I need a imagine a plane targeting a destination like on screenshot.
Now the destination get out of view.
To help the player to find it I need a pointer towards the target. Maybe somebody have code like this ?

Keep searching the these forums, especially the lite-c forum.
Someone did have a posting about "map directional arrows" or some phrase like
that a while ago, I think they managed to figure something out.
Sorry I cant post a link, but I cant remember what the thread name was.

Needle panel element for arrow display:
http://www.conitec.net/beta/needle.htm

Use vec_to_angle for calculating the directional angle to the target:
http://www.conitec.net/beta/avec_to_angle.htm

Thanks.