I tried to post a more generic question to meta, but it's my first question, so I didn't have a reputation yet.
The first question I have is whether this is an appropriate place to ask questions about the availability of software "components"--APIs or toolkits for mapping and geographic/geodetic functions.
If this is the appropriate place: I would very much like to find an open source mapping API, using either OpenGL or one of the QT graphics APIs like QPaint--something that draws and labels axes and graticules, scales, etc--if it had geographic entry points (lat, long) so much the better. Map underlays would be wonderful.
I have not been able to find anything despite repeated searches, so have written a good deal of my own, using C++/QT/OpenGL. But I find I am spending as much time on my infrastructure as I am on my application, and I'd like to get out of that situation if possible.
My application is typically real-time plotting of positions of underwater vehicles and associated data.