src/AIModel/AIAircraft.cxx src/ATC/AILocalTraffic.cxx
src/FDM/flight.cxx src/FDM/flight.hxx src/FDM/groundcache.cxx
src/FDM/groundcache.hxx src/Main/fg_init.cxx src/Main/main.cxx
src/Scenery/hitlist.cxx src/Scenery/hitlist.hxx
src/Scenery/scenery.cxx src/Scenery/scenery.hxx
Make use of the attached SGMaterial reference userdata on scenegraph
leafs. Make the SGMaterial pointer available to the ground query
routines.