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equivalent to "buffer

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#1
frax

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Hi - just a simple question(?)

How do one do the equivalent to "buffer"? I basically want to extend the size of a polygon. I get all kinds of weird results if I try to add a bigger stroke and then expand it, which I would have thought would be the way to go...
Hugo Ahlenius
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#2
benbakelaar

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Which software are you working in?

#3
mike

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hugo,

i'm assuming you are using Illustrator to do this. What you can do is just create a stroke around your polygon, then use the Align Stroke to Outside option. this should give you an even stroke around your polygon.

#4
benbakelaar

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If it's in Illustrator, you could use the Scaling tool, unless it has to be extended by a specific amount?

#5
frax

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sorry, forgot to mention what software it is.... it is illy.

scaling won't do it, since scaling and buffering to expand things are not the same (try it with a few odd polygons, and you'll see what I mean)

Adding a stroke around the polygon works, but not when I try to move it from it being a stroke - if I try to expand it I always get odd compound paths, if the stroke is wide... (and then I would have the hassle of trying to add it to the polygon)
Hugo Ahlenius
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#6
CHART

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OK,
Outline stroke (under path command)
Ungroup
Compound path release....

You will get 2-3 objects ... should be able to set stroke and fill to get what you want.

this now I think might do it!

(good thing I can edit my post)

Trying to post an example....
Chart

#7
frax

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Here is a little demo...

Ben, as you can see on the top example, scale doesn't cut it.

Jacques and Mike -- see my little example of what I am seeing when I try to expand the path, or outline the stroke (the latter option doesn't honor the "align stroke" settings, so it is less useful). I get a lot of stray odd things if the path is reasonably complex, even if I simplify it a bit.

I just want to grow my existing polygon a bit...

Posted Image
Hugo Ahlenius
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#8
frax

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btw, what I am trying to do is totally non scientific and quantative (of course) and maybe it is just easier to draw an expanded polygon by hand...
Hugo Ahlenius
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#9
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Try simplifying your polygon to straight segments (straight line option in the path simplify menu) BEFORE you outline stroke etc...
Chart

#10
Maisie

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I'd use Offset Path (rather then Outline Path), then run Simplify Path at 98% or so.

#11
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Well well, that seems like a better option.... :)
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#12
benbakelaar

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Thanks for the explanation Hugo, I appreciate it! Really easy concept once you see a visual :)

#13
frax

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Thanks Jacques, you found the solution! Simplifing to straight segments did it - now I am able to outline stroke (expand appearance still turns up strange results, as well as offset path).
Hugo Ahlenius
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http://nordpil.com/
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