Under layers in QGIS shapefile polygon layers always seem to be denoted by right angled polygons which translates to the map legend in Composer. Is there any way to change the outline to a more representative shape, i.e. lakes don't normally have right angles.
ArcGIS has a feature under the legend options to substitute the symbol being used in the layer with a preferred symbol, e.g. square to rounded or "blob" shaped. I'm after a similar feature in QGIS.