Heliotrope: a plugin app that tracks the sun
This plugin tracks the sun like the little purple flower it's named after. Once it's installed, it displays the Azimuth and Altitude of the sun as it travels the sky. It's icon changes from a dark-gray color at night to a yellow color during the day. It makes four variables available for computing inside luup code: Azimuth, Altitude, Right Ascension, and Declination. For example luup code can determine if the sun is in such a position that lights need to be turned on or that a shade needs to be drawn.