It depends on the PDF.
If it was produced from a vectorial program like Archicad then if you can't snap to the points directly you may be able to 'explode' the PDF and convert it to lines.
I know Archicad PDFs can now have layers but can't remember if the points are snap-able or not or if you always have to explode the PDF first.
If it is a scan from a photocopier then you can't even explode it as it is just a bitmap image.
Barry.
One of the forum moderators.
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