It is also a way of creating a geographically accurate Trainz map. Lets say you have a map source such as Google map from which you can determine the exact geographic longitude and latitude coordinates of any point. Once you place the World Origin marker at your starting point and assign it the correct coordinates from Google Map, you can then place any number Trig Stations to mark other points on the map you want to build to and as you move them about they will give you their coordinates, which you can correlate to the coordinates on the Google map to which you are modelling. A little laborious, but it would work. I suspect this is the reason "Surveyor" is called Surveyor.
