data density example added
data density example added

OSMBuildings/OSMBuildingsClassic,hgarnelo/osmbuildings,hgarnelo/osmbuildings,faegi/osmbuildings,kekscom/osmbuildings,faegi/osmbuildings,faegi/osmbuildings,OSMBuildings/OSMBuildingsClassic,hgarnelo/osmbuildings,kekscom/osmbuildings