Take a few perfectly reflective spheres and arranged them at the vertices of a polyhedron.
While neighboring spheres share a point of tangency, others are disjoint. Each polyhedron is set inside a bigger, non-reflective sphere which has a pattern. The pattern is reflected in the smaller spheres over and over again. One reflection symbolizes an inversion on a sphere. All infinitely many inversions generate the limit set of the action of a Kleinian group, which is a fractal. By using reflections instead of inversions, this fractal is approximated.
Here twelve perfectly reflective spheres are arranged in an icosahedron. For the pattern of the outer, non-reflective sphere the Roman Candy image is used, which you can find in the SURFER gallery.
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