta)
+	local code = meta:get_string("code")
+
+	-- Create environment
+	local env = create_environment(pos, mem, event)
+
+	-- Create the sandbox and execute code
+	local f, msg = create_sandbox(code, env)
+	if not f then return false, msg end
+	local succ, msg = pcall(f)
+	if not succ then return false, msg end
+	if type(env.port) ~= "table" then
+		return false, "Ports set are invalid."
+	end
+
+	-- Actually set the ports
+	set_port_states(pos, env.port)
+
+	-- Save memory. This may burn the luacontroller if a memory overflow occurs.
+	save_memory(pos, meta, env.mem)
+
+	return succ, msg
+end
+
+mesecon.queue:add_function("pipeworks:lc_tube_interrupt", function (pos, luac_id, iid)
+	-- There is no lua_tube anymore / it has been reprogrammed / replaced / burnt
+	if (minetest.get_meta(pos):get_int("luac_id") ~= luac_id) then return end
+	if (minetest.registered_nodes[minetest.get_node(pos).name].is_burnt) then return end
+	run(pos, {type = "interrupt", iid = iid})
+end)
+
+local function reset_meta(pos, code, errmsg)
+	local meta = minetest.get_meta(pos)
+	meta:set_string("code", code)
+	code = minetest.formspec_escape(code or "")
+	errmsg = minetest.formspec_escape(tostring(errmsg or ""))
+	meta:set_string("formspec", "size[12,10]"..
+		"background[-0.2,-0.25;12.4,10.75;jeija_luac_background.png]"..
+		"textarea[0.2,0.2;12.2,9.5;code;;"..code.."]"..
+		"image_button[4.75,8.75;2.5,1;jeija_luac_runbutton.png;program;]"..
+		"image_button_exit[11.72,-0.25;0.425,0.4;jeija_close_window.png;exit;]"..
+		"label[0.1,9;"..errmsg.."]")
+	meta:set_int("luac_id", math.random(1, 65535))
+end
+
+local function reset(pos)
+	set_port_states(pos, {red = false, blue = false, yellow = false,
+		green = false, black = false, white = false})
+end
+
+
+-----------------------
+-- Node Registration --
+-----------------------
+
+local output_rules = {}
+local input_rules = {}
+
+local node_box = {
+	type = "fixed",
+	fixed = {
+		pipeworks.tube_leftstub[1],   -- tube segment against -X face
+		pipeworks.tube_rightstub[1],  -- tube segment against +X face
+		pipeworks.tube_bottomstub[1], -- tube segment against -Y face
+		pipeworks.tube_topstub[1],    -- tube segment against +Y face
+		pipeworks.tube_frontstub[1],  -- tube segment against -Z face
+		pipeworks.tube_backstub[1],   -- tube segment against +Z face
+	}
+}
+
+local selection_box = {
+	type = "fixed",
+	fixed = pipeworks.tube_selectboxes,
+}
+
+local digiline = {
+	receptor = {},
+	effector = {
+		action = function(pos, node, channel, msg)
+			run(pos, {type = "digiline", channel = channel, msg = msg})
+		end
+	}
+}
+local function on_receive_fields(pos, form_name, fields, sender)
+	if not fields.program then
+		return
+	end
+	local name = sender:get_player_name()
+	if minetest.is_protected(pos, name) and not minetest.check_player_privs(name, {protection_bypass=true}) then
+		minetest.record_protection_violation(pos, name)
+		return
+	end
+	reset(pos)
+	reset_meta(pos, fields.code)
+	local succ, err = run(pos, {type="program"})
+	if not succ then
+		print(err)
+		reset_meta(pos, fields.code, err)
+	end
+end
+
+local function go_back(velocity)
+	local adjlist={{x=0,y=0,z=1},{x=0,y=0,z=-1},{x=0,y=1,z=0},{x=0,y=-1,z=0},{x=1,y=0,z=0},{x=-1,y=0,z=0}}
+	local speed = math.abs(velocity.x + velocity.y + velocity.z)
+	if speed == 0 then
+		speed = 1
+	end
+	local vel = {x = velocity.x/speed, y = velocity.y/speed, z = velocity.z/speed,speed=speed}
+	if speed >= 4.1 then
+		speed = 4
+	elseif speed >= 1.1 then
+		speed = speed - 0.1
+	else
+		speed = 1
+	end
+	vel.speed = speed
+	return pipeworks.notvel(adjlist, vel)
+end
+
+local tiles_base = {
+	"pipeworks_mese_tube_plain_4.png", "pipeworks_mese_tube_plain_3.png",
+	"pipeworks_mese_tube_plain_2.png", "pipeworks_mese_tube_plain_1.png",
+	"pipeworks_mese_tube_plain_6.png", "pipeworks_mese_tube_plain_5.png"}
+
+for red    = 0, 1 do -- 0 = off  1 = on
+for blue   = 0, 1 do
+for yellow = 0, 1 do
+for green  = 0, 1 do
+for black  = 0, 1 do
+for white  = 0, 1 do
+	local cid = tostring(white)..tostring(black)..tostring(green)..
