I am trying to create smooth looking polygons by gridded points in QGIS (2.18.16), with a fading effect towards the boundary of the polygons (halftone effect).
By using the 'fillGrid' function from Rob J, I managed to create gridded point pattern in Geometry Generator.
Now I would like to add a size decrease of the point marker towards the boundary of each polygon starting from a maximum size (e.g. 2 mm) to a minimum size (0 mm). What is the best way to do this? Maybe there is a faster way by using the standard 'point pattern' option as symbol layer type?