How does `ionic resource` function generate splash screen images?

tl;dr What happens when ionic resource is is run? How are those splash screen images generated? Is anything added during the process?

The designer and I were discussing the “standard” for designing for mobile (both splash screen images and graphics throughout the app) when we came across something interesting. We found some advice about keeping the output above 2732 x 2732 but the designer wanted to know more about setting up the creative environment itself.

We checked out the default splash screen image (the Ionic logo with faint gray circles and grid lines) and saw that many cropped and scaled versions were generated for android and ios but something seemed strange about the largest of these. It appeared as though whatever process generated them also added details that were not in the original (in some versions, the grid lines extended far past the largest circle than in the original, proportionately).

Is this just because the defaults were actually created and added to the project individually for illustrative purposes? Does the resource generator actually add information where there is none in the original?

Thank you for your time! Please let me know if this was answered elsewhere.