With my interest in Geometry and Art, Escher's tiling images were an obvious target.
The image reproduced here is called Square Limit.
The fish that appears in the many locations in the image is identical (apart from size, orientation, sense and colour) everywhere it appears. Escher's remarkable talent was to design realistic looking animals with this sort of interlocking property.
Some would say this isn't Art. But few would say it isn't interesting.
Most of Escher's later tiling works have interesting Geometrical properties. Working out how to recreate them digitally is a challenge. I have spent may hours (over many years) perfecting the description of Square Limit, in a form that the computer can interpret.
It transpires that the description is in fact fairly trivial. As Escher no doubt knew.
What is even more amazing is that the image (and the tiling-pattern of course) are infinite. Regressing towards the edge of the image in ever-decreasing triangles.
One can only ever draw a finite part of that image, of course. And add a vague impression of the miniscule omitted elements.