Changing polygon circles to hexagons using QGIS

Question

I received an answer to Changing Points into Hexagon-Polygons using QGIS, which enabled me to change the point to polygons using the "Rectangles, Ovals, Diamonds" tool, which I used circles.

My client wants the shape to be a hexagon based on the width field in the data. The data field has a meter amount as in 5 for 5 meters.

Is there any way to make the circle a hexagon?

Answer 1

Yes, try to use the make_regular_polygon() via the "Geometry by expression" from the Processing Toolbox (Ctrl+Alt+T).

Let's assume there is a layer 'Polygon' with circles, see image below.

violet points are just the base for circles

In the "Geometry by expression" window use a formula for creating hexagons in 'Geometry expression' field accordingly for

inscribed

with this expression

make_regular_polygon(centroid($geometry), point_on_surface(boundary($geometry)), 6, 0)

and get the output

circumscribed

with this expression

make_regular_polygon(centroid($geometry), point_on_surface(boundary($geometry)), 6, 1)

and get the output

Answer 2

You can get hexagons from circles using Centroids and Rectangles, Ovals, Diamonds tools, consecutively.

"Centroids" tool generates centroids, of course. New "Centroids" layer has all columns of "Circles" layer. Then, you can generate hexagons based on Width field using "Rectangles, Ovals, Diamonds" tool as in the image.

1. Shape: Oval
2. Width/Height: Click "Data defined override" button > Field > Width
3. Segments: 6

I assume your data uses a projected coordinate system. In case of geographic, this method does not work.