
. (Subclasses of the above classes may also be used.)</P>
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The visible object tree is displayed normally through a GenView object. The output of the GenView must be tied directly to the top node of the visible object tree; this is why the visible tree must be headed by a VisContent--only the VisContent has the methods to handle GenView messages.
<IMG SRC="VisClass_c_visAndGen.gif">

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The VisContent object may or may not do things other than manage the visible tree. For example, the content may d