X-Plane scenery is organized into packages. A scenery package is a folder that contains files in a specific layout.
Scenery packages are made up of four kinds of files:
A scenery package may contain any of these types of files, but none of these types are required per se.
Generally a folder from the layouts shown may be omitted if it is empty.
A custom scenery package can have any name you choose.
The X-Plane world is divided into tiles. Each tile is bounded on each side by a latitude and longitude line. Tiles are named by their southwest corner - positive numbers for the northern hemisphere and east of the prime meridien and negative numbers for the southern hemisphere and west of the prime meridien. For example:
Tile files come in two formats:
Tile files are organized into folders that are organized by 10-degree latitude and longitude lines. Each folder has at most 100 tile files, but does not need to contain all 100 files. The scenery package does not have to have every tile folder. Some examples:
Scenery can be for the planet Earth or Mars; tile files for Earth go in the Earth nav data folder; tiles files for Mars go in the Mars nav data folder. The full package might look like this:
My Great Scenery Earth nav data +40-080 +42-072.dsf +42-071.dsf +40+010 +46+011.env