I've been playing around with a space sandbox type game idea, with a chunk based universe generation system using a poisson disk methodology for entity spacing. On a larger scale it would be good to introduce clumping of entities into galaxies. The ultimate goal is an open world game where the player flies around completing quests, though I doubt this will ever be realised...
Solar systems are all unique, with a number of orbiting planets and potentially asteroid belt(s). The planets also may have a number of moons orbiting them. I'd like to add support for more entity types than just solar systems/stars, such as nebulae, binary systems, pulsars and black holes.
As part of this project I decided to attempt to create shaders which would render stars and rocky and gas type planets, generating them procedurally from only random noise. I'm fairly pleased with the results, though they could certainly only be classed as proof of concept.
I also became interested about how one might achieve a pixel art style using these shaders to generate graphics on the fly. So created a 'pixel art' shader which clamps colours to bands and forces pixelated rendering.
This is as far as I've gotten for the minute (internships and university have waylaid any further progress), though I hope to come back to this project some time in the future. In the meantime feel free to get in touch with any questions.