Nasal: scenery availability check

[Hooray]

Subject: Tutorials/Missions/Adventures: requests for features

The airfield for this competition is LECD-La Cerdanya (http://www.aerodromlacerdanya.cat), a small airfield in the Pyrinees close to the French-Spanish border. LECD has a runway 07/25 of 1150m. The competition will be held in runway 25.
RL

A while ago, there used to be a feature/patch that would write scenery/tile availability to the property tree - these days, this no longer seems to be the case, but we may need to add some simple helper function to check if a required scenery tile is available/installed or not (e.g. via io.nas and opening a BTG file), so that people don't try to run missions that require certain scenery that isn't installed.

[psadro_gm]

Be aware that .BTG files will be moving into a LOD hierarchy. If such a 'is scenery available' feature is written, please consider that at the lowest level of detail - we'll have the world sphere.

[Hooray]

ok, thanks for the heads-up - so I guess then it would be better to directly use the tile manager logic and add a fgSetBool() there to end up with is "tile-is-available" property ?
Otherwise, we may replicate lot of path-finding logic in Nasal space probably ?

[psadro_gm]

It's hard to say, as we're looking at incomplete code right now. That said, it is the tile manager's responsibility to know whether or not a tile is loaded. I think it's safe to say this would be the best place to have a check tile loaded interface.