There's not been much activity here recently, but things have been moving behind the scenes. I've mostly been trying to work out how to improve the visuals for my planets. I was just using OpenGL to display them, and I wrote last time about wondering whether to change to a less low-level approach that might make it easier to get a few nice visual effects in. (I was particularly missing the fake 3D effect of my old maps.) After a lot of time alternating between digging deeper into OpenGL and trying alternatives, I decided to use raylib, which is not an engine so much as a library that keeps things pretty low-level, but without quite as much fuss as doing everything in OpenGL directly. Also it's easy to use ImGui with it, and I wasn't going to redo all the GUI at this stage.
There's still quite a lot of getting one's hands dirty with this. I've spent a lot of time tinkering with shaders, and have managed to generate some fairly simple effects, but I'm quite pleased with them:
Getting the normal map to work properly was very fiddly. For some reason I don't understand (a glitch in my cubesphere object, or a glitch in my shader?) the shadows on the top and bottom faces of the cubesphere vary incorrectly across the faces, even when the normal map is definitely correct. So I had to mess about with my normal map creating routine to vary them in the opposite way, to counteract this effect. It's still not perfect, but it looks mostly OK, so I'm sticking with it for now. It's certainly nice to see shading on my mountains again (even though, at this scale, it's probably too exaggerated).
Next I need to think about how to improve my shader - ideally by adding some basic atmospheric effects, as well as clouds, if possible. And then I'll need to think about how to integrate the regional map level into this system, which is where things will get tricky.