How to make such an erase hover effect?

Question

css

Hey! Are there any ways to implement such an idea? Recorded a video.
https://drive.google.com/open?id=1JxIchObGQO-J0Ap1...
Erasing the top image on hover and mouse movements. At first we see just a blue hover (2), then if we move the mouse, the picture below the layer opens (3).

Answer 1

There are two options here, either draw everything on the canvas, or on the svg path. It’s easier on canvas, the main thing here is to be able to draw a circle with a texture, but then it’s clear, there are a lot of circles that overlap the background.