Monday evening
Switched to PyOpenGL. It is not as convenient as ModernGL but there is documentation... On StackOverflow and Reddit...
I know it is possible to waste a lot of time creating worlds. I decided to not make a planet spherical at least.
I'm drawing primarily with glDrawArrays. Checked its limits. After 100 calls per frame FPS drops below 60. And after 1000 my computer starts making strange sounds.
My code is 700 lines of mess.