Remove last files with CR-LF line endings.

3 files changed, 2623 insertions, 2623 deletions

diff --git a/advtrains/helpers.lua b/advtrains/helpers.lua
index 65f25ba..3b0bedd 100644
--- a/advtrains/helpers.lua
+++ b/advtrains/helpers.lua
@@ -1,447 +1,447 @@
---advtrains by orwell96, see readme.txt

-

-local dir_trans_tbl={

-	[0]={x=0, z=1, y=0},

-	[1]={x=1, z=2, y=0},

-	[2]={x=1, z=1, y=0},

-	[3]={x=2, z=1, y=0},

-	[4]={x=1, z=0, y=0},

-	[5]={x=2, z=-1, y=0},

-	[6]={x=1, z=-1, y=0},

-	[7]={x=1, z=-2, y=0},

-	[8]={x=0, z=-1, y=0},

-	[9]={x=-1, z=-2, y=0},

-	[10]={x=-1, z=-1, y=0},

-	[11]={x=-2, z=-1, y=0},

-	[12]={x=-1, z=0, y=0},

-	[13]={x=-2, z=1, y=0},

-	[14]={x=-1, z=1, y=0},

-	[15]={x=-1, z=2, y=0},

-}

-

-local dir_angle_tbl={}

-for d,v in pairs(dir_trans_tbl) do

-	local uvec = vector.normalize(v)

-	dir_angle_tbl[d] = math.atan2(-uvec.x, uvec.z)

-end

-

-

-function advtrains.dir_to_angle(dir)

-	return dir_angle_tbl[dir] or error("advtrains: in helpers.lua/dir_to_angle() given dir="..(dir or "nil"))

-end

-

-function advtrains.dirCoordSet(coord, dir)

-	return vector.add(coord, advtrains.dirToCoord(dir))

-end

-advtrains.pos_add_dir = advtrains.dirCoordSet

-

-function advtrains.pos_add_angle(pos, ang)

-	-- 0 is +Z -> meaning of sin/cos swapped

-	return vector.add(pos, {x = -math.sin(ang), y = 0, z = math.cos(ang)})

-end

-

-function advtrains.dirToCoord(dir)

-	return dir_trans_tbl[dir] or error("advtrains: in helpers.lua/dir_to_vector() given dir="..(dir or "nil"))

-end

-advtrains.dir_to_vector = advtrains.dirToCoord

-

-function advtrains.maxN(list, expectstart)

-	local n=expectstart or 0

-	while list[n] do

-		n=n+1

-	end

-	return n-1

-end

-

-function advtrains.minN(list, expectstart)

-	local n=expectstart or 0

-	while list[n] do

-		n=n-1

-	end

-	return n+1

-end

-

-function atround(number)

-	return math.floor(number+0.5)

-end

-atfloor = math.floor

-

-

-function advtrains.round_vector_floor_y(vec)

-	return {x=math.floor(vec.x+0.5), y=math.floor(vec.y), z=math.floor(vec.z+0.5)}

-end

-

-function advtrains.yawToDirection(yaw, conn1, conn2)

-	if not conn1 or not conn2 then

-		error("given nil to yawToDirection: conn1="..(conn1 or "nil").." conn2="..(conn1 or "nil"))

-	end

-	local yaw1 = advtrains.dir_to_angle(conn1)

-	local yaw2 = advtrains.dir_to_angle(conn2)

-	local adiff1 = advtrains.minAngleDiffRad(yaw, yaw1)

-	local adiff2 = advtrains.minAngleDiffRad(yaw, yaw2)

-	

-	if math.abs(adiff2)<math.abs(adiff1) then

-		return conn2

-	else

-		return conn1

-	end

-end

-

-function advtrains.yawToAnyDir(yaw)

-	local min_conn, min_diff=0, 10

-	for conn, vec in pairs(advtrains.dir_trans_tbl) do

-		local yaw1 = advtrains.dir_to_angle(conn)

-		local diff = math.abs(advtrains.minAngleDiffRad(yaw, yaw1))

-		if diff < min_diff then

-			min_conn = conn

-			min_diff = diff

-		end

-	end

-	return min_conn

-end

-function advtrains.yawToClosestConn(yaw, conns)

-	local min_connid, min_diff=1, 10

-	for connid, conn in ipairs(conns) do

-		local yaw1 = advtrains.dir_to_angle(conn.c)

-		local diff = math.abs(advtrains.minAngleDiffRad(yaw, yaw1))

-		if diff < min_diff then

-			min_connid = connid

-			min_diff = diff

-		end

-	end

-	return min_connid

-end

-

-local pi, pi2 = math.pi, 2*math.pi

-function advtrains.minAngleDiffRad(r1, r2)

-	while r1>pi2 do

-		r1=r1-pi2

-	end

-	while r1<0 do

-		r1=r1+pi2

-	end

-	while r2>pi2 do

-		r2=r2-pi2

-	end

-	while r1<0 do

-		r2=r2+pi2

-	end

-	local try1=r2-r1

-	local try2=r2+pi2-r1

-	local try3=r2-pi2-r1

-	

-	local minabs = math.min(math.abs(try1), math.abs(try2), math.abs(try3))

-	if minabs==math.abs(try1) then

-		return try1

-	end

-	if minabs==math.abs(try2) then

-		return try2

-	end

-	if minabs==math.abs(try3) then

-		return try3

-	end

-end

-

-

--- Takes 2 connections (0...AT_CMAX) as argument

--- Returns the angle median of those 2 positions from the pov

--- of standing on the cdir1 side and looking towards cdir2

--- cdir1 - >NODE> - cdir2

-function advtrains.conn_angle_median(cdir1, cdir2)

-	local ang1 = advtrains.dir_to_angle(advtrains.oppd(cdir1))

-	local ang2 = advtrains.dir_to_angle(cdir2)

-	return ang1 + advtrains.minAngleDiffRad(ang1, ang2)/2

-end

-

-function advtrains.merge_tables(a, ...)

-	local new={}

-	for _,t in ipairs({a,...}) do

-		for k,v in pairs(t) do new[k]=v end

-	end

-	return new

-end

-function advtrains.save_keys(tbl, keys)

-	local new={}

-	for _,key in ipairs(keys) do

-		new[key] = tbl[key]

-	end

-	return new

-end

-

-function advtrains.get_real_index_position(path, index)

-	if not path or not index then return end

-	

-	local first_pos=path[math.floor(index)]

-	local second_pos=path[math.floor(index)+1]

-	

-	if not first_pos or not second_pos then return nil end

-	

-	local factor=index-math.floor(index)

-	local actual_pos={x=first_pos.x-(first_pos.x-second_pos.x)*factor, y=first_pos.y-(first_pos.y-second_pos.y)*factor, z=first_pos.z-(first_pos.z-second_pos.z)*factor,}

-	return actual_pos

-end

-function advtrains.pos_median(pos1, pos2)

-	return {x=pos1.x-(pos1.x-pos2.x)*0.5, y=pos1.y-(pos1.y-pos2.y)*0.5, z=pos1.z-(pos1.z-pos2.z)*0.5}

-end

-function advtrains.abs_ceil(i)

-	return math.ceil(math.abs(i))*math.sign(i)

-end

-

-function advtrains.serialize_inventory(inv)

-	local ser={}

-	local liszts=inv:get_lists()

-	for lisztname, liszt in pairs(liszts) do

-		ser[lisztname]={}

-		for idx, item in ipairs(liszt) do

-			local istring=item:to_string()

-			if istring~="" then

-				ser[lisztname][idx]=istring

-			end

-		end

-	end

-	return minetest.serialize(ser)

-end

-function advtrains.deserialize_inventory(sers, inv)

-	local ser=minetest.deserialize(sers)

-	if ser then

-		inv:set_lists(ser)

-		return true

-	end

-	return false

-end

-

---is_protected wrapper that checks for protection_bypass privilege

-function advtrains.is_protected(pos, name)

-	if not name then

-		error("advtrains.is_protected() called without name parameter!")

-	end

-	if minetest.check_player_privs(name, {protection_bypass=true}) then

-		--player can bypass protection

-		return false

-	end

-	return minetest.is_protected(pos, name)

-end

-

-function advtrains.is_creative(name)

-	if not name then

-		error("advtrains.is_creative() called without name parameter!")

-	end

-	if minetest.check_player_privs(name, {creative=true}) then

-		return true

-	end

-	return minetest.settings:get_bool("creative_mode")

-end

-

-function advtrains.is_damage_enabled(name)

-	if not name then

-		error("advtrains.is_damage_enabled() called without name parameter!")

-	end

-	if minetest.check_player_privs(name, "train_admin") then

-		return false

-	end

-	return minetest.settings:get_bool("enable_damage")

-end

-

-function advtrains.ms_to_kmh(speed)

-	return speed * 3.6

-end

-

--- 4 possible inputs:

--- integer: just do that modulo calculation

--- table with c set: rotate c

--- table with tables: rotate each

--- table with integers: rotate each (probably no use case)

-function advtrains.rotate_conn_by(conn, rotate)

-	if tonumber(conn) then

-		return (conn+rotate)%AT_CMAX

-	elseif conn.c then

-		return { c = (conn.c+rotate)%AT_CMAX, y = conn.y}

-	end

-	local tmp={}

-	for connid, data in ipairs(conn) do

-		tmp[connid]=advtrains.rotate_conn_by(data, rotate)

-	end

-	return tmp

-end

-

-

-function advtrains.oppd(dir)

-	return advtrains.rotate_conn_by(dir, AT_CMAX/2)

-end

---conn_to_match like rotate_conn_by

---other_conns have to be a table of conn tables!

-function advtrains.conn_matches_to(conn, other_conns)

-	if tonumber(conn) then

-		for connid, data in ipairs(other_conns) do

-			if advtrains.oppd(conn) == data.c then return connid end

-		end

-		return false

-	elseif conn.c then

-		for connid, data in ipairs(other_conns) do

-			local cmp = advtrains.oppd(conn)

-			if cmp.c == data.c and (cmp.y or 0) == (data.y or 0) then return connid end

-		end

-		return false

-	end

-	local tmp={}

-	for connid, data in ipairs(conn) do

-		local backmatch = advtrains.conn_matches_to(data, other_conns)

-		if backmatch then return backmatch, connid end --returns <connid of other rail> <connid of this rail>

-	end

-	return false

-end

-

--- Going from the rail at pos (does not need to be rounded) along connection with id conn_idx, if there is a matching rail, return it and the matching connid

--- returns: <adjacent pos>, <conn index of adjacent>, <my conn index>, <railheight of adjacent>

--- parameter this_conns_p is connection table of this rail and is optional, is determined by get_rail_info_at if not provided.

-function advtrains.get_adjacent_rail(this_posnr, this_conns_p, conn_idx, drives_on)

-	local this_pos = advtrains.round_vector_floor_y(this_posnr)

-	local this_conns = this_conns_p

-	if not this_conns then

-		_, this_conns = advtrains.get_rail_info_at(this_pos)

-	end

-	if not conn_idx then

-		for coni, _ in ipairs(this_conns) do

-			local adj_pos, adj_conn_idx, _, nry, nco = advtrains.get_adjacent_rail(this_pos, this_conns, coni)

-			if adj_pos then return adj_pos,adj_conn_idx,coni,nry, nco end

-		end

-		return nil

-	end

-	

-	local conn = this_conns[conn_idx]

-	local conn_y = conn.y or 0

-	local adj_pos = advtrains.dirCoordSet(this_pos, conn.c);

-	

-	while conn_y>=1 do

-		conn_y = conn_y - 1

-		adj_pos.y = adj_pos.y + 1

-	end

-	

-	local nextnode_ok, nextconns, nextrail_y=advtrains.get_rail_info_at(adj_pos, drives_on)

-	if not nextnode_ok then

-		adj_pos.y = adj_pos.y - 1

-		conn_y = conn_y + 1

-		nextnode_ok, nextconns, nextrail_y=advtrains.get_rail_info_at(adj_pos, drives_on)

-		if not nextnode_ok then

-			return nil

-		end

-	end

-	local adj_connid = advtrains.conn_matches_to({c=conn.c, y=conn_y}, nextconns)

-	if adj_connid then

-		return adj_pos, adj_connid, conn_idx, nextrail_y, nextconns

-	end

-	return nil

-end

-

--- when a train enters a rail on connid 'conn', which connid will it go out?

--- nconns: number of connections in connection table:

--- 2 = straight rail; 3 = turnout, 4 = crossing, 5 = three-way turnout (5th entry is a stub)

--- returns: connid_out

-local connlku={[2]={2,1}, [3]={2,1,1}, [4]={2,1,4,3}, [5]={2,1,1,1}}

-function advtrains.get_matching_conn(conn, nconns)

-	return connlku[nconns][conn]

-end

-

-function advtrains.random_id()

-	local idst=""

-	for i=0,5 do

-		idst=idst..(math.random(0,9))

-	end

-	return idst

-end

--- Shorthand for pos_to_string and round_vector_floor_y

-function advtrains.roundfloorpts(pos)

-	return minetest.pos_to_string(advtrains.round_vector_floor_y(pos))

-end

-

--- insert an element into a table if it does not yet exist there

--- equalfunc is a function to compare equality, defaults to ==

--- returns true if the element was inserted

-function advtrains.insert_once(tab, elem, equalfunc)

-	for _,e in pairs(tab) do

-		if equalfunc and equalfunc(elem, e) or e==elem then return false end

-	end

-	tab[#tab+1] = elem

-	return true

-end

-

-local hext = { [0]="0",[1]="1",[2]="2",[3]="3",[4]="4",[5]="5",[6]="6",[7]="7",[8]="8",[9]="9",[10]="A",[11]="B",[12]="C",[13]="D",[14]="E",[15]="F"}

-local dect = { ["0"]=0,["1"]=1,["2"]=2,["3"]=3,["4"]=4,["5"]=5,["6"]=6,["7"]=7,["8"]=8,["9"]=9,["A"]=10,["B"]=11,["C"]=12,["D"]=13,["E"]=14,["F"]=15}

-

-local f = atfloor

-

-local function hex(i)

-	local x=i+32768

-	local c4 = x % 16

-	x = f(x / 16)

-	local c3 = x % 16

-	x = f(x / 16)

-	local c2 = x % 16

-	x = f(x / 16)

-	local c1 = x % 16

-	return (hext[c1]) .. (hext[c2]) .. (hext[c3]) .. (hext[c4])

-end

-

-local function c(s,i) return dect[string.sub(s,i,i)] end

-

-local function dec(s)

-	return (c(s,1)*4096 + c(s,2)*256 + c(s,3)*16 + c(s,4))-32768

-end

--- Takes a position vector and outputs a encoded value suitable as table index

--- This is essentially a hexadecimal representation of the position (+32768)

--- Order (YYY)YXXXXZZZZ

-function advtrains.encode_pos(pos)

-	return hex(pos.y) .. hex(pos.x) .. hex(pos.z)

-end

-

--- decodes a position encoded with encode_pos

-function advtrains.decode_pos(pts)

-	if not pts or not #pts==6 then return nil end

-	local stry = string.sub(pts, 1,4)

-	local strx = string.sub(pts, 5,8)

-	local strz = string.sub(pts, 9,12)

-	return vector.new(dec(strx), dec(stry), dec(strz))

-end

-

---[[ Benchmarking code

-local tdt = {}

-local tlt = {}

-local tet = {}

-

-for i=1,1000000 do

-	tdt[i] = vector.new(math.random(-65536, 65535), math.random(-65536, 65535), math.random(-65536, 65535))

-	if i%1000 == 0 then

-		tlt[#tlt+1] = tdt[i]

-	end

-end

-

-local t1=os.clock()

-for i=1,1000000 do

-	local pe = advtrains.encode_pos(tdt[i])

-	local pb = advtrains.decode_pos(pe)

-	tet[pe] = i

-end

-for i,v in ipairs(tlt) do

-	local lk = tet[advtrains.encode_pos(v)]

-end

-atdebug("endec",os.clock()-t1,"s")

-

-tet = {}

-

-t1=os.clock()

-for i=1,1000000 do

-	local pe = minetest.pos_to_string(tdt[i])

-	local pb = minetest.string_to_pos(pe)

-	tet[pe] = i

-end

-for i,v in ipairs(tlt) do

-	local lk = tet[minetest.pos_to_string(v)]

-end

-atdebug("pts",os.clock()-t1,"s")

-

---Results:

---2018-11-29 16:57:08: ACTION[Main]: [advtrains]endec 1.786451 s 

---2018-11-29 16:57:10: ACTION[Main]: [advtrains]pts 2.566377 s 

-]]

