Nice blogpost Arno! Let me try to provide some quick answers on the questions that you raised:
There is no slew mode, so I had quite some trouble to view my objects after placing.
Right, that's something we lack. You can move the tower-view around though, by clicking in the scenery, maybe that's slightly better than flying around in the UFO? This does require a little hack though, more info at
our wiki.
When placing the object you need to enter the altitude above MSL. So for one object it took a bit of trial and error to get this right. An option to just place them at terrain altitude would be useful.
The people that maintain our
scenery database have some tools that automatically place thousands of objects at ground level, whenever a new scenery build is initiated (and thus likely changing the elevation, due to more accurate elevation data being used).
I could not find a way to place my objects in their own scenery package, the placement information goes into the same tiles as the global scenery.
As of FlightGear 2.4.0 you can specify more than one scenery directory (
--fg-scenery=path1;path2;path3..., or first page of the launcher/FGRun; click the previous button on the Aircraft Selection page). FlightGear tries to load scenery-tiles from the first(top, in FGRun) directory. If the current tile does not exist there, it moves on to the second directory. This allows (for example NL-2000) to provide scenery addons outside the main FlightGear folder. Pilots can simply give your addon's directories a higher priority.
The placement information needs to go into tile files with a very specific filename. I had to go into FlightGear to find the name for the location of my object, I would find it easier if you could just specify a position of an object.
There's a Perl script ->
https://gitorious.org/fg/flightgear/blobs/next/scripts/perl/scenery/calc-tile.pl I've never used it, but it might work
I couldn't find a way to start FlightGear at a specific latitude and longitude, it seems you can only start at an airport.
If you run FlightGear from commandline (try
--lon=... --lat=...), when using the launcher/FGRun, go to Advanced > Initial position. You'll find the Advanced button on the last page of the launcher.
PS: Welcome to our forum Arno