3

I am aiming to create a map showing species location records as points. I need to make the points different colours based on land type which is a polygon layer. So I want my species points to be a different colour to represent which land type they occur in. For example, records in farmland = blue, records in forest = green, records in grassland = yellow, etc.

I can count points in the layer etc. based on tools available, but I just want to show them differently based on the different land types on the map. I need a straightforward way to do it and I think this should exist. I can complete by selecting by each land type etc. individually, but with the amount of species involved this seems too onerous.

3

You can create a new field using Field Calculator to fetch the region name from the region layer. Then symbolize the point layer using the new field.

Example:

array_to_string(overlay_intersects('district_layer', kommunnamn))

enter image description here

2
  • 1
    Or even use the expression directly for categorized rendering (in the Value field) instead of creating a field. However, for larger datasets, rendering might become slow.
    – Babel
    Oct 28 at 8:07
  • Nice, didnt think of that
    – BERA
    Oct 28 at 8:13
2

A bit dirty solution using the "Expression String Builder" and the CASE function for your points

widnow

The following expression-like can be used:

CASE
    WHEN array_to_string(overlay_intersects('poly_test', "type")) = 'Type 1' THEN '#0A97B0'
    WHEN array_to_string(overlay_intersects('poly_test', "type")) = 'Type 2' THEN '#1C7947'
    ELSE '#FFD3E1'
END

It contains several functions: overlay_intersects() and array_to_string().

Your input/output may look like this:

output

0

You will have to spatial join them then add a field and calculate it with the landcover type. You could then export it as a new feature class or keep the join.

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