Escher and the Droste effect – WebGL fragment shader

I don't have anything intelligent to say about this - but this for me is one of those moments where I feel positively in awe of how next level some people are.

I thought that this gif <a href="https:&#x2F;&#x2F;lh3.googleusercontent.com&#x2F;-Izdubw7RJWk&#x2F;URK2tZdqxzI&#x2F;AAAAAAAAASs&#x2F;x0cXWbjrVLQ&#x2F;s426&#x2F;photo.jpg" rel="nofollow">https:&#x2F;&#x2F;lh3.googleusercontent.com&#x2F;-Izdubw7RJWk&#x2F;URK2tZdqxzI&#x2F;A...</a> was already impressive, but this is just completely incredible.

Here is a mathematical reconstruction of the print with several fly-throughs: <a href="http:&#x2F;&#x2F;escherdroste.math.leidenuniv.nl&#x2F;index.php?menu=intro" rel="nofollow">http:&#x2F;&#x2F;escherdroste.math.leidenuniv.nl&#x2F;index.php?menu=intro</a>

I&#x27;ve seen this painting before but didn&#x27;t think much of it. Now that I can see what&#x27;s going on, I am dumbstruck with how abstract and novel this concept is.<p>This spacial reasoning ability is so amazing.

Why is there visible angular distortion when you zoom in? It shouldn&#x27;t happen if you do the Droste effect correctly, like this: <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=9WHdyG9mJaI#t=0m43s" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=9WHdyG9mJaI#t=0m43s</a>

Bravo! I&#x27;ve taken a few runs at trying to put the Droste effect in a shader and never got close to what you&#x27;ve done. Great job!

Excellent! Thanks for sharing!