I've been doing a fair bit of tinkering with the model, focusing on improving the algorithms connected with monthly changes. Seasonal temperatures and rainfall are now more realistic (more or less), and so is river flow. You can also pull up monthly river flow charts alongside those for temperatures and rainfall, to get a better idea of seasonal changes for any point on the globe.
Alongside this, I've removed some bugs with specular maps (rivers now reflect sunlight correctly) and improved the appearance of clouds.
After doing all that, I decided that my planets looked a little lonely floating in the void, so I've added procedurally generated starfields, galactic dust and nebulae, and some bloom effects on the sun, as well as simple lens flares. All of these can be adjusted in the settings. I wrote all the shaders from scratch, as I couldn't find anything quite like what I wanted. This was a pretty tough learning curve, but I'm glad to have managed it and am quite pleased with the final effects.
Here are a few shots showing how it looks now:
All of this means I've more or less run out of things to do before tackling the next big thing, which is adapting the regional map model to the new spherical layout. As I've mentioned before, this is inherently tricky. The ideal solution, if I can manage it, is to generate regional maps on the fly while the globe is displayed, and display them on the globe in the appropriate places as they're generated, if it's zoomed in enough to make it worthwhile. So this would involve keeping a lot of regional maps in memory at the same time, with hopefully a system intelligent enough to generate precisely the ones that are needed, depending on where the user is looking, and deleting the ones that aren't.
That's the plan anyway! If I can't get that to work then I may have to go for a less ambitious system where the regional maps are displayed in a different screen altogether, as with the 2D version.
