Software Structure for Display Management Systems

Display management software usually provides support for: creating displays on a CRT (cathode ray tube) or other output device; handling user inputs from keyboards, light-pens, and other input devices; and communicating with an application program in terms of these outputs and inputs. We propose a design for a family of display management systems which provide device-independent, high-level support for applications programming. The design involves structuring the display management software as a set of modules, with three levels of interfaces. The key features of this design include: 1) separation of display specifications from the actual data to be displayed; 2) structured output and input specifications; 3) asynchronous, message passing inter-faces; and 4) a software structure based on hiding details of data structures, algorithms and device orders.