> It's why even modern flight is centered around the idea of stacking multiple 2d environments
That's for sharing the space. It's not only a set of stacked 2D environments, those are also divided in road-like spaces, with a limited number of junctions.
That's for sharing the space. It's not only a set of stacked 2D environments, those are also divided in road-like spaces, with a limited number of junctions.