When the from and to points are not on the enroute structure, check the initial and final legs for large turns (more than 90-degrees) from the overall route course. If found, kill the leg, to generate more natural route and avoid very sharp turns in the terminal area.
Cache the parsed navigation and airport data in a binary file to reduce
startup times and memory consumption (since only referenced FGPositioned
elements are held in memory).
Data will be reimported when the mod-time of any input file is changed.
If a global file is changed (nav.dat, awy.dat, apt.dat, etc), the cache
will be completely rebuilt, which takes approximately 30 seconds on
moderate hardware. (Future work may reduce this).