Viewport - scrollable view

SYNOPSIS

       #include <InterViews/viewport.h>

DESCRIPTION

       Viewport  is  a  subclass  of MonoScene that allocates its
       component exactly as much space as  it  wants  (determined
       from  its shape).  This space will be clipped to the view-
       port's size and the viewport maintains  a  perspective  to
       adjust  the portion of the component that is actually dis-
       played.  If the component is smaller than  the  viewport's
       canvas, then the viewport background will be filled with a
       light gray pattern.

PUBLIC OPERATIONS

       Viewport(Interactor* = nil, Alignment = Center)
              Construct a new viewport.  If the interactor is not
              nil,  it  is  inserted as the viewport's component.
              The second parameter determines where the component
              is placed relative to the viewport.

       Insert(Interactor*)
              Set the component interactor.

       void Change(Interactor*)
              A  viewport  does  not propagate changes.  Thus, if
              the component's shape changes the  viewport  simply
              resizes the component according to the new shape.

       void Remove(Interactor*)
              Take out the component interactor.

       virtual void Adjust(Perspective&)
              Change the viewport's perspective to the given one.
              This operation will cause the desired area  of  the
              component to be drawn.

       void AdjustTo(float px, float py, float zx, float zy)
       void AdjustBy(float dpx, float dpy, float dzx, float dzy)
       void ScrollTo(float px, float py)
       void ScrollXTo(float px)
       void ScrollYTo(float py)
       void ScrollBy(float dpx, float dpy)
       void ScrollXBy(float dpx)
       void ScrollYBy(float dpy)
       void ZoomTo(float zx, float zy)
       void ZoomXTo(float zx)
       void ZoomYTo(float zy)
       void ZoomBy(float dzx, float dzy)
       void ZoomXBy(float dzx)
       void ZoomYBy(float dzy)

       float XPos()
       float YPos()
       float XMag()
       float YMag()
              Short-hand for  retrieving  information  about  the
              current perspective.

SEE ALSO

       Perspective(3I), Scene(3I), Shape(3I)