|Landclass is an index file pointing to terrain textures that form the patterns of land-use textures seen on the terrain mesh. It does not include the textures themselves, which already exist in the FS folder structure. Rather, it tells the terrain engine where to display a particular texture in a grid of 1.2 km areas comprising the flight simulator world.
The FSGenesis US National Landclass Project for FSX uses as source data the latest, most highly-refined dataset available to bring the FSX depiction of landuse to the most accurate possible within the confines of the current terrain engine. This product is derived from the 2001 National Land-Cover Database for the United States (NLCD 2001), produced by the Multi-Resolution Land Characterization 2001 (MRLC 2001), a US federal consortium designed to gather an updated pool of nationwide Landsat 5 and 7 imagery to create a second-generation National Land Cover Database.
As in the real-world, this landclass product is a "living" project, meaning that it is in constant evolution. As new, more recent data is discovered, and as local end-user feedback comes in, changes are made and free updates become available.
Below please see a couple of typical examples of the benefits of using FSG US National Landclass Project for FSX: