Setting max zoom level of QgsRasterLayer with PyQGIS

Question

I'm using PyQGIS to add QgsRasterLayer layers to my project.

This is how I create the layer:

urlWithParams = "type=xyz&url=http://ecn.t3.tiles.virtualearth.net/tiles/a%7Bq%7D.jpeg?g=1"
rlayer = QgsRasterLayer(urlWithParams, "Bing maps", "wms")

I can set their max zoom level via the QGIS UI (Properties -> Source -> Max Zoom Level, see attached image), but I'd like to do it programmatically via PyQGIS. I've found that this class has the setMaxZoomLevel method:

https://www.qgis.org/pyqgis/master/core/QgsVectorTileBasicRendererStyle.html

but I cannot find how to go from a QgsRasterLayer to its QgsVectorTileBasicRendererStyle.

Has anyone done it?

Answer 1

I analyzed the source of the layer and saw, that the "min/max zoom level" are stored in the DataSourceUrl as the zmin/zmax parameters:

print(iface.activeLayer().source())

type=xyz&url=https://tile.openstreetmap.org/%7Bz%7D/%7Bx%7D/%7By%7D.png&zmax=18&zmin=1

You can replace the zmin/zmax values (i.e. using regex):

import re

layer = iface.activeLayer()
current_source = layer.source()
print(current_source)

new_zmin = 1
new_zmax = 18

updated_source = re.sub(r'zmin=\d+', f'zmin={new_zmin}', current_source)
updated_source = re.sub(r'zmax=\d+', f'zmax={new_zmax}', updated_source)

layer.setDataSource(updated_source, layer.name(), "wms")

layer.triggerRepaint()

Result:

Answer 2

@DidacBusquets answered his/her own question:

The following code does set the maximum and minimum levels of the layer (by appending it to the URL):

"type=xyz&url=http://ecn.t3.tiles.virtualearth.net/tiles/a%7Bq%7D.jpeg?g=1&zmin=1&zmax=20"
rlayer = QgsRasterLayer(urlWithParams, "Bing maps", "wms")