Earth sphere viewed along the $S^2$ factor of $S^2 \times E$, where geodesics are great circles
Raymarching in S2 x E with an earth-textured sphere, emphasizing the S2 factor of the product geometry. The spherical geometry of S2 means geodesics are great circles, causing light to wrap around and potentially return to the viewer. The sphDot inner product on R4 restricted to the unit sphere computes distances.
Controls: WASD to rotate, arrow keys to translate.
