traints. (The constraints can also be changed at run-time.) How the system manages visible object geometry is discussed in <A HREF="VisClass_e.htm#16842"> Geometry Management</A>
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The geometry manager, though extremely useful for non-overlapping objects, may not be sufficient for all the needs of a complex application. For an object to determine its own size and position, it has to handle some of the messages sent out by the geometry manager. You can also manually set the size and position of each 