HPGL Import for Rhino is a plug-in for Rhino. This plug-in gives Rhino the ability to import graphical data from 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 plot files contain information regarding the movement of the pen of the HP plotter. HPGL Import for Rhino converts these pen movements into Rhino entities and adds them to the contents of a new Rhino drawing. HPGL Import for Rhino supports plot files created by drivers for 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 Import for Rhino is very easy to use as it adds a new file type to the Rhino File Open dialog box. To import a PLT file select Open from the File menu. Select "HPGL Plot Files (*.plt)" from the "File of type" combo box and select a PLT file to import. A new drawing will be created containing the imported PLT file.