The easiest way to check for daylight

[Wishbone]

Okay, doing a new scenario challenge with Lua helpers. Want to check if targets are illuminated by sun (that is, I have global coords of the Sun, Earth and geodesic (lat/lon) coords of the site to check). From what I know from old books, I have to convert global coords to geocentric and then to topocentric cartesian and then to polar topocentric, and compare elevation with -50/60*RAD. Is there a shortcut in Orbiter API or should I do all the matrix stuff by myself? If the latter, would anyone please hint at any formulae that may help (dimly recall I would need local sidereal time).

TIA

 

[orb]

Maybe this post can help you. Though it's C++.

 

[Wishbone]

That's exactly what was needed. Many many thanks :tiphat:

---------- Post added at 09:16 PM ---------- Previous post was at 05:02 PM ----------

Implemented in Lua here: http://www.orbiter-forum.com/showthread.php?p=206675