Merge branch 'master' of https://github.com/orwell96/advtrains

39 files changed, 1578 insertions, 290 deletions

diff --git a/advtrains/advtrains/api_doc.txt b/advtrains/advtrains/api_doc.txt
index af9c071..09b3cc1 100644
--- a/advtrains/advtrains/api_doc.txt
+++ b/advtrains/advtrains/api_doc.txt
@@ -134,7 +134,7 @@ minetest.register_node(nodename, {
 	^- the height value of this rail that is saved in the path. usually the median of rely1 and rely2.
 
 	can_dig=function(pos)

-		return not advtrains.is_train_at_pos(pos)

+		return not advtrains.get_train_at_pos(pos)

 	end,

 	after_dig_node=function(pos)

 		advtrains.invalidate_all_paths()

diff --git a/advtrains/advtrains/atc.lua b/advtrains/advtrains/atc.lua
index dcddc65..bf94ba5 100644
--- a/advtrains/advtrains/atc.lua
+++ b/advtrains/advtrains/atc.lua
@@ -5,19 +5,20 @@ local atc={}
 -- ATC persistence table. advtrains.atc is created by init.lua when it loads the save file.
 atc.controllers = {}
 function atc.load_data(data)
-	atc.controllers = data and data.controllers or {}
+	local temp = data and data.controllers or {}
+	--transcode atc controller data to node hashes: table access times for numbers are far less than for strings
+	for pts, data in pairs(temp) do
+		if type(pts)=="number" then
+			pts=minetest.pos_to_string(minetest.get_position_from_hash(pts))
+		end
+		atc.controllers[pts] = data
+	end
 end
 function atc.save_data()
 	return {controllers = atc.controllers}
 end
 --contents: {command="...", arrowconn=0-15 where arrow points}
 
---call from advtrains.detector subprogram
-
-function atc.trigger_controller_train_enter(pos, train_id)
-	atc.send_command(pos)
-end
-
 --general
 
 function atc.send_command(pos)
@@ -40,10 +41,22 @@ function atc.send_command(pos)
 								)
 						advtrains.trains[train_id].atc_command=atc.controllers[pts].command
 						atprint("Sending ATC Command: "..atc.controllers[pts].command)
+						return true
 					end
 				end
+				atwarn("ATC rail at", pos, ": Rail not on train's path! Can't determine arrow direction. Assuming +!")
+				advtrains.trains[train_id].atc_arrow=true
+				advtrains.trains[train_id].atc_command=atc.controllers[pts].command
+				atprint("Sending ATC Command: "..atc.controllers[pts].command)
+			else
+				atwarn("ATC rail at", pos, ": Sending command failed: The train",train_id,"does not exist. This seems to be a bug.")
 			end
+		else
+			atwarn("ATC rail at", pos, ": Sending command failed: There's no train at this position. This seems to be a bug.")
 		end
+	else
+		atwarn("ATC rail at", pos, ": Sending command failed: Entry for controller not found.")
+		atwarn("ATC rail at", pos, ": Please visit controller and click 'Save'")
 	end
 	return false
 end
@@ -121,6 +134,11 @@ advtrains.register_tracks("default", {
 					atc.send_command(pos)
 				end
 			end,
+			advtrains = {
+				on_train_enter = function(pos, train_id)
+					atc.send_command(pos)
+				end,
+			},
 		}
 	end
 }, advtrains.trackpresets.t_30deg_straightonly)
@@ -176,7 +194,7 @@ local matchptn={
 			train.movedir=train.movedir*-1
 			train.atc_arrow = not train.atc_arrow
 		else
-			minetest.chat_send_all(attrans("ATC Reverse command warning: didn't reverse train, train moving!"))
+			atwarn(sid(id), attrans("ATC Reverse command warning: didn't reverse train, train moving!"))
 		end
 		return 1
 	end,
@@ -235,7 +253,7 @@ function atc.execute_atc_command(id, train)
 		local nest, pos, elsepos=0, 1
 		while nest>=0 do
 			if pos>#rest then
-				minetest.chat_send_all(attrans("ATC command syntax error: I statement not closed: @1",command))
+				atwarn(sid(id), attrans("ATC command syntax error: I statement not closed: @1",command))
 				atc.train_reset_command(id)
 				return
 			end
@@ -278,7 +296,7 @@ function atc.execute_atc_command(id, train)
 			end
 		end
 	end
-	minetest.chat_send_all(attrans("ATC command parse error: Unknown command: @1", command))
+	atwarn(sid(id), attrans("ATC command parse error: Unknown command: @1", command))
 	atc.train_reset_command(id)
 end
 
diff --git a/advtrains/advtrains/craft_items.lua b/advtrains/advtrains/craft_items.lua
new file mode 100644
index 0000000..a4db385
--- /dev/null
+++ b/advtrains/advtrains/craft_items.lua
@@ -0,0 +1,23 @@
+ 
+core.register_craftitem("advtrains:boiler", {
+	description = "Boiler",
+	inventory_image = "advtrains_boiler.png",
+})
+
+ 
+core.register_craftitem("advtrains:driver_cab", {
+	description = "driver's cab",
+	inventory_image = "advtrains_driver_cab.png",
+})
+
+ 
+core.register_craftitem("advtrains:wheel", {
+	description = "Wheel",
+	inventory_image = "advtrains_wheel.png",
+})
+
+
+core.register_craftitem("advtrains:chimney", {
+	description = "Chimney",
+	inventory_image = "advtrains_chimney.png",
+})
diff --git a/advtrains/advtrains/crafting.lua b/advtrains/advtrains/crafting.lua
index 5ba12ce..72cd6da 100644
--- a/advtrains/advtrains/crafting.lua
+++ b/advtrains/advtrains/crafting.lua
@@ -65,6 +65,45 @@ minetest.register_craft({
 	},
 })
 
+--boiler
+minetest.register_craft({
+	output = 'advtrains:boiler',
+	recipe = {
+		{'default:steel_ingot', 'default:steel_ingot', 'default:steel_ingot'},
+		{'doors:trapdoor_steel', '', 'default:steel_ingot'},
+		{'default:steel_ingot', 'default:steel_ingot', 'default:steel_ingot'},
+	},
+})
+
+--drivers'cab
+minetest.register_craft({
+	output = 'advtrains:driver_cab',
+	recipe = {
+		{'default:steel_ingot', 'default:steel_ingot', 'default:steel_ingot'},
+		{'', '', 'default:glass'},
+		{'default:steel_ingot', 'default:steel_ingot', 'default:steel_ingot'},
+	},
+})
+
+--drivers'cab
+minetest.register_craft({
+	output = 'advtrains:wheel',
+	recipe = {
+		{'', 'default:steel_ingot', ''},
+		{'default:steel_ingot', 'group:stick', 'default:steel_ingot'},
+		{'', 'default:steel_ingot', ''},
+	},
+})
+
+--chimney
+minetest.register_craft({
+	output = 'advtrains:chimney',
+	recipe = {
+		{'', 'default:steel_ingot', ''},
+		{'', 'default:steel_ingot', 'default:torch'},
+		{'', 'default:steel_ingot', ''},
+	},
+})
 
 
 --misc_nodes
diff --git a/advtrains/advtrains/init.lua b/advtrains/advtrains/init.lua
index b001f1f..c60b2f1 100644
--- a/advtrains/advtrains/init.lua
+++ b/advtrains/advtrains/init.lua
@@ -11,7 +11,7 @@ advtrains = {trains={}, wagon_save={}}
 
 advtrains.modpath = minetest.get_modpath("advtrains")
 
-local function print_concat_table(a)
+function advtrains.print_concat_table(a)
 	local str=""
 	local stra=""
 	for i=1,50 do
@@ -43,7 +43,16 @@ local function print_concat_table(a)
 end
 atprint=function() end
 if minetest.setting_getbool("advtrains_debug") then
-	atprint=function(t, ...) minetest.log("action", "[advtrains]"..print_concat_table({t, ...})) minetest.chat_send_all("[advtrains]"..print_concat_table({t, ...})) end
+	atprint=function(t, ...)
+		local text=advtrains.print_concat_table({t, ...})
+		minetest.log("action", "[advtrains]"..text)
+		minetest.chat_send_all("[advtrains]"..text)
+	end
+end
+atwarn=function(t, ...)
+	local text=advtrains.print_concat_table({t, ...})
+	minetest.log("warning", "[advtrains]"..text)
+	minetest.chat_send_all("[advtrains] -!- "..text)
 end
 sid=function(id) return string.sub(id, -4) end
 
@@ -80,6 +89,8 @@ dofile(advtrains.modpath.."/damage.lua")
 dofile(advtrains.modpath.."/signals.lua")
 dofile(advtrains.modpath.."/misc_nodes.lua")
 dofile(advtrains.modpath.."/crafting.lua")
+dofile(advtrains.modpath.."/craft_items.lua")
+
 
 --load/save
 
@@ -96,7 +107,6 @@ else
 			advtrains.wagon_save = tbl.wagon_save
 			advtrains.ndb.load_data(tbl.ndb)
 			advtrains.atc.load_data(tbl.atc)
-			--advtrains.latc.load_data(tbl.latc)
 		else
 			--oh no, its the old one...
 			advtrains.trains=tbl
@@ -165,7 +175,6 @@ advtrains.save = function()
 		trains = advtrains.trains,
 		wagon_save = advtrains.wagon_save,
 		atc = advtrains.atc.save_data(),
-		--latc = advtrains.latc.save_data(),
 		ndb = advtrains.ndb.save_data(),
 		version = 1,
 	}
diff --git a/advtrains/advtrains/lua_atc.lua b/advtrains/advtrains/lua_atc.lua
deleted file mode 100644
index 313d70d..0000000
--- a/advtrains/advtrains/lua_atc.lua
+++ /dev/null
@@ -1,166 +0,0 @@
--------------
---LUA ATC controllers
-
-local latc={}
-
-function latc.load_data(data)
-end
-function latc.save_data()
-	return stuff
-end
-
-latc.data
-latc.env_cdata
-latc.init_code=""
-latc.step_code=""
-
-advtrains.fpath_latc=minetest.get_worldpath().."/advtrains_latc"
-local file, err = io.open(advtrains.fpath_atc, "r")
-if not file then
-	local er=err or "Unknown Error"
-	atprint("Failed loading advtrains latc save file "..er)
-else
-	local tbl = minetest.deserialize(file:read("*a"))
-	if type(tbl) == "table" then
-		atc.controllers=tbl.controllers
-	end
-	file:close()
-end
-function latc.save()
-	
-	local datastr = minetest.serialize({controllers = atc.controllers})
-	if not datastr then
-		minetest.log("error", " Failed to serialize latc data!")
-		return
-	end
-	local file, err = io.open(advtrains.fpath_atc, "w")
-	if err then
-		return err
-	end
-	file:write(datastr)
-	file:close()
-end
-
---Privilege
---Only trusted players should be enabled to build stuff which can break the server.
---If I later decide to have multiple environments ('data' tables), I better store an owner for every controller for future reference.
-
-minetest.register_privilege("advtrains_lua_atc", { description = "Player can place and modify LUA ATC components. Grant with care! Allows to execute bad LUA code.", give_to_singleplayer = false, default= false })
-
---Environment
---Code from mesecons_luacontroller (credit goes to Jeija and mesecons contributors)
-
-local safe_globals = {
-	"assert", "error", "ipairs", "next", "pairs", "select",
-	"tonumber", "tostring", "type", "unpack", "_VERSION"
-}
-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 LuaController")
-	end
-
-	return string.find(...)
-end
-
-latc.static_env = {
-	print = safe_print,
-	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,
-	},
-}
-latc.static_env._G = env
-
-for _, name in pairs(safe_globals) do
-	latc.static_env[name] = _G[name]
-end
-
-
---The environment all code calls get is a proxy table with a metatable.
---When an index is read:
--- Look in static_env
--- Look in volatile_env (user_written functions and userdata)
--- Look in saved_env (everything that's not a function or userdata)
---when an index is written:
--- If in static_env, do not allow
--- if function or userdata, volatile_env
--- if table, see below
--- else, save in saved_env
-
-
-
-advtrains.latc=latc
diff --git a/advtrains/advtrains/models/advtrains_signal_wall_l.b3d b/advtrains/advtrains/models/advtrains_signal_wall_l.b3d
new file mode 100644
index 0000000..b1bcbcf
--- /dev/null
+++ b/advtrains/advtrains/models/advtrains_signal_wall_l.b3d
diff --git a/advtrains/advtrains/models/advtrains_signal_wall_r.b3d b/advtrains/advtrains/models/advtrains_signal_wall_r.b3d
new file mode 100644
index 0000000..cf26389
--- /dev/null
+++ b/advtrains/advtrains/models/advtrains_signal_wall_r.b3d
diff --git a/advtrains/advtrains/nodedb.lua b/advtrains/advtrains/nodedb.lua
index 0e1d836..ddd1a67 100644
--- a/advtrains/advtrains/nodedb.lua
+++ b/advtrains/advtrains/nodedb.lua
@@ -2,42 +2,22 @@
 --database of all nodes that have 'save_in_nodedb' field set to true in node definition
 
