How do I change the "3D resolution" of the engine?

So I need to optimize my game and I really like pixelated looks.
In fortnite, I found what Im looking for.

As you can see, the performance gets optimized by the pixelation/resolution, but all tutorials online only show post processing pixelation and i don’t think that’s the same thing.

Any ideas on how to create this optimizing and pixelating render setting?

Are you talking about the console command r.ScreenPercentage?

To achieve the effect on the left open the console with backtick/tilde.

` r.screenpercentage 25

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easyCSV : Read data from any CSV and put them in an easy-to-access string map!

iTween : Free, smooth, procedural object animation

There is also a slider for that in the viewport settings as well