Access to towns.lua please?

[cfrag]

Every map (well, currently every map except Sinai) comes with a comprehensive Lua dict that contains the location and name of every named village, town or city on the map, e.g. 

["BATUMI"] = { latitude = 41.654059, longitude = 41.655372, display_name = _("BATUMI")},

For example, for Caucasus, the dict contains some 1760 entries. That file is called 'towns.lua' and is buried deep within the DCS structure for every map. Sadly, that table is not accessible from within the scripting environment. 

I would very much like it if the "towns" table were made available to mission scripting, so mission creators can use this information for a *much* better player experience. 

For example: instead of telling players that a pilot was downed at some MGRS or Lat/Lon, the mission could tell players that the player was downed "2km SW of Zugdidi"

Since the information is already present, and likely read when the map is read for the mission, I hope that bridging this table for the scripting environment is not difficult

Edited July 5, 2024 by cfrag

[HC_Official]

+1 to this idea

[ops]

Hello,

here's a piece of code that returns data of interest out of the terrain files that are readable (beacons, towns and radio)

It either works GUI/server env, or in mission env with desanitized MissionScripting.lua (require and package need be available):

-- "Afghanistan", "Caucasus", "Falklands", "Kola", "MarianaIslands", "Nevada", "Normandy", "PersianGulf", "Sinai", "Syria", "TheChannel"
function getTerrainData(terrain)
    local hasBeacons, beacons = pcall(function() loadfile("./Mods/terrains/" .. terrain .. "/beacons.lua")() return beacons end)
    local hasRadio, radio = pcall(function() loadfile("./Mods/terrains/" .. terrain .. "/radio.lua")() return radio end)
    local hasTowns, towns = pcall(function() loadfile("./Mods/terrains/" .. terrain .. "/map/towns.lua")() return towns end)
    result = { beacons = hasBeacons and beacons or nil, radio = hasRadio and radio or nil, towns = hasTowns and towns or nil }
    return result
end

return getTerrainData("Kola")

 

 

[cfrag]

On 7/17/2024 at 3:16 PM, ops said:

here's a piece of code that returns data

Thank you for the code snipped

On 7/17/2024 at 3:16 PM, ops said:

with desanitized MissionScripting.lua

That, unfortunately, is a show stop. I would like to have access to this data from within vanilla mission setup, so anyone can run this mission without having to change their DCS install.

[ops]

On 7/24/2024 at 2:04 PM, cfrag said:

Thank you for the code snipped

That, unfortunately, is a show stop. I would like to have access to this data from within vanilla mission setup, so anyone can run this mission without having to change their DCS install.

you can use net.dostring_in("gui") without desanitizing and with some trickery (dostring in "mission" and a_do_script) funnel results back into the mission env.

but that data changes only on map updates anyway (if at all)

[cfrag]

14 hours ago, ops said:

you can use net.dostring_in("gui") without desanitizing and with some trickery

Now that's some crafty thinking - I like it, thank you!  

Here's a preliminary code snippet that will get you the currently running map's "towns" table into the mission. It seems to work in single-player, and needs some more testing (for example with maps like Sinai that do not have a "towns.lua", and with a sanitized DCS. But it is a giant step forwards.

For those who are wondering: the other dirty little trick (beside net.dostring_in) is to use lua2json to serialize towns, stream it over to the mission environment, and then use json2lua to assemble it back into a table). 

	local theater = env.mission.theatre 
	local path = "./Mods/terrains/" .. theater .. "/map/towns.lua"
	-- assemble command 
	local command = 't = loadfile("' .. path .. '"); if t then t(); return  net.lua2json(towns); else return nil end'
	trigger.action.outText("will run command <" .. command .. ">", 30)
	
	local json = net.dostring_in("gui", command)
	
	if json then 
		towns = net.json2lua(json)
	else 
		trigger.action.outText("no joy", 30)
	end 

 

Edited August 1, 2024 by cfrag

[cfrag]

Confirmed. This method automatically works with all maps (except, as expected "Sinai" because that map still has no 'towns.lua', shame on you, ORT!) even in fully sanitized DCS. I *still* think it would be better if ED made this table available automatically instead of having the mission jump through hoops like this to gain access. Perhaps @Grimes has some insight into why that table isn't accessible otherwise?

I have amended the script slightly so it can run as a tiny lib that will return you the name of the town closest to a point. For this, the script also compiles map coordinates from the LatLon for quick access.

twn = {}
twn.version = "0.0.0"

function twn.closestTownTo(p)
	if not towns then 
		trigger.action.outText("Towns is undefined", 30)
		return nil 
	end
	local closest = nil 
	local theName = nil 
	local smallest = math.huge
	local x = p.x 
	local z = p.z 
	for name, entry in pairs(towns) do 
		local dx = x - entry.p.x 
		local dz = z - entry.p.z
		local d = dx * dx + dz * dz -- no need to take suqare root 
		if d < smallest then 
			smallest = d 
			closest = entry 
			theName = name 
		end
	end
	return theName, closest, smallest^0.5  
end

function twn.start()
	-- get my theater
	local theater = env.mission.theatre 
	trigger.action.outText("theater is <" .. theater .. ">", 30)
	local path = "./Mods/terrains/" .. theater .. "/map/towns.lua"
	-- assemble command 
	local command = 't = loadfile("' .. path .. '"); if t then t(); return net.lua2json(towns); else return nil end'
	trigger.action.outText("will run command <" .. command .. ">", 30)
	
	local json = net.dostring_in("gui", command)
	
	if json then 
		towns = {}
		traw = net.json2lua(json)
		for name, entry in pairs (traw) do 
			local p = coord.LLtoLO(entry.latitude, entry.longitude,0)
			entry.p = p 
			towns[name] = entry
		end 
		
	else 
		trigger.action.outText("no joy", 30)
	end 
	
end

twn.start()

local theZone = trigger.misc.getZone("test")
local name, entry, dist = twn.closestTownTo(theZone.point)
trigger.action.outText("Zone is closest to <" .. name .. ">, d = <" .. math.floor(dist/100) / 10 .. "km>", 30)

Below find a demo mission that finds the name of the town closest to the Trigger zone named "test"

frigging null

mytown.miz

Edited August 1, 2024 by cfrag

[Grimes]

AFAIK the towns.lua is primarily used by the KA-50's ABRIS and its town search page. The town names that appear on the F10 map are baked in someplace else in the terrain files. There is an open feature request for a scripting function access to town information. 

[cfrag]

8 hours ago, Grimes said:

AFAIK the towns.lua is primarily used by the KA-50's ABRIS and its town search page. The town names that appear on the F10 map are baked in someplace else in the terrain files.

Thank you so much for adding that background information, Grimes!