I design parts and assemblies in Solidworks. Sometimes I am asked to provide line art for technical illustrations in manuals. I bring the 3D cad assembly into a 2D drawing placed in a particular position. I then output a .dxf or even a .pdf that I provide to the tech pubs people that they use with Corel or Illustrator. We are thinking of starting to do our manuals with the sort of style where the line art illustration uses two line weights. here is something I didn't create but found with a google image search for technical illustration styles.
https://drive.google.com/open?id=0B-lFPuPhG-viWnRtOTA2YW80WE0
In the example the whole thing is outlined but so are some of the features. I would mind a simple technique that can automate the selection of all the outside borderlines. I can pick the few lines that are interior to that manually selecting them.
I think there are some expensive additions to Solidworks that can do this but I am wondering if there are some tricks in Coreldraw to accomplish this other than select lines by line or with selective windows across the outlines. Making manual selection even more of pain I am finding with X8 that when i do select more than one line element with a shift select or with a window select I lose the line weight entry box in the toolbar.
steve krause said:a simple technique that can automate the selection of all the outside borderlines.
I think the possibilities for that would have a lot to do with how the 2-D curves come into CorelDRAW when they are imported. If I do something similar with a PDF from Autodesk Inventor, it LOOKS good in CorelDRAW, but it's a big mess of curves that doesn't lend itself well to creating a closed outline of the whole part.
One thing you might consider would be converting it to a 1-bit bitmap in CorelDRAW, then using PowerTrace to trace that to get different vector content to work with that might be easier to get a closed curve from.
The import from PDF looks like this:
After converting to bitmap, then doing a Centerline trace, I had three curves. After deleting the two curves that represented the holes, I had one curve that looked like this:
That's all one curve, so it was easy to use the Eraser tool to tear it up enough to not leave any closed "islands" in it:
That outline is "tight" enough that Smart Fill works on it:
...so there's a closed curve of the outline, ready to apply whatever outline style you wish to it, then clear the fill.
If I use the procedure above on a copy of the original imported PDF content after pasting it into a higher layer, then when I switch the layer with the original stuff back on, it looks like this:
Your mileage may vary...
I think I understand the strategy. Make a single outline by erasing everything inside. Fill it because by erasing the inside stuff it can be a closed curve if the centerline trace attached all the outer lines together. Change the line weight to heavier. Then clear the fill and lay that on a copy of the original.
The image I have is not cooperating after I do a centerline fill to try to get something easy to erase. It seems it would be just as easy with this particular image to not convert to bitmap and instead manually select and delete all the interior objects leaving only the outline that gets heavier and composite that layer over the original.
link to a file