I spent a heap of time about 15 years ago playing with various mosaic software before landing on https://www.andreaplanet.com/andreamosaic/ - I built an endlessly zooming mosiac for a museum - https://www.youtube.com/watch?v=UdC8sk08Vc4
It was supposed to run for 3 years but last time I was there it was still playing on the big projector.