Four dimensions, one plane

Fourfold

A regular 5-cell is a tetrahedron with a fifth vertex in a direction you cannot point to. Dots sit on each triangular face — not inside the tetrahedra or the 4-volume — and each face takes a slice of the visible spectrum. Edges are dotted the same way, same size.

Red / cyan anaglyph is a parallel stereo shift — glasses optional. Drag to turn. Shift-drag to fold the fourth axis.