When it comes to making sure a video game is playable, even for low end devices/consoles, one aspect that a developer can use is a cardboard cutout. A cardboard cutout is a (usually) high quality 2D texture that is meant to represent a 3D object within a game.
They are also a fairly old technique, with less appearances in modern games, but they can still be found, and are still useful when trying to make a game.
There are several reasons a developer would choose to go with a 2D texture instead of a 3D model. The first reason is that it saves space. The less resources that need to be rendered — the amount of things inside a game that need to be used — the better the performance. Or in other words, they save on resources, allowing the engine to focus on more important aspects of the game.
Better performance usually leads to a better gaming experience. There will be less lag — how much the frame rate of the game drops — and loading times within the game will be faster.
The second reason is that it is a quick and simple way to add details into the game without having to spend a lot of time and money on making a 3D model. If the cardboard cutout accomplishes what a 3D model can, then there is no need to go beyond that.
The third reason is ease of use. It is a lot simpler to make a flat texture — anybody with drawing skills can make one — compared to making and rigging a full 3D model (which requires the model itself, rigging, and a texture overlay). Why spend a bunch of time making a model that most players won’t appreciate when you can make a 2D texture that accomplishes the same thing?
The fourth reason is world building. By placing cardboard cutouts of details beyond the playable area, the developers are able to make the game feel connected and large, instead of a bunch of small maps interconnected.
In the image above, the castle in the background is a cardboard cutout. It doesn’t need to be anything else.
From the perspective of the player, it is far enough away that 3D details are all but lost, and since this is supposed to represent the castle and not actually be it, it just needs to be detailed enough to look like the real thing.
It also acts as a waypoint marker of sorts. At a glance, the player knows which direction they should go if they want to head to the castle without having to stop playing and taking out an in-game map.
In the .gif above, the flowers are cardboard cutouts. The reason for this is the same as detailed above: there are too many of them, and they are quite small, so it makes more sense to make them cardboard cutouts.
However, as you can hopefully see, the flowers are always facing the camera. This effect is done to make the flowers look 3D, even though they are only 2D.
When the player pays close attention to it, it looks fake. But when playing the game and only noticing it in passing, it tricks the brain into seeing them as 3D objects.
But whatever the reason, cardboard cutouts are a technique that specializes in saving space with minimal loss in quality.