-

-

+--advtrains by orwell96, see readme.txt
+
+local dir_trans_tbl={
+	[0]={x=0, z=1, y=0},
+	[1]={x=1, z=2, y=0},
+	[2]={x=1, z=1, y=0},
+	[3]={x=2, z=1, y=0},
+	[4]={x=1, z=0, y=0},
+	[5]={x=2, z=-1, y=0},
+	[6]={x=1, z=-1, y=0},
+	[7]={x=1, z=-2, y=0},
+	[8]={x=0, z=-1, y=0},
+	[9]={x=-1, z=-2, y=0},
+	[10]={x=-1, z=-1, y=0},
+	[11]={x=-2, z=-1, y=0},
+	[12]={x=-1, z=0, y=0},
+	[13]={x=-2, z=1, y=0},
+	[14]={x=-1, z=1, y=0},
+	[15]={x=-1, z=2, y=0},
+}
+
+local dir_angle_tbl={}
+for d,v in pairs(dir_trans_tbl) do
+	local uvec = vector.normalize(v)
+	dir_angle_tbl[d] = math.atan2(-uvec.x, uvec.z)
+end
+
+
+function advtrains.dir_to_angle(dir)
+	return dir_angle_tbl[dir] or error("advtrains: in helpers.lua/dir_to_angle() given dir="..(dir or "nil"))
+end
+
+function advtrains.dirCoordSet(coord, dir)
+	return vector.add(coord, advtrains.dirToCoord(dir))
+end
+advtrains.pos_add_dir = advtrains.dirCoordSet
+
+function advtrains.pos_add_angle(pos, ang)
+	-- 0 is +Z -> meaning of sin/cos swapped
+	return vector.add(pos, {x = -math.sin(ang), y = 0, z = math.cos(ang)})
+end
+
+function advtrains.dirToCoord(dir)
+	return dir_trans_tbl[dir] or error("advtrains: in helpers.lua/dir_to_vector() given dir="..(dir or "nil"))
+end
+advtrains.dir_to_vector = advtrains.dirToCoord
+
+function advtrains.maxN(list, expectstart)
+	local n=expectstart or 0
+	while list[n] do
+		n=n+1
+	end
+	return n-1
+end
+
+function advtrains.minN(list, expectstart)
+	local n=expectstart or 0
+	while list[n] do
+		n=n-1
+	end
+	return n+1
+end
+
+function atround(number)
+	return math.floor(number+0.5)
+end
+atfloor = math.floor
+
+
+function advtrains.round_vector_floor_y(vec)
+	return {x=math.floor(vec.x+0.5), y=math.floor(vec.y), z=math.floor(vec.z+0.5)}
+end
+
+function advtrains.yawToDirection(yaw, conn1, conn2)
+	if not conn1 or not conn2 then
+		error("given nil to yawToDirection: conn1="..(conn1 or "nil").." conn2="..(conn1 or "nil"))
+	end
+	local yaw1 = advtrains.dir_to_angle(conn1)
+	local yaw2 = advtrains.dir_to_angle(conn2)
+	local adiff1 = advtrains.minAngleDiffRad(yaw, yaw1)
+	local adiff2 = advtrains.minAngleDiffRad(yaw, yaw2)
+	
+	if math.abs(adiff2)<math.abs(adiff1) then
+		return conn2
+	else
+		return conn1
+	end
+end
+
+function advtrains.yawToAnyDir(yaw)
+	local min_conn, min_diff=0, 10
+	for conn, vec in pairs(advtrains.dir_trans_tbl) do
+		local yaw1 = advtrains.dir_to_angle(conn)
+		local diff = math.abs(advtrains.minAngleDiffRad(yaw, yaw1))
+		if diff < min_diff then
+			min_conn = conn
+			min_diff = diff
+		end
+	end
+	return min_conn
+end
+function advtrains.yawToClosestConn(yaw, conns)
+	local min_connid, min_diff=1, 10
+	for connid, conn in ipairs(conns) do
+		local yaw1 = advtrains.dir_to_angle(conn.c)
+		local diff = math.abs(advtrains.minAngleDiffRad(yaw, yaw1))
+		if diff < min_diff then
+			min_connid = connid
+			min_diff = diff
+		end
+	end
+	return min_connid
+end
+
+local pi, pi2 = math.pi, 2*math.pi
+function advtrains.minAngleDiffRad(r1, r2)
+	while r1>pi2 do
+		r1=r1-pi2
+	end
+	while r1<0 do
+		r1=r1+pi2
+	end
+	while r2>pi2 do
+		r2=r2-pi2
+	end
+	while r1<0 do
+		r2=r2+pi2
+	end
+	local try1=r2-r1
+	local try2=r2+pi2-r1
+	local try3=r2-pi2-r1
+	
+	local minabs = math.min(math.abs(try1), math.abs(try2), math.abs(try3))
+	if minabs==math.abs(try1) then
+		return try1
+	end
+	if minabs==math.abs(try2) then
+		return try2
+	end
+	if minabs==math.abs(try3) then
+		return try3
+	end
+end
+
+
+-- Takes 2 connections (0...AT_CMAX) as argument
+-- Returns the angle median of those 2 positions from the pov
+-- of standing on the cdir1 side and looking towards cdir2
+-- cdir1 - >NODE> - cdir2
+function advtrains.conn_angle_median(cdir1, cdir2)
+	local ang1 = advtrains.dir_to_angle(advtrains.oppd(cdir1))
+	local ang2 = advtrains.dir_to_angle(cdir2)
+	return ang1 + advtrains.minAngleDiffRad(ang1, ang2)/2
+end
+
+function advtrains.merge_tables(a, ...)
+	local new={}
+	for _,t in ipairs({a,...}) do
+		for k,v in pairs(t) do new[k]=v end
+	end
+	return new
+end
+function advtrains.save_keys(tbl, keys)
+	local new={}
+	for _,key in ipairs(keys) do
+		new[key] = tbl[key]
+	end
+	return new
+end
+
+function advtrains.get_real_index_position(path, index)
+	if not path or not index then return end
+	
+	local first_pos=path[math.floor(index)]
+	local second_pos=path[math.floor(index)+1]
+	
+	if not first_pos or not second_pos then return nil end
+	
+	local factor=index-math.floor(index)
+	local actual_pos={x=first_pos.x-(first_pos.x-second_pos.x)*factor, y=first_pos.y-(first_pos.y-second_pos.y)*factor, z=first_pos.z-(first_pos.z-second_pos.z)*factor,}
+	return actual_pos
+end
+function advtrains.pos_median(pos1, pos2)
+	return {x=pos1.x-(pos1.x-pos2.x)*0.5, y=pos1.y-(pos1.y-pos2.y)*0.5, z=pos1.z-(pos1.z-pos2.z)*0.5}
+end
+function advtrains.abs_ceil(i)
+	return math.ceil(math.abs(i))*math.sign(i)
+end
+
+function advtrains.serialize_inventory(inv)
+	local ser={}
+	local liszts=inv:get_lists()
+	for lisztname, liszt in pairs(liszts) do
+		ser[lisztname]={}
+		for idx, item in ipairs(liszt) do
+			local istring=item:to_string()
+			if istring~="" then
+				ser[lisztname][idx]=istring
+			end
+		end
+	end
+	return minetest.serialize(ser)
+end
+function advtrains.deserialize_inventory(sers, inv)
+	local ser=minetest.deserialize(sers)
+	if ser then
+		inv:set_lists(ser)
+		return true
+	end
+	return false
+end
+
+--is_protected wrapper that checks for protection_bypass privilege
+function advtrains.is_protected(pos, name)
+	if not name then
+		error("advtrains.is_protected() called without name parameter!")
+	end
+	if minetest.check_player_privs(name, {protection_bypass=true}) then
+		--player can bypass protection
+		return false
+	end
+	return minetest.is_protected(pos, name)
+end
+
+function advtrains.is_creative(name)
+	if not name then
+		error("advtrains.is_creative() called without name parameter!")
+	end
+	if minetest.check_player_privs(name, {creative=true}) then
+		return true
+	end
+	return minetest.settings:get_bool("creative_mode")
+end
+
+function advtrains.is_damage_enabled(name)
+	if not name then
+		error("advtrains.is_damage_enabled() called without name parameter!")
+	end
+	if minetest.check_player_privs(name, "train_admin") then
+		return false
+	end
+	return minetest.settings:get_bool("enable_damage")
+end
+
+function advtrains.ms_to_kmh(speed)
+	return speed * 3.6
+end
+
+-- 4 possible inputs:
+-- integer: just do that modulo calculation
+-- table with c set: rotate c
+-- table with tables: rotate each
+-- table with integers: rotate each (probably no use case)
+function advtrains.rotate_conn_by(conn, rotate)
+	if tonumber(conn) then
+		return (conn+rotate)%AT_CMAX
+	elseif conn.c then
+		return { c = (conn.c+rotate)%AT_CMAX, y = conn.y}
+	end
+	local tmp={}
+	for connid, data in ipairs(conn) do
+		tmp[connid]=advtrains.rotate_conn_by(data, rotate)
+	end
+	return tmp
+end
+
+
+function advtrains.oppd(dir)
+	return advtrains.rotate_conn_by(dir, AT_CMAX/2)
+end
+--conn_to_match like rotate_conn_by
+--other_conns have to be a table of conn tables!
+function advtrains.conn_matches_to(conn, other_conns)
+	if tonumber(conn) then
+		for connid, data in ipairs(other_conns) do
+			if advtrains.oppd(conn) == data.c then return connid end
+		end
+		return false
+	elseif conn.c then
+		for connid, data in ipairs(other_conns) do
+			local cmp = advtrains.oppd(conn)
+			if cmp.c == data.c and (cmp.y or 0) == (data.y or 0) then return connid end
+		end
+		return false
+	end
+	local tmp={}
+	for connid, data in ipairs(conn) do
+		local backmatch = advtrains.conn_matches_to(data, other_conns)
+		if backmatch then return backmatch, connid end --returns <connid of other rail> <connid of this rail>
+	end
+	return false
+end
+
+-- Going from the rail at pos (does not need to be rounded) along connection with id conn_idx, if there is a matching rail, return it and the matching connid
+-- returns: <adjacent pos>, <conn index of adjacent>, <my conn index>, <railheight of adjacent>
+-- parameter this_conns_p is connection table of this rail and is optional, is determined by get_rail_info_at if not provided.
+function advtrains.get_adjacent_rail(this_posnr, this_conns_p, conn_idx, drives_on)
+	local this_pos = advtrains.round_vector_floor_y(this_posnr)
+	local this_conns = this_conns_p
+	if not this_conns then
+		_, this_conns = advtrains.get_rail_info_at(this_pos)
+	end
+	if not conn_idx then
+		for coni, _ in ipairs(this_conns) do
+			local adj_pos, adj_conn_idx, _, nry, nco = advtrains.get_adjacent_rail(this_pos, this_conns, coni)
+			if adj_pos then return adj_pos,adj_conn_idx,coni,nry, nco end
+		end
+		return nil
+	end
+	
+	local conn = this_conns[conn_idx]
+	local conn_y = conn.y or 0
+	local adj_pos = advtrains.dirCoordSet(this_pos, conn.c);
+	
+	while conn_y>=1 do
+		conn_y = conn_y - 1
+		adj_pos.y = adj_pos.y + 1
+	end
+	
+	local nextnode_ok, nextconns, nextrail_y=advtrains.get_rail_info_at(adj_pos, drives_on)
+	if not nextnode_ok then
+		adj_pos.y = adj_pos.y - 1
+		conn_y = conn_y + 1
+		nextnode_ok, nextconns, nextrail_y=advtrains.get_rail_info_at(adj_pos, drives_on)
+		if not nextnode_ok then
+			return nil
+		end
+	end
+	local adj_connid = advtrains.conn_matches_to({c=conn.c, y=conn_y}, nextconns)
+	if adj_connid then
+		return adj_pos, adj_connid, conn_idx, nextrail_y, nextconns
+	end
+	return nil
+end
+
+-- when a train enters a rail on connid 'conn', which connid will it go out?
+-- nconns: number of connections in connection table:
+-- 2 = straight rail; 3 = turnout, 4 = crossing, 5 = three-way turnout (5th entry is a stub)
+-- returns: connid_out
+local connlku={[2]={2,1}, [3]={2,1,1}, [4]={2,1,4,3}, [5]={2,1,1,1}}
+function advtrains.get_matching_conn(conn, nconns)
+	return connlku[nconns][conn]
+end
+
+function advtrains.random_id()
+	local idst=""
+	for i=0,5 do
+		idst=idst..(math.random(0,9))
+	end
+	return idst
+end
+-- Shorthand for pos_to_string and round_vector_floor_y
+function advtrains.roundfloorpts(pos)
+	return minetest.pos_to_string(advtrains.round_vector_floor_y(pos))
+end
+
+-- insert an element into a table if it does not yet exist there
+-- equalfunc is a function to compare equality, defaults to ==
+-- returns true if the element was inserted
+function advtrains.insert_once(tab, elem, equalfunc)
+	for _,e in pairs(tab) do
+		if equalfunc and equalfunc(elem, e) or e==elem then return false end
+	end
+	tab[#tab+1] = elem
+	return true
+end
+
+local hext = { [0]="0",[1]="1",[2]="2",[3]="3",[4]="4",[5]="5",[6]="6",[7]="7",[8]="8",[9]="9",[10]="A",[11]="B",[12]="C",[13]="D",[14]="E",[15]="F"}
+local dect = { ["0"]=0,["1"]=1,["2"]=2,["3"]=3,["4"]=4,["5"]=5,["6"]=6,["7"]=7,["8"]=8,["9"]=9,["A"]=10,["B"]=11,["C"]=12,["D"]=13,["E"]=14,["F"]=15}
+
+local f = atfloor
+
+local function hex(i)
+	local x=i+32768
+	local c4 = x % 16
+	x = f(x / 16)
+	local c3 = x % 16
+	x = f(x / 16)
+	local c2 = x % 16
+	x = f(x / 16)
+	local c1 = x % 16
+	return (hext[c1]) .. (hext[c2]) .. (hext[c3]) .. (hext[c4])
+end
+
+local function c(s,i) return dect[string.sub(s,i,i)] end
+
+local function dec(s)
+	return (c(s,1)*4096 + c(s,2)*256 + c(s,3)*16 + c(s,4))-32768
+end
+-- Takes a position vector and outputs a encoded value suitable as table index
+-- This is essentially a hexadecimal representation of the position (+32768)
+-- Order (YYY)YXXXXZZZZ
+function advtrains.encode_pos(pos)
+	return hex(pos.y) .. hex(pos.x) .. hex(pos.z)
+end
+
+-- decodes a position encoded with encode_pos
+function advtrains.decode_pos(pts)
+	if not pts or not #pts==6 then return nil end
+	local stry = string.sub(pts, 1,4)
+	local strx = string.sub(pts, 5,8)
+	local strz = string.sub(pts, 9,12)
+	return vector.new(dec(strx), dec(stry), dec(strz))
+end
+
+--[[ Benchmarking code
+local tdt = {}
+local tlt = {}
+local tet = {}
+
+for i=1,1000000 do
+	tdt[i] = vector.new(math.random(-65536, 65535), math.random(-65536, 65535), math.random(-65536, 65535))
+	if i%1000 == 0 then
+		tlt[#tlt+1] = tdt[i]
+	end
+end
+
+local t1=os.clock()
+for i=1,1000000 do
+	local pe = advtrains.encode_pos(tdt[i])
+	local pb = advtrains.decode_pos(pe)
+	tet[pe] = i
+end
+for i,v in ipairs(tlt) do
+	local lk = tet[advtrains.encode_pos(v)]
+end
+atdebug("endec",os.clock()-t1,"s")
+
+tet = {}
+
+t1=os.clock()
+for i=1,1000000 do
+	local pe = minetest.pos_to_string(tdt[i])
+	local pb = minetest.string_to_pos(pe)
+	tet[pe] = i
+end
+for i,v in ipairs(tlt) do
+	local lk = tet[minetest.pos_to_string(v)]
+end
+atdebug("pts",os.clock()-t1,"s")
+
+--Results:
+--2018-11-29 16:57:08: ACTION[Main]: [advtrains]endec 1.786451 s 
+--2018-11-29 16:57:10: ACTION[Main]: [advtrains]pts 2.566377 s 
+]]
+
+
diff --git a/advtrains/tracks.lua b/advtrains/tracks.lua
index 549363d..60969df 100644
--- a/advtrains/tracks.lua
+++ b/advtrains/tracks.lua
@@ -1,742 +1,742 @@
---advtrains by orwell96, see readme.txt

-

---dev-time settings:

---EDIT HERE

---If the old non-model rails on straight tracks should be replaced by the new...

---false: no

---true: yes

-advtrains.register_replacement_lbms=false

-

---[[TracksDefinition

-nodename_prefix

-texture_prefix

-description

-common={}

-straight={}

-straight45={}

-curve={}

-curve45={}

-lswitchst={}

-lswitchst45={}

-rswitchst={}

-rswitchst45={}

-lswitchcr={}

-lswitchcr45={}

-rswitchcr={}

-rswitchcr45={}

-vert1={

-	--you'll probably want to override mesh here

-}

-vert2={

-	--you'll probably want to override mesh here

-}

-]]--

-advtrains.all_tracktypes={}

-

---definition preparation

-local function conns(c1, c2, r1, r2) return {{c=c1, y=r1}, {c=c2, y=r2}} end

-local function conns3(c1, c2, c3, r1, r2, r3) return {{c=c1, y=r1}, {c=c2, y=r2}, {c=c3, y=r3}} end

-

-advtrains.ap={}

-advtrains.ap.t_30deg_flat={

-	regstep=1,

-	variant={

-		st={

-			conns = conns(0,8),

-			desc = "straight",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "cr",

-		},

-		cr={

-			conns = conns(0,7),

-			desc = "curve",

-			tpdouble = true,

-			trackworker = "swlst",

-		},

-		swlst={

-			conns = conns3(0,8,7),

-			desc = "left switch (straight)",

-			trackworker = "swrst",

-			switchalt = "cr",

-			switchmc = "on",

-			switchst = "st",

-			switchprefix = "swl",

-		},

-		swlcr={

-			conns = conns3(0,7,8),

-			desc = "left switch (curve)",

-			trackworker = "swrcr",

-			switchalt = "st",

-			switchmc = "off",

-			switchst = "cr",

-			switchprefix = "swl",

-		},

-		swrst={

-			conns = conns3(0,8,9),

-			desc = "right switch (straight)",

-			trackworker = "st",

-			switchalt = "cr",

-			switchmc = "on",

-			switchst = "st",

-			switchprefix = "swr",

-		},

-		swrcr={

-			conns = conns3(0,9,8),

-			desc = "right switch (curve)",

-			trackworker = "st",

-			switchalt = "st",

-			switchmc = "off",

-			switchst = "cr",

-			switchprefix = "swr",

-		},

-	},

-	regtp=true,

-	tpdefault="st",

-	trackworker={

-		["swrcr"]="st",

-		["swrst"]="st",

-		["cr"]="swlst",

-		["swlcr"]="swrcr",

-		["swlst"]="swrst",

-	},

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_yturnout={

-	regstep=1,

-	variant={

-		l={

-			conns = conns3(0,7,9),

-			desc = "Y-turnout (left)",

-			switchalt = "r",

-			switchmc = "off",

-			switchst = "l",

-			switchprefix = "",

-		},

-		r={

-			conns = conns3(0,9,7),

-			desc = "Y-turnout (right)",

-			switchalt = "l",

-			switchmc = "on",

-			switchst = "r",

-			switchprefix = "",

-		}

-	},

-	regtp=true,

-	tpdefault="l",

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_s3way={

-	regstep=1,

-	variant={

-		l={

+--advtrains by orwell96, see readme.txt
+
+--dev-time settings:
+--EDIT HERE
+--If the old non-model rails on straight tracks should be replaced by the new...
+--false: no
+--true: yes
+advtrains.register_replacement_lbms=false
+
+--[[TracksDefinition
+nodename_prefix
+texture_prefix
+description
+common={}
+straight={}
+straight45={}
+curve={}
+curve45={}
+lswitchst={}
+lswitchst45={}
+rswitchst={}
+rswitchst45={}
+lswitchcr={}
+lswitchcr45={}
+rswitchcr={}
+rswitchcr45={}
+vert1={
+	--you'll probably want to override mesh here
+}
+vert2={
+	--you'll probably want to override mesh here
+}
+]]--
+advtrains.all_tracktypes={}
+
+--definition preparation
+local function conns(c1, c2, r1, r2) return {{c=c1, y=r1}, {c=c2, y=r2}} end
+local function conns3(c1, c2, c3, r1, r2, r3) return {{c=c1, y=r1}, {c=c2, y=r2}, {c=c3, y=r3}} end
+
+advtrains.ap={}
+advtrains.ap.t_30deg_flat={
+	regstep=1,
+	variant={
+		st={
+			conns = conns(0,8),
+			desc = "straight",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "cr",
+		},
+		cr={
+			conns = conns(0,7),
+			desc = "curve",
+			tpdouble = true,
+			trackworker = "swlst",
+		},
+		swlst={
+			conns = conns3(0,8,7),
+			desc = "left switch (straight)",
+			trackworker = "swrst",
+			switchalt = "cr",
+			switchmc = "on",
+			switchst = "st",
+			switchprefix = "swl",
+		},
+		swlcr={
+			conns = conns3(0,7,8),
+			desc = "left switch (curve)",
+			trackworker = "swrcr",
+			switchalt = "st",
+			switchmc = "off",
+			switchst = "cr",
+			switchprefix = "swl",
+		},
+		swrst={
+			conns = conns3(0,8,9),
+			desc = "right switch (straight)",
+			trackworker = "st",
+			switchalt = "cr",
+			switchmc = "on",
+			switchst = "st",
+			switchprefix = "swr",
+		},
+		swrcr={
+			conns = conns3(0,9,8),
+			desc = "right switch (curve)",
+			trackworker = "st",
+			switchalt = "st",
+			switchmc = "off",
+			switchst = "cr",
+			switchprefix = "swr",
+		},
+	},
+	regtp=true,
+	tpdefault="st",
+	trackworker={
+		["swrcr"]="st",
+		["swrst"]="st",
+		["cr"]="swlst",
+		["swlcr"]="swrcr",
+		["swlst"]="swrst",
+	},
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_yturnout={
+	regstep=1,
+	variant={
+		l={
+			conns = conns3(0,7,9),
+			desc = "Y-turnout (left)",
+			switchalt = "r",
+			switchmc = "off",
+			switchst = "l",
+			switchprefix = "",
+		},
+		r={
+			conns = conns3(0,9,7),
+			desc = "Y-turnout (right)",
+			switchalt = "l",
+			switchmc = "on",
+			switchst = "r",
+			switchprefix = "",
+		}
+	},
+	regtp=true,
+	tpdefault="l",
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_s3way={
+	regstep=1,
+	variant={
+		l={
 			conns = { {c=0}, {c=7}, {c=8}, {c=9}, {c=0} },
-			desc = "3-way turnout (left)",

-			switchalt = "s",

-			switchst="l",

-			switchprefix = "",

-		},

-		s={

+			desc = "3-way turnout (left)",
+			switchalt = "s",
+			switchst="l",
+			switchprefix = "",
+		},
+		s={
 			conns = { {c=0}, {c=8}, {c=7}, {c=9}, {c=0} },
-			desc = "3-way turnout (straight)",

-			switchalt ="r",

-			switchst = "s",

-			switchprefix = "",

-		},

-		r={

+			desc = "3-way turnout (straight)",
+			switchalt ="r",
+			switchst = "s",
+			switchprefix = "",
+		},
+		r={
 			conns = { {c=0}, {c=9}, {c=8}, {c=7}, {c=0} },
-			desc = "3-way turnout (right)",

-			switchalt = "l",

-			switchst="r",

-			switchprefix = "",

-		}

-	},

-	regtp=true,

-	tpdefault="l",

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_30deg_slope={

-	regstep=1,

-	variant={

-		vst1={conns = conns(8,0,0,0.5), rail_y = 0.25, desc = "steep uphill 1/2", slope=true},

-		vst2={conns = conns(8,0,0.5,1), rail_y = 0.75, desc = "steep uphill 2/2", slope=true},

-		vst31={conns = conns(8,0,0,0.33), rail_y = 0.16, desc = "uphill 1/3", slope=true},

-		vst32={conns = conns(8,0,0.33,0.66), rail_y = 0.5, desc = "uphill 2/3", slope=true},

-		vst33={conns = conns(8,0,0.66,1), rail_y = 0.83, desc = "uphill 3/3", slope=true},

-	},

-	regsp=true,

-	slopeplacer={

-		[2]={"vst1", "vst2"},

-		[3]={"vst31", "vst32", "vst33"},

-		max=3,--highest entry

-	},

-	slopeplacer_45={

-		[2]={"vst1_45", "vst2_45"},

-		max=2,

-	},

-	rotation={"", "_30", "_45", "_60"},

-	trackworker={},

-	increativeinv={},

-}

-advtrains.ap.t_30deg_straightonly={

-	regstep=1,

-	variant={

-		st={

-			conns = conns(0,8),

-			desc = "straight",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "st",

-		},

-	},

-	regtp=true,

-	tpdefault="st",

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_30deg_straightonly_noplacer={

-	regstep=1,

-	variant={

-		st={

-			conns = conns(0,8),

-			desc = "straight",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "st",

-		},

-	},

-	tpdefault="st",

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_45deg={

-	regstep=2,

-	variant={

-		st={

-			conns = conns(0,8),

-			desc = "straight",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "cr",

-		},

-		cr={

-			conns = conns(0,6),

-			desc = "curve",

-			tpdouble = true,

-			trackworker = "swlst",

-		},

-		swlst={

-			conns = conns3(0,8,6),

-			desc = "left switch (straight)",

-			trackworker = "swrst",

-			switchalt = "cr",

-			switchmc = "on",

-			switchst = "st",

-		},

-		swlcr={

-			conns = conns3(0,6,8),

-			desc = "left switch (curve)",

-			trackworker = "swrcr",

-			switchalt = "st",

-			switchmc = "off",

-			switchst = "cr",

-		},

-		swrst={

-			conns = conns3(0,8,10),

-			desc = "right switch (straight)",

-			trackworker = "st",

-			switchalt = "cr",

-			switchmc = "on",

-			switchst = "st",

-		},

-		swrcr={

-			conns = conns3(0,10,8),

-			desc = "right switch (curve)",

-			trackworker = "st",

-			switchalt = "st",

-			switchmc = "off",

-			switchst = "cr",

-		},

-	},

-	regtp=true,

-	tpdefault="st",

-	trackworker={

-		["swrcr"]="st",

-		["swrst"]="st",

-		["cr"]="swlst",

-		["swlcr"]="swrcr",

-		["swlst"]="swrst",

-	},

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_perpcrossing={

-	regstep = 1,

-	variant={

-		st={

-			conns = { {c=0}, {c=8}, {c=4}, {c=12} },

-			desc = "perpendicular crossing",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "st",

-		},

-	},

-	regtp=true,

-	tpdefault="st",

-	rotation={"", "_30", "_45", "_60"},

-}

-advtrains.ap.t_90plusx_crossing={

-	regstep = 1,

-	variant={

-		["30l"]={

-			conns = { {c=0}, {c=8}, {c=1}, {c=9} },

-			desc = "30/90 degree crossing (left)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "45l"

-		},

-		["45l"]={

-			conns = { {c=0}, {c=8}, {c=2}, {c=10} },

-			desc = "45/90 degree crossing (left)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "60l",

-		},

-		["60l"]={

-			conns = { {c=0}, {c=8}, {c=3}, {c=11}},

-			desc = "60/90 degree crossing (left)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "60r",

-		},

-		["60r"]={

-			conns = { {c=0}, {c=8}, {c=7}, {c=15} },

-			desc = "60/90 degree crossing (right)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "45r"

-		},

-		["45r"]={

-			conns = { {c=0}, {c=8}, {c=6}, {c=14} },

-			desc = "45/90 degree crossing (right)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "30r",

-		},

-		["30r"]={

-			conns = { {c=0}, {c=8}, {c=7}, {c=15}},

-			desc = "30/90 degree crossing (right)",

-			tpdouble = true,

-			tpsingle = true,

-			trackworker = "30l",

-		},

-	},

-	regtp=true,

-	tpdefault="30l",

-	rotation={""},

-	trackworker = {

-		["30l"] = "45l",

-		["45l"] = "60l",

-		["60l"] = "60r",

-		["60r"] = "45r",

-		["45r"] = "30r",

-		["30r"] = "30l",

-	}

-}

-

-advtrains.ap.t_diagonalcrossing = {

-	regstep=1,

-	variant={

-		["30l45r"]={

-			conns = {{c=1}, {c=9}, {c=6}, {c=14}},

-			desc = "30left-45right diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="60l30l",

-		},

-		["60l30l"]={

-			conns = {{c=3}, {c=11}, {c=1}, {c=9}},

-			desc = "30left-60right diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="60l45r"

-		},

-		["60l45r"]={

-			conns = {{c=3}, {c=11}, {c=6}, {c=14}},

-			desc = "60left-45right diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="60l60r"

-		},

-		["60l60r"]={

-			conns = {{c=3}, {c=11}, {c=5}, {c=13}},

-			desc = "60left-60right diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="60r45l",

-		},

-		--If 60l60r had a mirror image, it would be here, but it's symmetric.

