A 2D visualization of a higher dimensional space, using HyperRogue's "crystal" method.
In this method, we represent the vertices of a d-dimensional grid as the tiles of a
{2d,4} tiling of a quotient space of the hyperbolic plane, in such a way that two tiles are adjacent iff they are adjacent in the grid.
in another interpretation, we are on a periodic surface in d dimensions, and we see the
surface as if the light rays were forced to go along it (press 'p' to see this surface, and 'k' to see, for each tile,
the coordinates of the grid point represented by that tile).
This is a magic cube (aka Rubik's cube). Hold the mouse over the center of a two-dimensional face
(in 3D, these are gray hexagons with a single colored strip; in 4D, there would be two strips) and press 'r' or 'm' to rotate that face.