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I am using QGIS to do some analysis on the reach of bus stops in a small town in Sweden with a set buffer of 400m, however I want the results to not have any overlay.

This is the original mapBus stops with background

When setting a buffer of 400 meters I get a lot of overlay between stops, however I would like a result similar to this:

Correct solution

Making this "correct" layer took a lot of manual effort, and something I'd rather not do for the remaining 30 bus lines =)

I've tried using Voroni Polygons (with dummy bus stops to expand the reach of the polygons) and a buffer layer, but I see no way to intersect these based on the ID.

Is there any way to do this or any off-the-shelf solutions to creating buffers without overlay which I could use?

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  • In case anyone found had the same issue: the issue is actually answered here in the last comment from Victor below the accepted (but wrong) answer
    – Vincé
    Commented Jul 12 at 14:27

1 Answer 1

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I'm not quite sure if I got you right when you say "making correct layer" but I assume that you wan't to merge your distance buffers. In QGIS simply do:

Vector > Geoprocessing tools > Fixed distance buffer

  • select your input point layer
  • choose distance and segments
  • make sure to tick "Dissolve results"
  • set your output path

Your result will look similiar to what I've created:

dissolved buffers

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    Hey, sorry for not specifying better, but the second image is the result that I desire. I don't want the polygons merged but separated without any overlap. I use it for tracing points to see which bus stop is the closest to it.
    – kesoar
    Commented Oct 7, 2016 at 8:34
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    I think your approach to make use of voronoi is not too bad, you can find something similar here: gis.stackexchange.com/questions/23140/…
    – dan_ke
    Commented Oct 7, 2016 at 9:55
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    I'm playing around with this problem, and the issue I'm finding is calculating a decent buffer region for the voronoi tool. too small and you can't effectively intersect with your dissolved buffer region. Too large and the voronoi results start to change so you won't have the right nearest neighbour boundary for certain bus stops (those nearest the edge of you area of interest). @dan_ke could you expand your answer to include intersecting a voronoi layer. Commented Oct 7, 2016 at 10:09
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    @Knightshound - You certainly make a good point. This is my attempt and the result.
    – Joseph
    Commented Oct 7, 2016 at 11:31
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    That worked for me! I used dummy bus stops, located far away from the rest of the points. This gave me a Voroni layer which was large enough to use for clipping the buffer zones. Not a perfect solution, but it worked. Thanks for the help!
    – kesoar
    Commented Oct 7, 2016 at 11:48

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