MeshXP function is to add elevations points to the terrain to further increase elevations precision and a better shaped terrain. This mesh can be used on its own or underneath photorealistic scenery. It use X-Plane 12 default Vectors ie roads, landclass. This is an X-Plane 12 terrain mesh. Coverage: France (included Corsica). No decrease of frame rates. All MeshXP packages are designed to fit into each over to provide continuous coverage.