Lively Kernel Tutorial: (6) Creating, Duplicating and Removing Objects
You can create, duplicate and remove objects using the operations found
in the popup menus. For instance, to duplicate the green ellipse in
the demo world, choose the "duplicate" item from its popup menu,
and then drag the copy to the desired position.
Correspondingly, to remove an object, choose the "remove" item
from the popup menu of the object.
To create entirely new objects from scratch, choose the "new object..."
item from the popup menu of the world.
Notes:
You can duplicate and remove composite objects by applying the "duplicate"
or "remove" menu operation to the bottommost object in the composite.
You can duplicate or remove the contents of a selection tray as well.
You can "tear" a copy of an object or composite object also by keeping
the Shift key down while clicking and dragging an object.
Try it yourself! Copy the green ellipse by choosing the
"duplicate" operation from its popup menu. Once you have successfully
copied the object, try removing the copy by using the "remove" operation.
Additionally, try creating composite objects by glueing multiple objects
together, and then copying and removing them.