 
-
 --serialization format:
---(6byte poshash) (2byte contentid)
+--(2byte z) (2byte y) (2byte x) (2byte contentid)
 --contentid := (14bit nodeid, 2bit param2)
 
-local function hash_to_bytes(x)
-	local aH = math.floor(x / 1099511627776) % 256;
-	local aL = math.floor(x /    4294967296) % 256;
-	local bH = math.floor(x /      16777216) % 256;
-	local bL = math.floor(x /         65536) % 256;
-	local cH = math.floor(x /           256) % 256;
-	local cL = math.floor(x                ) % 256;
-	return(string.char(aH, aL, bH, bL, cH, cL));
-end
-local function cid_to_bytes(x)
+local function int_to_bytes(i)
+	local x=i+32768--clip to positive integers
 	local cH = math.floor(x /           256) % 256;
 	local cL = math.floor(x                ) % 256;
 	return(string.char(cH, cL));
 end
-local function bytes_to_hash(bytes)
-	local t={string.byte(bytes,1,-1)}
-	local n = 
-		t[1] * 1099511627776 +
-		t[2] *    4294967296 +
-		t[3] *      16777216 +
-		t[4] *         65536 +
-		t[5] *           256 +
-		t[6]
-    return n
-end
-local function bytes_to_cid(bytes)
+local function bytes_to_int(bytes)
 	local t={string.byte(bytes,1,-1)}
 	local n = 
 		t[1] *           256 +
 		t[2]
-    return n
+    return n-32768
 end
 local function l2b(x)
 	return x%4
@@ -51,25 +31,50 @@ local ndb={}
 local ndb_nodeids={}
 local ndb_nodes={}
 
+local function ndbget(x,y,z)
+	local ny=ndb_nodes[y]
+	if ny then
+		local nx=ny[x]
+		if nx then
+			return nx[z]
+		end
+	end
+	return nil
+end
+local function ndbset(x,y,z,v)
+	if not ndb_nodes[y] then
+		ndb_nodes[y]={}
+	end
+	if not ndb_nodes[y][x] then
+		ndb_nodes[y][x]={}
+	end
+	ndb_nodes[y][x][z]=v
+end
+
+
 --load
 --nodeids get loaded by advtrains init.lua and passed here
 function ndb.load_data(data)
 	ndb_nodeids = data and data.nodeids or {}
 end
 
-local path=minetest.get_worldpath().."/advtrains_ndb"
+local path=minetest.get_worldpath().."/advtrains_ndb2"
 
 local file, err = io.open(path, "r")
 if not file then
 	atprint("load ndb failed: ", err or "Unknown Error")
 else
 	local cnt=0
-	local hst=file:read(6)
+	local hst_z=file:read(2)
+	local hst_y=file:read(2)
+	local hst_x=file:read(2)
 	local cid=file:read(2)
-	while hst and #hst==6 and cid and #cid==2 do
-		ndb_nodes[bytes_to_hash(hst)]=bytes_to_cid(cid)
+	while hst_z and hst_y and hst_x and cid and #hst_z==2 and #hst_y==2 and #hst_x==2 and #cid==2 do
+		ndbset(bytes_to_int(hst_x), bytes_to_int(hst_y), bytes_to_int(hst_z), bytes_to_int(cid))
 		cnt=cnt+1
-		hst=file:read(6)
+		hst_z=file:read(2)
+		hst_y=file:read(2)
+		hst_x=file:read(2)
 		cid=file:read(2)
 	end
 	atprint("nodedb: read", cnt, "nodes.")
@@ -80,11 +85,17 @@ end
 function ndb.save_data()
 	local file, err = io.open(path, "w")
 	if not file then
-		atprint("load ndb failed: ", err or "Unknown Error")
+		atprint("save ndb failed: ", err or "Unknown Error")
 	else
-		for hash, cid in pairs(ndb_nodes) do
-			file:write(hash_to_bytes(hash))
-			file:write(cid_to_bytes(cid))
+		for y, ny in pairs(ndb_nodes) do
+			for x, nx in pairs(ny) do
+				for z, cid in pairs(nx) do
+					file:write(int_to_bytes(z))
+					file:write(int_to_bytes(y))
+					file:write(int_to_bytes(x))
+					file:write(int_to_bytes(cid))
+				end
+			end
 		end
 		file:close()
 	end
@@ -98,7 +109,7 @@ function ndb.get_node_or_nil(pos)
 		return node
 	else
 		--maybe we have the node in the database...
-		local cid=ndb_nodes[minetest.hash_node_position(pos)]
+		local cid=ndbget(pos.x, pos.y, pos.z)
 		if cid then
 			local nodeid = ndb_nodeids[u14b(cid)]
 			if nodeid then
@@ -136,19 +147,16 @@ function ndb.update(pos, pnode)
 			nid=#ndb_nodeids+1
 			ndb_nodeids[nid]=node.name
 		end
-		local hash = minetest.hash_node_position(pos)
-		ndb_nodes[hash] = (nid * 4) + (l2b(node.param2 or 0))
+		ndbset(pos.x, pos.y, pos.z, (nid * 4) + (l2b(node.param2 or 0)) )
 		--atprint("nodedb: updating node", pos, "stored nid",nid,"assigned",ndb_nodeids[nid],"resulting cid",ndb_nodes[hash])
 	else
 		--at this position there is no longer a node that needs to be tracked.
-		local hash = minetest.hash_node_position(pos)
-		ndb_nodes[hash] = nil
+		ndbset(pos.x, pos.y, pos.z, nil)
 	end
 end
 
 function ndb.clear(pos)
-	local hash = minetest.hash_node_position(pos)
-	ndb_nodes[hash] = nil
+	ndbset(pos.x, pos.y, pos.z, nil)
 end
 
 
@@ -195,7 +203,7 @@ minetest.register_abm({
         nodenames = {"group:save_in_nodedb"},
         run_at_every_load = true,
         action = function(pos, node)
-			local cid=ndb_nodes[minetest.hash_node_position(pos)]
+			local cid=ndbget(pos.x, pos.y, pos.z)
 			if cid then
 				--if in database, detect changes and apply.
 				local nodeid = ndb_nodeids[u14b(cid)]
@@ -208,6 +216,10 @@ minetest.register_abm({
 					if (nodeid~=node.name or param2~=node.param2) then
 						atprint("nodedb: lbm replaced", pos, "with nodeid", nodeid, "param2", param2, "cid is", cid)
 						minetest.swap_node(pos, {name=nodeid, param2 = param2})
+						local ndef=minetest.registered_nodes[nodeid]
+						if ndef and ndef.on_updated_from_nodedb then
+							ndef.on_updated_from_nodedb(pos, node)
+						end
 					end
 				end
 			else
@@ -224,9 +236,13 @@ minetest.register_on_dignode(function(pos, oldnode, digger)
 	ndb.clear(pos)
 end)
 
-function ndb.t()
-	return ndb_nodes[141061759008906]
+function ndb.get_nodes()
+	return ndb_nodes
 end
+function ndb.get_nodeids()
+	return ndb_nodeids
+end
+
 
 advtrains.ndb=ndb
 
diff --git a/advtrains/advtrains/signals.lua b/advtrains/advtrains/signals.lua
index d521c8a..cdf610e 100644
--- a/advtrains/advtrains/signals.lua
+++ b/advtrains/advtrains/signals.lua
@@ -1,6 +1,34 @@
 --advtrains by orwell96
 --signals.lua
-for r,f in pairs({on="off", off="on"}) do
+
+--this code /should/ work but does not.
+local mrules_wallsignal_l, mrules_wallsignal_r
+if mesecon then
+	mrules_wallsignal_l = function(node, isright)
+		local rules = mesecon.rules.buttonlike
+		if node.param2 == 1 then
+			rules=mesecon.rotate_rules_left(rules)
+		elseif node.param2 == 2 then
+			rules=mesecon.rotate_rules_right(mesecon.rotate_rules_right(rules))
+		elseif node.param2 == 3 then
+			rules=mesecon.rotate_rules_right(rules)
+		end
+		return rules
+	end
+	mrules_wallsignal_r = function(node)
+		local rules = mesecon.rules.buttonlike
+		if node.param2 == 3 then
+			rules=mesecon.rotate_rules_left(rules)
+		elseif node.param2 == 0 then
+			rules=mesecon.rotate_rules_right(mesecon.rotate_rules_right(rules))
+		elseif node.param2 == 1 then
+			rules=mesecon.rotate_rules_right(rules)
+		end
+		return rules
+	end
+end
+
+for r,f in pairs({on={as="off", ls="green", als="red"}, off={as="on", ls="red", als="green"}}) do
 
