Oooooh!
I will have to look into that. Very useful!
Inkscape can also be very useful if you need a CAD model of a part, and the vendor only offers a 2d pdf (requirement: drawings in vector format)
Pipeline: pdf -> inkscape -> dxf -> CAD program -> 3d model.
A bit of work but muuch better than twiddling around with bitmaps as background to your parametric scetches.
A properly imported pdf can often let you mage very good guesses at the original parametric measurements of the part, even if curves have been chopped into multiple line segments and similar.
Biting the hand that feeds IT
