Do we need an AthensCanvas>>#isVisible:�� ?
fullDrawOnSpartaCanvas: aCanvas
�� ��(self isVisibleOnCanvas: aCanvas)
�� ifFalse: [ ^ self ].
�� �� �� �� . . .��
Even if it would not speed up extent calculations, I would prefer too, to have EllipsePath, PolygonPath, ..., It is much more convenient to work with explicit classes than to define everything with a Path, even
if everything is just a Path :-)