HPGL plotter emulator implemented in Python.
It uses pyserial to commuicate over serial port, and PyCairo to handle drawing operations. A limited subset of HPGL v1 is implemented at the moment, but this is already enough to parse HPGL produced by Philips PM3382 oscilloscope (FW version 1993-06-12).
An example of image it produces: link (This image has been plotted by Philips PM3382 using a "Plotter -> HPGL" hardcopy output set up for A3 paper size, 2:1 scale, colors enabled.)
The same waveform as captured by a scope itself can be seen here.