-		-- 60l60r is also equivalent to 30l30r but rotated 90 degrees.

-		["60r45l"]={

-			conns = {{c=5}, {c=13}, {c=2}, {c=10}},

-			desc = "60right-45left diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="60r30r",

-		},

-		["60r30r"]={

-			conns = {{c=5}, {c=13}, {c=7}, {c=15}},

-			desc = "60right-30right diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="30r45l",

-		},

-		["30r45l"]={

-			conns = {{c=7}, {c=15}, {c=2}, {c=10}},

-			desc = "30right-45left diagonal crossing",

-			tpdouble=true,

-			tpsingle=true,

-			trackworker="30l45r",

-		},

-

-	},

-	regtp=true,

-	tpdefault="30l45r",

-	rotation={""},

-	trackworker = {

-		["30l45r"] = "60l30l",

-		["60l30l"] = "60l45r",

-		["60l45r"] = "60l60r",

-		["60l60r"] = "60r45l",

-		["60r45l"] = "60r30r",

-		["60r30r"] = "30r45l",

-		["30r45l"] = "30l45r",

-	}

-}

-

-advtrains.trackpresets = advtrains.ap

-

---definition format: ([] optional)

---[[{

-	nodename_prefix

-	texture_prefix

-	[shared_texture]

-	models_prefix

-	models_suffix (with dot)

-	[shared_model]

-	formats={

-		st,cr,swlst,swlcr,swrst,swrcr,vst1,vst2

-		(each a table with indices 0-3, for if to register a rail with this 'rotation' table entry. nil is assumed as 'all', set {} to not register at all)

-	}

-	common={} change something on common rail appearance

-}

-[18.12.17] Note on new connection system:

-In order to support real rail crossing nodes and finally make the trackplacer respect switches, I changed the connection system.

-There can be a variable number of connections available. These are specified as tuples {c=<connection>, y=<rely>}

-The table "at_conns" consists of {<conn1>, <conn2>...}

-the "at_rail_y" property holds the value that was previously called "railheight"

-Depending on the number of connections:

-2 conns: regular rail

-3 conns: switch:

-	- when train passes in at conn1, will move out of conn2

-	- when train passes in at conn2 or conn3, will move out of conn1

-4 conns: cross (or cross switch, depending on arrangement of conns):

-	- conn1 <> conn2

-	- conn3 <> conn4

-]]

-

-function advtrains.register_tracks(tracktype, def, preset)

-	advtrains.trackplacer.register_tracktype(def.nodename_prefix, preset.tpdefault)

-	if preset.regtp then

-		advtrains.trackplacer.register_track_placer(def.nodename_prefix, def.texture_prefix, def.description, def)			

-	end

-	if preset.regsp then

-		advtrains.slope.register_placer(def, preset)			

-	end

-	for suffix, var 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 img_suffix = suffix..rotation

-				local ndef = advtrains.merge_tables({

-					description=def.description.."("..(var.desc or "any")..rotation..")",

-					drawtype = "mesh",

-					paramtype="light",

-					paramtype2="facedir",

-					walkable = false,

-					selection_box = {

-						type = "fixed",

-						fixed = {-1/2, -1/2, -1/2, 1/2, -1/2+1/16, 1/2},

-					},

-					

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

-					tiles = {def.shared_texture or (def.texture_prefix.."_"..img_suffix..".png"), def.second_texture},

-					

-					groups = {

-						attached_node=1,

-						advtrains_track=1,

-						["advtrains_track_"..tracktype]=1,

-						save_in_at_nodedb=1,

-						dig_immediate=2,

-						not_in_creative_inventory=1,

-						not_blocking_trains=1,

-					},

-						

-					can_dig = advtrains.can_dig_or_modify_track,

-					after_dig_node=function(pos)

-						advtrains.ndb.update(pos)

-					end,

-					after_place_node=function(pos)

-						advtrains.ndb.update(pos)

-					end,

-					at_nnpref = def.nodename_prefix,

-					at_suffix = suffix,

-					at_rotation = rotation,

-					at_rail_y = var.rail_y

-				}, def.common or {})

-				

-				if preset.regtp then

-					ndef.drop = def.nodename_prefix.."_placer"

-				end

-				if preset.regsp and var.slope then

-					ndef.drop = def.nodename_prefix.."_slopeplacer"

-				end

-				

-				--connections

-				ndef.at_conns = advtrains.rotate_conn_by(var.conns, (rotid-1)*preset.regstep)

-				

-				local ndef_avt_table

-				

-				if var.switchalt and var.switchst then

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

-						newstate = newstate or var.switchalt -- support for 3 (or more) state switches

-						-- this code is only called from the internal setstate function, which

-						-- ensures that it is safe to switch the turnout

-						if newstate~=var.switchst then

-							advtrains.ndb.swap_node(pos, {name=def.nodename_prefix.."_"..(var.switchprefix or "")..newstate..rotation, param2=node.param2})

-							advtrains.invalidate_all_paths(pos)

-						end

-					end

-					ndef.on_rightclick = function(pos, node, player)

-						if advtrains.check_turnout_signal_protection(pos, player:get_player_name()) then

-							advtrains.setstate(pos, newstate, node)

-							advtrains.log("Switch", player:get_player_name(), pos)

-						end

-					end

-					if var.switchmc then

-						ndef.mesecons = {effector = {

-							["action_"..var.switchmc] = function(pos, node) 

-								advtrains.setstate(pos, nil, node)

-							end,

-							rules=advtrains.meseconrules

-						}}

-					end

-					ndef_avt_table = {

-						getstate = var.switchst,

-						setstate = switchfunc,

-					}

-				end

-				

-				local adef={}

-				if def.get_additional_definiton then

-					adef=def.get_additional_definiton(def, preset, suffix, rotation)

-				end

-				ndef = advtrains.merge_tables(ndef, adef)

-				

-				-- insert getstate/setstate functions after merging the additional definitions

-				if ndef_avt_table then

-					ndef.advtrains = advtrains.merge_tables(ndef.advtrains or {}, ndef_avt_table)

-				end

-

-				minetest.register_node(":"..def.nodename_prefix.."_"..suffix..rotation, ndef)

-				--trackplacer

-				if preset.regtp then

-					local tpconns = {conn1=ndef.at_conns[1].c, conn2=ndef.at_conns[2].c}

-					if var.tpdouble then

-						advtrains.trackplacer.add_double_conn(def.nodename_prefix, suffix, rotation, tpconns)

-					end

-					if var.tpsingle then

-						advtrains.trackplacer.add_single_conn(def.nodename_prefix, suffix, rotation, tpconns)

-					end

-				end

-				advtrains.trackplacer.add_worked(def.nodename_prefix, suffix, rotation, var.trackworker)

-			end

-		end

-	end

-	advtrains.all_tracktypes[tracktype]=true

-end

-

-function advtrains.is_track_and_drives_on(nodename, drives_on_p)

-	local drives_on = drives_on_p

-	if not drives_on then drives_on = advtrains.all_tracktypes end

-	local hasentry = false

-	for _,_ in pairs(drives_on) do

-		hasentry=true

-	end

-	if not hasentry then drives_on = advtrains.all_tracktypes end

-	

-	if not minetest.registered_nodes[nodename] then

-		return false

-	end

-	local nodedef=minetest.registered_nodes[nodename]

-	for k,v in pairs(drives_on) do

-		if nodedef.groups["advtrains_track_"..k] then

-			return true

-		end

-	end

-	return false

-end

-

-function advtrains.get_track_connections(name, param2)

-	local nodedef=minetest.registered_nodes[name]

-	if not nodedef then atprint(" get_track_connections couldn't find nodedef for nodename "..(name or "nil")) return nil end

-	local noderot=param2

-	if not param2 then noderot=0 end

-	if noderot > 3 then atprint(" get_track_connections: rail has invaild param2 of "..noderot) noderot=0 end

-	

-	local tracktype

-	for k,_ in pairs(nodedef.groups) do

-		local tt=string.match(k, "^advtrains_track_(.+)$")

-		if tt then

-			tracktype=tt

-		end

-	end

-	return advtrains.rotate_conn_by(nodedef.at_conns, noderot*AT_CMAX/4), (nodedef.at_rail_y or 0), tracktype

-end

-

--- Function called when a track is about to be dug or modified by the trackworker

--- Returns either true (ok) or false,"translated string describing reason why it isn't allowed"

-function advtrains.can_dig_or_modify_track(pos)

-	if advtrains.get_train_at_pos(pos) then

-		return false, attrans("Position is occupied by a train.")

-	end

-	-- interlocking: tcb, signal IP a.s.o.

-	if advtrains.interlocking then

-		-- TCB?

-		if advtrains.interlocking.db.get_tcb(pos) then

-			return false, attrans("There's a Track Circuit Break here.")

-		end

-		-- signal ip?

-		if advtrains.interlocking.db.is_ip_at(pos) then

-			return false, attrans("There's a Signal Influence Point here.")

-		end

-	end

-	return true

-end

-

--- slope placer. Defined in register_tracks.

---crafted with rail and gravel

-local sl={}

-function sl.register_placer(def, preset)

-	minetest.register_craftitem(":"..def.nodename_prefix.."_slopeplacer",{

-		description = attrans("@1 Slope", def.description),

-		inventory_image = def.texture_prefix.."_slopeplacer.png",

-		wield_image = def.texture_prefix.."_slopeplacer.png",

-		groups={},

-		on_place = sl.create_slopeplacer_on_place(def, preset)

-	})

-end

---(itemstack, placer, pointed_thing)

-function sl.create_slopeplacer_on_place(def, preset)

-	return function(istack, player, pt)

-		if not pt.type=="node" then 

-			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: not pointing at node"))

-			return istack 

-		end

-		local pos=pt.above

-		if not pos then 

-			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: not pointing at node"))

-			return istack

-		end

-		local node=minetest.get_node(pos)

-		if not minetest.registered_nodes[node.name] or not minetest.registered_nodes[node.name].buildable_to then

-			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: space occupied!"))

-			return istack

-		end

-		if not advtrains.check_track_protection(pos, player:get_player_name()) then 

-			minetest.record_protection_violation(pos, player:get_player_name())

-			return istack

-		end

-		--determine player orientation (only horizontal component)

-		--get_look_horizontal may not be available

-		local yaw=player.get_look_horizontal and player:get_look_horizontal() or (player:get_look_yaw() - math.pi/2)

-		

-		--rounding unit vectors is a nice way for selecting 1 of 8 directions since sin(30°) is 0.5.

-		dirvec={x=math.floor(math.sin(-yaw)+0.5), y=0, z=math.floor(math.cos(-yaw)+0.5)}

-		--translate to direction to look up inside the preset table

-		local param2, rot45=({

-			[-1]={

-				[-1]=2,

-				[0]=3,

-				[1]=3,

-				},

-			[0]={

-				[-1]=2,

-				[1]=0,

-				},

-			[1]={

-				[-1]=1,

-				[0]=1,

-				[1]=0,

-				},

-		})[dirvec.x][dirvec.z], dirvec.x~=0 and dirvec.z~=0

-		local lookup=preset.slopeplacer

-		if rot45 then lookup=preset.slopeplacer_45 end

-		

-		--go unitvector forward and look how far the next node is

-		local step=1

-		while step<=lookup.max do

-			local node=minetest.get_node(vector.add(pos, dirvec))

-			--next node solid?

-			if not minetest.registered_nodes[node.name] or not minetest.registered_nodes[node.name].buildable_to or advtrains.is_protected(pos, player:get_player_name()) then 

-				--do slopes of this distance exist?

-				if lookup[step] then

-					if minetest.settings:get_bool("creative_mode") or istack:get_count()>=step then

-						--start placing

-						local placenodes=lookup[step]

-						while step>0 do

-							minetest.set_node(pos, {name=def.nodename_prefix.."_"..placenodes[step], param2=param2})

-							if not minetest.settings:get_bool("creative_mode") then

-								istack:take_item()

-							end

-							step=step-1

-							pos=vector.subtract(pos, dirvec)

-						end

-					else

-						minetest.chat_send_player(player:get_player_name(), attrans("Can't place: Not enough slope items left (@1 required)", step))

-					end

-				else

-					minetest.chat_send_player(player:get_player_name(), attrans("Can't place: There's no slope of length @1",step))

-				end

-				return istack

-			end

-			step=step+1

-			pos=vector.add(pos, dirvec)

-		end

-		minetest.chat_send_player(player:get_player_name(), attrans("Can't place: no supporting node at upper end."))

-		return itemstack

-	end

-end

-

-advtrains.slope=sl

-

---END code, BEGIN definition

---definition format: ([] optional)

---[[{

-	nodename_prefix

-	texture_prefix

-	[shared_texture]

-	models_prefix

-	models_suffix (with dot)

-	[shared_model]

-	formats={

-		st,cr,swlst,swlcr,swrst,swrcr,vst1,vst2

-		(each a table with indices 0-3, for if to register a rail with this 'rotation' table entry. nil is assumed as 'all', set {} to not register at all)

-	}

-	common={} change something on common rail appearance

-}]]