 	advtrains.trackplacer.register_tracktype("advtrains:retrosignal", "")
 	advtrains.trackplacer.register_tracktype("advtrains:signal", "")
@@ -32,12 +60,13 @@ for r,f in pairs({on="off", off="on"}) do
 				save_in_nodedb=1,
 			},
 			mesecons = {effector = {
-				["action_"..f] = function (pos, node)
-					advtrains.ndb.swap_node(pos, {name = "advtrains:retrosignal_"..f..rotation, param2 = node.param2})
+				rules=advtrains.meseconrules,
+				["action_"..f.as] = function (pos, node)
+					advtrains.ndb.swap_node(pos, {name = "advtrains:retrosignal_"..f.as..rotation, param2 = node.param2})
 				end
 			}},
 			on_rightclick=function(pos, node, clicker)
-				advtrains.ndb.swap_node(pos, {name = "advtrains:retrosignal_"..f..rotation, param2 = node.param2})
+				advtrains.ndb.swap_node(pos, {name = "advtrains:retrosignal_"..f.as..rotation, param2 = node.param2})
 			end,
 		})
 		advtrains.trackplacer.add_worked("advtrains:retrosignal", r, rotation, nil)
@@ -65,14 +94,107 @@ for r,f in pairs({on="off", off="on"}) do
 			light_source = 1,
 			sunlight_propagates=true,
 			mesecons = {effector = {
-				["action_"..f] = function (pos, node)
-					advtrains.ndb.swap_node(pos, {name = "advtrains:signal_"..f..rotation, param2 = node.param2})
+				rules=advtrains.meseconrules,
+				["action_"..f.as] = function (pos, node)
+					advtrains.ndb.swap_node(pos, {name = "advtrains:signal_"..f.as..rotation, param2 = node.param2})
 				end
 			}},
+			luaautomation = {
+				getstate = f.ls,
+				setstate = function(pos, node, newstate)
+					if newstate == f.als then
+						advtrains.ndb.swap_node(pos, {name = "advtrains:signal_"..f.as..rotation, param2 = node.param2})
+					end
+				end,
+			},
 			on_rightclick=function(pos, node, clicker)
-				advtrains.ndb.swap_node(pos, {name = "advtrains:signal_"..f..rotation, param2 = node.param2})
+				advtrains.ndb.swap_node(pos, {name = "advtrains:signal_"..f.as..rotation, param2 = node.param2})
 			end,
 		})
 		advtrains.trackplacer.add_worked("advtrains:signal", r, rotation, nil)
 	end
+	
+	local crea=1
+	if r=="off" then crea=0 end
+	
+	--tunnel signals. no rotations.
+	minetest.register_node("advtrains:signal_wall_l_"..r, {
+		drawtype = "mesh",
+		paramtype="light",
+		paramtype2="facedir",
+		walkable = false,
+		selection_box = {
+			type = "fixed",
+			fixed = {-1/2, -1/2, -1/4, 0, 1/2, 1/4},
+		},
+		mesh = "advtrains_signal_wall_l.b3d",
+		tiles = {"advtrains_signal_wall_"..r..".png"},
+		drop="advtrains:signal_wall_l_off",
+		description=attrans("Wallmounted Signal, left"),
+		groups = {
+			choppy=3,
+			not_blocking_trains=1,
+			not_in_creative_inventory=crea,
+			save_in_nodedb=1,
+		},
+		light_source = 1,
+		sunlight_propagates=true,
+		mesecons = {effector = {
+			mrules_wallsignal_l,
+			["action_"..f.as] = function (pos, node)
+				advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_l_"..f.as, param2 = node.param2})
+			end
+		}},
+		luaautomation = {
+			getstate = f.ls,
+			setstate = function(pos, node, newstate)
+				if newstate == f.als then
+					advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_l_"..f.as, param2 = node.param2})
+				end
+			end,
+		},
+		on_rightclick=function(pos, node, clicker)
+			advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_l_"..f.as, param2 = node.param2})
+		end,
+	})
+	minetest.register_node("advtrains:signal_wall_r_"..r, {
+		drawtype = "mesh",
+		paramtype="light",
+		paramtype2="facedir",
+		walkable = false,
+		selection_box = {
+			type = "fixed",
+			fixed = {0, -1/2, -1/4, 1/2, 1/2, 1/4},
+		},
+		mesh = "advtrains_signal_wall_r.b3d",
+		tiles = {"advtrains_signal_wall_"..r..".png"},
+		drop="advtrains:signal_wall_r_off",
+		description=attrans("Wallmounted Signal, right"),
+		groups = {
+			choppy=3,
+			not_blocking_trains=1,
+			not_in_creative_inventory=crea,
+			save_in_nodedb=1,
+		},
+		light_source = 1,
+		sunlight_propagates=true,
+		mesecons = {effector = {
+			rules = mrules_wallsignal_r,
+			["action_"..f.as] = function (pos, node)
+				advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_r_"..f.as, param2 = node.param2})
+			end
+		}},
+		luaautomation = {
+			getstate = f.ls,
+			setstate = function(pos, node, newstate)
+				if newstate == f.als then
+					advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_r_"..f.as, param2 = node.param2})
+				end
+			end,
+		},
+		on_rightclick=function(pos, node, clicker)
+			advtrains.ndb.swap_node(pos, {name = "advtrains:signal_wall_r_"..f.as, param2 = node.param2})
+		end,
+	})
+	
 end
diff --git a/advtrains/advtrains/textures/advtrains_boiler.png b/advtrains/advtrains/textures/advtrains_boiler.png
new file mode 100644
index 0000000..8c7ff0d
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_boiler.png
diff --git a/advtrains/advtrains/textures/advtrains_chimney.png b/advtrains/advtrains/textures/advtrains_chimney.png
new file mode 100644
index 0000000..285a1a6
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_chimney.png
diff --git a/advtrains/advtrains/textures/advtrains_driver_cab.png b/advtrains/advtrains/textures/advtrains_driver_cab.png
new file mode 100644
index 0000000..331bcc9
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_driver_cab.png
diff --git a/advtrains/advtrains/textures/advtrains_signal_wall_off.png b/advtrains/advtrains/textures/advtrains_signal_wall_off.png
new file mode 100644
index 0000000..3e7b1e1
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_signal_wall_off.png
diff --git a/advtrains/advtrains/textures/advtrains_signal_wall_on.png b/advtrains/advtrains/textures/advtrains_signal_wall_on.png
new file mode 100644
index 0000000..b628c7e
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_signal_wall_on.png
diff --git a/advtrains/advtrains/textures/advtrains_wheel.png b/advtrains/advtrains/textures/advtrains_wheel.png
new file mode 100644
index 0000000..fb72879
--- /dev/null
+++ b/advtrains/advtrains/textures/advtrains_wheel.png
diff --git a/advtrains/advtrains/trackplacer.lua b/advtrains/advtrains/trackplacer.lua
index d1045aa..e5e3340 100644
--- a/advtrains/advtrains/trackplacer.lua
+++ b/advtrains/advtrains/trackplacer.lua
@@ -230,7 +230,7 @@ minetest.register_craftitem("advtrains:trackworker",{
 			local node=minetest.get_node(pos)
 
 			--if not advtrains.is_track_and_drives_on(minetest.get_node(pos).name, advtrains.all_tracktypes) then return end
-			if advtrains.is_train_at_pos(pos) then return end
+			if advtrains.get_train_at_pos(pos) then return end
 
 			local nnprefix, suffix, rotation=string.match(node.name, "^(.+)_([^_]+)(_[^_]+)$")
 			--atprint(node.name.."\npattern recognizes:"..nodeprefix.." / "..railtype.." / "..rotation)
@@ -272,7 +272,7 @@ minetest.register_craftitem("advtrains:trackworker",{
 			end
 			
 			--if not advtrains.is_track_and_drives_on(minetest.get_node(pos).name, advtrains.all_tracktypes) then return end
-			if advtrains.is_train_at_pos(pos) then return end
+			if advtrains.get_train_at_pos(pos) then return end
 			local nnprefix, suffix, rotation=string.match(node.name, "^(.+)_([^_]+)(_[^_]+)$")
 	        --atprint(node.name.."\npattern recognizes:"..nodeprefix.." / "..railtype.." / "..rotation)
 		    if not tp.tracks[nnprefix] or not tp.tracks[nnprefix].twcycle[suffix] then
diff --git a/advtrains/advtrains/tracks.lua b/advtrains/advtrains/tracks.lua
index a44acb3..63c4f16 100644
--- a/advtrains/advtrains/tracks.lua
+++ b/advtrains/advtrains/tracks.lua
@@ -77,6 +77,12 @@ ap.t_30deg={
 		swrst="on",

 		swrcr="off",

 	},

+	switchst={

+		swlst="st",

+		swlcr="cr",

+		swrst="st",

+		swrcr="cr",

+	},

 	regtp=true,

 	trackplacer={

 		st=true,

@@ -195,6 +201,12 @@ ap.t_45deg={
 		swrst="on",

 		swrcr="off",

 	},

+	switchst={

+		swlst="st",

+		swlcr="cr",

+		swrst="st",

+		swrcr="cr",

+	},

 	regtp=true,

 	trackplacer={

 		st=true,

@@ -233,16 +245,27 @@ advtrains.trackpresets = ap
 	common={} change something on common rail appearance

 }]]

 function advtrains.register_tracks(tracktype, def, preset)

-	local function make_switchfunc(suffix_target, mesecon_state)

-		local switchfunc=function(pos, node)

-			advtrains.ndb.swap_node(pos, {name=def.nodename_prefix.."_"..suffix_target, param2=node.param2})

+	local function make_switchfunc(suffix_target, mesecon_state, is_state)

+		local switchfunc=function(pos, node, newstate)

+			if newstate~=is_state then

+				advtrains.ndb.swap_node(pos, {name=def.nodename_prefix.."_"..suffix_target, param2=node.param2})

+			end

+			advtrains.invalidate_all_paths()

 		end

-		return switchfunc, {effector = {

-			["action_"..mesecon_state] = switchfunc,

-			rules=advtrains.meseconrules

-		}}

+		local mesec

+		if mesecon_state then -- if mesecons is not wanted, do not.

