Background parallax?
First, it’s a technique mainly used in traditional (2D) animation using a multiplane camera (camera above several layers of glass).
You force the background to move past the camera more slowly than the foreground. This way, you create an illusion of depth.
In the 80’s, parallax game background was eventually used in games, then years later in web design, too.
How parallax is working?
You just need to place all the graphic assets on top of each other, make sure you don’t mess with the order, to adjust the speed and that’s about it!
Chalet by night & by day (6 layers & 10 layers):
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