I've been writing a PostScript interpreter as a retirement project. I deliberately avoided looking at the Adobe source although I have been running the LaserWriter firmware[1] in MAME[2].

At the moment I'm just implementing the language. The core interpreter is done apart from error handling and a ton of operators. After that I'll decide whether to go on to the imaging.

[1] http://beefchicken.com/retro/laserwriter [2] https://github.com/mamedev/mame/blob/master/src/mame/apple/l...