+			mesec = {effector = {

+				["action_"..mesecon_state] = switchfunc,

+				rules=advtrains.meseconrules

+			}}

+		end

+		return switchfunc, mesec,

+		{ 

+			getstate = is_state,

+			setstate = switchfunc,

+		}

 	end

-	local function make_overdef(suffix, rotation, conns, switchfunc, mesecontbl, in_creative_inv, drop_slope)

+	local function make_overdef(suffix, rotation, conns, switchfunc, mesecontbl, luaautomation, in_creative_inv, drop_slope)

 		local img_suffix=suffix..rotation

 		return {

 			mesh = def.shared_model or (def.models_prefix.."_"..img_suffix..def.models_suffix),

@@ -266,6 +289,7 @@ function advtrains.register_tracks(tracktype, def, preset)
 				not_blocking_trains=1,

 			},

 			mesecons=mesecontbl,

+			luaautomation=luaautomation,

 			drop = increativeinv and def.nodename_prefix.."_"..suffix..rotation or (drop_slope and def.nodename_prefix.."_slopeplacer" or def.nodename_prefix.."_placer"),

 			}

 	end

@@ -294,7 +318,7 @@ function advtrains.register_tracks(tracktype, def, preset)
 		railheight=0,

 		drop=def.nodename_prefix.."_placer",

 		can_dig=function(pos)

-			return not advtrains.is_train_at_pos(pos)

+			return not advtrains.get_train_at_pos(pos)

 		end,

 		after_dig_node=function(pos)

 			advtrains.invalidate_all_paths()

@@ -315,9 +339,9 @@ function advtrains.register_tracks(tracktype, def, preset)
 	for suffix, conns in pairs(preset.variant) do

 		for rotid, rotation in ipairs(preset.rotation) do

 			if not def.formats[suffix] or def.formats[suffix][rotid] then

-				local switchfunc, mesecontbl

+				local switchfunc, mesecontbl, luaautomation

 				if preset.switch[suffix] then

-					switchfunc, mesecontbl=make_switchfunc(preset.switch[suffix]..rotation, preset.switchmc[suffix])

+					switchfunc, mesecontbl, luaautomation=make_switchfunc(preset.switch[suffix]..rotation, preset.switchmc[suffix], preset.switchst[suffix])

 				end

 				local adef={}

 				if def.get_additional_definiton then

@@ -329,7 +353,7 @@ function advtrains.register_tracks(tracktype, def, preset)
 					make_overdef(

 						suffix, rotation,

 						cycle_conns(conns, rotid),

-						switchfunc, mesecontbl, preset.increativeinv[suffix], preset.slopenodes[suffix]

+						switchfunc, mesecontbl, luaautomation, preset.increativeinv[suffix], preset.slopenodes[suffix]

 						),

 					adef

 					)

@@ -410,19 +434,16 @@ end
 function advtrains.detector.call_enter_callback(pos, train_id)

 	--atprint("instructed to call enter calback")

 

-	local node = minetest.get_node(pos) --this spares the check if node is nil, it has a name in any case

+	local node = advtrains.ndb.get_node(pos) --this spares the check if node is nil, it has a name in any case

 	local mregnode=minetest.registered_nodes[node.name]

 	if mregnode and mregnode.advtrains and mregnode.advtrains.on_train_enter then

 		mregnode.advtrains.on_train_enter(pos, train_id)

 	end

-	

-	--atc code wants to be notified too

-	advtrains.atc.trigger_controller_train_enter(pos, train_id)

 end

 function advtrains.detector.call_leave_callback(pos, train_id)

 	--atprint("instructed to call leave calback")

 

-	local node = minetest.get_node(pos) --this spares the check if node is nil, it has a name in any case

+	local node = advtrains.ndb.get_node(pos) --this spares the check if node is nil, it has a name in any case

 	local mregnode=minetest.registered_nodes[node.name]

 	if mregnode and mregnode.advtrains and mregnode.advtrains.on_train_leave then

 		mregnode.advtrains.on_train_leave(pos, train_id)

@@ -594,7 +615,7 @@ if mesecon then
 				},

 				advtrains = {

 					on_train_enter=function(pos, train_id)

-						minetest.swap_node(pos, {name="advtrains:dtrack_detector_on".."_"..suffix..rotation, param2=minetest.get_node(pos).param2})

+						advtrains.ndb.swap_node(pos, {name="advtrains:dtrack_detector_on".."_"..suffix..rotation, param2=minetest.get_node(pos).param2})

 						mesecon.receptor_on(pos, advtrains.meseconrules)

 					end

 				}

@@ -619,7 +640,7 @@ if mesecon then
 				},

 				advtrains = {

 					on_train_leave=function(pos, train_id)

-						minetest.swap_node(pos, {name="advtrains:dtrack_detector_off".."_"..suffix..rotation, param2=minetest.get_node(pos).param2})

+						advtrains.ndb.swap_node(pos, {name="advtrains:dtrack_detector_off".."_"..suffix..rotation, param2=minetest.get_node(pos).param2})

 						mesecon.receptor_off(pos, advtrains.meseconrules)

 					end

 				}

diff --git a/advtrains/advtrains/trainlogic.lua b/advtrains/advtrains/trainlogic.lua
index 7238d92..4b5edf5 100644
--- a/advtrains/advtrains/trainlogic.lua
+++ b/advtrains/advtrains/trainlogic.lua
@@ -40,7 +40,14 @@ advtrains.audit_interval=10
 
 
 advtrains.save_and_audit_timer=advtrains.audit_interval
-minetest.register_globalstep(function(dtime)
+minetest.register_globalstep(function(dtime_mt)
+	--limit dtime: if trains move too far in one step, automation may cause stuck and wrongly braking trains
+	local dtime=dtime_mt
+	if dtime>0.2 then
+		atprint("Limiting dtime to 0.2!")
+		dtime=0.2
+	end
+
 	advtrains.save_and_audit_timer=advtrains.save_and_audit_timer-dtime
 	if advtrains.save_and_audit_timer<=0 then
 		local t=os.clock()
@@ -251,8 +258,8 @@ function advtrains.train_step_a(id, train, dtime)
 	
 	--- 5. extend path as necessary ---
 	
-	local gen_front=math.max(train.index, train.detector_old_index) + 2
-	local gen_back=math.min(train.end_index, train.detector_old_end_index) - 2
+	local gen_front=math.max(train.index, train.detector_old_index) + 10
+	local gen_back=math.min(train.end_index, train.detector_old_end_index) - 10
 	
 	local maxn=train.path_extent_max or 0
 	while maxn < gen_front do--pregenerate
@@ -747,31 +754,11 @@ function advtrains.invert_train(train_id)
 	advtrains.update_trainpart_properties(train_id, true)
 end
 
-function advtrains.is_train_at_pos(pos)
-	--atprint("istrainat: pos "..minetest.pos_to_string(pos))
-	local checked_trains={}
-	local objrefs=minetest.get_objects_inside_radius(pos, 2)
-	for _,v in pairs(objrefs) do
-		local le=v:get_luaentity()
-		if le and le.is_wagon and le.initialized and le.train_id and not checked_trains[le.train_id] then
-			--atprint("istrainat: checking "..le.train_id)
-			checked_trains[le.train_id]=true
-			local path=le:train().path
-			if path then
-				--atprint("has path")
-				for i=math.floor(advtrains.get_train_end_index(le:train())+0.5),math.floor(le:train().index+0.5) do
-					if path[i] then
-						--atprint("has pathitem "..i.." "..minetest.pos_to_string(path[i]))
-						if vector.equals(advtrains.round_vector_floor_y(path[i]), pos) then
-							return true
-						end
-					end
-				end
-			end
-		end
-	end
-	return false
+function advtrains.get_train_at_pos(pos)
+	local ph=minetest.pos_to_string(advtrains.round_vector_floor_y(pos))
+	return advtrains.detector.on_node[ph]
 end
+
 function advtrains.invalidate_all_paths()
 	--atprint("invalidating all paths")
 	for k,v in pairs(advtrains.trains) do
diff --git a/advtrains/advtrains/wagons.lua b/advtrains/advtrains/wagons.lua
index 163dc73..0109b19 100644
--- a/advtrains/advtrains/wagons.lua
+++ b/advtrains/advtrains/wagons.lua
@@ -667,7 +667,7 @@ minetest.register_on_player_receive_fields(function(player, formname, fields)
 				if pname~=wagon.owner then

 					return true

 				end

-				if not fields.quit then

+				if fields.save or not fields.quit then

 					for sgr,sgrdef in pairs(wagon.seat_groups) do

 						if fields["sgr_"..sgr] then

 							local fcont = fields["sgr_"..sgr]

