Generally, what do slow down the game on a old computer or phone?

[Drona]

Hi, this post explains how sprites are rendered and what possible benefits of a tile map are:

About scene rendering

Every object in a scene is rendered individually, in every engine, yes. Objects are Culled (not graphically rendered) when outside of all of the layer camera’s current view, though. Sure, if you have enough of them on screen at once, or enough logic impacting those off screen at once. I don’t understand the question here “as a whole”, pixels are pixels. The more pixels you have to render, the more performance it has to take. It doesn’t matter if the pixels are part of object A or object B. …