GetDirection function... Thanks Lyqyd

local vec1 = vector.new(gps.locate(2, false))
turtle.forward()
local vec2 = vector.new(gps.locate(2, false))
turtle.back()
local heading
if vec1 and vec2 then
  local resultVec = vec2 - vec1
  heading = ((resultVec.x + math.abs(resultVec.x) * 2) + (resultVec.z + math.abs(resultVec.z) * 3)) % 4
  --heading now contains a number 0-3 corresponding directly to the minecraft direction codes.
end