Improving buffer smoothness using PyQGIS?

Question

I am trying to automate buffering of objects in QGIS using Python. The function below using QgsGeometryAnalyzer works but the output is blocky. I understand that the smoothness of the buffer edge can be improved by increasing the number segments per quarter but i am unsure of how to do this using Python or even if it is possible.

This note and the linked github pull request suggests not.

Is there an alternate method i am missing that would allow me to increase the number of segments and so the smoothness of the buffer object?

QgsGeometryAnalyzer().buffer(LayerToBeBuffered, "Output.shp", 2000, False, False, -1)

Answer 1

You can use the buffer() method. It applies to a geometry object. For example, using the following code:

layer = iface.activeLayer() # for example
for feat in layer.getFeatures():
    geom = feat.geometry()
    buffered_geom = geom.buffer(200, 30) # this is the relevant part

you will create a buffer around the current feature with a radius of 200 (expressed in the units of measurement of the project) and composed of 30 segments.