XmGetVisibility — A function that determines if a widget is visible "XmGetVisibility"

XmGetVisibility  returns  the visibility state of the specified widget.  It checks to see if some part of
       the widget's rectangular area is unobscured by the widget's ancestors,  or  some  part  of  the  widget's
       rectangular  area  is  inside  the work window (but possibly outside the clip window) of a ScrolledWindow
       whose XmNscrollingPolicy is XmAUTOMATIC and whose XmNtraverseObscuredCallback is not NULL.

       XmGetVisibility does not check to see if widget is obscured  by  its  siblings  or  by  siblings  of  its
       ancestors. Consequently, XmGetVisibility returns XmVISIBILITY_UNOBSCURED for widgets which are completely
       or partially covered by one or more siblings of widget by one or more siblings of ancestors of widget.

       When  a  widget  which is unrealized is being queried, it is indicated that the widget is fully obscured.
       If an application unmaps a widget that has its XmNmappedWhenManaged resource  set  to  True,  the  return
       value  is  undefined.  When a widget which is unmanaged is being queried, it is indicated that the widget
       is fully obscured.

       widget    Specifies the ID of the widget

XmGetVisibility — A function that determines if a widget is visible "XmGetVisibility"

XmIsTraversable(3), XmManager(3), and XmProcessTraversal(3).

                                                                                              XmGetVisibility(3)

       Returns one of the following values:

       XmVISIBILITY_UNOBSCURED
                 Indicates that the widget is mapped, not obscured, and is completely visible on the screen.

       XmVISIBILITY_PARTIALLY_OBSCURED
                 Indicates that the widget is mapped, and is not completely visible  on  the  screen  (partially
                 obscured).

       XmVISIBILITY_FULLY_OBSCURED
                 Indicates that the widget is not at all visible on the screen.

       #include <Xm/Xm.h>
       XmVisibilityXmGetVisibility(
       Widgetwidget);