-

-

-

-

-

-

-

-

-

+			desc = "3-way turnout (right)",
+			switchalt = "l",
+			switchst="r",
+			switchprefix = "",
+		}
+	},
+	regtp=true,
+	tpdefault="l",
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_30deg_slope={
+	regstep=1,
+	variant={
+		vst1={conns = conns(8,0,0,0.5), rail_y = 0.25, desc = "steep uphill 1/2", slope=true},
+		vst2={conns = conns(8,0,0.5,1), rail_y = 0.75, desc = "steep uphill 2/2", slope=true},
+		vst31={conns = conns(8,0,0,0.33), rail_y = 0.16, desc = "uphill 1/3", slope=true},
+		vst32={conns = conns(8,0,0.33,0.66), rail_y = 0.5, desc = "uphill 2/3", slope=true},
+		vst33={conns = conns(8,0,0.66,1), rail_y = 0.83, desc = "uphill 3/3", slope=true},
+	},
+	regsp=true,
+	slopeplacer={
+		[2]={"vst1", "vst2"},
+		[3]={"vst31", "vst32", "vst33"},
+		max=3,--highest entry
+	},
+	slopeplacer_45={
+		[2]={"vst1_45", "vst2_45"},
+		max=2,
+	},
+	rotation={"", "_30", "_45", "_60"},
+	trackworker={},
+	increativeinv={},
+}
+advtrains.ap.t_30deg_straightonly={
+	regstep=1,
+	variant={
+		st={
+			conns = conns(0,8),
+			desc = "straight",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "st",
+		},
+	},
+	regtp=true,
+	tpdefault="st",
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_30deg_straightonly_noplacer={
+	regstep=1,
+	variant={
+		st={
+			conns = conns(0,8),
+			desc = "straight",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "st",
+		},
+	},
+	tpdefault="st",
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_45deg={
+	regstep=2,
+	variant={
+		st={
+			conns = conns(0,8),
+			desc = "straight",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "cr",
+		},
+		cr={
+			conns = conns(0,6),
+			desc = "curve",
+			tpdouble = true,
+			trackworker = "swlst",
+		},
+		swlst={
+			conns = conns3(0,8,6),
+			desc = "left switch (straight)",
+			trackworker = "swrst",
+			switchalt = "cr",
+			switchmc = "on",
+			switchst = "st",
+		},
+		swlcr={
+			conns = conns3(0,6,8),
+			desc = "left switch (curve)",
+			trackworker = "swrcr",
+			switchalt = "st",
+			switchmc = "off",
+			switchst = "cr",
+		},
+		swrst={
+			conns = conns3(0,8,10),
+			desc = "right switch (straight)",
+			trackworker = "st",
+			switchalt = "cr",
+			switchmc = "on",
+			switchst = "st",
+		},
+		swrcr={
+			conns = conns3(0,10,8),
+			desc = "right switch (curve)",
+			trackworker = "st",
+			switchalt = "st",
+			switchmc = "off",
+			switchst = "cr",
+		},
+	},
+	regtp=true,
+	tpdefault="st",
+	trackworker={
+		["swrcr"]="st",
+		["swrst"]="st",
+		["cr"]="swlst",
+		["swlcr"]="swrcr",
+		["swlst"]="swrst",
+	},
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_perpcrossing={
+	regstep = 1,
+	variant={
+		st={
+			conns = { {c=0}, {c=8}, {c=4}, {c=12} },
+			desc = "perpendicular crossing",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "st",
+		},
+	},
+	regtp=true,
+	tpdefault="st",
+	rotation={"", "_30", "_45", "_60"},
+}
+advtrains.ap.t_90plusx_crossing={
+	regstep = 1,
+	variant={
+		["30l"]={
+			conns = { {c=0}, {c=8}, {c=1}, {c=9} },
+			desc = "30/90 degree crossing (left)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "45l"
+		},
+		["45l"]={
+			conns = { {c=0}, {c=8}, {c=2}, {c=10} },
+			desc = "45/90 degree crossing (left)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "60l",
+		},
+		["60l"]={
+			conns = { {c=0}, {c=8}, {c=3}, {c=11}},
+			desc = "60/90 degree crossing (left)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "60r",
+		},
+		["60r"]={
+			conns = { {c=0}, {c=8}, {c=7}, {c=15} },
+			desc = "60/90 degree crossing (right)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "45r"
+		},
+		["45r"]={
+			conns = { {c=0}, {c=8}, {c=6}, {c=14} },
+			desc = "45/90 degree crossing (right)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "30r",
+		},
+		["30r"]={
+			conns = { {c=0}, {c=8}, {c=7}, {c=15}},
+			desc = "30/90 degree crossing (right)",
+			tpdouble = true,
+			tpsingle = true,
+			trackworker = "30l",
+		},
+	},
+	regtp=true,
+	tpdefault="30l",
+	rotation={""},
+	trackworker = {
+		["30l"] = "45l",
+		["45l"] = "60l",
+		["60l"] = "60r",
+		["60r"] = "45r",
+		["45r"] = "30r",
+		["30r"] = "30l",
+	}
+}
+
+advtrains.ap.t_diagonalcrossing = {
+	regstep=1,
+	variant={
+		["30l45r"]={
+			conns = {{c=1}, {c=9}, {c=6}, {c=14}},
+			desc = "30left-45right diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="60l30l",
+		},
+		["60l30l"]={
+			conns = {{c=3}, {c=11}, {c=1}, {c=9}},
+			desc = "30left-60right diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="60l45r"
+		},
+		["60l45r"]={
+			conns = {{c=3}, {c=11}, {c=6}, {c=14}},
+			desc = "60left-45right diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="60l60r"
+		},
+		["60l60r"]={
+			conns = {{c=3}, {c=11}, {c=5}, {c=13}},
+			desc = "60left-60right diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="60r45l",
+		},
+		--If 60l60r had a mirror image, it would be here, but it's symmetric.
+		-- 60l60r is also equivalent to 30l30r but rotated 90 degrees.
+		["60r45l"]={
+			conns = {{c=5}, {c=13}, {c=2}, {c=10}},
+			desc = "60right-45left diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="60r30r",
+		},
+		["60r30r"]={
+			conns = {{c=5}, {c=13}, {c=7}, {c=15}},
+			desc = "60right-30right diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="30r45l",
+		},
+		["30r45l"]={
+			conns = {{c=7}, {c=15}, {c=2}, {c=10}},
+			desc = "30right-45left diagonal crossing",
+			tpdouble=true,
+			tpsingle=true,
+			trackworker="30l45r",
+		},
+
+	},
+	regtp=true,
+	tpdefault="30l45r",
+	rotation={""},
+	trackworker = {
+		["30l45r"] = "60l30l",
+		["60l30l"] = "60l45r",
+		["60l45r"] = "60l60r",
+		["60l60r"] = "60r45l",
+		["60r45l"] = "60r30r",
+		["60r30r"] = "30r45l",
+		["30r45l"] = "30l45r",
+	}
+}
+
+advtrains.trackpresets = advtrains.ap
+
+--definition format: ([] optional)
+--[[{
+	nodename_prefix
+	texture_prefix
+	[shared_texture]
+	models_prefix
+	models_suffix (with dot)
+	[shared_model]
+	formats={
+		st,cr,swlst,swlcr,swrst,swrcr,vst1,vst2
+		(each a table with indices 0-3, for if to register a rail with this 'rotation' table entry. nil is assumed as 'all', set {} to not register at all)
+	}
+	common={} change something on common rail appearance
+}
+[18.12.17] Note on new connection system:
+In order to support real rail crossing nodes and finally make the trackplacer respect switches, I changed the connection system.
+There can be a variable number of connections available. These are specified as tuples {c=<connection>, y=<rely>}
+The table "at_conns" consists of {<conn1>, <conn2>...}
+the "at_rail_y" property holds the value that was previously called "railheight"
+Depending on the number of connections:
+2 conns: regular rail
+3 conns: switch:
+	- when train passes in at conn1, will move out of conn2
+	- when train passes in at conn2 or conn3, will move out of conn1
+4 conns: cross (or cross switch, depending on arrangement of conns):
+	- conn1 <> conn2
+	- conn3 <> conn4
+]]
+
+function advtrains.register_tracks(tracktype, def, preset)
+	advtrains.trackplacer.register_tracktype(def.nodename_prefix, preset.tpdefault)
+	if preset.regtp then
+		advtrains.trackplacer.register_track_placer(def.nodename_prefix, def.texture_prefix, def.description, def)			
+	end
+	if preset.regsp then
+		advtrains.slope.register_placer(def, preset)			
+	end
+	for suffix, var 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 img_suffix = suffix..rotation
+				local ndef = advtrains.merge_tables({
+					description=def.description.."("..(var.desc or "any")..rotation..")",
+					drawtype = "mesh",
+					paramtype="light",
+					paramtype2="facedir",
+					walkable = false,
+					selection_box = {
+						type = "fixed",
+						fixed = {-1/2, -1/2, -1/2, 1/2, -1/2+1/16, 1/2},
+					},
+					
+					mesh = def.shared_model or (def.models_prefix.."_"..img_suffix..def.models_suffix),
+					tiles = {def.shared_texture or (def.texture_prefix.."_"..img_suffix..".png"), def.second_texture},
+					
+					groups = {
+						attached_node=1,
+						advtrains_track=1,
+						["advtrains_track_"..tracktype]=1,
+						save_in_at_nodedb=1,
+						dig_immediate=2,
+						not_in_creative_inventory=1,
+						not_blocking_trains=1,
+					},
+						
+					can_dig = advtrains.can_dig_or_modify_track,
+					after_dig_node=function(pos)
+						advtrains.ndb.update(pos)
+					end,
+					after_place_node=function(pos)
+						advtrains.ndb.update(pos)
+					end,
+					at_nnpref = def.nodename_prefix,
+					at_suffix = suffix,
+					at_rotation = rotation,
+					at_rail_y = var.rail_y
+				}, def.common or {})
+				
+				if preset.regtp then
+					ndef.drop = def.nodename_prefix.."_placer"
+				end
+				if preset.regsp and var.slope then
+					ndef.drop = def.nodename_prefix.."_slopeplacer"
+				end
+				
+				--connections
+				ndef.at_conns = advtrains.rotate_conn_by(var.conns, (rotid-1)*preset.regstep)
+				
+				local ndef_avt_table
+				
+				if var.switchalt and var.switchst then
+					local switchfunc=function(pos, node, newstate)
+						newstate = newstate or var.switchalt -- support for 3 (or more) state switches
+						-- this code is only called from the internal setstate function, which
+						-- ensures that it is safe to switch the turnout
+						if newstate~=var.switchst then
+							advtrains.ndb.swap_node(pos, {name=def.nodename_prefix.."_"..(var.switchprefix or "")..newstate..rotation, param2=node.param2})
+							advtrains.invalidate_all_paths(pos)
+						end
+					end
+					ndef.on_rightclick = function(pos, node, player)
+						if advtrains.check_turnout_signal_protection(pos, player:get_player_name()) then
+							advtrains.setstate(pos, newstate, node)
+							advtrains.log("Switch", player:get_player_name(), pos)
+						end
+					end
+					if var.switchmc then
+						ndef.mesecons = {effector = {
+							["action_"..var.switchmc] = function(pos, node) 
+								advtrains.setstate(pos, nil, node)
+							end,
+							rules=advtrains.meseconrules
+						}}
+					end
+					ndef_avt_table = {
+						getstate = var.switchst,
+						setstate = switchfunc,
+					}
+				end
+				
+				local adef={}
+				if def.get_additional_definiton then
+					adef=def.get_additional_definiton(def, preset, suffix, rotation)
+				end
+				ndef = advtrains.merge_tables(ndef, adef)
+				
+				-- insert getstate/setstate functions after merging the additional definitions
+				if ndef_avt_table then
+					ndef.advtrains = advtrains.merge_tables(ndef.advtrains or {}, ndef_avt_table)
+				end
+
+				minetest.register_node(":"..def.nodename_prefix.."_"..suffix..rotation, ndef)
+				--trackplacer
+				if preset.regtp then
+					local tpconns = {conn1=ndef.at_conns[1].c, conn2=ndef.at_conns[2].c}
+					if var.tpdouble then
+						advtrains.trackplacer.add_double_conn(def.nodename_prefix, suffix, rotation, tpconns)
+					end
+					if var.tpsingle then
+						advtrains.trackplacer.add_single_conn(def.nodename_prefix, suffix, rotation, tpconns)
+					end
+				end
+				advtrains.trackplacer.add_worked(def.nodename_prefix, suffix, rotation, var.trackworker)
+			end
+		end
+	end
+	advtrains.all_tracktypes[tracktype]=true
+end
+
+function advtrains.is_track_and_drives_on(nodename, drives_on_p)
+	local drives_on = drives_on_p
+	if not drives_on then drives_on = advtrains.all_tracktypes end
+	local hasentry = false
+	for _,_ in pairs(drives_on) do
+		hasentry=true
+	end
+	if not hasentry then drives_on = advtrains.all_tracktypes end
+	
+	if not minetest.registered_nodes[nodename] then
+		return false
+	end
+	local nodedef=minetest.registered_nodes[nodename]
+	for k,v in pairs(drives_on) do
+		if nodedef.groups["advtrains_track_"..k] then
+			return true
+		end
+	end
+	return false
+end
+
+function advtrains.get_track_connections(name, param2)
+	local nodedef=minetest.registered_nodes[name]
+	if not nodedef then atprint(" get_track_connections couldn't find nodedef for nodename "..(name or "nil")) return nil end
+	local noderot=param2
+	if not param2 then noderot=0 end
+	if noderot > 3 then atprint(" get_track_connections: rail has invaild param2 of "..noderot) noderot=0 end
+	
+	local tracktype
+	for k,_ in pairs(nodedef.groups) do
+		local tt=string.match(k, "^advtrains_track_(.+)$")
+		if tt then
+			tracktype=tt
+		end
+	end
+	return advtrains.rotate_conn_by(nodedef.at_conns, noderot*AT_CMAX/4), (nodedef.at_rail_y or 0), tracktype
+end
+
+-- Function called when a track is about to be dug or modified by the trackworker
+-- Returns either true (ok) or false,"translated string describing reason why it isn't allowed"
+function advtrains.can_dig_or_modify_track(pos)
+	if advtrains.get_train_at_pos(pos) then
+		return false, attrans("Position is occupied by a train.")
+	end
+	-- interlocking: tcb, signal IP a.s.o.
+	if advtrains.interlocking then
+		-- TCB?
+		if advtrains.interlocking.db.get_tcb(pos) then
+			return false, attrans("There's a Track Circuit Break here.")
+		end
+		-- signal ip?
+		if advtrains.interlocking.db.is_ip_at(pos) then
+			return false, attrans("There's a Signal Influence Point here.")
+		end
+	end
+	return true
+end
+
+-- slope placer. Defined in register_tracks.
+--crafted with rail and gravel
+local sl={}
+function sl.register_placer(def, preset)
+	minetest.register_craftitem(":"..def.nodename_prefix.."_slopeplacer",{
+		description = attrans("@1 Slope", def.description),
+		inventory_image = def.texture_prefix.."_slopeplacer.png",
+		wield_image = def.texture_prefix.."_slopeplacer.png",
+		groups={},
+		on_place = sl.create_slopeplacer_on_place(def, preset)
+	})
+end
+--(itemstack, placer, pointed_thing)
+function sl.create_slopeplacer_on_place(def, preset)
+	return function(istack, player, pt)
+		if not pt.type=="node" then 
+			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: not pointing at node"))
+			return istack 
+		end
+		local pos=pt.above
+		if not pos then 
+			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: not pointing at node"))
+			return istack
+		end
+		local node=minetest.get_node(pos)
+		if not minetest.registered_nodes[node.name] or not minetest.registered_nodes[node.name].buildable_to then
+			minetest.chat_send_player(player:get_player_name(), attrans("Can't place: space occupied!"))
+			return istack
+		end
+		if not advtrains.check_track_protection(pos, player:get_player_name()) then 
+			minetest.record_protection_violation(pos, player:get_player_name())
+			return istack
+		end
+		--determine player orientation (only horizontal component)
+		--get_look_horizontal may not be available
+		local yaw=player.get_look_horizontal and player:get_look_horizontal() or (player:get_look_yaw() - math.pi/2)
+		
+		--rounding unit vectors is a nice way for selecting 1 of 8 directions since sin(30°) is 0.5.
+		dirvec={x=math.floor(math.sin(-yaw)+0.5), y=0, z=math.floor(math.cos(-yaw)+0.5)}
+		--translate to direction to look up inside the preset table
+		local param2, rot45=({
+			[-1]={
+				[-1]=2,
+				[0]=3,
+				[1]=3,
+				},
+			[0]={
+				[-1]=2,
+				[1]=0,
+				},
+			[1]={
+				[-1]=1,
+				[0]=1,
+				[1]=0,
+				},
+		})[dirvec.x][dirvec.z], dirvec.x~=0 and dirvec.z~=0
+		local lookup=preset.slopeplacer
+		if rot45 then lookup=preset.slopeplacer_45 end
+		
+		--go unitvector forward and look how far the next node is
+		local step=1
+		while step<=lookup.max do
+			local node=minetest.get_node(vector.add(pos, dirvec))
+			--next node solid?
+			if not minetest.registered_nodes[node.name] or not minetest.registered_nodes[node.name].buildable_to or advtrains.is_protected(pos, player:get_player_name()) then 
+				--do slopes of this distance exist?
+				if lookup[step] then
+					if minetest.settings:get_bool("creative_mode") or istack:get_count()>=step then
+						--start placing
+						local placenodes=lookup[step]
+						while step>0 do
+							minetest.set_node(pos, {name=def.nodename_prefix.."_"..placenodes[step], param2=param2})
+							if not minetest.settings:get_bool("creative_mode") then
+								istack:take_item()
+							end
+							step=step-1
+							pos=vector.subtract(pos, dirvec)
+						end
+					else
+						minetest.chat_send_player(player:get_player_name(), attrans("Can't place: Not enough slope items left (@1 required)", step))
+					end
+				else
+					minetest.chat_send_player(player:get_player_name(), attrans("Can't place: There's no slope of length @1",step))
+				end
+				return istack
+			end
+			step=step+1
+			pos=vector.add(pos, dirvec)
+		end
+		minetest.chat_send_player(player:get_player_name(), attrans("Can't place: no supporting node at upper end."))
+		return itemstack
+	end
+end
+
+advtrains.slope=sl
+
+--END code, BEGIN definition
+--definition format: ([] optional)
+--[[{
+	nodename_prefix
+	texture_prefix
+	[shared_texture]
+	models_prefix
+	models_suffix (with dot)
+	[shared_model]
+	formats={
+		st,cr,swlst,swlcr,swrst,swrcr,vst1,vst2
+		(each a table with indices 0-3, for if to register a rail with this 'rotation' table entry. nil is assumed as 'all', set {} to not register at all)
+	}
+	common={} change something on common rail appearance
+}]]
+
+
+
+
+
+
+
+
+
diff --git a/advtrains/wagons.lua b/advtrains/wagons.lua
index 90615a5..6b59293 100644
--- a/advtrains/wagons.lua
+++ b/advtrains/wagons.lua
@@ -1,1437 +1,1437 @@
--- wagon.lua

--- Holds all logic related to wagons

--- From now on, wagons are, just like trains, just entries in a table

--- All data that is static is stored in the entity prototype (self).

---   A copy of the entity prototype is always available inside wagon_prototypes

--- All dynamic data is stored in the (new) wagons table

--- An entity is ONLY spawned by update_trainpart_properties when it finds it useful.

--- Only data that are only important to the entity itself are stored in the luaentity

-

--- TP delay when getting off wagon

-local GETOFF_TP_DELAY = 0.5

-

-advtrains.wagons = {}

-advtrains.wagon_prototypes = {}

-advtrains.wagon_objects = {}

-

-local unload_wgn_range = advtrains.wagon_load_range + 32

-

-local setting_show_ids = minetest.settings:get_bool("advtrains_show_ids")

-

---

-function advtrains.create_wagon(wtype, owner)

-	local new_id=advtrains.random_id()

-	while advtrains.wagons[new_id] do new_id=advtrains.random_id() end

-	local wgn = {}

-	wgn.type = wtype

-	wgn.seatp = {}

-	wgn.owner = owner

-	wgn.id = new_id

-	---wgn.train_id = train_id   --- will get this via update_trainpart_properties

-	advtrains.wagons[new_id] = wgn

-	--atdebug("Created new wagon:",wgn)

-	return new_id

-end

-

-local function make_inv_name(uid)

-	return "detached:advtrains_wgn_"..uid

-end

-

-

-local wagon={

-	collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},

-	--physical = true,

-	visual = "mesh",

-	mesh = "wagon.b3d",

-	visual_size = {x=1, y=1},

-	textures = {"black.png"},

-	is_wagon=true,

-	wagon_span=1,--how many index units of space does this wagon consume

-	wagon_width=3, -- Wagon width in meters

-	has_inventory=false,

-	static_save=false,

-}

-

-

-function wagon:train()

-	local data = advtrains.wagons[self.id]

-	return advtrains.trains[data.train_id]

-end

-

-

-function wagon:on_activate(sd_uid, dtime_s)

-	if sd_uid~="" then

-		--destroy when loaded from static block.

-		self.object:remove()

-		return

-	end

-	self.object:set_armor_groups({immortal=1})

-end

-

-local function invcallback(id, pname, rtallow, rtfail)

-	local data = advtrains.wagons[id]

-	if data and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-		return rtallow

-	end

-	return rtfail

-end

-

-function wagon:set_id(wid)

-	self.id = wid

-	self.initialized = true

-	

-	local data = advtrains.wagons[self.id]

-	advtrains.wagon_objects[self.id] = self.object

-	

-	--atdebug("Created wagon entity:",self.name," w_id",wid," t_id",data.train_id)

-	

-	if self.has_inventory then

-		--to be used later

-		local inv=minetest.get_inventory({type="detached", name="advtrains_wgn_"..self.id})

-		-- create inventory, if not yet created

-		if not inv then	

-			inv=minetest.create_detached_inventory("advtrains_wgn_"..self.id, {

-				allow_move = function(inv, from_list, from_index, to_list, to_index, count, player)

-					return invcallback(wid, player:get_player_name(), count, 0)

-				end,

-				allow_put = function(inv, listname, index, stack, player)

-					return invcallback(wid, player:get_player_name(), stack:get_count(), 0)

-				end,

-				allow_take = function(inv, listname, index, stack, player)

-					return invcallback(wid, player:get_player_name(), stack:get_count(), 0)

-				end

-			})

-			if data.ser_inv then

-				advtrains.deserialize_inventory(data.ser_inv, inv)

-			end

-			if self.inventory_list_sizes then

-				for lst, siz in pairs(self.inventory_list_sizes) do

-					inv:set_size(lst, siz)

-				end

-			end

-		end

-	end

-	self.door_anim_timer=0

-	self.door_state=0

-	

-	minetest.after(0.2, function() self:reattach_all() end)

-	

-	

-	

-	if self.set_textures then

-		self:set_textures(data)

-	end

-	

-	if self.custom_on_activate then

-		self:custom_on_activate()

-	end

-end

-

-function wagon:get_staticdata()

-	return "STATIC"

-end

-

-function wagon:ensure_init()

-			-- Note: A wagon entity won't exist when there's no train, because the train is

-			-- the thing that actually creates the entity

-			-- Train not being set just means that this will happen as soon as the train calls update_trainpart_properties.

-	if self.initialized and self.id then

-		local data = advtrains.wagons[self.id]

-		if data and data.train_id and self:train() then

-			if self.noninitticks then self.noninitticks=nil end

-			return true

-		end

-	end

-	if not self.noninitticks then

-		atwarn("wagon",self.id,"uninitialized init=",self.initialized)

-		self.noninitticks=0

-	end

-	self.noninitticks=self.noninitticks+1

-	if self.noninitticks>20 then

-		atwarn("wagon",self.id,"uninitialized, removing")

-		self:destroy()

-	else

-		self.object:setvelocity({x=0,y=0,z=0})

-	end

-	return false

-end

-

-function wagon:train()

-	local data = advtrains.wagons[self.id]

-	return advtrains.trains[data.train_id]

-end

-

--- Remove the wagon

-function wagon:on_punch(puncher, time_from_last_punch, tool_capabilities, direction)

-	return advtrains.pcall(function()

-		if not self:ensure_init() then return end

-		

-		local data = advtrains.wagons[self.id]

-	

-		if not puncher or not puncher:is_player() then

-			return

-		end

-		if data.owner and puncher:get_player_name()~=data.owner and (not minetest.check_player_privs(puncher, {train_admin = true })) then

-		   minetest.chat_send_player(puncher:get_player_name(), attrans("This wagon is owned by @1, you can't destroy it.", data.owner));

-		   return

-		end

-		

-		if self.custom_may_destroy then

-			if not self.custom_may_destroy(self, puncher, time_from_last_punch, tool_capabilities, direction) then

-				return

-			end

-		end

-		local itemstack = puncher:get_wielded_item()

-		-- WARNING: This part of the API is guaranteed to change! DO NOT USE!

-		if self.set_livery and itemstack:get_name() == "bike:painter" then

-			self:set_livery(puncher, itemstack, data)

-			return

-		end

-		-- check whether wagon has an inventory. Is is empty?

-		if self.has_inventory then

-			local inv=minetest.get_inventory({type="detached", name="advtrains_wgn_"..self.id})

-			if not inv then -- inventory is not initialized when wagon was never loaded - should never happen

-				atwarn("Destroying wagon with inventory, but inventory is not found? Shouldn't happen!")

-				return

-			end

-			for listname, _ in pairs(inv:get_lists()) do

-				if not inv:is_empty(listname) then

-					minetest.chat_send_player(puncher:get_player_name(), attrans("The wagon's inventory is not empty!"));

-					return

-				end

-			end

-		end

-		

-		if #(self:train().trainparts)>1 then

-		   minetest.chat_send_player(puncher:get_player_name(), attrans("Wagon needs to be decoupled from other wagons in order to destroy it."));

-		   return

-		end

-

-		local pc=puncher:get_player_control()

-		if not pc.sneak then

-			minetest.chat_send_player(puncher:get_player_name(), attrans("Warning: If you destroy this wagon, you only get some steel back! If you are sure, hold Sneak and left-click the wagon."))

-			return

-		end

-		

-		

-		if not self:destroy() then return end

-

-		local inv = puncher:get_inventory()

-		for _,item in ipairs(self.drops or {self.name}) do

-			inv:add_item("main", item)

-		end

-	end)

-end

-function wagon:destroy()

-	--some rules:

-	-- you get only some items back

-	-- single left-click shows warning

-	-- shift leftclick destroys

-	-- not when a driver is inside

-	if self.id then

-		local data = advtrains.wagons[self.id]

-		if not data then

-			atwarn("wagon:destroy(): data is not set!")

-			return

-		end

-		

-		if self.custom_on_destroy then

-			self.custom_on_destroy(self)

-		end

-		

-		for seat,_ in pairs(data.seatp) do

-			self:get_off(seat)

-		end

-		

-		if data.train_id and self:train() then

-			advtrains.remove_train(data.train_id)

-			advtrains.wagons[self.id]=nil

-			if self.discouple then self.discouple.object:remove() end--will have no effect on unloaded objects

-		end

-	end

-	--atdebug("[wagon ", self.id, "]: destroying")

-	

-	self.object:remove()

-	return true

-end

-

-function wagon:on_step(dtime)

-	return advtrains.pcall(function()

-		if not self:ensure_init() then return end

-		

-		local t=os.clock()

-		local pos = self.object:getpos()

-		local data = advtrains.wagons[self.id]

-		

-		if not pos then

-			--atdebug("["..self.id.."][fatal] missing position (object:getpos() returned nil)")

-			return

-		end

-		

-		if not data.seatp then

-			data.seatp={}

-		end

-		if not self.seatpc then

-			self.seatpc={}

-		end

-		

-		local train=self:train()

-

-		--custom on_step function

-		if self.custom_on_step then

-			self:custom_on_step(dtime, data, train)

-		end

-

-		--driver control

-		for seatno, seat in ipairs(self.seats) do

-			local pname=data.seatp[seatno]

-			local driver=pname and minetest.get_player_by_name(pname)

-			local has_driverstand = pname and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist)

-			if self.seat_groups then

-				has_driverstand = has_driverstand and (seat.driving_ctrl_access or self.seat_groups[seat.group].driving_ctrl_access)

-			else

-				has_driverstand = has_driverstand and (seat.driving_ctrl_access)

-			end

-			if has_driverstand and driver then

-				advtrains.update_driver_hud(driver:get_player_name(), self:train(), data.wagon_flipped)

-			elseif driver then

-				--only show the inside text

-				local inside=self:train().text_inside or ""

-				advtrains.set_trainhud(driver:get_player_name(), inside)

-			end

-			if driver and driver:get_player_control_bits()~=self.seatpc[seatno] then

-				local pc=driver:get_player_control()

-				self.seatpc[seatno]=driver:get_player_control_bits()

-				

-				if has_driverstand then

-					--regular driver stand controls

-					advtrains.on_control_change(pc, self:train(), data.wagon_flipped)

-					--bordcom

-					if pc.sneak and pc.jump then

-						self:show_bordcom(data.seatp[seatno])

-					end

-					--sound horn when required

-					if self.horn_sound and pc.aux1 and not pc.sneak and not self.horn_handle then

-						self.horn_handle = minetest.sound_play(self.horn_sound, {

-							object = self.object,

-							gain = 1.0, -- default

-							max_hear_distance = 128, -- default, uses an euclidean metric

-							loop = true,

-						})

-					elseif not pc.aux1 and self.horn_handle then

-						minetest.sound_stop(self.horn_handle)

-						self.horn_handle = nil

-					end

-				else

-					-- If on a passenger seat and doors are open, get off when W or D pressed.

-					local pass = data.seatp[seatno] and minetest.get_player_by_name(data.seatp[seatno])

-					if pass and self:train().door_open~=0 then

-					local pc=pass:get_player_control()

-						if pc.up or pc.down then

-							self:get_off(seatno)

-						end

-					end		      

-				end

-				if pc.aux1 and pc.sneak then

-					self:get_off(seatno)

-				end

-			end

-		end

-		

-		--check infotext

-		local outside=train.text_outside or ""

-		if setting_show_ids then

-			outside = outside .. "\nT:" .. data.train_id .. " W:" .. self.id .. " O:" .. data.owner

-		end

-		

-		

-		--show off-track information in outside text instead of notifying the whole server about this

-		if train.off_track then

-			outside = outside .."\n!!! Train off track !!!"

-		end

-		

-		if self.infotext_cache~=outside  then

-			self.object:set_properties({infotext=outside})

-			self.infotext_cache=outside

-		end

-		

-		local fct=data.wagon_flipped and -1 or 1

-		

-		--door animation

-		if self.doors then

-			if (self.door_anim_timer or 0)<=0 then

-				local dstate = (train.door_open or 0) * fct

-				if dstate ~= self.door_state then

-					local at

-					--meaning of the train.door_open field:

-					-- -1: left doors (rel. to train orientation)

-					--  0: closed

-					--  1: right doors

-					--this code produces the following behavior:

-					-- if changed from 0 to +-1, play open anim. if changed from +-1 to 0, play close.

-					-- if changed from +-1 to -+1, first close and set 0, then it will detect state change again and run open.