diff --git a/advtrains/advtrains_itrainmap/depends.txt b/advtrains/advtrains_itrainmap/depends.txt
new file mode 100644
index 0000000..6f00bf6
--- /dev/null
+++ b/advtrains/advtrains_itrainmap/depends.txt
@@ -0,0 +1 @@
+advtrains
\ No newline at end of file
diff --git a/advtrains/advtrains_itrainmap/init.lua b/advtrains/advtrains_itrainmap/init.lua
new file mode 100644
index 0000000..02dbc9e
--- /dev/null
+++ b/advtrains/advtrains_itrainmap/init.lua
@@ -0,0 +1,144 @@
+
+
+local map_def={
+	example = {
+		p1x=168,
+		p1z=530,
+		p2x=780,
+		p2z=1016,
+		background="itm_example.png",
+	},
+}
+
+local itm_cache={}
+local itm_pdata={}
+local itm_conf_mindia=0.1
+
+minetest.register_privilege("itm", { description = "Allows to display train map", give_to_singleplayer = true, default = false })
+
+local function create_map_form_with_bg(d)
+	local minx, minz, maxx, maxz = math.min(d.p1x, d.p2x), math.min(d.p1z, d.p2z), math.max(d.p1x, d.p2x), math.max(d.p1z, d.p2z)
+	local form_x, form_z=10,10
+	local edge_x, edge_z = form_x/(maxx-minx), form_z/(maxz-minz)
+	local len_x, len_z=math.max(edge_x, itm_conf_mindia), math.max(edge_z, itm_conf_mindia)
+	local form="size["..(form_x+edge_x)..","..(form_z+edge_z).."] background[0,0;0,0;"..d.background..";true] "
+	local lbl={}
+	
+	for pts, tid in pairs(advtrains.detector.on_node) do
+		local pos=minetest.string_to_pos(pts)
+		form=form.."box["..(edge_x*(pos.x-minx))..","..(form_z-(edge_z*(pos.z-minz)))..";"..len_x..","..len_z..";red]"
+		lbl[sid(tid)]=pos
+	end
+	
+	for t_id, xz in pairs(lbl) do
+		form=form.."label["..(edge_x*(xz.x-minx))..","..(form_x-(edge_z*(xz.z-minz)))..";"..t_id.."]"
+	end
+	return form
+end
+
+local function create_map_form(d)
+	if d.background then
+		return create_map_form_with_bg(d)
+	end
+	
+	local minx, minz, maxx, maxz = math.min(d.p1x, d.p2x), math.min(d.p1z, d.p2z), math.max(d.p1x, d.p2x), math.max(d.p1z, d.p2z)
+	local form_x, form_z=10,10
+	local edge_x, edge_z = form_x/(maxx-minx), form_z/(maxz-minz)
+	local len_x, len_z=math.max(edge_x, itm_conf_mindia), math.max(edge_z, itm_conf_mindia)
+	local form="size["..(form_x+edge_x)..","..(form_z+edge_z).."]"
+	local lbl={}
+	
+	for x,itx in pairs(itm_cache) do
+		if x>=minx and x<=maxx then
+			for z,y in pairs(itx) do
+				if z>=minz and z<=maxz then
+					local adn=advtrains.detector.on_node[minetest.pos_to_string({x=x, y=y, z=z})]
+					local color="gray"
+					if adn then
+						color="red"
+						lbl[sid(adn)]={x=x, z=z}
+					end
+					form=form.."box["..(edge_x*(x-minx))..","..(form_z-(edge_z*(z-minz)))..";"..len_x..","..len_z..";"..color.."]"
+				end
+			end
+		end
+	end
+	for t_id, xz in pairs(lbl) do
+		form=form.."label["..(edge_x*(xz.x-minx))..","..(form_x-(edge_z*(xz.z-minz)))..";"..t_id.."]"
+	end
+	return form
+end
+
+local function cache_ndb()
+	itm_cache={}
+	local ndb_nodes=advtrains.ndb.get_nodes()
+	for phs,_ in pairs(ndb_nodes) do
+		local pos=minetest.get_position_from_hash(phs)
+		if not itm_cache[pos.x] then
+			itm_cache[pos.x]={}
+		end
+		itm_cache[pos.x][pos.z]=pos.y
+	end
+end
+
+minetest.register_chatcommand("itm", {
+	params="[x1 z1 x2 z2] or [mdef]",
+	description="Display advtrains train map of given area.\nFirst form:[x1 z1 x2 z2] - specify area directly.\nSecond form:[mdef] - Use a predefined map background(see init.lua)\nThird form: No parameters - use WorldEdit position markers.",
+	privs={itm=true},
+	func = function(name, param)
+		local mdef=string.match(param, "^(%S+)$")
+		if mdef then
+			local d=map_def[mdef]
+			if not d then
+				return false, "Map definiton not found: "..mdef
+			end
+			itm_pdata[name]=map_def[mdef]
+			minetest.show_formspec(name, "itrainmap", create_map_form(d))
+			return true, "Showing train map: "..mdef
+		end
+		local x1, z1, x2, z2=string.match(param, "^(%S+) (%S+) (%S+) (%S+)$")
+		if not (x1 and z1 and x2 and z2) then
+			if worldedit then
+				local wep1, wep2=worldedit.pos1[name], worldedit.pos2[name]
+				if wep1 and wep2 then
+					x1, z1, x2, z2=wep1.x, wep1.z, wep2.x, wep2.z
+				end
+			end
+		end
+		if not (x1 and z1 and x2 and z2) then
+			return false, "Invalid parameters and no WE positions set"
+		end
+		local d={p1x=x1, p1z=z1, p2x=x2, p2z=z2}
+		itm_pdata[name]=d
+		minetest.show_formspec(name, "itrainmap", create_map_form(d))
+		return true, "Showing ("..x1..","..z1..")-("..x2..","..z2..")"
+	end,
+})
+minetest.register_chatcommand("itm_cache_ndb", {
+	params="",
+	description="Cache advtrains node database again. Run when tracks changed.",
+	privs={itm=true},
+	func = function(name, param)
+		cache_ndb()
+		return true, "Done caching node database."
+	end,
+})
+
+local timer=0
+minetest.register_globalstep(function(dtime)
+	timer=timer-math.min(dtime, 0.1)
+	if timer<=0 then
+		for pname,d in pairs(itm_pdata) do
+			minetest.show_formspec(pname, "itrainmap", create_map_form(d))
+		end
+		timer=2
+	end
+end)
+minetest.register_on_player_receive_fields(function(player, formname, fields)
+	if formname=="itrainmap" and fields.quit then
+		itm_pdata[player:get_player_name()]=nil
+	end
+end)
+
+--automatically run itm_cache_ndb
+minetest.after(2, cache_ndb)
diff --git a/advtrains/advtrains_itrainmap/textures/itm_example.png b/advtrains/advtrains_itrainmap/textures/itm_example.png
new file mode 100644
index 0000000..caf084a
--- /dev/null
+++ b/advtrains/advtrains_itrainmap/textures/itm_example.png
diff --git a/advtrains/advtrains_luaautomation/README.txt b/advtrains/advtrains_luaautomation/README.txt
new file mode 100644
index 0000000..6a2114b
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/README.txt
@@ -0,0 +1,155 @@
+
+#### Advtrains - Lua Automation features
+
+This mod offers components that run LUA code and interface with each other through a global environment. It makes complex automated railway systems possible.
+
+### atlatc
+The mod is sometimes abbreviated as 'atlatc'. This stands for AdvTrainsLuaATC. This short name has been chosen for user convenience, since the name of this mod ('advtrains_luaautomation') is very long.
+
+### Privilege
+To perform any operations using this mod (except executing operation panels), players need the "atlatc" privilege.
+This privilege should never be granted to anyone except trusted administrators. Even though the LUA environment is sandboxed, it is still possible to DoS the server by coding infinite loops or requesting expotentially growing interrupts. 
+
+### Active and passive
+Active components are these who have LUA code running in them. They are triggered on specific events. Passive components are dumb, they only have a state and can be set to another state, they can't perform actions themselves.
+
+### Environments
+
+Each active component is assigned to an environment. This is where all data are held. Components in different environments can't inferface with each other.
+This system allows multiple independent automation systems to run simultaneously without polluting each other's environment.
+
+/env_create <env_name>
+Create environment with the given name. To be able to do anything, you first need to create an environment. Choose the name wisely, you can't change it afterwards.
+
+/env_setup <env_name>
+Invoke the form to edit the environment's initialization code. For more information, see the section on active components. You can also delete an environment from here.
+
+### Active components
+
+The code of every active component is run on specific events which are explained soon. When run, every variable written that is not local and is no function or userdata is saved over code re-runs and over server restarts. Additionally, the following global variables are defined:
+
+# event
+The variable 'event' contains a table with information on the current event. How this table can look is explained below.
+
+# S
+The variable 'S' contains a table which is shared between all components of the environment. Its contents are persistent over server restarts. May not contain functions, every other value is allowed.
+Example:
+Component 1: S.stuff="foo"
+Component 2: print(S.stuff)
+-> foo
+
+# F
+The variable 'F' also contains a table which is shared between all components of the environment. Its contents are discarded on server shutdown or when the init code gets re-run. Every data type is allowed, even functions.
+The purpose of this table is not to save data, but to provide static value and function definitions. The table should be populated by the init code.
+
+# Standard Lua functions
+The following standard Lua libraries are available:
+string, math, table, os
+The following standard Lua functions are available:
+assert, error, ipairs, pairs, next, select, tonumber, tostring, type, unpack
+
+Every attempt to overwrite any of the predefined values results in an error.
+
+# LuaAutomation-specific global functions
+
+POS(x,y,z)
+Shorthand function to create a position vector {x=?, y=?, z=?} with less characters
+
+getstate(pos)
+Get the state of the passive component at position 'pos'. See section on passive components for more info.
+
+setstate(pos, newstate)
+Set the state of the passive component at position 'pos'.
+
+interrupt(time, message)
+Cause LuaAutomation to trigger an 'int' event on this component after the given time in seconds with the specified 'message' field. 'message' can be of any Lua data type.
+Not available in init code!
+
+interrupt_pos(pos, message)
+Immediately trigger an 'ext_int' event on the active component at position pos. 'message' is like in interrupt().
+USE WITH CARE, or better don't use! Incorrect use can result in expotential growth of interrupts.
+
+## Components and events
+
+The event table is a table of the following format:
+{
+	type = "<type>",
+	<type> = true,
+	... additional content ...
+}
+You can check for the event type by either using
+if event.type == "wanted" then ...do stuff... end
+or
+if event.wanted then ...do stuff... end
+(if 'wanted' is the event type to check for)
+
+# Init code
+The initialization code is not a component as such, but rather a part of the whole environment. It can (and should) be used to make definitions that other components can refer to.
+Examples:
+A table with the positions of signals mapped to memorizable names, like this:
+F.signals={
+	station_platform1_leave_north=POS(204,5,678),
+	station_platform1_leave_south=POS(202,5,643),
+	station_platform2_leave_north=POS(208,5,678),
+	station_platform2_leave_south=POS(210,5,643),
+}
+A function to define behavior for trains in subway stations:
+function F.station()
+	if event.train then atc_send("B0WOL") end
+	if event.int and event.message="depart" then atc_send("OCD1SM") end
+end
+The init code is run whenever the F table needs to be refilled with data. This is the case on server startup and whenever the init code is changed and you choose to run it.
+Functions are run in the environment of the currently active node, regardless of where they were defined. So, the 'event' table always reflects the state of the calling node.
+
+The 'event' table of the init code is always {type="init", init=true}.
+
+# ATC rails
+The Lua-controlled ATC rails are the only components that can actually interface with trains. The following event types are generated:
+
+{type="train", train=true, id="<train_id>"}
+This event is fired when a train enters the rail. The field 'id' is the unique train ID, which is a long string (generated by concatenating os.time() and os.clock() at creation time). The Itrainmap mod displays the last 4 digits of this ID.
+
+{type="int", int=true, message=<message>}
+Fired when an interrupt set by the 'interrupt' function runs out. 'message' is the message passed to the interrupt function.
+{type="ext_int", ext_int=true, message=<message>}
+Fired when another node called 'interrupt_pos' on this position. 'message' is the message passed to the interrupt_pos function.
+
+In addition to the default environment functions, the following functions are available:
+
+atc_send(<atc_command>)
+	Sends the specified ATC command to the train and returns true. If there is no train, returns false and does nothing.
+atc_reset()
+	Resets the train's current ATC command. If there is no train, returns false and does nothing.
+atc_arrow
+	Boolean, true when the train is driving in the direction of the arrows of the ATC rail. Nil if there is no train.
+atc_id
+	Train ID of the train currently passing the controller. Nil if there's no train.
+atc_speed
+	Speed of the train, or nil if there is no train.
+
+# Operator panel
+This simple node executes its actions when punched. It can be used to change a switch and update the corresponding signals or similar applications.
+
+The event fired is {type="punch", punch=true} by default. In case of an interrupt, the events are similar to the ones of the ATC rail.
+
+### Passive components
+
+All passive components can be interfaced with the setstate and getstate functions(see above).
+Below, each apperance is mapped to the "state" of that node.
+
+## Signals
+The light signals are interfaceable, the analog signals are not.
+"green" - Signal shows green light
+"red" - Signal shows red light
+
+## Switches
+All default rail switches are interfaceable, independent of orientation.
+"cr" - The switch is set in the direction that is not straight.
+"st" - The switch is set in the direction that is straight.
+
+## Mesecon Switch
+The Mesecon switch can be switched using LuaAutomation. Note that this is not possible on levers, only the full-node 'Switch' block.
+"on" - the switch is switched on
+"off" - the switch is switched off
+
+
diff --git a/advtrains/advtrains_luaautomation/active_common.lua b/advtrains/advtrains_luaautomation/active_common.lua
new file mode 100644
index 0000000..0351c85
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/active_common.lua
@@ -0,0 +1,133 @@
+
+
+local ac = {nodes={}}
