If someone can help me with equirectangular projection, I can assist updating this mod to Factorio 2.1.
But I don't have previous experience with this kind of image mapping.
Here are docs;
https://lua-api.factorio.com/latest/types/PlatformBackdrop.html#planet_surface
Sample code to overwrite planet image;
data.raw.planet["nauvis"].platform_surface_render_parameters.platform_backdrop.planet_surface = {
filename = "__valerian-planets__/graphics/nauvis-equirectangular.png",
width = 4096,
height = 2048
}