-					if self.door_state == 0 then

-						if self.doors.open.sound then minetest.sound_play(self.doors.open.sound, {object = self.object}) end

-						at=self.doors.open[dstate]

-						self.object:set_animation(at.frames, at.speed or 15, at.blend or 0, false)

-						self.door_state = dstate

-					else

-						if self.doors.close.sound then minetest.sound_play(self.doors.close.sound, {object = self.object}) end

-						at=self.doors.close[self.door_state or 1]--in case it has not been set yet

-						self.object:set_animation(at.frames, at.speed or 15, at.blend or 0, false)

-						self.door_state = 0

-					end

-					self.door_anim_timer = at.time

-				end

-			else

-				self.door_anim_timer = (self.door_anim_timer or 0) - dtime

-			end

-		end

-		

-		--for path to be available. if not, skip step

-		if not train.path or train.no_step then

-			self.object:setvelocity({x=0, y=0, z=0})

-			self.object:setacceleration({x=0, y=0, z=0})

-			return

-		end

-		if not data.pos_in_train then

-			return

-		end

-		

-		-- Calculate new position, yaw and direction vector

-		local index = advtrains.path_get_index_by_offset(train, train.index, -data.pos_in_train)

-		local pos, yaw, npos, npos2 = advtrains.path_get_interpolated(train, index)

-		local vdir = vector.normalize(vector.subtract(npos2, npos))

-		

-		--automatic get_on

-		--needs to know index and path

-		if self.door_entry and train.door_open and train.door_open~=0 and train.velocity==0 then

-			--using the mapping created by the trainlogic globalstep

-			for i, ino in ipairs(self.door_entry) do

-				--fct is the flipstate flag from door animation above

-				local aci = advtrains.path_get_index_by_offset(train, index, ino*fct)

-				local ix1, ix2 = advtrains.path_get_adjacent(train, aci)

-				-- the two wanted positions are ix1 and ix2 + (2nd-1st rotated by 90deg)

-				-- (x z) rotated by 90deg is (-z x)  (http://stackoverflow.com/a/4780141)

-				local add = { x = (ix2.z-ix1.z)*train.door_open, y = 0, z = (ix1.x-ix2.x)*train.door_open }

-				local pts1=vector.round(vector.add(ix1, add))

-				local pts2=vector.round(vector.add(ix2, add))

-				if minetest.get_item_group(minetest.get_node(pts1).name, "platform")>0 then

-					local ckpts={

-						pts1,

-						pts2,

-						vector.add(pts1, {x=0, y=1, z=0}),

-						vector.add(pts2, {x=0, y=1, z=0}),

-					}

-					for _,ckpos in ipairs(ckpts) do

-						local cpp=minetest.pos_to_string(ckpos)

-						if advtrains.playersbypts[cpp] then

-							self:on_rightclick(advtrains.playersbypts[cpp])

-						end

-					end

-				end

-			end

-		end

-		

-		--checking for environment collisions(a 3x3 cube around the center)

-		if not train.recently_collided_with_env then

-			local collides=false

-			local exh = self.extent_h or 1

-			local exv = self.extent_v or 2

-			for x=-exh,exh do

-				for y=0,exv do

-					for z=-exh,exh do

-						local node=minetest.get_node_or_nil(vector.add(npos, {x=x, y=y, z=z}))

-						if (advtrains.train_collides(node)) then

-							collides=true

-						end

-					end

-				end

-			end

-			if collides then

-				-- screw collision mercy

-				train.recently_collided_with_env=true

-				train.velocity=0

-				advtrains.atc.train_reset_command(train)

-			end

-		end

-		

-		--DisCouple

-		-- FIX: Need to do this after the yaw calculation

-		if data.pos_in_trainparts and data.pos_in_trainparts>1 then

-			if train.velocity==0 then

-				if not self.discouple or not self.discouple.object:getyaw() then

-					atprint(self.id,"trying to spawn discouple")

-					local dcpl_pos = vector.add(pos, {y=0, x=-math.sin(yaw)*self.wagon_span, z=math.cos(yaw)*self.wagon_span})

-					local object=minetest.add_entity(dcpl_pos, "advtrains:discouple")

-					if object then

-						local le=object:get_luaentity()

-						le.wagon=self

-						--box is hidden when attached, so unuseful.

-						--object:set_attach(self.object, "", {x=0, y=0, z=self.wagon_span*10}, {x=0, y=0, z=0})

-						self.discouple=le

-					end

-				end

-			else

-				if self.discouple and self.discouple.object:getyaw() then

-					self.discouple.object:remove()

-					atprint(self.id," removing discouple")

-				end

-			end

-		end

-		

-		--FIX: use index of the wagon, not of the train.

-		local velocity = train.velocity

-		local acceleration = (train.acceleration or 0)

-		local velocityvec = vector.multiply(vdir, velocity)

-		local accelerationvec = vector.multiply(vdir, acceleration)

-		

-		if data.wagon_flipped then

-			yaw=yaw+math.pi

-		end

-		

-		-- this timer runs off every 2 seconds.

-		self.updatepct_timer=(self.updatepct_timer or 0)-dtime

-		local updatepct_timer_elapsed = self.updatepct_timer<=0

-		

-		if updatepct_timer_elapsed then

-			--restart timer

-			self.updatepct_timer=2

-			-- perform checks that are not frequently needed

-			

-			-- unload entity if out of range (because relevant pr won't be merged in engine)

-			-- This is a WORKAROUND!

-			local players_in = false

-			for sno,pname in pairs(data.seatp) do

-				if minetest.get_player_by_name(pname) then

-					-- Fix: If the RTT is too high, a wagon might be recognized out of range even if a player sits in it

-					-- (client updates position not fast enough)

-					players_in = true

-					break

-				end

-			end

-			if not players_in then

-				local outofrange = true

-				for _,p in pairs(minetest.get_connected_players()) do

-					if vector.distance(p:get_pos(),pos)<=unload_wgn_range then

-						outofrange = false

-					end

-				end

-				if outofrange then

-					--atdebug("wagon",self.id,"unloading (too far away)")

-					self.object:remove()

-				end

-			end

-		end

-		

-		if not self.old_velocity_vector 

-				or not vector.equals(velocityvec, self.old_velocity_vector)

-				or not self.old_acceleration_vector 

-				or not vector.equals(accelerationvec, self.old_acceleration_vector)

-				or self.old_yaw~=yaw

-				or updatepct_timer_elapsed then--only send update packet if something changed

-			

-			self.object:setpos(pos)

-			self.object:setvelocity(velocityvec)

-			self.object:setacceleration(accelerationvec)

-			

-			if #self.seats > 0 and self.old_yaw ~= yaw then

-				if not self.player_yaw then

-					self.player_yaw = {}

-				end

-				if not self.old_yaw then

-					self.old_yaw=yaw

-				end

-				for _,name in pairs(data.seatp) do

-					local p = minetest.get_player_by_name(name)

-					if p then

-						if not self.turning then

-							-- save player looking direction offset

-							self.player_yaw[name] = p:get_look_horizontal()-self.old_yaw

-						end

-						-- set player looking direction using calculated offset

-						p:set_look_horizontal((self.player_yaw[name] or 0)+yaw)

-					end

-				end

-				self.turning = true							 

-			elseif self.old_yaw == yaw then

-				-- train is no longer turning

-				self.turning = false

-			end

-			

-			if self.object.set_rotation then

-                local pitch = math.atan2(vdir.y, math.hypot(vdir.x, vdir.z))

-                if data.wagon_flipped then

-                    pitch = -pitch

-                end

-                self.object:set_rotation({x=pitch, y=yaw, z=0})

-            else

-                self.object:setyaw(yaw)

-            end

-			

-			if self.update_animation then

-				self:update_animation(train.velocity, self.old_velocity)

-			end

-			if self.custom_on_velocity_change then

-				self:custom_on_velocity_change(train.velocity, self.old_velocity or 0, dtime)

-			end

-			-- remove discouple object, because it will be in a wrong location

-			if not updatepct_timer_elapsed and self.discouple then

-				self.discouple.object:remove()

-			end

-		end

-		

-		

-		self.old_velocity_vector=velocityvec

-		self.old_velocity = train.velocity

-		self.old_acceleration_vector=accelerationvec

-		self.old_yaw=yaw

-		atprintbm("wagon step", t)

-	end)

-end

-

-function wagon:on_rightclick(clicker)

-	return advtrains.pcall(function()

-		if not self:ensure_init() then return end

-		if not clicker or not clicker:is_player() then

-			return

-		end

-		

-		local data = advtrains.wagons[self.id]

-		

-		local pname=clicker:get_player_name()

-		local no=self:get_seatno(pname)

-		if no then

-			if self.seat_groups then

-				local poss={}

-				local sgr=self.seats[no].group

-				for _,access in ipairs(self.seat_groups[sgr].access_to) do

-					if self:check_seat_group_access(pname, access) then

-						poss[#poss+1]={name=self.seat_groups[access].name, key="sgr_"..access}

-					end

-				end

-				if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-					poss[#poss+1]={name=attrans("Show Inventory"), key="inv"}

-				end

-				if self.seat_groups[sgr].driving_ctrl_access and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-					poss[#poss+1]={name=attrans("Onboard Computer"), key="bordcom"}

-				end

-				if data.owner==pname then

-					poss[#poss+1]={name=attrans("Wagon properties"), key="prop"}

-				end

-				if not self.seat_groups[sgr].require_doors_open or self:train().door_open~=0 then

-					poss[#poss+1]={name=attrans("Get off"), key="off"}

-				else

-					if clicker:get_player_control().sneak then

-						poss[#poss+1]={name=attrans("Get off (forced)"), key="off"}

-					else

-						poss[#poss+1]={name=attrans("(Doors closed)"), key="dcwarn"}

-					end

-				end

-				if #poss==0 then

-					--can't do anything.

-				elseif #poss==1 then

-					self:seating_from_key_helper(pname, {[poss[1].key]=true}, no)

-				else

-					local form = "size[5,"..1+(#poss).."]"

-					for pos,ent in ipairs(poss) do

-						form = form .. "button_exit[0.5,"..(pos-0.5)..";4,1;"..ent.key..";"..ent.name.."]"

-					end

-					minetest.show_formspec(pname, "advtrains_seating_"..self.id, form)

-				end

-			else

-				self:get_off(no)

-			end

-		else

-			--do not attach if already on a train

-			if advtrains.player_to_train_mapping[pname] then return end

-			if self.seat_groups then

-				if #self.seats==0 then

-					if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-						minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))

-					end

-					return

-				end

-				

-				local doors_open = self:train().door_open~=0 or clicker:get_player_control().sneak

-				local allow, rsn=false, "Wagon has no seats!"

-				for _,sgr in ipairs(self.assign_to_seat_group) do

-					allow, rsn = self:check_seat_group_access(pname, sgr)

-					if allow then

-						for seatid, seatdef in ipairs(self.seats) do

-							if seatdef.group==sgr then

-								if (not self.seat_groups[sgr].require_doors_open or doors_open) then

-									if not data.seatp[seatid] then

-										self:get_on(clicker, seatid)

-										return

-									else

-										rsn="Wagon is full."

-									end

-								else

-									rsn="Doors are closed! (try holding sneak key!)"

-								end

-							end

-						end

-					end

-				end

-				minetest.chat_send_player(pname, attrans("Can't get on: "..rsn))

-			else

-				self:show_get_on_form(pname)

-			end

-		end

-	end)

-end

-

-function wagon:get_on(clicker, seatno)

-	

-	local data = advtrains.wagons[self.id]

-		

-	if not data.seatp then data.seatp={}end

-	if not self.seatpc then self.seatpc={}end--player controls in driver stands

-	

-	if not self.seats[seatno] then return end

-	local oldno=self:get_seatno(clicker:get_player_name())

-	if oldno then

-		atprint("get_on: clearing oldno",seatno)

-		advtrains.player_to_train_mapping[clicker:get_player_name()]=nil

-		advtrains.clear_driver_hud(clicker:get_player_name())

-		data.seatp[oldno]=nil

-	end

-	if data.seatp[seatno] and data.seatp[seatno]~=clicker:get_player_name() then

-		atprint("get_on: throwing off",data.seatp[seatno],"from seat",seatno)

-		self:get_off(seatno)

-	end

-	atprint("get_on: attaching",clicker:get_player_name())

-	data.seatp[seatno] = clicker:get_player_name()

-	self.seatpc[seatno] = clicker:get_player_control_bits()

-	advtrains.player_to_train_mapping[clicker:get_player_name()]=data.train_id

-	clicker:set_attach(self.object, "", self.seats[seatno].attach_offset, {x=0,y=0,z=0})

-	clicker:set_eye_offset(self.seats[seatno].view_offset, self.seats[seatno].view_offset)

-end

-function wagon:get_off_plr(pname)

-	local no=self:get_seatno(pname)

-	if no then

-		self:get_off(no)

-	end

-end

-function wagon:get_seatno(pname)

-	

-	local data = advtrains.wagons[self.id]

-	

-	for no, cont in pairs(data.seatp) do

-		if cont==pname then

-			return no

-		end

-	end

-	return nil

-end

-function wagon:get_off(seatno)

-	

-	local data = advtrains.wagons[self.id]

-	

-	if not data.seatp[seatno] then return end

-	local pname = data.seatp[seatno]

-	local clicker = minetest.get_player_by_name(pname)

-	advtrains.player_to_train_mapping[pname]=nil

-	advtrains.clear_driver_hud(pname)

-	data.seatp[seatno]=nil

-	self.seatpc[seatno]=nil

-	if clicker then

-		atprint("get_off: detaching",clicker:get_player_name())

-		clicker:set_detach()

-		clicker:set_eye_offset({x=0,y=0,z=0}, {x=0,y=0,z=0})

-		local train=self:train()

-		--code as in step - automatic get on

-		if self.door_entry and train.door_open and train.door_open~=0 and train.velocity==0 and train.index and train.path then

-			local index = advtrains.path_get_index_by_offset(train, train.index, -data.pos_in_train)

-			for i, ino in ipairs(self.door_entry) do

-				--atdebug("using door-based",i,ino)

-				local fct=data.wagon_flipped and -1 or 1

-				local aci = advtrains.path_get_index_by_offset(train, index, ino*fct)

-				local ix1, ix2 = advtrains.path_get_adjacent(train, aci)

-				local d = train.door_open

-				if self.wagon_width then

-					d = d * math.floor(self.wagon_width/2)

-				end

-				-- the two wanted positions are ix1 and ix2 + (2nd-1st rotated by 90deg)

-				-- (x z) rotated by 90deg is (-z x)  (http://stackoverflow.com/a/4780141)

-				local add = { x = (ix2.z-ix1.z)*d, y = 0, z = (ix1.x-ix2.x)*d }

-				local oadd = { x = (ix2.z-ix1.z)*(d+train.door_open), y = 1, z = (ix1.x-ix2.x)*(d+train.door_open)}

-				local platpos=vector.round(vector.add(ix1, add))

-				local offpos=vector.round(vector.add(ix1, oadd))

-				

-				--atdebug("platpos:", platpos, "offpos:", offpos)

-				if minetest.get_item_group(minetest.get_node(platpos).name, "platform")>0 then

-					minetest.after(GETOFF_TP_DELAY, function() clicker:setpos(offpos) end)

-					--atdebug("tp",offpos)

-					return

-				end

-				--atdebug("nope")

-			end

-		end

-		--if not door_entry, or paths missing, fall back to old method

-		--atdebug("using fallback")

-		local objpos=advtrains.round_vector_floor_y(self.object:getpos())

-		local yaw=self.object:getyaw()

-		local isx=(yaw < math.pi/4) or (yaw > 3*math.pi/4 and yaw < 5*math.pi/4) or (yaw > 7*math.pi/4)

-		local offp

-		--abuse helper function

-		for _,r in ipairs({-1, 1}) do

-			--atdebug("offset",r)

-			local p=vector.add({x=isx and r or 0, y=0, z=not isx and r or 0}, objpos)

-			offp=vector.add({x=isx and r*2 or 0, y=1, z=not isx and r*2 or 0}, objpos)

-			--atdebug("platpos:", p, "offpos:", offp)

-			if minetest.get_item_group(minetest.get_node(p).name, "platform")>0 then

-				minetest.after(GETOFF_TP_DELAY, function() clicker:setpos(offp) end)

-				--atdebug("tp",offp)

-				return

-			end

-		end

-		--atdebug("nope")

-		

-	end

-end

-function wagon:show_get_on_form(pname)

-	if not self.initialized then return end

-	

-	local data = advtrains.wagons[self.id]

-	if #self.seats==0 then

-		if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-			minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))

-		end

-		return

-	end

-	local form, comma="size[5,8]label[0.5,0.5;"..attrans("Select seat:").."]textlist[0.5,1;4,6;seat;", ""

-	for seatno, seattbl in ipairs(self.seats) do

-		local addtext, colorcode="", ""

-		if data.seatp and data.seatp[seatno] then

-			colorcode="#FF0000"

-			addtext=" ("..data.seatp[seatno]..")"

-		end

-		form=form..comma..colorcode..seattbl.name..addtext

-		comma=","

-	end

-	form=form..";0,false]"

-	if self.has_inventory and self.get_inventory_formspec then

-		form=form.."button_exit[1,7;3,1;inv;"..attrans("Show Inventory").."]"

-	end

-	minetest.show_formspec(pname, "advtrains_geton_"..self.id, form)

-end

-function wagon:show_wagon_properties(pname)

-	--[[

-	fields: 

-	field: driving/couple whitelist

-	button: save

-	]]

-	local data = advtrains.wagons[self.id]

-	local form="size[5,5]"

-	form = form .. "field[0.5,1;4.5,1;whitelist;Allow these players to access your wagon:;"..minetest.formspec_escape(data.whitelist or "").."]"

-	form = form .. "field[0.5,2;4.5,1;roadnumber;Wagon road number:;"..minetest.formspec_escape(data.roadnumber or "").."]"

-	local fc = ""

-	if data.fc then

-		fc = table.concat(data.fc, "!")

-	end

-	form = form .. "field[0.5,3;4.5,1;fc;Freight Code:;"..fc.."]"

-	if data.fc then

-		if not data.fcind then data.fcind = 1 end

-		if data.fcind > 1 then

-			form=form.."button[0.5,3.5;1,1;fcp;prev FC]"

-		end

-		form=form.."label[1.5,3.5;Current FC:]"

-

-		local cur = data.fc[data.fcind] or ""

-		form=form.."label[1.5,3.75;"..minetest.formspec_escape(cur).."]"

-		form=form.."button[3.5,3.5;1,1;fcn;next FC]"

-	end

-	form=form.."button_exit[0.5,4.5;4,1;save;"..attrans("Save wagon properties").."]"

-	minetest.show_formspec(pname, "advtrains_prop_"..self.id, form)

-end

-

---BordCom

-local function checkcouple(ent)

-	if not ent or not ent:getyaw() then

-		return nil

-	end

-	local le = ent:get_luaentity()

-	if not le or not le.is_couple then

-		return nil

-	end

-	return le

-end

-local function checklock(pname, own1, own2, wl1, wl2)

-	return advtrains.check_driving_couple_protection(pname, own1, wl1)

-		or advtrains.check_driving_couple_protection(pname, own2, wl2)

-end

-

-local function split(str, sep)

-   local fields = {}

-   local pattern = string.format("([^%s]+)", sep)

-   str:gsub(pattern, function(c) fields[#fields+1] = c end)

-   return fields

-end

-

-function wagon.set_fc(data, fcstr)

-	data.fc = split(fcstr, "!")

-	if not data.fcind then

-		data.fcind = 1

-	elseif data.fcind > #data.fc then

-		data.fcind = #data.fc

-	end	

-end

-

-function wagon.prev_fc(data)

-	if data.fcind > 1 then

-		data.fcind = data.fcind -1

-	end

-	if data.fcind == 1 and data.fcrev then

-		data.fcrev = nil

-	end

-end

-

-function wagon.next_fc(data)

-	if not data.fc then return end

-	if data.fcrev then

-		wagon.prev_fc(data)

-		return

-	end

-	if data.fcind < #data.fc then

-		data.fcind = data.fcind + 1

-	else

-		data.fcind = 1

-	end

-	if data.fcind == #data.fc and data.fc[data.fcind] == "?" then

-		data.fcrev = true

-		wagon.prev_fc(data)

-		return			

-	end

-end

-

-function advtrains.get_cur_fc(data)

-	if not ( data.fc and data.fcind ) then

-		return ""

-	end

-	return data.fc[data.fcind] or ""

-end

-

-function advtrains.step_fc(data)

-	wagon.next_fc(data)

-end

-

-

-

-

-

-function wagon:show_bordcom(pname)

-	if not self:train() then return end

-	local train = self:train()

-	local data = advtrains.wagons[self.id]

-	

-	local form = "size[11,9]label[0.5,0;AdvTrains Boardcom v0.1]"

-	form=form.."textarea[0.5,1.5;7,1;text_outside;"..attrans("Text displayed outside on train")..";"..(minetest.formspec_escape(train.text_outside or "")).."]"

-	form=form.."textarea[0.5,3;7,1;text_inside;"..attrans("Text displayed inside train")..";"..(minetest.formspec_escape(train.text_inside or "")).."]"

-	form=form.."field[7.5,1.75;3,1;line;"..attrans("Line")..";"..(minetest.formspec_escape(train.line or "")).."]"

-	form=form.."field[7.5,3.25;3,1;routingcode;"..attrans("Routingcode")..";"..(minetest.formspec_escape(train.routingcode or "")).."]"

-	--row 5 : train overview and autocoupling

-	if train.velocity==0 then

-		form=form.."label[0.5,4;Train overview /coupling control:]"

-		linhei=5

-		local pre_own, pre_wl, owns_any = nil, nil, minetest.check_player_privs(pname, "train_admin")

-		for i, tpid in ipairs(train.trainparts) do

-			local ent = advtrains.wagons[tpid]

-			if ent then

-				local roadnumber = ent.roadnumber or ""

-				form = form .. string.format("button[%d,%d;%d,%d;%s;%s]", i, linhei, 1, 0.2, "wgprp"..i, roadnumber)

-				local ename = ent.type

-				form = form .. "item_image["..i..","..(linhei+0.5)..";1,1;"..ename.."]"

-				if i~=1 then

-					if checklock(pname, ent.owner, pre_own, ent.whitelist, pre_wl) then

-						form = form .. "image_button["..(i-0.5)..","..(linhei+1.5)..";1,1;advtrains_discouple.png;dcpl_"..i..";]"

-					end

-				end

-				if i == data.pos_in_trainparts then

-					form = form .. "box["..(i-0.1)..","..(linhei+0.4)..";1,1;green]"

-				end

-				pre_own = ent.owner

-				pre_wl = ent.whitelist

-				owns_any = owns_any or (not ent.owner or ent.owner==pname)

-			end

-		end

-		

-		if train.movedir==1 then

-			form = form .. "label["..(#train.trainparts+1)..","..(linhei)..";-->]"

-		else

-			form = form .. "label[0.5,"..(linhei)..";<--]"

-		end

-		--check cpl_eid_front and _back of train

-		local couple_front = checkcouple(train.cpl_front)

-		local couple_back = checkcouple(train.cpl_back)

-		if couple_front then

-			form = form .. "image_button[0.5,"..(linhei+1)..";1,1;advtrains_couple.png;cpl_f;]"

-		end

-		if couple_back then

-			form = form .. "image_button["..(#train.trainparts+0.5)..","..(linhei+1)..";1,1;advtrains_couple.png;cpl_b;]"

-		end

-		

-	else

-		form=form.."label[0.5,4.5;Train overview / coupling control is only shown when the train stands.]"

