Patent · US Expired

Method and apparatus for determining boundaries of graphic regions

US4788538A · kind A · utility

66Cited by
4References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 24, 1987
Grant dateNov 29, 1988
Priority date
Expiry dateApr 24, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06T2207/20101
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

The present invention provides apparatus and methods for determining the boundaries of arbitrarily shaped regions on a computer display system having a central processing unit (CPU). The CPU is coupled to a display having a plurality of selectively enabled and disabled display elements arranged in a matrix, whereby each display element is identified by a unique X,Y address. A memory coupled to the CPU includes a plurality of memory cells, wherein the cells correspond to a display element on the display. An initial X,Y address is selected on the display by a user employing a cursor control to identify an area on the display where the boundaries of a region are to be determined. The initial X,Y address selected by the user is defined as a seed cell. The CPU determines if the initial seed cell corresponds to a disabled memory cell and blank (disabled) display element, and in such event increments the initial X,Y address to search outwardly a predetermined maximum distance to adjacent memory cells until an enabled (non-blank) cell is located. This enabled cell is set as a new seed cell. The CPU then searches radially outward in M directions from the new seed cells X,Y address for N con…

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