I am developing a Minecraft clone in C++/OpenGL on Linux. I am using SDL2 for creating a window and an OpenGL context.
Everything seems to be working - except not all the time. Sometimes when I run my game, it works. The next time I run it, it won't render anything (just the clear color).
You can view the source code of the game on GitHub here: http://github.com/brettmw/cubed
Screenshot of when it's functioning correctly:
And when it's not: