Best Projection for a Ring World

[Thurlor]

I'm not sure what you mean by wrapping a fractal terrain around a ring. Do you mean in a 3D modeling sense?

Well, in Fractal Terrains there is the option to create either a 'planar' world or a synthetic world with the fractal function wrapped around the globe and pinched at the poles. How would I go about setting up a fractal function to wrap around the ring but not pinch the top and bottom edges as they are not poles? Or is this not possible in FT?

Projection wise, perhaps a series of maps, broken up into degree lots, so you'd really be making say, 8 maps of 45 degrees, or 24 maps of 15 degrees. Looks like a massive undertaking.

A very massive undertaking if I go with a full sized Ring World. Large enough that I'd probably want to break it up into 'equirectangular' sized maps. Looking back at my first post I realise that I may be wrong in opting for a ring with a height equal to the Earth's radius (through the poles). Any (reasonable) arbitrary figure should work - 20,000km (half Earth's circumference). So, simple maths tells me I get (940,000,000/2)/20,000=23,500 map sections, each covering 0°0'55.15'' (I think). That tells me I will NEVER actually be mapping out a Ring World, but it doesn't stop me from having fun playing with the idea. Though I might consider mapping important chunks.

Now I'm wondering if the ring should be flat or concave to result in varying solar input. If I do go with a concave model, then I would probably go with the same curvature as the Earth (north to south). This would obviously result in a distortion on a flat projection, but due to the scales involved it would be so, so tiny as to be hardly worth taking into account (I'm not 100% sure of this or the maths required).