In addition to the generic FME feature attributes that FME Workbench adds to all features (see About Feature Attributes), this format adds the format-specific attributes described in this section.
OpenFlight features consist of geometry and attributes. The attribute names are defined in the DEF line and there is a value for each attribute in each OpenFlight feature. There are currently no supported format-specific attributes for the OpenFlight writer. The geometries supported by OpenFlight are limited to polygons, surfaces, and solids.
Geometries with no Z coordinates (2D geometries) will be assigned 0 as their z values.
Level of Detail Support
The OpenFlight writer supports writing out level of detail information. Level of detail (LOD) nodes for a geometry can be written to OpenFlight files by creating a multiple geometry and setting the appropriate _LOD_MIN_RANGE and _LOD_MAX_RANGE traits for each child geometry. These values determine the visibility for each geometry based on distance to the camera in ground units.
External Reference Support
The OpenFlight writer supports writing out a master file containing references to other OpenFlight files within the same folder. A reference to another OpenFlight file can be made by creating a null geometry and setting the openflight_external_ref trait with the name of the file to be included. The reference can be written at any level of the geometry’s hierarchy. If the referenced file is not found in the destination folder, a warning will be issued.