-	end

-	form = form .. "button[0.5,8;3,1;save;Save]"

-	

-	-- Interlocking functionality: If the interlocking module is loaded, you can set the signal aspect

-	-- from inside the train

-	if advtrains.interlocking and train.lzb and #train.lzb.oncoming > 0 then

-		local i=1

-		while train.lzb.oncoming[i] do

-			local oci = train.lzb.oncoming[i]

-			if oci.udata and oci.udata.signal_pos then

-				if advtrains.interlocking.db.get_sigd_for_signal(oci.udata.signal_pos) then

-					form = form .. "button[4.5,8;5,1;ilrs;Remote Routesetting]"

-					break

-				end

-			end

-			i=i+1

-		end

-	end

-	

-	minetest.show_formspec(pname, "advtrains_bordcom_"..self.id, form)

-end

-function wagon:handle_bordcom_fields(pname, formname, fields)

-	local data = advtrains.wagons[self.id]

-	

-	local seatno=self:get_seatno(pname)

-	if not seatno or not self.seat_groups[self.seats[seatno].group].driving_ctrl_access or not advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-		return

-	end

-	local train = self:train()

-	if not train then return end

-	if fields.text_outside then

-		if fields.text_outside~="" then

-			train.text_outside=fields.text_outside

-		else

-			train.text_outside=nil

-		end

-	end

-	if fields.text_inside then

-		if fields.text_inside~="" then

-			train.text_inside=fields.text_inside

-		else

-			train.text_inside=nil

-		end

-	end

-	if fields.line then

-		if fields.line~="" then

-			if fields.line ~= train.line then

-				train.line=fields.line

-				minetest.after(0, advtrains.invalidate_path, train.id)

-			end

-		else

-			train.line=nil

-		end

-	end

-	if fields.routingcode then

-		if fields.routingcode~="" then

-			if fields.routingcode ~= train.routingcode then

-				train.routingcode=fields.routingcode

-				minetest.after(0, advtrains.invalidate_path, train.id)

-			end

-		else

-			train.routingcode=nil

-		end

-	end

-	for i, tpid in ipairs(train.trainparts) do

-		if fields["dcpl_"..i] then

-			advtrains.safe_decouple_wagon(tpid, pname)

-		elseif fields["wgprp"..i] then

-			for _,wagon in pairs(minetest.luaentities) do

-				if wagon.is_wagon and wagon.initialized and wagon.id==tpid and data.owner==pname then

-					wagon:show_wagon_properties(pname)

-					return

-				end

-			end

-		end

-	end

-	--check cpl_eid_front and _back of train

-	local couple_front = checkcouple(train.cpl_front)

-	local couple_back = checkcouple(train.cpl_back)

-	

-	if fields.cpl_f and couple_front then

-		couple_front:on_rightclick(pname)

-	end

-	if fields.cpl_b and couple_back then

-		couple_back:on_rightclick(pname)

-	end

-	

-	-- Interlocking functionality: If the interlocking module is loaded, you can set the signal aspect

-	-- from inside the train

-	if fields.ilrs and advtrains.interlocking and train.lzb and #train.lzb.oncoming > 0 then

-		local i=1

-		while train.lzb.oncoming[i] do

-			local oci = train.lzb.oncoming[i]

-			if oci.udata and oci.udata.signal_pos then

-				local sigd = advtrains.interlocking.db.get_sigd_for_signal(oci.udata.signal_pos)

-				if sigd then

-					advtrains.interlocking.show_signalling_form(sigd, pname)

-					return

-				end

-			end

-			i=i+1

-		end

-	end

-	

-	

-	if not fields.quit then

-		self:show_bordcom(pname)

-	end

-end

-

-minetest.register_on_player_receive_fields(function(player, formname, fields)

-	return advtrains.pcall(function()

-		local uid=string.match(formname, "^advtrains_geton_(.+)$")

-		if uid then

-			for _,wagon in pairs(minetest.luaentities) do

-				if wagon.is_wagon and wagon.initialized and wagon.id==uid then

-					local data = advtrains.wagons[wagon.id]

-					if fields.inv then

-						if wagon.has_inventory and wagon.get_inventory_formspec then

-							minetest.show_formspec(player:get_player_name(), "advtrains_inv_"..uid, wagon:get_inventory_formspec(player:get_player_name(), make_inv_name(uid)))

-						end

-					elseif fields.seat then

-						local val=minetest.explode_textlist_event(fields.seat)

-						if val and val.type~="INV" and not data.seatp[player:get_player_name()] then

-						--get on

-							wagon:get_on(player, val.index)

-							--will work with the new close_formspec functionality. close exactly this formspec.

-							minetest.show_formspec(player:get_player_name(), formname, "")

-						end

-					end

-				end

-			end

-		end

-		uid=string.match(formname, "^advtrains_seating_(.+)$")

-		if uid then

-			for _,wagon in pairs(minetest.luaentities) do

-				if wagon.is_wagon and wagon.initialized and wagon.id==uid then

-					local pname=player:get_player_name()

-					local no=wagon:get_seatno(pname)

-					if no then

-						if wagon.seat_groups then

-							wagon:seating_from_key_helper(pname, fields, no)

-						end

-					end

-				end

-			end

-		end

-		uid=string.match(formname, "^advtrains_prop_(.+)$")

-		if uid then

-			local pname=player:get_player_name()

-			local data = advtrains.wagons[uid]

-			if pname~=data.owner and not minetest.check_player_privs(pname, {train_admin = true}) then

-				return true

-			end

-			if fields.save or not fields.quit then

-				if fields.whitelist then

-					data.whitelist = fields.whitelist

-				end

-				if fields.roadnumber then

-					data.roadnumber = fields.roadnumber

-				end

-				if fields.fc then

-					wagon.set_fc(data, fields.fc)

-				end

-				if fields.fcp then

-					wagon.prev_fc(data)

-					wagon.show_wagon_properties({id=uid}, pname)

-				end

-				if fields.fcn then

-					advtrains.step_fc(data)

-					wagon.show_wagon_properties({id=uid}, pname)

-				end

-			end

-		end

-		uid=string.match(formname, "^advtrains_bordcom_(.+)$")

-		if uid then

-			for _,wagon in pairs(minetest.luaentities) do

-				if wagon.is_wagon and wagon.initialized and wagon.id==uid then

-					wagon:handle_bordcom_fields(player:get_player_name(), formname, fields)

-				end

-			end

-		end

-		uid=string.match(formname, "^advtrains_inv_(.+)$")

-		if uid then

-			local pname=player:get_player_name()

-			local data = advtrains.wagons[uid]

-			if fields.prop and data.owner==pname then

-				for _,wagon in pairs(minetest.luaentities) do

-					if wagon.is_wagon and wagon.initialized and wagon.id==uid and data.owner==pname then

-						wagon:show_wagon_properties(pname)

-						--wagon:handle_bordcom_fields(player:get_player_name(), formname, fields)

-					end

-				end

-			end

-		end

-	end)

-end)

-function wagon:seating_from_key_helper(pname, fields, no)

-	local data = advtrains.wagons[self.id]

-	local sgr=self.seats[no].group

-	for _,access in ipairs(self.seat_groups[sgr].access_to) do

-		if fields["sgr_"..access] and self:check_seat_group_access(pname, access) then

-			for seatid, seatdef in ipairs(self.seats) do

-				if seatdef.group==access and not data.seatp[seatid] then

-					self:get_on(minetest.get_player_by_name(pname), seatid)

-					return

-				end

-			end

-		end

-	end

-	if fields.inv and self.has_inventory and self.get_inventory_formspec then

-		minetest.close_formspec(pname, "advtrains_seating_"..self.id)

-		minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))

-	end

-	if fields.prop and data.owner==pname then

-		minetest.close_formspec(pname, "advtrains_seating_"..self.id)

-		self:show_wagon_properties(pname)

-	end

-	if fields.bordcom and self.seat_groups[sgr].driving_ctrl_access and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then

-		minetest.close_formspec(pname, "advtrains_seating_"..self.id)

-		self:show_bordcom(pname)

-	end

-	if fields.dcwarn then

-		minetest.chat_send_player(pname, attrans("Doors are closed! Use Sneak+rightclick to ignore the closed doors and get off!"))

-	end

-	if fields.off then

-		self:get_off(no)

-	end

-end

-function wagon:check_seat_group_access(pname, sgr)

-	local data = advtrains.wagons[self.id]

-	if self.seat_groups[sgr].driving_ctrl_access and not (advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist)) then

-		return false, "Not allowed to access a driver stand!"

-	end

-	if self.seat_groups[sgr].driving_ctrl_access then

-		advtrains.log("Drive", pname, self.object:getpos(), self:train().text_outside)

-	end

-	return true

-end

-function wagon:reattach_all()

-	local data = advtrains.wagons[self.id]

-	if not data.seatp then data.seatp={} end

-	for seatno, pname in pairs(data.seatp) do

-		local p=minetest.get_player_by_name(pname)

-		if p then

-			self:get_on(p ,seatno)

-		end

-	end

-end

-

-local function check_twagon_owner(train, b_first, pname)

-	local wtp = b_first and 1 or #train.trainparts

-	local wid = train.trainparts[wtp]

-	local wdata = advtrains.wagons[wid]

-	if wdata then

-		return advtrains.check_driving_couple_protection(pname, wdata.owner, wdata.whitelist)

-	end

-	return false

-end

-

-function advtrains.safe_couple_trains(id1, id2, t1f, t2f, pname, try_run,v1,v2)

-	

-	if pname and not minetest.check_player_privs(pname, "train_operator") then

-		minetest.chat_send_player(pname, "Missing train_operator privilege")

-		return false

-	end

-	

-	local train1=advtrains.trains[id1]

-	local train2=advtrains.trains[id2]

-	

-	if not advtrains.train_ensure_init(id1, train1)

-		or not advtrains.train_ensure_init(id2, train2) then

-		return false

-	end

-	local wck_t1, wck_t2

-	if pname then

-		wck_t1 = check_twagon_owner(train1, t1f, pname)

-		wck_t2 = check_twagon_owner(train2, t2f, pname)

-	end

-	if (wck_t1 or wck_t2) or not pname then

-		if not v1 then

-			v1 = 0

-		end

-		if not v2 then

-			v2 = 0

-		end

-		if try_run then

-			return true

-		end

-		if t1f then

-			if t2f then

-				v1 = -v1

-				advtrains.invert_train(id1)

-				advtrains.do_connect_trains(id1, id2, v1+v2)

-			else

-				advtrains.do_connect_trains(id2, id1, v1+v2)

-			end

-		else

-			if t2f then

-				advtrains.do_connect_trains(id1, id2, v1+v2)

-			else

-				v2 = -v2

-				advtrains.invert_train(id2)

-				advtrains.do_connect_trains(id1, id2, v1+v2)

-			end

-		end

-		return true

-	else

-		minetest.chat_send_player(pname, "You must be authorized for at least one wagon.")

-		return false

-	end

-end

-

-

-function advtrains.safe_decouple_wagon(w_id, pname, try_run)

-	if not minetest.check_player_privs(pname, "train_operator") then

-		minetest.chat_send_player(pname, "Missing train_operator privilege")

-		return false

-	end

-	local data = advtrains.wagons[w_id]

-	

-	local dpt = data.pos_in_trainparts

-	if not dpt or dpt <= 1 then

-		return false

-	end

-	local train = advtrains.trains[data.train_id]

-	local owid = train.trainparts[dpt-1]

-	local owdata = advtrains.wagons[owid]

-	

-	if not owdata then

-		return

-	end

-	

-	if not checklock(pname, data.owner, owdata.owner, data.whitelist, owdata.whitelist) then

-		minetest.chat_send_player(pname, "Not allowed to do this.")

-		return false

-	end

-	

-	if try_run then

-		return true

-	end

-	

-	advtrains.log("Discouple", pname, train.last_pos, train.text_outside)

-	advtrains.split_train_at_wagon(w_id)

-	return true

-end

-

-

-

-function advtrains.get_wagon_prototype(data)

-	local wt = data.type

-	if not wt then

-		-- LEGACY: Field was called "entity_name" in previous versions

-		wt = data.entity_name

-		data.type = data.entity_name

-		data.entity_name = nil

-	end

-	if not wt or not advtrains.wagon_prototypes[wt] then

-		atwarn("Unable to load wagon type",wt,", using placeholder")

-		wt="advtrains:wagon_placeholder"

-	end

-	return wt, advtrains.wagon_prototypes[wt]

-end

-

-function advtrains.standard_inventory_formspec(self, pname, invname)

-	--[[minetest.chat_send_player(pname, string.format("self=%s, pname=%s, invname=%s", self, pname, invname))

-	for k,v in pairs(self) do

-		minetest.chat_send_player(pname, string.format("%s=%s", k,v))

-	end

-	minetest.chat_send_player(pname, string.format("***%s***", self.object:get_pos()))--]]

-	local data = advtrains.wagons[self.id]

-	local r = "size[8,11]"..

-			"list["..invname..";box;0,0;8,3;]"

-	if data.owner==pname then

-		r = r .. "button_exit[0,9;4,1;prop;"..attrans("Wagon properties").."]"

-	end

-	r = r .. "list[current_player;main;0,5;8,4;]"..

-			"listring[]"

-	return r

-end

-

-function advtrains.register_wagon(sysname_p, prototype, desc, inv_img, nincreative)

-	local sysname = sysname_p

-	if not string.match(sysname, ":") then

-		sysname = "advtrains:"..sysname_p

-	end

-	setmetatable(prototype, {__index=wagon})

-	minetest.register_entity(":"..sysname,prototype)

-	advtrains.wagon_prototypes[sysname] = prototype

-	

-	minetest.register_craftitem(":"..sysname, {

-		description = desc,

-		inventory_image = inv_img,

-		wield_image = inv_img,

-		stack_max = 1,

-		

-		groups = { not_in_creative_inventory = nincreative and 1 or 0},

-		

-		on_place = function(itemstack, placer, pointed_thing)

-			return advtrains.pcall(function()

-				if not pointed_thing.type == "node" then

-					return

-				end

-				local pname = placer:get_player_name()

-

-				local node=minetest.get_node_or_nil(pointed_thing.under)

-				if not node then atprint("[advtrains]Ignore at placer position") return itemstack end

-				local nodename=node.name

-				if(not advtrains.is_track_and_drives_on(nodename, prototype.drives_on)) then

-					atprint("no track here, not placing.")

-					return itemstack

-				end

-				if not minetest.check_player_privs(placer, {train_operator = true }) then

-					minetest.chat_send_player(pname, "You don't have the train_operator privilege.")

-					return itemstack

-				end

-				if not minetest.check_player_privs(placer, {train_admin = true }) and minetest.is_protected(pointed_thing.under, placer:get_player_name()) then

-					return itemstack

-				end

-				local tconns=advtrains.get_track_connections(node.name, node.param2)

-				local yaw = placer:get_look_horizontal()

-				local plconnid = advtrains.yawToClosestConn(yaw, tconns)

-				

-				local prevpos = advtrains.get_adjacent_rail(pointed_thing.under, tconns, plconnid, prototype.drives_on)

-				if not prevpos then

-					minetest.chat_send_player(pname, "The track you are trying to place the wagon on is not long enough!")

-					return

-				end

-				

-				local wid = advtrains.create_wagon(sysname, pname)

-				

-				local id=advtrains.create_new_train_at(pointed_thing.under, plconnid, 0, {wid})

-				

-				if not advtrains.is_creative(pname) then

-					itemstack:take_item()

-				end

-				return itemstack

-				

-			end)

-		end,

-	})

-end

-

--- Placeholder wagon. Will be spawned whenever a mod is missing

-advtrains.register_wagon("advtrains:wagon_placeholder", {

-	visual="sprite",

-	textures = {"advtrains_wagon_placeholder.png"},

-	collisionbox = {-0.3,-0.3,-0.3, 0.3,0.3,0.3},

-	visual_size = {x=0.7, y=0.7},

-	initial_sprite_basepos = {x=0, y=0},

-	drives_on = advtrains.all_tracktypes,

-	max_speed = 5,

-	seats = {

-	},

-	seat_groups = {

-	},

-	assign_to_seat_group = {},

-	wagon_span=1,

-	drops={},

-}, "Wagon placeholder", "advtrains_wagon_placeholder.png", true)