+
+function ac.load(data)
+	if data then
+		ac.nodes=data.nodes
+	end
+end
+function ac.save()
+	return {nodes = ac.nodes}
+end
+
+function ac.after_place_node(pos, player)
+	advtrains.ndb.update(pos)
+	local meta=minetest.get_meta(pos)
+	meta:set_string("formspec", ac.getform(pos, meta))
+	meta:set_string("infotext", "LuaAutomation component, unconfigured.")
+	local ph=minetest.pos_to_string(pos)
+	--just get first available key!
+	for en,_ in pairs(atlatc.envs) do
+		ac.nodes[ph]={env=en}
+		return
+	end
+end
+function ac.getform(pos, meta_p)
+	local meta = meta_p or minetest.get_meta(pos)
+	local envs_asvalues={}
+	
+	local ph=minetest.pos_to_string(pos)
+	local nodetbl = ac.nodes[ph]
+	local env, code, err = nil, "", ""
+	if nodetbl then
+		code=nodetbl.code or ""
+		err=nodetbl.err or ""
+		env=nodetbl.env or ""
+	end
+	local sel = 1
+	for n,_ in pairs(atlatc.envs) do
+		envs_asvalues[#envs_asvalues+1]=n
+		if n==env then
+			sel=#envs_asvalues
+		end
+	end
+	local form = "size[10,10]dropdown[0,0;3;env;"..table.concat(envs_asvalues, ",")..";"..sel.."]"
+		.."button[4,0;2,1;save;Save]button[7,0;2,1;cle;Clear local env] textarea[0.2,1;10,10;code;Code;"..minetest.formspec_escape(code).."]"
+		.."label[0,9.8;"..err.."]"
+	return form
+end
+
+function ac.after_dig_node(pos, node, player)
+	advtrains.invalidate_all_paths()
+	advtrains.ndb.clear(pos)
+	local ph=minetest.pos_to_string(pos)
+	ac.nodes[ph]=nil
+end
+
+function ac.on_receive_fields(pos, formname, fields, player)
+	if not minetest.check_player_privs(player:get_player_name(), {atlatc=true}) then
+		minetest.chat_send_player(player:get_player_name(), "Missing privilege: atlatc - Operation cancelled!")
+	end
+	
+	local meta=minetest.get_meta(pos)
+	local ph=minetest.pos_to_string(pos)
+	local nodetbl = ac.nodes[ph] or {}
+	--if fields.quit then return end
+	if fields.env then
+		nodetbl.env=fields.env
+	end
+	if fields.code then
+		nodetbl.code=fields.code
+	end
+	if fields.save then
+		nodetbl.err=nil
+	end
+	if fields.cle then
+		nodetbl.data={}
+	end
+	
+	ac.nodes[ph]=nodetbl
+	
+	meta:set_string("formspec", ac.getform(pos, meta))
+	if nodetbl.env then
+		meta:set_string("infotext", "LuaAutomation component, assigned to environment '"..nodetbl.env.."'")
+	else
+		meta:set_string("infotext", "LuaAutomation component, invalid enviroment set!")
+	end
+end
+
+function ac.run_in_env(pos, evtdata, customfct_p)
+	local ph=minetest.pos_to_string(pos)
+	local nodetbl = ac.nodes[ph]
+	if not nodetbl then
+		atwarn("LuaAutomation component at",ph,": Data not in memory! Please visit component and click 'Save'!")
+		return
+	end
+	
+	local meta
+	if minetest.get_node(pos) then
+		meta=minetest.get_meta(pos)
+	end
+	
+	if not nodetbl.env or not atlatc.envs[nodetbl.env] then
+		atwarn("LuaAutomation component at",ph,": Not an existing environment: "..(nodetbl.env or "<nil>"))
+		return false
+	end
+	if not nodetbl.code or nodetbl.code=="" then
+		atwarn("LuaAutomation component at",ph,": No code to run! (insert -- to suppress warning)")
+		return false
+	end
+	
+	local customfct=customfct_p or {}
+	customfct.interrupt=function(t, imesg)
+		atlatc.interrupt.add(t, pos, {type="int", int=true, message=imesg})
+	end
+	
+	local datain=nodetbl.data or {}
+	local succ, dataout = atlatc.envs[nodetbl.env]:execute_code(datain, nodetbl.code, evtdata, customfct)
+	if succ then
+		atlatc.active.nodes[ph].data=atlatc.remove_invalid_data(dataout)
+	else
+		atlatc.active.nodes[ph].err=dataout
+		atwarn("LuaAutomation ATC interface rail at",ph,": LUA Error:",dataout)
+		if meta then
+			meta:set_string("infotext", "LuaAutomation ATC interface rail, ERROR:"..dataout)
+		end
+	end
+	if meta then
+		meta:set_string("formspec", ac.getform(pos, meta))
+	end
+end
+
+atlatc.active=ac
diff --git a/advtrains/advtrains_luaautomation/atc_rail.lua b/advtrains/advtrains_luaautomation/atc_rail.lua
new file mode 100644
index 0000000..c2c8d6f
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/atc_rail.lua
@@ -0,0 +1,106 @@
+-- atc_rail.lua
+-- registers and handles the ATC rail. Active component.
+-- This is the only component that can interface with trains, so train interface goes here too.
+
+--Using subtable
+local r={}
+
+function r.fire_event(pos, evtdata)
+	
+	local ph=minetest.pos_to_string(pos)
+	local railtbl = atlatc.active.nodes[ph]
+	
+	if not railtbl then
+		atwarn("LuaAutomation ATC interface rail at",ph,": Data not in memory! Please visit position and click 'Save'!")
+		return
+	end
+	
+	
+	local arrowconn = railtbl.arrowconn
+	
+	--prepare ingame API for ATC. Regenerate each time since pos needs to be known
+	--If no train, then return false.
+	local train_id=advtrains.detector.on_node[ph]
+	local train, atc_arrow, tvel
+	if train_id then train=advtrains.trains[train_id] end
+	if train then 
+		if not train.path then
+			--we happened to get in between an invalidation step
+			--delay
+			atlatc.interrupt.add(0,pos,evtdata)
+			return
+		end
+		for index, ppos in pairs(train.path) do
+			if vector.equals(advtrains.round_vector_floor_y(ppos), pos) then
+				atc_arrow =
+						vector.equals(
+								advtrains.dirCoordSet(pos, arrowconn),
+								advtrains.round_vector_floor_y(train.path[index+train.movedir])
+						)
+			end
+		end
+		if atc_arrow==nil then
+			atwarn("LuaAutomation ATC rail at", pos, ": Rail not on train's path! Can't determine arrow direction. Assuming +!")
+			atc_arrow=true
+			tvel=train.velocity
+		end
+	end
+	local customfct={
+		atc_send = function(cmd)
+			if not train_id then return false end
+			advtrains.atc.train_reset_command(train_id)
+			train.atc_command=cmd
+			train.atc_arrow=atc_arrow
+			return true
+		end,
+		atc_reset = function(cmd)
+			if not train_id then return false end
+			advtrains.atc.train_reset_command(train_id)
+			return true
+		end,
+		atc_arrow = atc_arrow,
+		atc_id = train_id,
+		atc_speed = tvel,
+	}
+	
+	atlatc.active.run_in_env(pos, evtdata, customfct)
+	
+end
+
+advtrains.register_tracks("default", {
+	nodename_prefix="advtrains_luaautomation:dtrack",
+	texture_prefix="advtrains_dtrack_atc",
+	models_prefix="advtrains_dtrack_detector",
+	models_suffix=".b3d",
+	shared_texture="advtrains_dtrack_rail_atc.png",
+	description=atltrans("LuaAutomation ATC Rail"),
+	formats={},
+	get_additional_definiton = function(def, preset, suffix, rotation)
+		return {
+			after_place_node = atlatc.active.after_place_node,
+			after_dig_node = atlatc.active.after_dig_node,
+
+			on_receive_fields = function(pos, ...)
+				atlatc.active.on_receive_fields(pos, ...)
+				
+				--set arrowconn (for ATC)
+				local ph=minetest.pos_to_string(pos)
+				local _, conn1=advtrains.get_rail_info_at(pos, advtrains.all_tracktypes)
+				atlatc.active.nodes[ph].arrowconn=conn1
+			end,
+
+			advtrains = {
+				on_train_enter = function(pos, train_id)
+					--do async. Event is fired in train steps
+					atlatc.interrupt.add(0, pos, {type="train", train=true, id=train_id})
+				end,
+			},
+			luaautomation = {
+				fire_event=r.fire_event
+			}
+		}
+	end
+}, advtrains.trackpresets.t_30deg_straightonly)
+
+
+atlatc.rail = r
diff --git a/advtrains/advtrains_luaautomation/chatcmds.lua b/advtrains/advtrains_luaautomation/chatcmds.lua
new file mode 100644
index 0000000..2d0c69d
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/chatcmds.lua
@@ -0,0 +1,84 @@
+--chatcmds.lua
+--Registers commands to modify the init and step code for LuaAutomation
+
+--position helper.
+--punching a node will result in that position being saved and inserted into a text field on the top of init form.
+local punchpos={}
+
+minetest.register_on_punchnode(function(pos, node, player, pointed_thing)
+	local pname=player:get_player_name()
+	punchpos[pname]=pos
+end)
+
+local function get_init_form(env, pname)
+	local err = env.init_err or ""
+	local code = env.init_code or ""
+	local ppos=punchpos[pname]
+	local pp=""
+	if ppos then
+		pp="POS"..minetest.pos_to_string(ppos)
+	end
+	local form = "size[10,10]button[0,0;2,1;run;Run InitCode]button[2,0;2,1;cls;Clear S]"
+		.."button[4,0;2,1;save;Save] button[6,0;2,1;del;Delete Env.] field[8.1,0.5;2,1;punchpos;Last punched position;"..pp.."]"
+		.."textarea[0.2,1;10,10;code;Environment initialization code;"..minetest.formspec_escape(code).."]"
+		.."label[0,9.8;"..err.."]"
+	return form
+end
+
+core.register_chatcommand("env_setup", {
+	params = "<environment name>",
+	description = "Set up and modify AdvTrains LuaAutomation environment",
+	privs = {atlatc=true},
+	func = function(name, param)
+		local env=atlatc.envs[param]
+		if not env then return false,"Invalid environment name!" end
+		minetest.show_formspec(name, "atlatc_envsetup_"..param, get_init_form(env, name))
+		return true
+	end,
+})
+
+core.register_chatcommand("env_create", {
+	params = "<environment name>",
+	description = "Create an AdvTrains LuaAutomation environment",
+	privs = {atlatc=true},
+	func = function(name, param)
+		if not param or param=="" then return false, "Name required!" end
+		if atlatc.envs[param] then return false, "Environment already exists!" end
+		atlatc.envs[param] = atlatc.env_new(param)
+		return true, "Created environment '"..param.."'. Use '/env_setup "..param.."' to define global initialization code, or start building LuaATC components!"
+	end,
+})
+
+
+minetest.register_on_player_receive_fields(function(player, formname, fields)
+	
+	local pname=player:get_player_name()
+	if not minetest.check_player_privs(pname, {atlatc=true}) then return end
+	
+	local envname=string.match(formname, "^atlatc_delconfirm_(.+)$")
+	if envname and fields.sure=="YES" then
+		atlatc.envs[envname]=nil
+		minetest.chat_send_player(pname, "Environment deleted!")
+		return
+	end
+	
+	envname=string.match(formname, "^atlatc_envsetup_(.+)$")
+	if not envname then return end
+	
+	local env=atlatc.envs[envname]
+	if not env then return end
+	
+	if fields.del then
+		minetest.show_formspec(pname, "atlatc_delconfirm_"..envname, "field[sure;"..minetest.formspec_escape("SURE TO DELETE ENVIRONMENT "..envname.."? Type YES (all uppercase) to continue or just quit form to cancel.")..";]")
+		return
+	end
+	
+	env.init_err=nil
+	if fields.code then
+		env.init_code=fields.code
+	end
+	if fields.run then
+		env:run_initcode()
+		minetest.show_formspec(pname, formname, get_init_form(env, pname))
+	end
+end)
diff --git a/advtrains/advtrains_luaautomation/depends.txt b/advtrains/advtrains_luaautomation/depends.txt
new file mode 100644
index 0000000..366cad5
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/depends.txt
@@ -0,0 +1,2 @@
+advtrains
+mesecons?
\ No newline at end of file
diff --git a/advtrains/advtrains_luaautomation/environment.lua b/advtrains/advtrains_luaautomation/environment.lua
new file mode 100644
index 0000000..8dfdd39
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/environment.lua
@@ -0,0 +1,288 @@
+-------------
+-- lua sandboxed environment
+
+-- function to cross out functions and userdata.
+-- modified from dump()
+function atlatc.remove_invalid_data(o, nested)
+	if o==nil then return nil end
+	local valid_dt={["nil"]=true, boolean=true, number=true, string=true}
+	if type(o) ~= "table" then
+		--check valid data type
+		if not valid_dt[type(o)] then
+			return nil
+		end
+		return o
+	end
+	-- Contains table -> true/nil of currently nested tables
+	nested = nested or {}
+	if nested[o] then
+		return nil
+	end
+	nested[o] = true
+	for k, v in pairs(o) do
+		v = atlatc.remove_invalid_data(v, nested)
+	end
+	nested[o] = nil
+	return o
+end
+function atlatc.replace_function_envs(o, fenv, nested)
+	if o==nil then return nil end
+	local valid_dt={["nil"]=true, boolean=true, number=true, string=true}
+	if type(o) ~= "table" then
+		--check valid data type
+		if type(o)=="function" then
+			setfenv(o, fenv)
+		end
+		return o
+	end
+	-- Contains table -> true/nil of currently nested tables
+	nested = nested or {}
+	if nested[o] then
+		return nil
+	end
+	nested[o] = true
+	for k, v in pairs(o) do
+		v = atlatc.replace_function_envs(v, fenv, nested)
+	end
+	nested[o] = nil
+	return o
+end
+
+
+local env_proto={
+	load = function(self, envname, data)
+		self.name=envname
+		self.sdata=data.sdata and atlatc.remove_invalid_data(data.sdata) or {}
+		self.fdata={}
+		self.init_code=data.init_code or ""
+		self.step_code=data.step_code or ""
+	end,
+	save = function(self)
+		-- throw any function values out of the sdata table
+		self.sdata = atlatc.remove_invalid_data(self.sdata)
+		return {sdata = self.sdata, init_code=self.init_code, step_code=self.step_code}
+	end,
+}
+
+--Environment
+--Code modified from mesecons_luacontroller (credit goes to Jeija and mesecons contributors)
+
+local safe_globals = {
+	"assert", "error", "ipairs", "next", "pairs", "select",
+	"tonumber", "tostring", "type", "unpack", "_VERSION"
+}
+
+--print is actually minetest.chat_send_all()
+--using advtrains.print_concat_table because it's cool
+local function safe_print(t, ...)
+	local str=advtrains.print_concat_table({t, ...})
+	minetest.log("action", "[atlatc] "..str)
+	minetest.chat_send_all(str)
+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 > 2000 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.
+-- Note: Disabled security since there are enough security leaks and this would be unneccessary anyway to DoS the server
+local function safe_string_find(...)
+	--if (select(4, ...)) ~= true then
+	--	debug.sethook() -- Clear hook
+	--	error("string.find: 'plain' (fourth parameter) must always be true for security reasons.")
+	--end
+
+	return string.find(...)
+end
+
+local mp=minetest.get_modpath("advtrains_luaautomation")
+local p_api_getstate, p_api_setstate = dofile(mp.."/passive.lua")
+
+local static_env = {
+	--core LUA functions
+	print = safe_print,
+	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,
+		date = safe_date,
+	},
