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In Arcgis, there is a way to offset graphically the contour line of a polygon like below. I'm trying to do the same thing in a styling method (i.e the solution can't be by buffering physically the layer). QGIS does have an offset option, but it's an XY type offset that moves the position of the line.

graphic offset of lines

ANSWERS :

Way 1: use the geometry generator fill style. Just get in the box buffer($geometry,[your buffer distance]). The only difference is that Arcgis offsets the line whereas this solution creates a buffer, thus rounding the edges...

geometry generator

Way 2 : exact replica of Arcgis, inspired below by @iant answer : create in the style another style "Outline : Simple line". In this style, there is the offset box i was looking for ! It does exactly the same as in arcgis.

offset line

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  • I have a polygon layer, but the offsets I can fill in are just x and y, which just offsets the line to the side or up or down. Running 3.0.2.on Windows. Has this feature disappeared in the update?
    – Henrik
    May 6, 2018 at 14:01
  • Also, using the buffer($geometry,1.5) seems to offset it 1.5 map units (meters in my case) instead of pixels or mm. Is there a way to change this?
    – Henrik
    May 6, 2018 at 14:03

1 Answer 1

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Another way to do this is to duplicate the layer and use a negative offset to go outside the polygon when styling with a simple line fill. Or just have a simple fill and a simple line with the offset.

enter image description here

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  • I used your answer to collect what I did with my found method + what I did with yours that provided me the right answer. Hope it's OK for the "GIS SE" way of doing things :/ just an error in your answer, it's a negative offset one needs to do :)
    – gisnside
    Sep 9, 2016 at 15:57
  • Btw, no need to duplicate the layer :)
    – gisnside
    Sep 9, 2016 at 16:04
  • In the image above the outline overlaps itself quite a bit. In ArgGIS you can change the options from simple to accurate to prevent this. Is there a similar option anywhere in QGIS?
    – Ben
    Nov 14, 2021 at 5:21

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