6

I have 3 layers that sometimes have overlapping features. I need to use a thin outline style to interpret the area within the polygon and want to be able to see on the map when the features overlap. Think of it as 3 identical polygons. How can I style this?

  • 1
    One outlined, one hashed to the left, one hashed to the right, using three distinct colours. – Erik Nov 13 at 8:07
6

You can set each layer to render differently when there is an overlap with another layer. Go to the style, expand layer rendering, then select multiply under layer blending mode.

If you want to see overlaps with polygons from the same layer, you could (also) set the feature blending mode to multiply.

enter image description here

  • Hmm, the multiply option makes it a third color when overlapping two features but dissapears when there is only one. Will look in to it some more. – Nils Fernquist Nov 15 at 7:23
8

I use the 'Line Pattern Fill' with a different colour and line fill rotation for each layer.

It can be useful to create a variable in the project properties to use as the spacing between lines, fill line weight etc, this will make it easier to adjust all layers by changing one or two variables instead of lots of variables for different layers.

See below for examples:

Single Layer

1

Two Layers

enter image description here

Three Layers

enter image description here

5

As another option, you may be able to add a layer dedicated to show the overlapping area, so that you can keep original three polygon layers, showing thin outlines only.

Run Build virtual vector tool (in QGIS Processing Toolbox > Vector general), with Create Unioned VRT option.

enter image description here

Put the newly created layer underneath and set color and transparency.

enter image description here

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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