Inverted Geometry Hollow World Traversal

The camera races low over rolling terrain that bends upward at the edges instead of falling away, rivers climb the walls, forests hang overhead, and mountains grow downward from a ceiling of land. Two traversal craft fly the inside of a hollow world while the camera struggles to keep up with the inverted geometry. They climb toward the central sun and emerge into a sky filled with hundreds of nested hollow worlds, each one visible through the next.