OK lets be clear about this, did you follow the links in my posting? Because if you had it should be perfectly clear that raspi2png works see screenshot of processing sketch Processing window not showing in screenshot. Further see TfGuy44 response to ben_suddenly. Now can you see my point. Both saveFrame and save work as expected, but that is not a screenshot, that ben_suddenly requested…
It is interesting to be able create screenshots to demonstrate that sketches run on raspberryPI, I was particularly pleased to find that raspi2png works as I had previously tried scrot got the same results as ben_suddenly, and therefore resorted to using saveFrame, but it doesn’t tell the story that the screenshot does.