Abstract: A view system is provided for each application program in a computer system in order to display application-generated information on a display. To increase graphic speed, the view system transfers graphic information directly into the screen buffer into a screen buffer area defined by a visible area definition. The view system provides support for minimal recomputation required for a correct display of data in several views when one view is changed. First, the view system generates an update request each time a change is made to one view, but the update request is only forwarded to those views which are affected by the change. Second, update requests are collected over a period of time and used to determine an invalid area caused by all of the requests and this latter invalid area is used to update each affected view.

Abstract: A view system is disclosed which provides support a mechanism to provide a multitask-safe wrapper or objects which are not multitask safe. This mechanism makes it possible to use objects that are not task-safe in a multitasking environment without modifying or understanding the internal workings of the said objects. This mechanism is not view system-specific, but is provided and used by the view system to support such behavior.