by toprob » Fri Nov 24, 2006 10:16 am
Once you understand the LODs, you'll know why the tiles seems to duck and dive all over the place. I'll try a quick explanation, but then I'll show you how you don't have to bother with any of this.
LOD means level of detail, and has a couple of meaning in FS. This is just one on 'em...
All the FS world is divided up into LODs. Each LOD is a square, and each LOD is then divided into 4 quadrants, each quadrant becoming a new LOD. And so on. After you have divided up LODs 13 times, you come to LOD 13, which is a square approx 1.2 kilometres on each side, which is what we are looking at in the Annotator.
The file names for these tiles -- mostly a 15 digit number -- is the actual location of the tile in this LOD world. You'll notice that the numbers range from 0 to 3, and these represent the quadrant -- zero being upper left, and 3 being lower right. The first number in this 15 digit set is LOD zero, which represents the world. (Not entirely accurate, but I have limited space here:)
You could pinpoint the position of a LOD fairly accurately on a map just with a ruler, if you were nerdy enough.
If you are walking along in the FS world, say heading due east, you may start in the bottom left quadrant of a LOD. You'll cross into the bottom right quadrant, then the bottom left of the NEXT LOD etc. Looking at the names of the tiles you've crossed, the last two numbers of each might be 12 - 13 - 22 - 23.
I've seen a diagram somewhere which shows this well, if I could find it then I wouldn't be floundering here...
Anyway, you could use this understanding of LODs to track down a specific spot in the sim, but you're better off using a handy tool. I use TCalc2004, by Richard Ludowise, (search for it) and this uses FDSConnection to display data from the sim. As you fly over an area in the sim TCalc2004 will update with your position etc, including the actual tile name you are flying over.
It also gives the names of the surrounding tiles as well, so I just copy/paste into Annotator to open a specific tile.