I’m quite pleased with this. It took about six hours in total to create including the time to create the graphics. Running in Hyper-V under Ubuntu 20.04, it draws a screenful of graphics in about 65 microseconds.
I took the hexagon drawing code from the AboutEmpire.zip code on GitHub and modernised it for SDL2. The Empire code uses Surfaces from SDL1 while this uses Textures from SDL2.
There are nine hexagons with all but the dark one having an internal border.
I think the orange and salmon hex look a bit too close, so I’ll change one of them.