A graphic object is said to be zoomable if
its bounding box follows the zoom level. Otherwise, the object is
nonzoomable. (To know whether a graphic object is zoomable, use
its boolean zoomable() method, or check its documentation.)
If all the nodes and links of an IlvGrapher object are zoomable graphic
objects, a layout obtained on the basis of the graph geometry in
manager coordinates will look the same for any value of the
transformer used for the display. Simply speaking, the drawing of
the graph will just be zoomed, or translated.
When at least one nonzoomable graphic object is used as a node in
an
IlvGrapher
, the geometry of the grapher in manager coordinates can no longer
be used. When drawn with different transformer values (for
instance, at different zoom levels), the same
IlvGrapher
can look very different.
When a grapher contains nonzoomable graphic objects, it may not be
appropriate to deal with the geometry of the IlvGrapher based on the bounding boxes of
the graph objects systematically computed for an identity
transformer (manager coordinates). To ensure that the drawing of
the laid-out graph is always correct, even when nonzoomable
graphic objects are present, the transformer used for the display
must be considered.