add small script to create json files for use with lifomapserver

These json files can then be used to help with train routing through
the network

routes.lua

@@ -0,0 +1,131 @@
+-- Small script to generate json files for lifomapserver to use for routing
+
+advtrains = {}
+minetest = {}
+core = minetest
+
+math.hypot = function(a,b) return math.sqrt(a*a + b*b) end
+function attrans(str) return str end
+
+dofile("vector.lua")
+dofile("serialize.lua")
+dofile("helpers.lua")
+
+
+function parse_args(argv) 
+	local i = 1
+	local no_trains = false
+	local datapath, mappath, worldimage
+	while i <= #argv do
+		local a = argv[i]
+		if (a == "-m") or (a == "--map-file") then
+			-- only draw trains – requires specifying an already drawn file
+			i = i+1
+			if not argv[i] then
+				error(("missing filename after `%s'"):format(a))
+			end
+			mappath = argv[i]
+		elseif (a == "-t") or (a == "--no-trains") then
+			-- do not draw trains
+			no_trains = true
+		elseif (a == "-w") or (a == "--world-image") then
+			-- overlay over world image
+			i = i+1
+			if not argv[i] then
+				error(("missing filename after `%s'"):format(a))
+			end
+			worldimage = argv[i]
+		else
+			datapath = a
+		end
+		
+		i = i + 1
+	end
+	return datapath, mappath, no_trains, worldimage
+end
+
+datapath, mappath, no_trains, worldimage = parse_args(arg)
+
+function ars_to_text(arstab)
+	if not arstab then
+		return "{}"
+	end
+	
+	local txt = {}
+	local ln = {}
+	local rc = {}
+	for i, arsent in ipairs(arstab) do
+		local n = ""
+		if arsent.n then
+			n = "!"
+		end
+		if arsent.ln then
+			ln[#ln+1] = '"'..n..arsent.ln..'"'
+		elseif arsent.rc then
+			rc[#ln+1] = '"'..n..arsent.rc..'"'
+		elseif arsent.c then
+			txt[#txt+1] = "#"..arsent.c
+		end
+	end
+
+	return '{"LN": ['..table.concat(ln,',')..'], "RC" : ['..table.concat(rc,",")..']'.. ',"default": '..(arstab.default and "true" or "false").."}\n"
+end
+
+
+local file = io.open(datapath.."advtrains_interlocking_tcbs", "r")
+local tbl = minetest.deserialize(file:read("*a"))
+advtrains.tcbs = tbl
+file:close()
+
+local jsonfile = io.open(datapath.."signals.json", "w")
+
+
+tcbstr = {}
+for k,v in pairs(advtrains.tcbs) do
+	local routes = v[1].routes or {}
+	if v[2].routes then
+		for a,b in ipairs(v[2].routes) do
+			routes[#routes+1] = b
+		end
+	end
+	local pos = k:sub(2,-2)
+	local sp = {}
+	for j in (pos..","):gmatch("([^,]+),") do
+		sp[#sp+1] = j
+	end
+	local sigpos = sp[1]..","..-sp[3].." "
+		
+	local routestr = {}
+	for i,r in pairs(routes) do
+		local pl = sigpos
+
+		local tcbps = {}
+		--		svgfile:write("<circle cx=\""..sp[1].."\" cy=\""..-sp[3].."\" r=\"3\" stroke=\"".."purple".."\" stroke-width=\"1\" fill=\"none\" />")
+		for ind,ps in ipairs(r) do
+			if ps.next then
+				local tcb = ps.next.p
+				--				print(minetest.serialize(ps.next))
+				if tcb and tcb.x then
+					tcbps[#tcbps+1] = tcb.x..","..tcb.y..","..tcb.z
+					pl = pl.." "..tcb.x..","..-tcb.z
+				end
+			end
+		end
+
+		if #tcbps > 0 then
+			routestr[#routestr+1] = '{ "name": "'..r.name..'",\n"endpoint": "'..tcbps[#tcbps]..'",\n"ars": '..ars_to_text(r.ars)..' }'
+		end
+		color = "blue"
+		if r.ars and r.ars.default then
+			color = "green"
+		end
+		if pl~="" then
+		--	svgfile:write("<polyline points=\""..pl.."\" fill=\"none\" stroke=\""..color.."\" />")
+		end
+	end
+	if #routestr > 0 then
+		tcbstr[#tcbstr+1] = '"'..pos..'": { "type" : "Feature", "geometry": { "type": "Point", "coordinates": [ '..sp[1]..","..sp[3]..']}, "properties" : { "pos": "'..pos..'", "routes" : [\n'..table.concat(routestr,",\n").."]}}"
+	end
+end
+jsonfile:write("{"..table.concat(tcbstr,",\n").."}")
+jsonfile:close()