How to make and process a new image(distinct from the screen)?

I think you are referring to PGrapics.
One thing I should mention is that text has an option with 5 parameters which limits the text to a bound area. You should check it out in the reference. If you want to actually have a scroll effect, the keyword to search in the forum is “panning” and you should get some hits that you can apply to your use case.

Kf