+			tostring(yellow)..tostring(blue)..tostring(red)
+	local node_name = BASENAME..cid
+	local tiles = table.copy(tiles_base)
+	if red == 1 then
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+	else
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+	end
+	if blue == 1 then
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+	else
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+	end
+	if yellow == 1 then
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+	else
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+		tiles[5] = tiles[5].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+		tiles[6] = tiles[6].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+	end
+	if green == 1 then
+		tiles[3] = tiles[3].."^pipeworks_lua_tube_port_on.png"
+		tiles[4] = tiles[4].."^pipeworks_lua_tube_port_on.png"
+		tiles[5] = tiles[5].."^pipeworks_lua_tube_port_on.png"
+		tiles[6] = tiles[6].."^pipeworks_lua_tube_port_on.png"
+	else
+		tiles[3] = tiles[3].."^pipeworks_lua_tube_port_off.png"
+		tiles[4] = tiles[4].."^pipeworks_lua_tube_port_off.png"
+		tiles[5] = tiles[5].."^pipeworks_lua_tube_port_off.png"
+		tiles[6] = tiles[6].."^pipeworks_lua_tube_port_off.png"
+	end
+	if black == 1 then
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+		tiles[2] = tiles[2].."^pipeworks_lua_tube_port_on.png"
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+	else
+		tiles[1] = tiles[1].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+		tiles[2] = tiles[2].."^pipeworks_lua_tube_port_off.png"
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+	end
+	if white == 1 then
+		tiles[1] = tiles[1].."^pipeworks_lua_tube_port_on.png"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_on.png^[transformR180)"
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_on.png^[transformR270)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_on.png^[transformR90)"
+	else
+		tiles[1] = tiles[1].."^pipeworks_lua_tube_port_off.png"
+		tiles[2] = tiles[2].."^(pipeworks_lua_tube_port_off.png^[transformR180)"
+		tiles[3] = tiles[3].."^(pipeworks_lua_tube_port_off.png^[transformR270)"
+		tiles[4] = tiles[4].."^(pipeworks_lua_tube_port_off.png^[transformR90)"
+	end
+
+	local groups = {snappy = 3, tube = 1, tubedevice = 1, overheat = 1}
+	if red + blue + yellow + green + black + white ~= 0 then
+		groups.not_in_creative_inventory = 1
+	end
+
+	output_rules[cid] = {}
+	input_rules[cid] = {}
+	if red    == 1 then table.insert(output_rules[cid], rules.red)    end
+	if blue   == 1 then table.insert(output_rules[cid], rules.blue)   end
+	if yellow == 1 then table.insert(output_rules[cid], rules.yellow) end
+	if green  == 1 then table.insert(output_rules[cid], rules.green)  end
+	if black  == 1 then table.insert(output_rules[cid], rules.black)  end
+	if white  == 1 then table.insert(output_rules[cid], rules.white)  end
+
+	if red    == 0 then table.insert( input_rules[cid], rules.red)    end
+	if blue   == 0 then table.insert( input_rules[cid], rules.blue)   end
+	if yellow == 0 then table.insert( input_rules[cid], rules.yellow) end
+	if green  == 0 then table.insert( input_rules[cid], rules.green)  end
+	if black  == 0 then table.insert( input_rules[cid], rules.black)  end
+	if white  == 0 then table.insert( input_rules[cid], rules.white)  end
+
+	local mesecons = {
+		effector = {
+			rules = input_rules[cid],
+			action_change = function (pos, _, rule_name, new_state)
+				update_real_port_states(pos, rule_name, new_state)
+				run(pos, {type=new_state, pin=rule_name})
+			end,
+		},
+		receptor = {
+			state = mesecon.state.on,
+			rules = output_rules[cid]
+		}
+	}
+
+	minetest.register_node(node_name, {
+		description = "Lua controlled Tube",
+		drawtype = "nodebox",
+		tiles = tiles,
+		paramtype = "light",
+		groups = groups,
+		drop = BASENAME.."000000",
+		sunlight_propagates = true,
+		selection_box = selection_box,
+		node_box = node_box,
+		on_construct = reset_meta,
+		on_receive_fields = on_receive_fields,
+		sounds = default.node_sound_wood_defaults(),
+		mesecons = mesecons,
+		digiline = digiline,
+		-- Virtual portstates are the ports that
+		-- the node shows as powered up (light up).
