Shader to bend textures

I’ve recently started using Three.js, hence I’m pretty new and might be on the wrong track. Yesterday I came across the following website:

It seems they’re using three.js as well - my assumption is they have a html structure and bind textures to these exact html elements. - Additionally using some kind of shader they are applying to the mesh’ I reckon they achieve that kind of bend effect.

What are your thoughts on this and how do I create that kind of shader?