Comment 5 for bug 391923

As with the older hpgl output, only path data are parsed correctly, and the bezier paths are converted to piecewise linear segments in the output.
All other objects must be converted to path at the moment.
Clones should also be "uncloned" at the moment.
I do consider to convert at least both ellipse and cubic spline to their corresponding primitives in hpgl format.

Programming with xpath is quite new for me, so I will probably make an improvement in using xpath, using relative path instead of the "everywhere path" used now (if I understand the tiny bit of documentation I have found correctly, this should be easy). This should also make it more convenient to use color (for pen selection) from stroke, whatever if this attribute is stored with the object or with a parent group (I think it will be easy to recurse through the parents with relative path until a valid stroke is found).

Concerning offsets, I think the offsets should be in a unit people can relate to, like inches or millimeters. The hpgl plot units are like mils, just rounded to match metric system. My personal preference would be the "mils like" plot units. Any other opinions on this?