QGIS » QGIS Application

Trying some silly things I found "Geometry generator" of feature styling to create wrong geometries when I used @map_extent_width and @map_extent_height in it.

I ended up with the following test case.

Use this is label for some feature to see the values live updated:

'Center: ' || x( @map_extent_center ) || ' ' || y( @map_extent_center ) || '\
' ||
'Width: ' || @map_extent_width || '\
' ||
'Height: ' || @map_extent_height

If you resize the map, the Width and Height values never update while the Center works as intended.

Open the Python console and use this to manually request the map's width and height:

"Width: {} Height: {}".format(iface.mapCanvas().extent().width(),iface.mapCanvas().extent().height())

To my understand these should show the same values for the width and height.

When I move the map and print with Python again, I see the new values. The @map_extent_width and @map_extent_height in the label are not updated though.