Comment Re:True North? (Score 1) 260
My guess, without having any particular knowledge, is that the factory will have some kind of internal grid system (fairly common), and aligning the factory with a compass direction means you can easily convert between internal coordinates and lat/lon GPS coordinates. Of course assuming you aren't converting by hand, it's not really hard to convert even if the factory were not axis-aligned.
Even if it has an internal grid system, I can't come up with a plausible why you'd want to convert from GPS to the internal grid. To be accurate enough to use GPS to locate yourself on the grid... well, unless the grid is good sized (at least 2-3 meters on a side) you simply can't, not in real time anyway. And once the building is closed in, the accuracy will likely degrade even further. Using GPS to establish the grid... well, again the compass heading of the grid is easy to correct for. There's no particular advantage to aligning to any particular compass heading because you can correct in software, and that's already common.