QGIS » QGIS Application

I am trying to construct a legend for sized symbols, using a separate vector layer to do so.

I have three points exactly at the same location. When I size them according to a different value each using a size scale field with the default center anchorpoint, I get the result shown in qgis_symbol_legend_anchorpoint_center.jpg.

Playing around with the manual offset, I can get what I want as a final result (see qgis_symbol_legend_anchorpoint_manualoffset.jpg).

However, this is a bit tedious, and I thought that I could simply define the bottom of the symbol as the anchorpoint to get the same result. However, doing that, my symbols are way apart (see qgis_symbol_legend_anchorpoint_bottom.jpg) which seems wrong, or at least strongly counterintuitive to me.

Is this a bug, or do I misunderstand the logic of the anchorpoints ?

Moritz