Patent · US Expired

Undo feature for a graphical programming system

US5990906A · kind A · utility

67Cited by
3References
33Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 19, 1997
Grant dateNov 23, 1999
Priority date
Expiry dateAug 19, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F8/34
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

An Undo/Redo feature for a graphical programming system which minimizes the required data storage. The graphical programming system includes a plurality of interconnected objects, including fixed size objects and variable size objects. A variable size object is an object which typically changes in size, i.e., grows or shrinks, in response to user modification, whereas fixed size objects do not change in size. When an object is modified by the user, the method of the present invention stores a backup copy for undo purposes. For modification of an object, the backup is performed differently depending on whether the object is a variable size object or a fixed size object. For a variable size object, the method stores the original object as the previous object in the backup list, and the method stores a copy of the original object as the current object in the backup list. For a fixed size object, the method stores a copy of the original object as the previous object in the backup list, and the method stores the original object as the current object in the backup list. For a fixed size object, the original object thus remains as the current or foreground object in the graphical program.…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.