-

+-- wagon.lua
+-- Holds all logic related to wagons
+-- From now on, wagons are, just like trains, just entries in a table
+-- All data that is static is stored in the entity prototype (self).
+--   A copy of the entity prototype is always available inside wagon_prototypes
+-- All dynamic data is stored in the (new) wagons table
+-- An entity is ONLY spawned by update_trainpart_properties when it finds it useful.
+-- Only data that are only important to the entity itself are stored in the luaentity
+
+-- TP delay when getting off wagon
+local GETOFF_TP_DELAY = 0.5
+
+advtrains.wagons = {}
+advtrains.wagon_prototypes = {}
+advtrains.wagon_objects = {}
+
+local unload_wgn_range = advtrains.wagon_load_range + 32
+
+local setting_show_ids = minetest.settings:get_bool("advtrains_show_ids")
+
+--
+function advtrains.create_wagon(wtype, owner)
+	local new_id=advtrains.random_id()
+	while advtrains.wagons[new_id] do new_id=advtrains.random_id() end
+	local wgn = {}
+	wgn.type = wtype
+	wgn.seatp = {}
+	wgn.owner = owner
+	wgn.id = new_id
+	---wgn.train_id = train_id   --- will get this via update_trainpart_properties
+	advtrains.wagons[new_id] = wgn
+	--atdebug("Created new wagon:",wgn)
+	return new_id
+end
+
+local function make_inv_name(uid)
+	return "detached:advtrains_wgn_"..uid
+end
+
+
+local wagon={
+	collisionbox = {-0.5,-0.5,-0.5, 0.5,0.5,0.5},
+	--physical = true,
+	visual = "mesh",
+	mesh = "wagon.b3d",
+	visual_size = {x=1, y=1},
+	textures = {"black.png"},
+	is_wagon=true,
+	wagon_span=1,--how many index units of space does this wagon consume
+	wagon_width=3, -- Wagon width in meters
+	has_inventory=false,
+	static_save=false,
+}
+
+
+function wagon:train()
+	local data = advtrains.wagons[self.id]
+	return advtrains.trains[data.train_id]
+end
+
+
+function wagon:on_activate(sd_uid, dtime_s)
+	if sd_uid~="" then
+		--destroy when loaded from static block.
+		self.object:remove()
+		return
+	end
+	self.object:set_armor_groups({immortal=1})
+end
+
+local function invcallback(id, pname, rtallow, rtfail)
+	local data = advtrains.wagons[id]
+	if data and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+		return rtallow
+	end
+	return rtfail
+end
+
+function wagon:set_id(wid)
+	self.id = wid
+	self.initialized = true
+	
+	local data = advtrains.wagons[self.id]
+	advtrains.wagon_objects[self.id] = self.object
+	
+	--atdebug("Created wagon entity:",self.name," w_id",wid," t_id",data.train_id)
+	
+	if self.has_inventory then
+		--to be used later
+		local inv=minetest.get_inventory({type="detached", name="advtrains_wgn_"..self.id})
+		-- create inventory, if not yet created
+		if not inv then	
+			inv=minetest.create_detached_inventory("advtrains_wgn_"..self.id, {
+				allow_move = function(inv, from_list, from_index, to_list, to_index, count, player)
+					return invcallback(wid, player:get_player_name(), count, 0)
+				end,
+				allow_put = function(inv, listname, index, stack, player)
+					return invcallback(wid, player:get_player_name(), stack:get_count(), 0)
+				end,
+				allow_take = function(inv, listname, index, stack, player)
+					return invcallback(wid, player:get_player_name(), stack:get_count(), 0)
+				end
+			})
+			if data.ser_inv then
+				advtrains.deserialize_inventory(data.ser_inv, inv)
+			end
+			if self.inventory_list_sizes then
+				for lst, siz in pairs(self.inventory_list_sizes) do
+					inv:set_size(lst, siz)
+				end
+			end
+		end
+	end
+	self.door_anim_timer=0
+	self.door_state=0
+	
+	minetest.after(0.2, function() self:reattach_all() end)
+	
+	
+	
+	if self.set_textures then
+		self:set_textures(data)
+	end
+	
+	if self.custom_on_activate then
+		self:custom_on_activate()
+	end
+end
+
+function wagon:get_staticdata()
+	return "STATIC"
+end
+
+function wagon:ensure_init()
+			-- Note: A wagon entity won't exist when there's no train, because the train is
+			-- the thing that actually creates the entity
+			-- Train not being set just means that this will happen as soon as the train calls update_trainpart_properties.
+	if self.initialized and self.id then
+		local data = advtrains.wagons[self.id]
+		if data and data.train_id and self:train() then
+			if self.noninitticks then self.noninitticks=nil end
+			return true
+		end
+	end
+	if not self.noninitticks then
+		atwarn("wagon",self.id,"uninitialized init=",self.initialized)
+		self.noninitticks=0
+	end
+	self.noninitticks=self.noninitticks+1
+	if self.noninitticks>20 then
+		atwarn("wagon",self.id,"uninitialized, removing")
+		self:destroy()
+	else
+		self.object:setvelocity({x=0,y=0,z=0})
+	end
+	return false
+end
+
+function wagon:train()
+	local data = advtrains.wagons[self.id]
+	return advtrains.trains[data.train_id]
+end
+
+-- Remove the wagon
+function wagon:on_punch(puncher, time_from_last_punch, tool_capabilities, direction)
+	return advtrains.pcall(function()
+		if not self:ensure_init() then return end
+		
+		local data = advtrains.wagons[self.id]
+	
+		if not puncher or not puncher:is_player() then
+			return
+		end
+		if data.owner and puncher:get_player_name()~=data.owner and (not minetest.check_player_privs(puncher, {train_admin = true })) then
+		   minetest.chat_send_player(puncher:get_player_name(), attrans("This wagon is owned by @1, you can't destroy it.", data.owner));
+		   return
+		end
+		
+		if self.custom_may_destroy then
+			if not self.custom_may_destroy(self, puncher, time_from_last_punch, tool_capabilities, direction) then
+				return
+			end
+		end
+		local itemstack = puncher:get_wielded_item()
+		-- WARNING: This part of the API is guaranteed to change! DO NOT USE!
+		if self.set_livery and itemstack:get_name() == "bike:painter" then
+			self:set_livery(puncher, itemstack, data)
+			return
+		end
+		-- check whether wagon has an inventory. Is is empty?
+		if self.has_inventory then
+			local inv=minetest.get_inventory({type="detached", name="advtrains_wgn_"..self.id})
+			if not inv then -- inventory is not initialized when wagon was never loaded - should never happen
+				atwarn("Destroying wagon with inventory, but inventory is not found? Shouldn't happen!")
+				return
+			end
+			for listname, _ in pairs(inv:get_lists()) do
+				if not inv:is_empty(listname) then
+					minetest.chat_send_player(puncher:get_player_name(), attrans("The wagon's inventory is not empty!"));
+					return
+				end
+			end
+		end
+		
+		if #(self:train().trainparts)>1 then
+		   minetest.chat_send_player(puncher:get_player_name(), attrans("Wagon needs to be decoupled from other wagons in order to destroy it."));
+		   return
+		end
+
+		local pc=puncher:get_player_control()
+		if not pc.sneak then
+			minetest.chat_send_player(puncher:get_player_name(), attrans("Warning: If you destroy this wagon, you only get some steel back! If you are sure, hold Sneak and left-click the wagon."))
+			return
+		end
+		
+		
+		if not self:destroy() then return end
+
+		local inv = puncher:get_inventory()
+		for _,item in ipairs(self.drops or {self.name}) do
+			inv:add_item("main", item)
+		end
+	end)
+end
+function wagon:destroy()
+	--some rules:
+	-- you get only some items back
+	-- single left-click shows warning
+	-- shift leftclick destroys
+	-- not when a driver is inside
+	if self.id then
+		local data = advtrains.wagons[self.id]
+		if not data then
+			atwarn("wagon:destroy(): data is not set!")
+			return
+		end
+		
+		if self.custom_on_destroy then
+			self.custom_on_destroy(self)
+		end
+		
+		for seat,_ in pairs(data.seatp) do
+			self:get_off(seat)
+		end
+		
+		if data.train_id and self:train() then
+			advtrains.remove_train(data.train_id)
+			advtrains.wagons[self.id]=nil
+			if self.discouple then self.discouple.object:remove() end--will have no effect on unloaded objects
+		end
+	end
+	--atdebug("[wagon ", self.id, "]: destroying")
+	
+	self.object:remove()
+	return true
+end
+
+function wagon:on_step(dtime)
+	return advtrains.pcall(function()
+		if not self:ensure_init() then return end
+		
+		local t=os.clock()
+		local pos = self.object:getpos()
+		local data = advtrains.wagons[self.id]
+		
+		if not pos then
+			--atdebug("["..self.id.."][fatal] missing position (object:getpos() returned nil)")
+			return
+		end
+		
+		if not data.seatp then
+			data.seatp={}
+		end
+		if not self.seatpc then
+			self.seatpc={}
+		end
+		
+		local train=self:train()
+
+		--custom on_step function
+		if self.custom_on_step then
+			self:custom_on_step(dtime, data, train)
+		end
+
+		--driver control
+		for seatno, seat in ipairs(self.seats) do
+			local pname=data.seatp[seatno]
+			local driver=pname and minetest.get_player_by_name(pname)
+			local has_driverstand = pname and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist)
+			if self.seat_groups then
+				has_driverstand = has_driverstand and (seat.driving_ctrl_access or self.seat_groups[seat.group].driving_ctrl_access)
+			else
+				has_driverstand = has_driverstand and (seat.driving_ctrl_access)
+			end
+			if has_driverstand and driver then
+				advtrains.update_driver_hud(driver:get_player_name(), self:train(), data.wagon_flipped)
+			elseif driver then
+				--only show the inside text
+				local inside=self:train().text_inside or ""
+				advtrains.set_trainhud(driver:get_player_name(), inside)
+			end
+			if driver and driver:get_player_control_bits()~=self.seatpc[seatno] then
+				local pc=driver:get_player_control()
+				self.seatpc[seatno]=driver:get_player_control_bits()
+				
+				if has_driverstand then
+					--regular driver stand controls
+					advtrains.on_control_change(pc, self:train(), data.wagon_flipped)
+					--bordcom
+					if pc.sneak and pc.jump then
+						self:show_bordcom(data.seatp[seatno])
+					end
+					--sound horn when required
+					if self.horn_sound and pc.aux1 and not pc.sneak and not self.horn_handle then
+						self.horn_handle = minetest.sound_play(self.horn_sound, {
+							object = self.object,
+							gain = 1.0, -- default
+							max_hear_distance = 128, -- default, uses an euclidean metric
+							loop = true,
+						})
+					elseif not pc.aux1 and self.horn_handle then
+						minetest.sound_stop(self.horn_handle)
+						self.horn_handle = nil
+					end
+				else
+					-- If on a passenger seat and doors are open, get off when W or D pressed.
+					local pass = data.seatp[seatno] and minetest.get_player_by_name(data.seatp[seatno])
+					if pass and self:train().door_open~=0 then
+					local pc=pass:get_player_control()
+						if pc.up or pc.down then
+							self:get_off(seatno)
+						end
+					end		      
+				end
+				if pc.aux1 and pc.sneak then
+					self:get_off(seatno)
+				end
+			end
+		end
+		
+		--check infotext
+		local outside=train.text_outside or ""
+		if setting_show_ids then
+			outside = outside .. "\nT:" .. data.train_id .. " W:" .. self.id .. " O:" .. data.owner
+		end
+		
+		
+		--show off-track information in outside text instead of notifying the whole server about this
+		if train.off_track then
+			outside = outside .."\n!!! Train off track !!!"
+		end
+		
+		if self.infotext_cache~=outside  then
+			self.object:set_properties({infotext=outside})
+			self.infotext_cache=outside
+		end
+		
+		local fct=data.wagon_flipped and -1 or 1
+		
+		--door animation
+		if self.doors then
+			if (self.door_anim_timer or 0)<=0 then
+				local dstate = (train.door_open or 0) * fct
+				if dstate ~= self.door_state then
+					local at
+					--meaning of the train.door_open field:
+					-- -1: left doors (rel. to train orientation)
+					--  0: closed
+					--  1: right doors
+					--this code produces the following behavior:
+					-- if changed from 0 to +-1, play open anim. if changed from +-1 to 0, play close.
+					-- if changed from +-1 to -+1, first close and set 0, then it will detect state change again and run open.
+					if self.door_state == 0 then
+						if self.doors.open.sound then minetest.sound_play(self.doors.open.sound, {object = self.object}) end
+						at=self.doors.open[dstate]
+						self.object:set_animation(at.frames, at.speed or 15, at.blend or 0, false)
+						self.door_state = dstate
+					else
+						if self.doors.close.sound then minetest.sound_play(self.doors.close.sound, {object = self.object}) end
+						at=self.doors.close[self.door_state or 1]--in case it has not been set yet
+						self.object:set_animation(at.frames, at.speed or 15, at.blend or 0, false)
+						self.door_state = 0
+					end
+					self.door_anim_timer = at.time
+				end
+			else
+				self.door_anim_timer = (self.door_anim_timer or 0) - dtime
+			end
+		end
+		
+		--for path to be available. if not, skip step
+		if not train.path or train.no_step then
+			self.object:setvelocity({x=0, y=0, z=0})
+			self.object:setacceleration({x=0, y=0, z=0})
+			return
+		end
+		if not data.pos_in_train then
+			return
+		end
+		
+		-- Calculate new position, yaw and direction vector
+		local index = advtrains.path_get_index_by_offset(train, train.index, -data.pos_in_train)
+		local pos, yaw, npos, npos2 = advtrains.path_get_interpolated(train, index)
+		local vdir = vector.normalize(vector.subtract(npos2, npos))
+		
+		--automatic get_on
+		--needs to know index and path
+		if self.door_entry and train.door_open and train.door_open~=0 and train.velocity==0 then
+			--using the mapping created by the trainlogic globalstep
+			for i, ino in ipairs(self.door_entry) do
+				--fct is the flipstate flag from door animation above
+				local aci = advtrains.path_get_index_by_offset(train, index, ino*fct)
+				local ix1, ix2 = advtrains.path_get_adjacent(train, aci)
+				-- the two wanted positions are ix1 and ix2 + (2nd-1st rotated by 90deg)
+				-- (x z) rotated by 90deg is (-z x)  (http://stackoverflow.com/a/4780141)
+				local add = { x = (ix2.z-ix1.z)*train.door_open, y = 0, z = (ix1.x-ix2.x)*train.door_open }
+				local pts1=vector.round(vector.add(ix1, add))
+				local pts2=vector.round(vector.add(ix2, add))
+				if minetest.get_item_group(minetest.get_node(pts1).name, "platform")>0 then
+					local ckpts={
+						pts1,
+						pts2,
+						vector.add(pts1, {x=0, y=1, z=0}),
+						vector.add(pts2, {x=0, y=1, z=0}),
+					}
+					for _,ckpos in ipairs(ckpts) do
+						local cpp=minetest.pos_to_string(ckpos)
+						if advtrains.playersbypts[cpp] then
+							self:on_rightclick(advtrains.playersbypts[cpp])
+						end
+					end
+				end
+			end
+		end
+		
+		--checking for environment collisions(a 3x3 cube around the center)
+		if not train.recently_collided_with_env then
+			local collides=false
+			local exh = self.extent_h or 1
+			local exv = self.extent_v or 2
+			for x=-exh,exh do
+				for y=0,exv do
+					for z=-exh,exh do
+						local node=minetest.get_node_or_nil(vector.add(npos, {x=x, y=y, z=z}))
+						if (advtrains.train_collides(node)) then
+							collides=true
+						end
+					end
+				end
+			end
+			if collides then
+				-- screw collision mercy
+				train.recently_collided_with_env=true
+				train.velocity=0
+				advtrains.atc.train_reset_command(train)
+			end
+		end
+		
+		--DisCouple
+		-- FIX: Need to do this after the yaw calculation
+		if data.pos_in_trainparts and data.pos_in_trainparts>1 then
+			if train.velocity==0 then
+				if not self.discouple or not self.discouple.object:getyaw() then
+					atprint(self.id,"trying to spawn discouple")
+					local dcpl_pos = vector.add(pos, {y=0, x=-math.sin(yaw)*self.wagon_span, z=math.cos(yaw)*self.wagon_span})
+					local object=minetest.add_entity(dcpl_pos, "advtrains:discouple")
+					if object then
+						local le=object:get_luaentity()
+						le.wagon=self
+						--box is hidden when attached, so unuseful.
+						--object:set_attach(self.object, "", {x=0, y=0, z=self.wagon_span*10}, {x=0, y=0, z=0})
+						self.discouple=le
+					end
+				end
+			else
+				if self.discouple and self.discouple.object:getyaw() then
+					self.discouple.object:remove()
+					atprint(self.id," removing discouple")
+				end
+			end
+		end
+		
+		--FIX: use index of the wagon, not of the train.
+		local velocity = train.velocity
+		local acceleration = (train.acceleration or 0)
+		local velocityvec = vector.multiply(vdir, velocity)
+		local accelerationvec = vector.multiply(vdir, acceleration)
+		
+		if data.wagon_flipped then
+			yaw=yaw+math.pi
+		end
+		
+		-- this timer runs off every 2 seconds.
+		self.updatepct_timer=(self.updatepct_timer or 0)-dtime
+		local updatepct_timer_elapsed = self.updatepct_timer<=0
+		
+		if updatepct_timer_elapsed then
+			--restart timer
+			self.updatepct_timer=2
+			-- perform checks that are not frequently needed
+			
+			-- unload entity if out of range (because relevant pr won't be merged in engine)
+			-- This is a WORKAROUND!
+			local players_in = false
+			for sno,pname in pairs(data.seatp) do
+				if minetest.get_player_by_name(pname) then
+					-- Fix: If the RTT is too high, a wagon might be recognized out of range even if a player sits in it
+					-- (client updates position not fast enough)
+					players_in = true
+					break
+				end
+			end
+			if not players_in then
+				local outofrange = true
+				for _,p in pairs(minetest.get_connected_players()) do
+					if vector.distance(p:get_pos(),pos)<=unload_wgn_range then
+						outofrange = false
+					end
+				end
+				if outofrange then
+					--atdebug("wagon",self.id,"unloading (too far away)")
+					self.object:remove()
+				end
+			end
+		end
+		
+		if not self.old_velocity_vector 
+				or not vector.equals(velocityvec, self.old_velocity_vector)
+				or not self.old_acceleration_vector 
+				or not vector.equals(accelerationvec, self.old_acceleration_vector)
+				or self.old_yaw~=yaw
+				or updatepct_timer_elapsed then--only send update packet if something changed
+			
+			self.object:setpos(pos)
+			self.object:setvelocity(velocityvec)
+			self.object:setacceleration(accelerationvec)
+			
+			if #self.seats > 0 and self.old_yaw ~= yaw then
+				if not self.player_yaw then
+					self.player_yaw = {}
+				end
+				if not self.old_yaw then
+					self.old_yaw=yaw
+				end
+				for _,name in pairs(data.seatp) do
+					local p = minetest.get_player_by_name(name)
+					if p then
+						if not self.turning then
+							-- save player looking direction offset
+							self.player_yaw[name] = p:get_look_horizontal()-self.old_yaw
+						end
+						-- set player looking direction using calculated offset
+						p:set_look_horizontal((self.player_yaw[name] or 0)+yaw)
+					end
+				end
+				self.turning = true							 
+			elseif self.old_yaw == yaw then
+				-- train is no longer turning
+				self.turning = false
+			end
+			
+			if self.object.set_rotation then
+                local pitch = math.atan2(vdir.y, math.hypot(vdir.x, vdir.z))
+                if data.wagon_flipped then
+                    pitch = -pitch
+                end
+                self.object:set_rotation({x=pitch, y=yaw, z=0})
+            else
+                self.object:setyaw(yaw)
+            end
+			
+			if self.update_animation then
+				self:update_animation(train.velocity, self.old_velocity)
+			end
+			if self.custom_on_velocity_change then
+				self:custom_on_velocity_change(train.velocity, self.old_velocity or 0, dtime)
+			end
+			-- remove discouple object, because it will be in a wrong location
+			if not updatepct_timer_elapsed and self.discouple then
+				self.discouple.object:remove()
+			end
+		end
+		
+		
+		self.old_velocity_vector=velocityvec
+		self.old_velocity = train.velocity
+		self.old_acceleration_vector=accelerationvec
+		self.old_yaw=yaw
+		atprintbm("wagon step", t)
+	end)
+end
+
+function wagon:on_rightclick(clicker)
+	return advtrains.pcall(function()
+		if not self:ensure_init() then return end
+		if not clicker or not clicker:is_player() then
+			return
+		end
+		
+		local data = advtrains.wagons[self.id]
+		
+		local pname=clicker:get_player_name()
+		local no=self:get_seatno(pname)
+		if no then
+			if self.seat_groups then
+				local poss={}
+				local sgr=self.seats[no].group
+				for _,access in ipairs(self.seat_groups[sgr].access_to) do
+					if self:check_seat_group_access(pname, access) then
+						poss[#poss+1]={name=self.seat_groups[access].name, key="sgr_"..access}
+					end
+				end
+				if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+					poss[#poss+1]={name=attrans("Show Inventory"), key="inv"}
+				end
+				if self.seat_groups[sgr].driving_ctrl_access and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+					poss[#poss+1]={name=attrans("Onboard Computer"), key="bordcom"}
+				end
+				if data.owner==pname then
+					poss[#poss+1]={name=attrans("Wagon properties"), key="prop"}
+				end
+				if not self.seat_groups[sgr].require_doors_open or self:train().door_open~=0 then
+					poss[#poss+1]={name=attrans("Get off"), key="off"}
+				else
+					if clicker:get_player_control().sneak then
+						poss[#poss+1]={name=attrans("Get off (forced)"), key="off"}
+					else
+						poss[#poss+1]={name=attrans("(Doors closed)"), key="dcwarn"}
+					end
+				end
+				if #poss==0 then
+					--can't do anything.
+				elseif #poss==1 then
+					self:seating_from_key_helper(pname, {[poss[1].key]=true}, no)
+				else
+					local form = "size[5,"..1+(#poss).."]"
+					for pos,ent in ipairs(poss) do
+						form = form .. "button_exit[0.5,"..(pos-0.5)..";4,1;"..ent.key..";"..ent.name.."]"
+					end
+					minetest.show_formspec(pname, "advtrains_seating_"..self.id, form)
+				end
+			else
+				self:get_off(no)
+			end
+		else
+			--do not attach if already on a train
+			if advtrains.player_to_train_mapping[pname] then return end
+			if self.seat_groups then
+				if #self.seats==0 then
+					if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+						minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))
+					end
+					return
+				end
+				
+				local doors_open = self:train().door_open~=0 or clicker:get_player_control().sneak
+				local allow, rsn=false, "Wagon has no seats!"
+				for _,sgr in ipairs(self.assign_to_seat_group) do
+					allow, rsn = self:check_seat_group_access(pname, sgr)
+					if allow then
+						for seatid, seatdef in ipairs(self.seats) do
+							if seatdef.group==sgr then
+								if (not self.seat_groups[sgr].require_doors_open or doors_open) then
+									if not data.seatp[seatid] then
+										self:get_on(clicker, seatid)
+										return
+									else
+										rsn="Wagon is full."
+									end
+								else
+									rsn="Doors are closed! (try holding sneak key!)"
+								end
+							end
+						end
+					end
+				end
+				minetest.chat_send_player(pname, attrans("Can't get on: "..rsn))
+			else
+				self:show_get_on_form(pname)
+			end
+		end
+	end)
+end
+
+function wagon:get_on(clicker, seatno)
+	
+	local data = advtrains.wagons[self.id]
+		
+	if not data.seatp then data.seatp={}end
+	if not self.seatpc then self.seatpc={}end--player controls in driver stands
+	
+	if not self.seats[seatno] then return end
+	local oldno=self:get_seatno(clicker:get_player_name())
+	if oldno then
+		atprint("get_on: clearing oldno",seatno)
+		advtrains.player_to_train_mapping[clicker:get_player_name()]=nil
+		advtrains.clear_driver_hud(clicker:get_player_name())
+		data.seatp[oldno]=nil
+	end
+	if data.seatp[seatno] and data.seatp[seatno]~=clicker:get_player_name() then
+		atprint("get_on: throwing off",data.seatp[seatno],"from seat",seatno)
+		self:get_off(seatno)
+	end
+	atprint("get_on: attaching",clicker:get_player_name())
+	data.seatp[seatno] = clicker:get_player_name()
+	self.seatpc[seatno] = clicker:get_player_control_bits()
+	advtrains.player_to_train_mapping[clicker:get_player_name()]=data.train_id
+	clicker:set_attach(self.object, "", self.seats[seatno].attach_offset, {x=0,y=0,z=0})
+	clicker:set_eye_offset(self.seats[seatno].view_offset, self.seats[seatno].view_offset)
+end
+function wagon:get_off_plr(pname)
+	local no=self:get_seatno(pname)
+	if no then
