test drawing 2
This drawing uses groups. Groups allow specification of drawing properties
like fill or stroke colors which are then inherited by members of the group.
The circles on the left belong to a different group than the circles on the
right and so have different stroke colors.
test drawing 3
This drawing shows off the use of named references. The basic outline of the
"House" object is defined just once. It appears in different positions and with
different colors via reference to the named "House" object under different
enclosing contexts.