+		virtual_portstates = {
+			red    = red    == 1,
+			blue   = blue   == 1,
+			yellow = yellow == 1,
+			green  = green  == 1,
+			black  = black  == 1,
+			white  = white  == 1,
+		},
+		after_dig_node = function(pos, node)
+			mesecon.do_cooldown(pos)
+			mesecon.receptor_off(pos, output_rules)
+			pipeworks.after_dig(pos, node)
+		end,
+		is_luacontroller = true,
+		tubelike = 1,
+		tube = {
+			connect_sides = {front = 1, back = 1, left = 1, right = 1, top = 1, bottom = 1},
+			priority = 50,
+			can_go = function(pos, node, velocity, stack)
+				local succ, msg = run(pos, {
+					type = "item",
+					itemstring = stack:to_string(),
+					item = stack:to_table(),
+					velocity = velocity,
+				})
+				if not succ or type(msg) ~= "string" then
+					return go_back(velocity)
+				end
+				local r = rules[msg]
+				return r and {r} or go_back(velocity)
+			end,
+		},
+		after_place_node = pipeworks.after_place,
+		on_blast = function(pos, intensity)
+			if not intensity or intensity > 1 + 3^0.5 then
+				minetest.remove_node(pos)
+				return {string.format("%s_%s", name, dropname)}
+			end
+			minetest.swap_node(pos, {name = "pipeworks:broken_tube_1"})
+			pipeworks.scan_for_tube_objects(pos)
+		end,
+		on_blast = function(pos, intensity)
+			if not intensity or intensity > 1 + 3^0.5 then
+				minetest.remove_node(pos)
+				return {string.format("%s_%s", name, dropname)}
+			end
+			minetest.swap_node(pos, {name = "pipeworks:broken_tube_1"})
+			pipeworks.scan_for_tube_objects(pos)
+		end,
+	})
+end
+end
+end
+end
+end
+end
+
+------------------------------------
+-- Overheated Lua controlled Tube --
+------------------------------------
+
+local tiles_burnt = table.copy(tiles_base)
+tiles_burnt[1] = tiles_burnt[1].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+tiles_burnt[2] = tiles_burnt[2].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+tiles_burnt[5] = tiles_burnt[5].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[6] = tiles_burnt[6].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+tiles_burnt[1] = tiles_burnt[1].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[2] = tiles_burnt[2].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[5] = tiles_burnt[5].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+tiles_burnt[6] = tiles_burnt[6].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[3] = tiles_burnt[3].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[4] = tiles_burnt[4].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[5] = tiles_burnt[5].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[6] = tiles_burnt[6].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[3] = tiles_burnt[3].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[4] = tiles_burnt[4].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[5] = tiles_burnt[5].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[6] = tiles_burnt[6].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[1] = tiles_burnt[1].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[2] = tiles_burnt[2].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[3] = tiles_burnt[3].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+tiles_burnt[4] = tiles_burnt[4].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[1] = tiles_burnt[1].."^pipeworks_lua_tube_port_burnt.png"
+tiles_burnt[2] = tiles_burnt[2].."^(pipeworks_lua_tube_port_burnt.png^[transformR180)"