+	POS = function(x,y,z) return {x=x, y=y, z=z} end,
+	getstate = p_api_getstate,
+	setstate = p_api_setstate,
+	--interrupts are handled per node, position unknown.
+	--however external interrupts can be set here.
+	interrupt_pos = function(pos, imesg)
+		if not type(pos)=="table" or not pos.x or not pos.y or not pos.z then
+			debug.sethook()
+			error("Invalid position supplied to interrupt_pos")
+		end
+		atlatc.interrupt.add(0, pos, {type="ext_int", ext_int=true, message=imesg})
+	end,
+}
+
+for _, name in pairs(safe_globals) do
+	static_env[name] = _G[name]
+end
+
+
+--The environment all code calls get is a table that has set static_env as metatable.
+--In general, every variable is local to a single code chunk, but kept persistent over code re-runs. Data is also saved, but functions and userdata and circular references are removed
+--Init code and step code's environments are not saved
+-- S - Table that can contain any save data global to the environment. Will be saved statically. Can't contain functions or userdata or circular references.
+-- F - Table global to the environment, can contain volatile data that is deleted when server quits.
+--     The init code should populate this table with functions and other definitions.
+
+-- returns: true, fenv if successful; nil, error if error 
+function env_proto:execute_code(fenv, code, evtdata, customfct)
+	local metatbl ={
+		__index = function(t, i)
+			if i=="S" then
+				return self.sdata
+			elseif i=="F" then
+				return self.fdata
+			elseif i=="event" then
+				return evtdata
+			elseif customfct and customfct[i] then
+				return customfct[i]
+			end
+			return static_env[i]
+		end,
+		__newindex = function(t, i, v)
+			if i=="S" or i=="F" or i=="event" or (customfct and customfct[i]) or static_env[i] then
+				debug.sethook()
+				error("Trying to overwrite environment contents")
+			end
+			rawset(t,i,v)
+		end,
+	}
+	setmetatable(fenv, metatbl)
+	local fun, err=loadstring(code)
+	if not fun then
+		return false, err
+	end
+	--set function environment for all functions residing in F, so they get the right variables. Else it's a huge mess...
+	atlatc.replace_function_envs(self.fdata, fenv)
+	
+	setfenv(fun, fenv)
+	local succ, data = pcall(fun)
+	if succ then
+		data=fenv
+	end
+	return succ, data
+end
+
+function env_proto:run_initcode()
+	if self.init_code and self.init_code~="" then
+		self.fdata = {}
+		atprint("[atlatc]Running initialization code for environment '"..self.name.."'")
+		local succ, err = self:execute_code({}, self.init_code, {type="init", init=true})
+		if not succ then
+			self.init_err=err
+		end
+	end
+end
+function env_proto:run_stepcode()
+	if self.step_code and self.step_code~="" then
+		local succ, err = self:execute_code({}, self.step_code, nil, {})
+		if not succ then
+			--TODO
+		end
+	end
+end
+
+--- class interface
+
+function atlatc.env_new(name)
+	local newenv={
+		name=name,
+		init_code="",
+		step_code="",
+		sdata={}
+	}
+	setmetatable(newenv, {__index=env_proto})
+	return newenv
+end
+function atlatc.env_load(name, data)
+	local newenv={}
+	setmetatable(newenv, {__index=env_proto})
+	newenv:load(name, data)
+	return newenv
+end
+
+function atlatc.run_initcode()
+	for envname, env in pairs(atlatc.envs) do
+		env:run_initcode()
+	end
+end
+function atlatc.run_stepcode()
+	for envname, env in pairs(atlatc.envs) do
+		env:run_stepcode()
+	end
+end
+
+
+
+
diff --git a/advtrains/advtrains_luaautomation/init.lua b/advtrains/advtrains_luaautomation/init.lua
new file mode 100644
index 0000000..feea372
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/init.lua
@@ -0,0 +1,105 @@
+-- advtrains_luaautomation/init.lua
+-- Lua automation features for advtrains
+-- Uses global table 'atlatc' (AdvTrains_LuaATC)
+
+-- Boilerplate to support localized strings if intllib mod is installed.
+if minetest.get_modpath("intllib") then
+    atltrans = intllib.Getter()
+else
+    atltrans = function(s,a,...)a={a,...}return s:gsub("@(%d+)",function(n)return a[tonumber(n)]end)end
+end
+
+--Privilege
+--Only trusted players should be enabled to build stuff which can break the server.
+
+atlatc = { envs = {}}
+
+minetest.register_privilege("atlatc", { description = "Player can place and modify LUA ATC components. Grant with care! Allows to execute bad LUA code.", give_to_singleplayer = false, default= false })
+
+local mp=minetest.get_modpath("advtrains_luaautomation")
+if not mp then
+	error("Mod name error: Mod folder is not named 'advtrains_luaautomation'!")
+end
+dofile(mp.."/environment.lua")
+dofile(mp.."/interrupt.lua")
+dofile(mp.."/active_common.lua")
+dofile(mp.."/atc_rail.lua")
+dofile(mp.."/operation_panel.lua")
+if mesecon then
+	dofile(mp.."/p_mesecon_iface.lua")
+end
+dofile(mp.."/chatcmds.lua")
+
+
+local filename=minetest.get_worldpath().."/advtrains_luaautomation"
+local file, err = io.open(filename, "r")
+if not file then
+	minetest.log("error", " Failed to read advtrains_luaautomation save data from file "..filename..": "..(err or "Unknown Error"))
+else
+	atprint("luaautomation reading file:",filename)
+	local tbl = minetest.deserialize(file:read("*a"))
+	if type(tbl) == "table" then
+		atprint(tbl)
+		if tbl.version==1 then
+			for envname, data in pairs(tbl.envs) do
+				atlatc.envs[envname]=atlatc.env_load(envname, data)
+			end
+			atlatc.active.load(tbl.active)
+			atlatc.interrupt.load(tbl.interrupt)
+		end
+	else
+		minetest.log("error", " Failed to read advtrains_luaautomation save data from file "..filename..": Not a table!")
+	end
+	file:close()
+end
+
+-- run init code of all environments
+atlatc.run_initcode()
+
+atlatc.save = function()
+	--versions:
+	-- 1 - Initial save format.
+	
+	local envdata={}
+	for envname, env in pairs(atlatc.envs) do
+		envdata[envname]=env:save()
+	end
+	local save_tbl={
+		version = 1,
+		envs=envdata,
+		active = atlatc.active.save(),
+		interrupt = atlatc.interrupt.save(),
+	}
+	
+	local datastr = minetest.serialize(save_tbl)
+	if not datastr then
+		minetest.log("error", " Failed to save advtrains_luaautomation save data to file "..filename..": Can't serialize!")
+		return
+	end
+	local file, err = io.open(filename, "w")
+	if err then
+		minetest.log("error", " Failed to save advtrains_luaautomation save data to file "..filename..": "..(err or "Unknown Error"))
+		return
+	end
+	file:write(datastr)
+	file:close()
+end
+
+minetest.register_on_shutdown(atlatc.save)
+
+-- globalstep for step code
+local timer, step_int=0, 2
+local stimer, sstep_int=0, 10
+
+minetest.register_globalstep(function(dtime)
+	timer=timer+dtime
+	if timer>step_int then
+		timer=0
+		atlatc.run_stepcode()
+	end
+	stimer=stimer+dtime
+	if stimer>sstep_int then
+		stimer=0
+		atlatc.save()
+	end
+end)
diff --git a/advtrains/advtrains_luaautomation/interrupt.lua b/advtrains/advtrains_luaautomation/interrupt.lua
new file mode 100644
index 0000000..e9ad443
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/interrupt.lua
@@ -0,0 +1,48 @@
+-- interrupt.lua
+-- implements interrupt queue
+
+--to be saved: pos and evtdata
+local iq={}
+local queue={}
+local timer=0
+local run=false
+
+function iq.load(data)
+	local d=data or {}
+	queue = d.queue or {}
+	timer = d.timer or 0
+end
+function iq.save()
+	return {queue = queue}
+end
+
+function iq.add(t, pos, evtdata)
+	queue[#queue+1]={t=t+timer, p=pos, e=evtdata}
+	run=true
+end
+
+minetest.register_globalstep(function(dtime)
+	if run then
+		timer=timer + math.min(dtime, 0.2)
+		for i=1,#queue do
+			local qe=queue[i]
+			if not qe then
+				table.remove(queue, i)
+				i=i-1
+			elseif timer>qe.t then
+				local pos, evtdata=queue[i].p, queue[i].e
+				local node=advtrains.ndb.get_node(pos)
+				local ndef=minetest.registered_nodes[node.name]
+				if ndef and ndef.luaautomation and ndef.luaautomation.fire_event then
+					ndef.luaautomation.fire_event(pos, evtdata)
+				end
+				table.remove(queue, i)
+				i=i-1
+			end
+		end
+	end
+end)
+
+
+
+atlatc.interrupt=iq
diff --git a/advtrains/advtrains_luaautomation/operation_panel.lua b/advtrains/advtrains_luaautomation/operation_panel.lua
new file mode 100644
index 0000000..1d585f7
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/operation_panel.lua
@@ -0,0 +1,23 @@
+
+local function on_punch(pos, player)
+	atlatc.interrupt.add(0, pos, {type="punch", punch=true})
+end
+
+
+minetest.register_node("advtrains_luaautomation:oppanel", {
+	drawtype = "normal",
+	tiles={"atlatc_oppanel.png"},
+	description = "LuaAutomation operation panel",
+	groups = {
+		choppy = 1,
+		save_in_nodedb=1,
+	},
+	after_place_node = atlatc.active.after_place_node,
+	after_dig_node = atlatc.active.after_dig_node,
+	on_receive_fields = atlatc.active.on_receive_fields,
+	on_punch = on_punch,
+	luaautomation = {
+		fire_event=atlatc.active.run_in_env
+	}
+	
+})
diff --git a/advtrains/advtrains_luaautomation/p_display.lua b/advtrains/advtrains_luaautomation/p_display.lua
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/p_display.lua
diff --git a/advtrains/advtrains_luaautomation/p_mesecon_iface.lua b/advtrains/advtrains_luaautomation/p_mesecon_iface.lua
new file mode 100644
index 0000000..d7e1052
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/p_mesecon_iface.lua
@@ -0,0 +1,60 @@
+-- p_mesecon_iface.lua
+-- Mesecons interface by overriding the switch
+
+if not mesecon then return end
+
+minetest.override_item("mesecons_switch:mesecon_switch_off", {
+	groups = {
+		dig_immediate=2,
+		save_in_nodedb=1,
+	},
+	on_rightclick = function (pos, node)
+		if(mesecon.flipstate(pos, node) == "on") then
+			mesecon.receptor_on(pos)
+		else
+			mesecon.receptor_off(pos)
+		end
+		minetest.sound_play("mesecons_switch", {pos=pos})
+		advtrains.ndb.update(pos, node)
+	end,
+	on_updated_from_nodedb = function(pos, node)
+		mesecon.receptor_off(pos)
+	end,
+	luaautomation = {
+		getstate = "off",
+		setstate = function(pos, node, newstate)
+			if newstate=="on" then
+				advtrains.ndb.swap_node(pos, {name="mesecons_switch:mesecon_switch_on", param2=node.param2})
+				mesecon.receptor_on(pos)
+			end
+		end,
+	},
+})
+
+minetest.override_item("mesecons_switch:mesecon_switch_on", {
+	groups = {
+		dig_immediate=2,
+		save_in_nodedb=1,
+	},
+	on_rightclick = function (pos, node)
+		if(mesecon.flipstate(pos, node) == "on") then
+			mesecon.receptor_on(pos)
+		else
+			mesecon.receptor_off(pos)
+		end
+		minetest.sound_play("mesecons_switch", {pos=pos})
+		advtrains.ndb.update(pos, node)
+	end,
+	on_updated_from_nodedb = function(pos, node)
+		mesecon.receptor_on(pos)
+	end,
+	luaautomation = {
+		getstate = "on",
+		setstate = function(pos, node, newstate)
+			if newstate=="off" then
+				advtrains.ndb.swap_node(pos, {name="mesecons_switch:mesecon_switch_off", param2=node.param2})
+				mesecon.receptor_off(pos)
+			end
+		end,
+	},
+})
diff --git a/advtrains/advtrains_luaautomation/passive.lua b/advtrains/advtrains_luaautomation/passive.lua
new file mode 100644
index 0000000..e32bee9
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/passive.lua
@@ -0,0 +1,37 @@
+-- passive.lua
+-- API to passive components, as described in passive_api.txt
+
+local function getstate(pos)
+	if not type(pos)=="table" or not pos.x or not pos.y or not pos.z then
+		debug.sethook()
+		error("Invalid position supplied to getstate")
+	end
+	local node=advtrains.ndb.get_node(pos)
+	local ndef=minetest.registered_nodes[node.name]
+	if ndef and ndef.luaautomation and ndef.luaautomation.getstate then
+		local st=ndef.luaautomation.getstate
+		if type(st)=="function" then
+			return st(pos, node)
+		else
+			return st
+		end
+	end
+	return nil
+end
+
+local function setstate(pos, newstate)
+	if not type(pos)=="table" or not pos.x or not pos.y or not pos.z then
+		debug.sethook()
+		error("Invalid position supplied to setstate")
+	end
+	local node=advtrains.ndb.get_node(pos)
+	local ndef=minetest.registered_nodes[node.name]
+	if ndef and ndef.luaautomation and ndef.luaautomation.setstate then
+		local st=ndef.luaautomation.setstate
+		st(pos, node, newstate)
+	end
+end
+
+-- gets called from environment.lua
+-- return the values here to keep them local
+return getstate, setstate
diff --git a/advtrains/advtrains_luaautomation/passive_api.txt b/advtrains/advtrains_luaautomation/passive_api.txt
new file mode 100644
index 0000000..a735208
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/passive_api.txt
@@ -0,0 +1,23 @@
+Lua Automation - Passive Component API
+
+Passive components are nodes that do not have code running in them. However, active components can query these and request actions from them. Examples:
+Switches
+Signals
+Displays
+Mesecon Transmitter
+
+All passive components have a table called 'luaautomation' in their node definition and have the group 'save_in_nodedb' set, so they work in unloaded chunks.
+Example for a switch:
+luaautomation = {
+	getstate = function(pos, node)
+		return "st"
+	end,
+	-- OR
+	getstate = "st",
+
+	setstate = function(pos, node, newstate)
+		if newstate=="cr" then
+			advtrains.ndb.swap_node(pos, <corresponding switch alt>)
+		end
+	end
+}
\ No newline at end of file
diff --git a/advtrains/advtrains_luaautomation/textures/atlatc_oppanel.png b/advtrains/advtrains_luaautomation/textures/atlatc_oppanel.png
new file mode 100644
index 0000000..96eb30e
--- /dev/null
+++ b/advtrains/advtrains_luaautomation/textures/atlatc_oppanel.png
diff --git a/advtrains/advtrains_train_steam/init.lua b/advtrains/advtrains_train_steam/init.lua
index e489fd4..16a71f7 100644
--- a/advtrains/advtrains_train_steam/init.lua
+++ b/advtrains/advtrains_train_steam/init.lua
@@ -139,7 +139,7 @@ advtrains.register_wagon("detailed_steam_engine", {
 		})
 	end,
 	drops={"default:steelblock 4"},
-}, S("Detailed Steam Engine"), "advtrains_engine_steam_inv.png")
+}, S("Detailed Steam Engine"), "advtrains_detailed_engine_steam_inv.png")
 
