hi how does one calculate where the horizon line shoud be? from flight simulators, we know that the horizon goes up, if we go down, and it goes down, if we go up. thanks

Hmm. If you make the approximation that the Earth is flat, then the horizon line is at the same level (apparent height) as your eyes.

Cédric

All you need to know is the radius of the earth, which last year I would have known. Then it''s a case of simple trig to work it out.

I think the angle below the plane with up being a normal, would be given by:

arccos(r/(r+h))

where r is the radius of the earth and h the height of the aircraft.

You would have to go pretty high to see any effect. Also then the horizon would be curved, so drawing it would be harder, but not much of a problem. It''s probably only worth implementing if you get really really high. So unless you can fly into space, I wouldn''t bother.

arccos(r/(r+h)) is correct
it is all here:
http://www-istp.gsfc.nasa.gov/stargaze/Shorizon.htm
thanks





[edited by - carbon14 on August 13, 2003 11:17:01 AM]