+		self:get_off(no)
+	end
+end
+function wagon:get_seatno(pname)
+	
+	local data = advtrains.wagons[self.id]
+	
+	for no, cont in pairs(data.seatp) do
+		if cont==pname then
+			return no
+		end
+	end
+	return nil
+end
+function wagon:get_off(seatno)
+	
+	local data = advtrains.wagons[self.id]
+	
+	if not data.seatp[seatno] then return end
+	local pname = data.seatp[seatno]
+	local clicker = minetest.get_player_by_name(pname)
+	advtrains.player_to_train_mapping[pname]=nil
+	advtrains.clear_driver_hud(pname)
+	data.seatp[seatno]=nil
+	self.seatpc[seatno]=nil
+	if clicker then
+		atprint("get_off: detaching",clicker:get_player_name())
+		clicker:set_detach()
+		clicker:set_eye_offset({x=0,y=0,z=0}, {x=0,y=0,z=0})
+		local train=self:train()
+		--code as in step - automatic get on
+		if self.door_entry and train.door_open and train.door_open~=0 and train.velocity==0 and train.index and train.path then
+			local index = advtrains.path_get_index_by_offset(train, train.index, -data.pos_in_train)
+			for i, ino in ipairs(self.door_entry) do
+				--atdebug("using door-based",i,ino)
+				local fct=data.wagon_flipped and -1 or 1
+				local aci = advtrains.path_get_index_by_offset(train, index, ino*fct)
+				local ix1, ix2 = advtrains.path_get_adjacent(train, aci)
+				local d = train.door_open
+				if self.wagon_width then
+					d = d * math.floor(self.wagon_width/2)
+				end
+				-- the two wanted positions are ix1 and ix2 + (2nd-1st rotated by 90deg)
+				-- (x z) rotated by 90deg is (-z x)  (http://stackoverflow.com/a/4780141)
+				local add = { x = (ix2.z-ix1.z)*d, y = 0, z = (ix1.x-ix2.x)*d }
+				local oadd = { x = (ix2.z-ix1.z)*(d+train.door_open), y = 1, z = (ix1.x-ix2.x)*(d+train.door_open)}
+				local platpos=vector.round(vector.add(ix1, add))
+				local offpos=vector.round(vector.add(ix1, oadd))
+				
+				--atdebug("platpos:", platpos, "offpos:", offpos)
+				if minetest.get_item_group(minetest.get_node(platpos).name, "platform")>0 then
+					minetest.after(GETOFF_TP_DELAY, function() clicker:setpos(offpos) end)
+					--atdebug("tp",offpos)
+					return
+				end
+				--atdebug("nope")
+			end
+		end
+		--if not door_entry, or paths missing, fall back to old method
+		--atdebug("using fallback")
+		local objpos=advtrains.round_vector_floor_y(self.object:getpos())
+		local yaw=self.object:getyaw()
+		local isx=(yaw < math.pi/4) or (yaw > 3*math.pi/4 and yaw < 5*math.pi/4) or (yaw > 7*math.pi/4)
+		local offp
+		--abuse helper function
+		for _,r in ipairs({-1, 1}) do
+			--atdebug("offset",r)
+			local p=vector.add({x=isx and r or 0, y=0, z=not isx and r or 0}, objpos)
+			offp=vector.add({x=isx and r*2 or 0, y=1, z=not isx and r*2 or 0}, objpos)
+			--atdebug("platpos:", p, "offpos:", offp)
+			if minetest.get_item_group(minetest.get_node(p).name, "platform")>0 then
+				minetest.after(GETOFF_TP_DELAY, function() clicker:setpos(offp) end)
+				--atdebug("tp",offp)
+				return
+			end
+		end
+		--atdebug("nope")
+		
+	end
+end
+function wagon:show_get_on_form(pname)
+	if not self.initialized then return end
+	
+	local data = advtrains.wagons[self.id]
+	if #self.seats==0 then
+		if self.has_inventory and self.get_inventory_formspec and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+			minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))
+		end
+		return
+	end
+	local form, comma="size[5,8]label[0.5,0.5;"..attrans("Select seat:").."]textlist[0.5,1;4,6;seat;", ""
+	for seatno, seattbl in ipairs(self.seats) do
+		local addtext, colorcode="", ""
+		if data.seatp and data.seatp[seatno] then
+			colorcode="#FF0000"
+			addtext=" ("..data.seatp[seatno]..")"
+		end
+		form=form..comma..colorcode..seattbl.name..addtext
+		comma=","
+	end
+	form=form..";0,false]"
+	if self.has_inventory and self.get_inventory_formspec then
+		form=form.."button_exit[1,7;3,1;inv;"..attrans("Show Inventory").."]"
+	end
+	minetest.show_formspec(pname, "advtrains_geton_"..self.id, form)
+end
+function wagon:show_wagon_properties(pname)
+	--[[
+	fields: 
+	field: driving/couple whitelist
+	button: save
+	]]
+	local data = advtrains.wagons[self.id]
+	local form="size[5,5]"
+	form = form .. "field[0.5,1;4.5,1;whitelist;Allow these players to access your wagon:;"..minetest.formspec_escape(data.whitelist or "").."]"
+	form = form .. "field[0.5,2;4.5,1;roadnumber;Wagon road number:;"..minetest.formspec_escape(data.roadnumber or "").."]"
+	local fc = ""
+	if data.fc then
+		fc = table.concat(data.fc, "!")
+	end
+	form = form .. "field[0.5,3;4.5,1;fc;Freight Code:;"..fc.."]"
+	if data.fc then
+		if not data.fcind then data.fcind = 1 end
+		if data.fcind > 1 then
+			form=form.."button[0.5,3.5;1,1;fcp;prev FC]"
+		end
+		form=form.."label[1.5,3.5;Current FC:]"
+
+		local cur = data.fc[data.fcind] or ""
+		form=form.."label[1.5,3.75;"..minetest.formspec_escape(cur).."]"
+		form=form.."button[3.5,3.5;1,1;fcn;next FC]"
+	end
+	form=form.."button_exit[0.5,4.5;4,1;save;"..attrans("Save wagon properties").."]"
+	minetest.show_formspec(pname, "advtrains_prop_"..self.id, form)
+end
+
+--BordCom
+local function checkcouple(ent)
+	if not ent or not ent:getyaw() then
+		return nil
+	end
+	local le = ent:get_luaentity()
+	if not le or not le.is_couple then
+		return nil
+	end
+	return le
+end
+local function checklock(pname, own1, own2, wl1, wl2)
+	return advtrains.check_driving_couple_protection(pname, own1, wl1)
+		or advtrains.check_driving_couple_protection(pname, own2, wl2)
+end
+
+local function split(str, sep)
+   local fields = {}
+   local pattern = string.format("([^%s]+)", sep)
+   str:gsub(pattern, function(c) fields[#fields+1] = c end)
+   return fields
+end
+
+function wagon.set_fc(data, fcstr)
+	data.fc = split(fcstr, "!")
+	if not data.fcind then
+		data.fcind = 1
+	elseif data.fcind > #data.fc then
+		data.fcind = #data.fc
+	end	
+end
+
+function wagon.prev_fc(data)
+	if data.fcind > 1 then
+		data.fcind = data.fcind -1
+	end
+	if data.fcind == 1 and data.fcrev then
+		data.fcrev = nil
+	end
+end
+
+function wagon.next_fc(data)
+	if not data.fc then return end
+	if data.fcrev then
+		wagon.prev_fc(data)
+		return
+	end
+	if data.fcind < #data.fc then
+		data.fcind = data.fcind + 1
+	else
+		data.fcind = 1
+	end
+	if data.fcind == #data.fc and data.fc[data.fcind] == "?" then
+		data.fcrev = true
+		wagon.prev_fc(data)
+		return			
+	end
+end
+
+function advtrains.get_cur_fc(data)
+	if not ( data.fc and data.fcind ) then
+		return ""
+	end
+	return data.fc[data.fcind] or ""
+end
+
+function advtrains.step_fc(data)
+	wagon.next_fc(data)
+end
+
+
+
+
+
+function wagon:show_bordcom(pname)
+	if not self:train() then return end
+	local train = self:train()
+	local data = advtrains.wagons[self.id]
+	
+	local form = "size[11,9]label[0.5,0;AdvTrains Boardcom v0.1]"
+	form=form.."textarea[0.5,1.5;7,1;text_outside;"..attrans("Text displayed outside on train")..";"..(minetest.formspec_escape(train.text_outside or "")).."]"
+	form=form.."textarea[0.5,3;7,1;text_inside;"..attrans("Text displayed inside train")..";"..(minetest.formspec_escape(train.text_inside or "")).."]"
+	form=form.."field[7.5,1.75;3,1;line;"..attrans("Line")..";"..(minetest.formspec_escape(train.line or "")).."]"
+	form=form.."field[7.5,3.25;3,1;routingcode;"..attrans("Routingcode")..";"..(minetest.formspec_escape(train.routingcode or "")).."]"
+	--row 5 : train overview and autocoupling
+	if train.velocity==0 then
+		form=form.."label[0.5,4;Train overview /coupling control:]"
+		linhei=5
+		local pre_own, pre_wl, owns_any = nil, nil, minetest.check_player_privs(pname, "train_admin")
+		for i, tpid in ipairs(train.trainparts) do
+			local ent = advtrains.wagons[tpid]
+			if ent then
+				local roadnumber = ent.roadnumber or ""
+				form = form .. string.format("button[%d,%d;%d,%d;%s;%s]", i, linhei, 1, 0.2, "wgprp"..i, roadnumber)
+				local ename = ent.type
+				form = form .. "item_image["..i..","..(linhei+0.5)..";1,1;"..ename.."]"
+				if i~=1 then
+					if checklock(pname, ent.owner, pre_own, ent.whitelist, pre_wl) then
+						form = form .. "image_button["..(i-0.5)..","..(linhei+1.5)..";1,1;advtrains_discouple.png;dcpl_"..i..";]"
+					end
+				end
+				if i == data.pos_in_trainparts then
+					form = form .. "box["..(i-0.1)..","..(linhei+0.4)..";1,1;green]"
+				end
+				pre_own = ent.owner
+				pre_wl = ent.whitelist
+				owns_any = owns_any or (not ent.owner or ent.owner==pname)
+			end
+		end
+		
+		if train.movedir==1 then
+			form = form .. "label["..(#train.trainparts+1)..","..(linhei)..";-->]"
+		else
+			form = form .. "label[0.5,"..(linhei)..";<--]"
+		end
+		--check cpl_eid_front and _back of train
+		local couple_front = checkcouple(train.cpl_front)
+		local couple_back = checkcouple(train.cpl_back)
+		if couple_front then
+			form = form .. "image_button[0.5,"..(linhei+1)..";1,1;advtrains_couple.png;cpl_f;]"
+		end
+		if couple_back then
+			form = form .. "image_button["..(#train.trainparts+0.5)..","..(linhei+1)..";1,1;advtrains_couple.png;cpl_b;]"
+		end
+		
+	else
+		form=form.."label[0.5,4.5;Train overview / coupling control is only shown when the train stands.]"
+	end
+	form = form .. "button[0.5,8;3,1;save;Save]"
+	
+	-- Interlocking functionality: If the interlocking module is loaded, you can set the signal aspect
+	-- from inside the train
+	if advtrains.interlocking and train.lzb and #train.lzb.oncoming > 0 then
+		local i=1
+		while train.lzb.oncoming[i] do
+			local oci = train.lzb.oncoming[i]
+			if oci.udata and oci.udata.signal_pos then
+				if advtrains.interlocking.db.get_sigd_for_signal(oci.udata.signal_pos) then
+					form = form .. "button[4.5,8;5,1;ilrs;Remote Routesetting]"
+					break
+				end
+			end
+			i=i+1
+		end
+	end
+	
+	minetest.show_formspec(pname, "advtrains_bordcom_"..self.id, form)
+end
+function wagon:handle_bordcom_fields(pname, formname, fields)
+	local data = advtrains.wagons[self.id]
+	
+	local seatno=self:get_seatno(pname)
+	if not seatno or not self.seat_groups[self.seats[seatno].group].driving_ctrl_access or not advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+		return
+	end
+	local train = self:train()
+	if not train then return end
+	if fields.text_outside then
+		if fields.text_outside~="" then
+			train.text_outside=fields.text_outside
+		else
+			train.text_outside=nil
+		end
+	end
+	if fields.text_inside then
+		if fields.text_inside~="" then
+			train.text_inside=fields.text_inside
+		else
+			train.text_inside=nil
+		end
+	end
+	if fields.line then
+		if fields.line~="" then
+			if fields.line ~= train.line then
+				train.line=fields.line
+				minetest.after(0, advtrains.invalidate_path, train.id)
+			end
+		else
+			train.line=nil
+		end
+	end
+	if fields.routingcode then
+		if fields.routingcode~="" then
+			if fields.routingcode ~= train.routingcode then
+				train.routingcode=fields.routingcode
+				minetest.after(0, advtrains.invalidate_path, train.id)
+			end
+		else
+			train.routingcode=nil
+		end
+	end
+	for i, tpid in ipairs(train.trainparts) do
+		if fields["dcpl_"..i] then
+			advtrains.safe_decouple_wagon(tpid, pname)
+		elseif fields["wgprp"..i] then
+			for _,wagon in pairs(minetest.luaentities) do
+				if wagon.is_wagon and wagon.initialized and wagon.id==tpid and data.owner==pname then
+					wagon:show_wagon_properties(pname)
+					return
+				end
+			end
+		end
+	end
+	--check cpl_eid_front and _back of train
+	local couple_front = checkcouple(train.cpl_front)
+	local couple_back = checkcouple(train.cpl_back)
+	
+	if fields.cpl_f and couple_front then
+		couple_front:on_rightclick(pname)
+	end
+	if fields.cpl_b and couple_back then
+		couple_back:on_rightclick(pname)
+	end
+	
+	-- Interlocking functionality: If the interlocking module is loaded, you can set the signal aspect
+	-- from inside the train
+	if fields.ilrs and advtrains.interlocking and train.lzb and #train.lzb.oncoming > 0 then
+		local i=1
+		while train.lzb.oncoming[i] do
+			local oci = train.lzb.oncoming[i]
+			if oci.udata and oci.udata.signal_pos then
+				local sigd = advtrains.interlocking.db.get_sigd_for_signal(oci.udata.signal_pos)
+				if sigd then
+					advtrains.interlocking.show_signalling_form(sigd, pname)
+					return
+				end
+			end
+			i=i+1
+		end
+	end
+	
+	
+	if not fields.quit then
+		self:show_bordcom(pname)
+	end
+end
+
+minetest.register_on_player_receive_fields(function(player, formname, fields)
+	return advtrains.pcall(function()
+		local uid=string.match(formname, "^advtrains_geton_(.+)$")
+		if uid then
+			for _,wagon in pairs(minetest.luaentities) do
+				if wagon.is_wagon and wagon.initialized and wagon.id==uid then
+					local data = advtrains.wagons[wagon.id]
+					if fields.inv then
+						if wagon.has_inventory and wagon.get_inventory_formspec then
+							minetest.show_formspec(player:get_player_name(), "advtrains_inv_"..uid, wagon:get_inventory_formspec(player:get_player_name(), make_inv_name(uid)))
+						end
+					elseif fields.seat then
+						local val=minetest.explode_textlist_event(fields.seat)
+						if val and val.type~="INV" and not data.seatp[player:get_player_name()] then
+						--get on
+							wagon:get_on(player, val.index)
+							--will work with the new close_formspec functionality. close exactly this formspec.
+							minetest.show_formspec(player:get_player_name(), formname, "")
+						end
+					end
+				end
+			end
+		end
+		uid=string.match(formname, "^advtrains_seating_(.+)$")
+		if uid then
+			for _,wagon in pairs(minetest.luaentities) do
+				if wagon.is_wagon and wagon.initialized and wagon.id==uid then
+					local pname=player:get_player_name()
+					local no=wagon:get_seatno(pname)
+					if no then
+						if wagon.seat_groups then
+							wagon:seating_from_key_helper(pname, fields, no)
+						end
+					end
+				end
+			end
+		end
+		uid=string.match(formname, "^advtrains_prop_(.+)$")
+		if uid then
+			local pname=player:get_player_name()
+			local data = advtrains.wagons[uid]
+			if pname~=data.owner and not minetest.check_player_privs(pname, {train_admin = true}) then
+				return true
+			end
+			if fields.save or not fields.quit then
+				if fields.whitelist then
+					data.whitelist = fields.whitelist
+				end
+				if fields.roadnumber then
+					data.roadnumber = fields.roadnumber
+				end
+				if fields.fc then
+					wagon.set_fc(data, fields.fc)
+				end
+				if fields.fcp then
+					wagon.prev_fc(data)
+					wagon.show_wagon_properties({id=uid}, pname)
+				end
+				if fields.fcn then
+					advtrains.step_fc(data)
+					wagon.show_wagon_properties({id=uid}, pname)
+				end
+			end
+		end
+		uid=string.match(formname, "^advtrains_bordcom_(.+)$")
+		if uid then
+			for _,wagon in pairs(minetest.luaentities) do
+				if wagon.is_wagon and wagon.initialized and wagon.id==uid then
+					wagon:handle_bordcom_fields(player:get_player_name(), formname, fields)
+				end
+			end
+		end
+		uid=string.match(formname, "^advtrains_inv_(.+)$")
+		if uid then
+			local pname=player:get_player_name()
+			local data = advtrains.wagons[uid]
+			if fields.prop and data.owner==pname then
+				for _,wagon in pairs(minetest.luaentities) do
+					if wagon.is_wagon and wagon.initialized and wagon.id==uid and data.owner==pname then
+						wagon:show_wagon_properties(pname)
+						--wagon:handle_bordcom_fields(player:get_player_name(), formname, fields)
+					end
+				end
+			end
+		end
+	end)
+end)
+function wagon:seating_from_key_helper(pname, fields, no)
+	local data = advtrains.wagons[self.id]
+	local sgr=self.seats[no].group
+	for _,access in ipairs(self.seat_groups[sgr].access_to) do
+		if fields["sgr_"..access] and self:check_seat_group_access(pname, access) then
+			for seatid, seatdef in ipairs(self.seats) do
+				if seatdef.group==access and not data.seatp[seatid] then
+					self:get_on(minetest.get_player_by_name(pname), seatid)
+					return
+				end
+			end
+		end
+	end
+	if fields.inv and self.has_inventory and self.get_inventory_formspec then
+		minetest.close_formspec(pname, "advtrains_seating_"..self.id)
+		minetest.show_formspec(pname, "advtrains_inv_"..self.id, self:get_inventory_formspec(pname, make_inv_name(self.id)))
+	end
+	if fields.prop and data.owner==pname then
+		minetest.close_formspec(pname, "advtrains_seating_"..self.id)
+		self:show_wagon_properties(pname)
+	end
+	if fields.bordcom and self.seat_groups[sgr].driving_ctrl_access and advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist) then
+		minetest.close_formspec(pname, "advtrains_seating_"..self.id)
+		self:show_bordcom(pname)
+	end
+	if fields.dcwarn then
+		minetest.chat_send_player(pname, attrans("Doors are closed! Use Sneak+rightclick to ignore the closed doors and get off!"))
+	end
+	if fields.off then
+		self:get_off(no)
+	end
+end
+function wagon:check_seat_group_access(pname, sgr)
+	local data = advtrains.wagons[self.id]
+	if self.seat_groups[sgr].driving_ctrl_access and not (advtrains.check_driving_couple_protection(pname, data.owner, data.whitelist)) then
+		return false, "Not allowed to access a driver stand!"
+	end
+	if self.seat_groups[sgr].driving_ctrl_access then
+		advtrains.log("Drive", pname, self.object:getpos(), self:train().text_outside)
+	end
+	return true
+end
+function wagon:reattach_all()
+	local data = advtrains.wagons[self.id]
+	if not data.seatp then data.seatp={} end
+	for seatno, pname in pairs(data.seatp) do
+		local p=minetest.get_player_by_name(pname)
+		if p then
+			self:get_on(p ,seatno)
+		end
+	end
+end
+
+local function check_twagon_owner(train, b_first, pname)
+	local wtp = b_first and 1 or #train.trainparts
+	local wid = train.trainparts[wtp]
+	local wdata = advtrains.wagons[wid]
+	if wdata then
+		return advtrains.check_driving_couple_protection(pname, wdata.owner, wdata.whitelist)
+	end
+	return false
+end
+
+function advtrains.safe_couple_trains(id1, id2, t1f, t2f, pname, try_run,v1,v2)
+	
+	if pname and not minetest.check_player_privs(pname, "train_operator") then
+		minetest.chat_send_player(pname, "Missing train_operator privilege")
+		return false
+	end
+	
+	local train1=advtrains.trains[id1]
+	local train2=advtrains.trains[id2]
+	
+	if not advtrains.train_ensure_init(id1, train1)
+		or not advtrains.train_ensure_init(id2, train2) then
+		return false
+	end
+	local wck_t1, wck_t2
+	if pname then
+		wck_t1 = check_twagon_owner(train1, t1f, pname)
+		wck_t2 = check_twagon_owner(train2, t2f, pname)
+	end
+	if (wck_t1 or wck_t2) or not pname then
+		if not v1 then
+			v1 = 0
+		end
+		if not v2 then
+			v2 = 0
+		end
+		if try_run then
+			return true
+		end
+		if t1f then
+			if t2f then
+				v1 = -v1
+				advtrains.invert_train(id1)
+				advtrains.do_connect_trains(id1, id2, v1+v2)
+			else
+				advtrains.do_connect_trains(id2, id1, v1+v2)
+			end
+		else
+			if t2f then
+				advtrains.do_connect_trains(id1, id2, v1+v2)
+			else
+				v2 = -v2
+				advtrains.invert_train(id2)
+				advtrains.do_connect_trains(id1, id2, v1+v2)
+			end
+		end
+		return true
+	else
+		minetest.chat_send_player(pname, "You must be authorized for at least one wagon.")
+		return false
+	end
+end
+
+
+function advtrains.safe_decouple_wagon(w_id, pname, try_run)
+	if not minetest.check_player_privs(pname, "train_operator") then
+		minetest.chat_send_player(pname, "Missing train_operator privilege")
+		return false
+	end
+	local data = advtrains.wagons[w_id]
+	
+	local dpt = data.pos_in_trainparts
+	if not dpt or dpt <= 1 then
+		return false
+	end
+	local train = advtrains.trains[data.train_id]
+	local owid = train.trainparts[dpt-1]
+	local owdata = advtrains.wagons[owid]
+	
+	if not owdata then
+		return
+	end
+	
+	if not checklock(pname, data.owner, owdata.owner, data.whitelist, owdata.whitelist) then
+		minetest.chat_send_player(pname, "Not allowed to do this.")
+		return false
+	end
+	
+	if try_run then
+		return true
+	end
+	
+	advtrains.log("Discouple", pname, train.last_pos, train.text_outside)
+	advtrains.split_train_at_wagon(w_id)
+	return true
+end
+
+
+
+function advtrains.get_wagon_prototype(data)
+	local wt = data.type
+	if not wt then
+		-- LEGACY: Field was called "entity_name" in previous versions
+		wt = data.entity_name
+		data.type = data.entity_name
+		data.entity_name = nil
+	end
+	if not wt or not advtrains.wagon_prototypes[wt] then
+		atwarn("Unable to load wagon type",wt,", using placeholder")
+		wt="advtrains:wagon_placeholder"
+	end
+	return wt, advtrains.wagon_prototypes[wt]
+end
+
+function advtrains.standard_inventory_formspec(self, pname, invname)
+	--[[minetest.chat_send_player(pname, string.format("self=%s, pname=%s, invname=%s", self, pname, invname))
+	for k,v in pairs(self) do
+		minetest.chat_send_player(pname, string.format("%s=%s", k,v))
+	end
+	minetest.chat_send_player(pname, string.format("***%s***", self.object:get_pos()))--]]
+	local data = advtrains.wagons[self.id]
+	local r = "size[8,11]"..
+			"list["..invname..";box;0,0;8,3;]"
+	if data.owner==pname then
+		r = r .. "button_exit[0,9;4,1;prop;"..attrans("Wagon properties").."]"
+	end
+	r = r .. "list[current_player;main;0,5;8,4;]"..
+			"listring[]"
+	return r
+end
+
+function advtrains.register_wagon(sysname_p, prototype, desc, inv_img, nincreative)
+	local sysname = sysname_p
+	if not string.match(sysname, ":") then
+		sysname = "advtrains:"..sysname_p
+	end
+	setmetatable(prototype, {__index=wagon})
+	minetest.register_entity(":"..sysname,prototype)
+	advtrains.wagon_prototypes[sysname] = prototype
+	
+	minetest.register_craftitem(":"..sysname, {
+		description = desc,
+		inventory_image = inv_img,
+		wield_image = inv_img,
+		stack_max = 1,
+		
+		groups = { not_in_creative_inventory = nincreative and 1 or 0},
+		
+		on_place = function(itemstack, placer, pointed_thing)
+			return advtrains.pcall(function()
+				if not pointed_thing.type == "node" then
+					return
+				end
+				local pname = placer:get_player_name()
+
+				local node=minetest.get_node_or_nil(pointed_thing.under)
+				if not node then atprint("[advtrains]Ignore at placer position") return itemstack end
+				local nodename=node.name
+				if(not advtrains.is_track_and_drives_on(nodename, prototype.drives_on)) then
+					atprint("no track here, not placing.")
+					return itemstack
+				end
+				if not minetest.check_player_privs(placer, {train_operator = true }) then
+					minetest.chat_send_player(pname, "You don't have the train_operator privilege.")
+					return itemstack
+				end
+				if not minetest.check_player_privs(placer, {train_admin = true }) and minetest.is_protected(pointed_thing.under, placer:get_player_name()) then
+					return itemstack
+				end
+				local tconns=advtrains.get_track_connections(node.name, node.param2)
+				local yaw = placer:get_look_horizontal()
+				local plconnid = advtrains.yawToClosestConn(yaw, tconns)
+				
+				local prevpos = advtrains.get_adjacent_rail(pointed_thing.under, tconns, plconnid, prototype.drives_on)
+				if not prevpos then
+					minetest.chat_send_player(pname, "The track you are trying to place the wagon on is not long enough!")
+					return
+				end
+				
+				local wid = advtrains.create_wagon(sysname, pname)
+				
+				local id=advtrains.create_new_train_at(pointed_thing.under, plconnid, 0, {wid})
+				
+				if not advtrains.is_creative(pname) then
+					itemstack:take_item()
+				end
+				return itemstack
+				
+			end)
+		end,
+	})
+end
+
+-- Placeholder wagon. Will be spawned whenever a mod is missing
+advtrains.register_wagon("advtrains:wagon_placeholder", {
+	visual="sprite",
+	textures = {"advtrains_wagon_placeholder.png"},
+	collisionbox = {-0.3,-0.3,-0.3, 0.3,0.3,0.3},
+	visual_size = {x=0.7, y=0.7},
+	initial_sprite_basepos = {x=0, y=0},
+	drives_on = advtrains.all_tracktypes,
+	max_speed = 5,
+	seats = {
+	},
+	seat_groups = {
+	},
+	assign_to_seat_group = {},
+	wagon_span=1,
+	drops={},
+}, "Wagon placeholder", "advtrains_wagon_placeholder.png", true)
+