 advtrains.register_wagon("wagon_default", {
 	mesh="advtrains_passenger_wagon.b3d",
@@ -209,24 +209,34 @@ advtrains.register_wagon("wagon_box", {
 minetest.register_craft({
 	output = 'advtrains:newlocomotive',
 	recipe = {
-		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
-		{'default:steelblock', 'dye:black', 'default:steelblock'},
-		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
+		{'', '', 'advtrains:chimney'},
+		{'advtrains:driver_cab', 'dye:black', 'advtrains:boiler'},
+		{'advtrains:wheel', 'advtrains:wheel', 'advtrains:wheel'},
 	},
 })
+
+minetest.register_craft({
+	output = 'advtrains:detailed_steam_engine',
+	recipe = {
+		{'', '', 'advtrains:chimney'},
+		{'advtrains:driver_cab', 'dye:green', 'advtrains:boiler'},
+		{'advtrains:wheel', 'advtrains:wheel', 'advtrains:wheel'},
+	},
+})
+
 minetest.register_craft({
 	output = 'advtrains:wagon_default',
 	recipe = {
 		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
-		{'default:steelblock', 'dye:dark_green', 'default:steelblock'},
-		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
+		{'default:glass', 'dye:dark_green', 'default:glass'},
+		{'advtrains:wheel', 'advtrains:wheel', 'advtrains:wheel'},
 	},
 })
 minetest.register_craft({
 	output = 'advtrains:wagon_box',
 	recipe = {
-		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
-		{'default:steelblock', 'default:chest', 'default:steelblock'},
-		{'default:steelblock', 'default:steelblock', 'default:steelblock'},
+		{'group:wood', 'group:wood', 'group:wood'},
+		{'group:wood', 'default:chest', 'group:wood'},
+		{'advtrains:wheel', '', 'advtrains:wheel'},
 	},
 })
diff --git a/advtrains/advtrains_train_steam/textures/advtrains_detailed_engine_steam_inv.png b/advtrains/advtrains_train_steam/textures/advtrains_detailed_engine_steam_inv.png
new file mode 100644
index 0000000..51adb5a
--- /dev/null
+++ b/advtrains/advtrains_train_steam/textures/advtrains_detailed_engine_steam_inv.png