Didn’t see that the post is already years old, but it popped up in my list and I already wrote the reply.
A game engine is not going to load a system 1 light year in radius. It’s going to fake it.
- Things load in and out based on distance based on player position.
- Player position can be faked (aka teleported back to X0 Y0 Z0)
- Lighting is mostly faked, and not present at distance
- Lighting doesn’t necessarily work at huge or tiny scale.
- Distant objects are culled, simplified (LODs), or replaced with textures
- The playable universe is surrounded by a large textured sphere, showing stars etc. Optionally this sphere moves with the player’s position.