HPGL Export for Rhino is a HPGL plot file export plug-in for Rhino. This plug-in gives Rhino the ability to export geometric data from Rhino to HPGL Plot (PLT) files.

HPGL is the Hewlett Packard Graphics Language designed for specifying 2D graphical information for the HP range of plotters. It was not intended as an interchange format but some software suppliers use it as such. HPGL is a command set embedded in the ROM of pen plotters to help reduce the work required by applications programmers to create plotted output. HPGL uses two-letter mnemonics as instructions for drawing lines, circles, text, and simple symbols.

HPGL Export for Rhino breaks down Rhino entities into pen movements and writes them to the output plot file. HPGL Export for Rhino supports the following plotters: 
Hewlett-Packard 7475A
Hewlett-Packard 7550A
Hewlett-Packard 7580B
Hewlett-Packard 7585B
Hewlett-Packard 7586B
Hewlett-Packard Draftmaster 1 (7595A)
Hewlett-Packard Draftmaster 2 (7596A)
Hewlett-Packard Draftpro (7570A)
Hewlett-Packard Draftpro-DXL (7575A)
Hewlett-Packard Draftpro-EXL (7576A)

HPGL Export for Rhino is very easy to use as it adds a new file type to the Rhino File Save As dialog box. To export a PLT file select Save As from the File menu. Select "HPGL Plot Files (*.plt)" from the "File of type" combo box and select a PLT file to export to.