Sunrise/Sunset Calculations

• Download demo project - 16.6 KB
• Download source files - 4.4 KB

Introduction

I searched the web for a piece of code that calculates the Sunrise/Sunset based on the Date and a latitude and longitude, but could not find one in C++ that was freely available. People have FreeWare out there, but were unwilling to give out the source as they deemed it to "valuable". So I took it upon myself to convert one of the other freely available pieces of code, and convert it for everyone to use.

I have written the following C++ code. It is based heavily on the JavaScript I obtained directly from the NOAA. I find that many applications may have a use for this information, so feel free to use it to make your own FreeWare tray applications, or any other Utility Programs.

The three main functions are:

CTime GetSunset(double dLat,double dLon,CTime time);
CTime GetSunrise(double dLat,double dLon,CTime time);
CTime GetSolarNoon(double dLon, CTime time);

which take in Latitude and Longitude values as doubles and a CTime with the Date that you want to calculate the SR/SS for. It returns a CTime in UTC.

I have included a non-MFC Tray icon class I have written, with the example. It has the basic functionality to display a tray icon, and can be used in MFC, Win32 and ATL applications. Probably not as good as the newest CSystemTray, but I use it with Win32 to make very small footprint applications!!

I have also added more functionality to the demo, as the way I originally submitted it, it had very little actual functionality. I also added the code so it is converted from UTC as well.

Hope someone finds it useful....

License

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