ActiveGPS

term.clear()
term.setCursorPos(1,1) --Initiate the screen

local homeLoc = {}


print("Do you want to set your home position? Y/N")
local setHome = read()

if setHome == "Y" or setHome == "y" or setHome == "yes" then
  term.clear()
  local h = fs.open(".agpshome", "w")
  local newHome = {}
  local newHome = {gps.locate(1)} --Attempt to locate with gps to make newHome.

  if #newHome < 3 then
    print("GPS Signal Unavailable.")
    print("Please set manually. Input in order: X, Y, Z.") --Read inputs into newHome.
    newHome[1] = read()
    newHome[2] = read()
    newHome[3] = read()
  end

  h.write(textutils.serialize(newHome))
  h.close()
end


if fs.exists(".agpshome") then
  local h = fs.open(".agpshome", "r")

  homeLoc = textutils.unserialize(h.readAll())
  h.close()
end

while true do
  term.clear()
  term.setCursorPos(1,1)
  local loc = {gps.locate(1)} --Attempt to locate with gps, timeout 1 second.
  local sleepTime = 0.5
  if #loc < 3 then
    print("GPS Signal Unavailable.")
    sleepTime = 2
  else
    print("Location:")
    print("X: "..loc[1])
    print("Y: "..loc[2])
    print("Z: "..loc[3])
  end

  if #homeLoc > 1 then
    print("Home Location:")
    print("X: "..homeLoc[1])
    print("Y: "..homeLoc[2])
    print("Z: "..homeLoc[3])

    print("Distances from Home:")
    local homeVector = vector.new(homeLoc[1], homeLoc[2], homeLoc[3])
    local locVector = vector.new(loc[1], loc[2], loc[3])
    local homeDistance = locVector - homeVector --Use vector math to calculate distance
    print("X: "..homeDistance.x)
    print("Y: "..homeDistance.y)
    print("Z: "..homeDistance.z)
  end

  sleep(sleepTime)
end