Resolution of imported PDF files

mac

#1

If drawing files from third parties are not available in CAD form, you often have to import a PDF version instead. The trouble with that is that the resolution is very poor compared to the original PDF file viewed in, say, Acrobat. There are ways of converting the file before importing (see this thread: Best image file format for import) but I would like to see the import process produce a higher resolution image in the first place. Surely it could be built in so as not to require pre-conversion?


#2

SketchUp has a limit to image resolution that it can handle. By default, it downsamples everything to a maximum of 1024 x 1024 pixels.You can increase this to 2048 x 2048 or 4096 x 4096, depending on your graphics card capabilities, by checking the “Use maximum texture size” box in Window menu>Preferences>OpenGL.

Anssi


#3

I have been using pdf2CAD - it costs $$ but has been worth every penny as I do this at least 2-3 times per week. It doesn’t convert (to lines) any part of the file that might have been rendered as an image in the PDF file, but for most drawings from architects and engineers it works great.

I usually open it up as a DWG in DraftSight to clean it up - but bringing it straight into SketchUp works too.

Bringing in PDFs is still handy though for hand sketches and projects that might have rendered elevations or sections. But generally having real geometry to work with is much preferred.


#4

That looks useful although it again means a two part process. Also, for occasional use, it is far too expensive. I can see how it is justifiable if you use it as often as you do. What would be good is to have something like this as an online converter and a pay per use option.


#5

I have no problem with bringing it into PDF2CAD first, then importing it into SketchUp as a DWG (with or without my other step of cleanup in a CAD program). What I really like is the ability to have geometry to look at, hide, move, etc. rather than a pixelated image.

Even if the resolution was higher on the PDFs, you still wouldn’t be able to snap to geometry. Not really a problem for many folks… but a huge boost in efficiency for me.



#6

You can try this:

http://dwg.autodwg.com


#7

That looks like exactly what I was after. I have just tried it with a PDF which was a scan of an architect’s drawing done manually. So it was a raster PDF. Creating a DWG from that is almost useless and no real advance on importing it directly into SU.

I agree with you entirely that something that produces a vector file that you can work on directly without overdrawing must save a great deal of time.


#8

There are a lot of automatic raster to vector converters, but in my experience you will spend more time correcting the resulting mess than redrawing it from scratch.

Anssi


#9

Autocad 2017 can now import (almost properly) pdf and generate appropriate geometry and layers.
However, it’s true that sketchup import should be better to allow high res or lossless import.


#10

PDF is a meta format which may contain raster data as well as vector data.

Raster data is obviously not of much advantage for geometry creation in a vector based CAD application but can be used for manually tracing over the drawing. Additionally, raster data could/should be saved in a raster format as e.g. PNG anyhow without the need of wrapping a PDF envelope around.

Regardless of this, the free Adobe Reader allows to export a PDF via “File > Save as… > Image…” to a raster format in the desired quality/resolution etc.

For converting vector data inside a PDF free Inscape (or commercial Adobe Illustrator; Corel Draw probably too) can be used to save as a vector-based DWG/DXF.