Some games that have a lot of keys end up with complex custom layouts. Hard to remember it all.

While I know one could just screenshot the layout, then manually invert it and then print it so one can have the paper nearby to refer to, it would be more user-friendly if one could just press a button and have the image be saved as a pdf and already inverted for printing.

Then the user can either send the pdf to a network aware printer like phones can do, or transfer the pdf to another device to do the same.