Implementation of Henderson's Escher fish in Elm ported from https://github.com/einarwh/funfish 's F# implementation.
See https://eprints.soton.ac.uk/257577/1/funcgeo2.pdf for Peter Henderson's paper.

1. Check the results on https://janbols.github.io/funFishElm/web/

or

1. Build using elm-make src/Main.elm --output build/index.html
2. Open ./web/index.html in your favourite browser

or

1. Build using elm-reactor
2. Open http://localhost:8000/src/Main.elm in your favourite browser

See https://guide.elm-lang.org/install.html for instructions on how to install elm.

Also see https://www.wikiart.org/en/m-c-escher/square-limit-colour for the expected end result as drawn by Escher.