View difference between Paste ID: GQSS5vx9 and jpKfiEgm

 --[[
 ARC: AR Client
 Uses Plethora overlay glasses and modems to display 3D signage transmitted from local "beacons"
 ]]
 
 local m = peripheral.find "modem"
 local mods = peripheral.wrap "back"
 
 if not m then error "Modem required." end
 if not mods then error "Is this even on a neural interface?" end
 if not mods.canvas3d then error "Overlay glasses required." end
 
 local canv = mods.canvas3d()
 
 local object_channel = 666
 
 m.open(object_channel)
 
 local x, y, z
 
 -- convert position to string for use as table key
 local function serialize_position(p)
 	return string.format("%f,%f,%f", p[1], p[2], p[3])
 end
 
 -- Generate a string representation of a table, for easy comparison. Not really hashing, I guess.
 local function hash_table(x)
 	if type(x) == "table" then
 		local out = ""
 		for k, v in pairs(x) do
 			if type(k) ~= "string" or not k:match "^_" then -- ignore keys beginning with _
 				out = out .. hash_table(k) .. ":" .. hash_table(v) .. ";"
 			end
 		end
 		return out
 	else
 		return tostring(x)
 	end
 end
 
 -- honestly not that elegant, but it works
 -- TODO: do this more efficiently/nicely somehow?
 local function tables_match(x, y)
 	return hash_table(x) == hash_table(y)
 end
 
 local objects = {}
 local timers = {}
 
 local function redraw(object)
 	local frame = object._frame
 	frame.clear()
 end
 
 local function process_object(object)
 	local pos = serialize_position(object.position)
 	if objects[pos] then
 		if not tables_match(object, objects[pos]) then
 			print("redrawing", pos)
 			objects[pos] = object
 			redraw(objects[pos])
 		end
 		local t = os.startTimer(20)
 		timers[t] = pos
 	else
 		print("new object at", pos)
 		if x then
 			local frame =
 		else
 			print("GPS error, cannot create object")
 		end
 	end
 end
 
 local function main_loop()
 	while true do
 		local event, timer, channel, reply_channel, message, distance = os.pullEvent()
 		if event == "modem_message" and channel == object_channel and distance and type(message) == "table" then -- ensure message is from this dimension and otherwise valid
 			for _, object in pairs(msg) do
 				local ok, err = pcall(process_object, object)
 				if not ok then printError(err) end
 			end
 		elseif event == "timer" then
 			local objpos = timers[timer]
 			if objpos then
 				local obj = objects[objpos]
 				if obj then
 					print(objpos, "timed out")
 					obj._frame.remove()
 					objects[objpos] = nil
 				end
 			end
 		end
 	end
 end
 
 -- Request location every second
 local function GPS_loop()
 	while true do
 		x, y, z = gps.locate()
 		sleep(1)
 	end
 end
 
 parallel.waitForAll(GPS_loop, main_loop)