+tiles_burnt[3] = tiles_burnt[3].."^(pipeworks_lua_tube_port_burnt.png^[transformR270)"
+tiles_burnt[4] = tiles_burnt[4].."^(pipeworks_lua_tube_port_burnt.png^[transformR90)"
+
+minetest.register_node(BASENAME .. "_burnt", {
+	drawtype = "nodebox",
+	tiles = tiles_burnt,
+	is_burnt = true,
+	paramtype = "light",
+	groups = {snappy = 3, tube = 1, tubedevice = 1, not_in_creative_inventory=1},
+	drop = BASENAME.."000000",
+	sunlight_propagates = true,
+	selection_box = selection_box,
+	node_box = node_box,
+	on_construct = reset_meta,
+	on_receive_fields = on_receive_fields,
+	sounds = default.node_sound_wood_defaults(),
+	virtual_portstates = {red = false, blue = false, yellow = false,
+		green = false, black = false, white = false},
+	mesecons = {
+		effector = {
+			rules = mesecon.rules.alldirs,
+			action_change = function(pos, _, rule_name, new_state)
+				update_real_port_states(pos, rule_name, new_state)
+			end,
+		},
+	},
+	tubelike = 1,
+	tube = {
+		connect_sides = {front = 1, back = 1, left = 1, right = 1, top = 1, bottom = 1},
+		priority = 50,
+	},
+	after_place_node = pipeworks.after_place,
+	after_dig_node = pipeworks.after_dig,
+	on_blast = function(pos, intensity)
+		if not intensity or intensity > 1 + 3^0.5 then
+			minetest.remove_node(pos)
+			return {string.format("%s_%s", name, dropname)}
+		end
+		minetest.swap_node(pos, {name = "pipeworks:broken_tube_1"})
+		pipeworks.scan_for_tube_objects(pos)
+	end,
+})
+
+------------------------
+-- Craft Registration --
+------------------------
+
+minetest.register_craft({
+	type = "shapeless",
+	output = BASENAME.."000000",
+	recipe = {"pipeworks:mese_tube_000000", "mesecons_luacontroller:luacontroller0000"},
+})
diff --git a/models.lua b/models.lua
index 3be773c..d9928d2 100644
--- a/models.lua
+++ b/models.lua
@@ -33,8 +33,8 @@ pipeworks.tube_frontstub = {
 }
 
 pipeworks.tube_backstub = {
-	{ -9/64, -9/64, -9/64,   9/64, 9/64, 32/64 },	-- tube segment against -Z face
-} 
+	{ -9/64, -9/64, -9/64,   9/64, 9/64, 32/64 },	-- tube segment against +Z face
+}
 
 pipeworks.tube_boxes = {pipeworks.tube_leftstub, pipeworks.tube_rightstub, pipeworks.tube_bottomstub, pipeworks.tube_topstub, pipeworks.tube_frontstub, pipeworks.tube_backstub}
 
diff --git a/settingtypes.txt b/settingtypes.txt
index 5086bcf..cd6efbc 100644
--- a/settingtypes.txt
+++ b/settingtypes.txt
@@ -63,6 +63,10 @@ pipeworks_enable_one_way_tube (Enable One Way Tube) bool true
 #always go to it if there are multible ways.
 pipeworks_enable_priority_tube (Enable High Priority Tube) bool true
 
+#Enable lua controlled tube.
+#It is comparable with mesecons luacontroller.
+pipeworks_enable_lua_tube (Enable Lua controlled Tube) bool true
+
 #Enable cyclic mode.
 pipeworks_enable_cyclic_mode (Enable Cyclic Mode) bool true
 
diff --git a/textures/pipeworks_lua_tube_port_burnt.png b/textures/pipeworks_lua_tube_port_burnt.png
new file mode 100644
index 0000000..3384eff
--- /dev/null
+++ b/textures/pipeworks_lua_tube_port_burnt.png
diff --git a/textures/pipeworks_lua_tube_port_off.png b/textures/pipeworks_lua_tube_port_off.png
new file mode 100644
index 0000000..03f7069
--- /dev/null
+++ b/textures/pipeworks_lua_tube_port_off.png
diff --git a/textures/pipeworks_lua_tube_port_on.png b/textures/pipeworks_lua_tube_port_on.png
new file mode 100644
index 0000000..a7e3d09
--- /dev/null
+++ b/textures/pipeworks_lua_tube_port_on.png