23

To not have overlapping polygons/features, I normally use one or more polygons to clip/shape other polygons. This is often much faster than tracing when adding polygons etc. I cannot find this functionality in QGIS.

The highlighted polygon is overlapped by the adjacent (west/left) polygon with a straight edge. I want to cut the adjacent polygon with the highlighted.

The highlighted polygon is overlapped by the adjacent (west/left) polygon with the straight edge.

Improve this question
0

4 Answers 4

Reset to default
13

You can substract (clip) a polygon from another of the same layer by using the plugin Clipper. You have to choose the polygon you want to clip and then you do Vector->Clipper->Clip and the plugin substracts the polygon from the bigger one. Then you choose the clipped polygon and delete it.

If you can't choose the polygon you really want because the QGIS chooses the other one, you can use the identify tool (i) and then choose the right polygon by using the Toggle Feature Selection from the Identify Window.Toggle Feature Selection By doing this you can select the polygon you want when there is an overlay between features.

Improve this answer
2
  • This is not working for me in QGIS 2.18.15. I have 2 polygons in same layer, selected the one I want to cut (clipper) out of the other (the clippee), selected vector>clipper>clip but nothing happens. also tried the preview menu options but nothing happens. I confirmed nothing happened by dragging the clipper polygon off of the clippee to confirm there was no hole created in the clipee. Also tried other way around (selecting clipee) but no change. Anyone else have this working with a recent build?
    – user25644
    Commented Feb 22, 2018 at 18:12
  • I have used it with the 2.18.15 and use it with the newest 2.18.15. Maybe you have bad geometry with your polygons?
    – geoSAM
    Commented Feb 22, 2018 at 18:17
9

There is a plugin called Digitizing Tools that has the feature "Cut with polygon from another layer"...

In the image below I am editing the Green layer and have a polygon feature selected from the Purple layer.

When I click the 'cut with polygon from another layer' it will remove the portion from the Green layer that I had selected in the Purple layer:

enter image description here

enter image description here

Improve this answer
3
  • 1
    Not quite what I'm looking for, but a useful tool in other relations. I still think that when digitizing, you need to be able to cut a polygon with another (from same layer) as a quick and simple task.
    – Johan Fast
    Commented Sep 1, 2015 at 6:15
  • 2
    I found the tool I was looking for! It's called "Clipper".
    – Johan Fast
    Commented Sep 1, 2015 at 6:19
  • @JohanFast - You should post your comment as an answer buddy and accept it (after 2 days of first posting) so that the question is closed off :)
    – Joseph
    Commented Sep 1, 2015 at 9:05
8

I found the tool I was looking for! It can be done using the plugin called "Clipper".

Improve this answer
4

You do not need to install any plugin to do that operation: use SAGA tools. Go to Processing>Tools (tool's pane opens on the right of your screen)>SAGA>Vector polygon tools>Polygon self-intersection. This tool will basically create a new layer composed of every possible combination of intersected polygons into the same layer.

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.