Image Number 19 for United States Patent #5737559.
An object-oriented view system which displays a plurality of separate view areas on a computer display screen allows hierarchically arranged overlapping view areas. The views are controlled by a view hierarchy object which includes a tree structure of information associated with every view. The tree structure has multiple branches and supports recursive view support for views within views. The views are drawn directly in the screen buffer by application programs which retrieve view definition information from the view hierarchy object. The view hierarchy makes it possible for views of uncertain origin or implementation to function polymorphically within a display hierarchy.