Snap to pdf

[Anonymous]

I want to be able to snap to pdf!

I had to work with pdfs recently using Autocad and it had this function, which was really useful. According to me it snapped at about 2 mm accuracy, which was enough.

[Anonymous]

Since this might be useful to some I will refrain from voting, but I strongly discourage my clients from any practice which tends to produce inaccurate results. I have found that models that are slightly out of whack are the worst as it is very difficult to find the errors.

[Anonymous]

I think it's always better to have the choice of snapping than having no snap at all. It's an entirely different discussion how you are going to use it - to produce inaccurate drawings or just for reference.

[Anonymous]

kliment wrote:
I think it's always better to have the choice of snapping than having no snap at all. It's an entirely different discussion how you are going to use it - to produce inaccurate drawings or just for reference.

I suppose for things like site plans this might be good. I'm all for having more options as long as they are useful and don't get in the way of more important things (at either the user or developer level). I don't see any need for snaps when the drawings are just for reference though.

I certainly would not want to see this as the default behavior since there is no way (at present) to turn the snaps off and this could force inaccuracies or at least make it very difficult to avoid them. Since I use PDFs as references very often this would be a nightmare for me. (Then it could get as bad as using Revit where the PDFs have to be converted to bitmaps for import.)

[DaveOlufs]

Snapping to PDF is the same as tracing a blueprint. Nothing is to scale with expansion in the printing process. Also it assumes, whomever drafted the original plan did it to scale. It is truly garbage in, garbage out.

[DaveOlufs]

I suppose for things like site plans this might be good. I'm all for having more options as long as they are useful and don't get in the way of more important things (at either the user or developer level). I don't see any need for snaps when the drawings are just for reference though.

As a another point of reference... I recently used a PDF site plan and found it to be in error by over 5 feet over 450 feet. Normally, I layout the site according to bearings and distances hoping to close the perimeter. When I did this, I noticed the error. The building was also off be as much as 3 feet. My philosophy is to start a project with as much correct information as possible so as not to carry errors through to the field during construction.

I've taken over jobs where building dimensions were in error and owners don't understand... nor should they tolerate it.

[stefan]

Well,many PDF drawings are made from CAD drawings and are quite accurate. If you snap to the longest known distance you can make quite accurate drawings. I have been retracing several senior housing projects over the last week, where I usually had to start from PDF files and not being able to snap is a bummer, when the drawing is there, visible and completely as accurate as the CAD drawing it was generated from - AutoCAD usually 😉

I'm just replacing the full model with Zones for area calculations.

[Karl Ottenstein]

stefan wrote:
Well,many PDF drawings are made from CAD drawings and are quite accurate.

For those drawings, which are actually vector PDFs like that and not raster (image / scanned) ones ... we should definitely have snapping.

A workaround in the PDF-from-other-CAD case is to convert to dwg/dxf. Those with Adobe Illustrator, e.g., can open the PDF and then Export it as dwg/dxf and place the result as an external drawing in AC for full snap tracing.

Cheers,
Karl

[stefan]

And while we are requesting: optionally disabling line weights would also help a lot. In fact, there should be no real difference to the user between XRefs and external drawings.

[Anonymous]

I also had in ming snapping to vector pdfs. Otherise you would not be able to snap.
Stefan, if you have Aotocad, you can use the span option there.