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That looks like nice tool in Corel. Unfortunately Inkscape doesn't have anything like that, but there are still ways to do it. Yes, not only do the Offsets close the paths, it causes sharp corners to become rounded. I'll tell you how I usually do it. And there's at least 1 tutorial that comes to mind. However, you do still end up with a closed path that you have to break apart.
Hmm, it seems like I've heard of a new tool that will do this. But I can't quite remember where. OK here's how I would make lines in the "traditional" way.
1 - Duplicate the path and give it a wide stroke. Make it twice as wide as the distance you need the result to be from the original path.
2 - Path menu > Stroke to Path
3 - Add a stroke, and make it narrow again (it will probably automatically make it the same width as in step 1)
4 - Remove the fill
5 - Click on the 2 short end paths (selects the nodes)
6 - Click "Delete segment between 2 non-endpoint nodes" on the Node tool control bar (looks like this
)
7 - (optional) Path menu > Break Apart
I can't seem to find what I was thinking of, a new effect that would do this. But here's 1 of the tutorials I was thinking of.
http://screencasters.heathenx.org/episode-097/ I haven't watched it lately, and I don't remember how the author does it. But maybe it will be a different way.
Oh, and I just thought of a different way. Interpolation. Except that you first have to create 1 "parallel" line, then you can interpolate any number of them in between, automatically. Extensions menu > Generate from Path > Interpolate
http://tavmjong.free.fr/INKSCAPE/MANUAL/html/Extensions-GenerateFromPath.html#Extensions-InterpolateLet us know how it goes