If the layer has a superbitmap all the parts that are visible will be copied into the superbitmap. This is usually not done except when parts of a superbitmapped layer become hidden the visible parts are stored into the superbitmap.
INPUTS
l
pointer to superbitmapped layer
RESULT
The superbitmap will be synchronized with the visible part. The superbitmap attatched to the layer will be up-to-date with what's really in the layer.