I spent many days trying to troubleshoot some HP/GL2 plotter code in the distant past. I eventually concluded that the real problem was with the implementation--I was working with code that was written by others and went a little crazy with coordinate transforms. Oops--worked as expected on one non-HP plotter. Drew the image inverted on a HP plotter. The HP implementation appeared to break if you flipped the world too many times. That was a *long* time ago, my memory is fuzzy by now.
(And in later days I saw a firmware update for a laser printer cause it to spew gibberish when fed embedded HP/GL2 code. This was in the era where there were still DOS programs running under Windows and somebody didn't check that it still worked right.)
(And in later days I saw a firmware update for a laser printer cause it to spew gibberish when fed embedded HP/GL2 code. This was in the era where there were still DOS programs running under Windows and somebody didn't check that it still worked right.)