In april 2020 I created this demo / proof of concept of a game whose mechanics is based on folding of the sheet of paper. Each side of the paper represents completely different environments. By folding the paper those environments could be combined as a result letting the main character reach the goal (this part is not implemented in this demo).
In short, the idea is to have two cameras for each side of the paper. Each camera renders its own environment and all objects on that side of the paper into a render texture. Those render textures are then used to render quads which are clipped by other geometry to mimic the paper folding. Funny thing is that to achieve seamless movement of the character between the foldings it’s necessary to have an extra clone of the character per each folding (since it’s possible to make the character stand on 4 corners of the opposite side of the paper).
Although the idea is not mine, the implementation and design of the demo are my own.
Character and tree sprites are by Kenney.
Source: https://github.com/dotsquid/PaperFolding
Demo: https://dotsquid.gitlab.io/paperfoldingbuild/