(19)
(11) EP 0 247 711 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
09.08.1989 Bulletin 1989/32

(43) Date of publication A2:
02.12.1987 Bulletin 1987/49

(21) Application number: 87302887.2

(22) Date of filing: 02.04.1987
(51) International Patent Classification (IPC)4: G09G 1/10, G09G 1/14
(84) Designated Contracting States:
AT BE CH DE ES FR GB GR IT LI LU NL SE

(30) Priority: 30.05.1986 US 868445

(71) Applicant: PRIME COMPUTER, INC.
Natick Massachusetts 01760 (US)

(72) Inventor:
  • Keller, James A., Jr.
    Cambridge Massachusetts 02139 (US)

(74) Representative: Blatchford, William Michael 
Withers & Rogers 4 Dyer's Buildings Holborn
London EC1N 2JT
London EC1N 2JT (GB)


(56) References cited: : 
   
       


    (54) Line display apparatus and method


    (57) A method and apparatus for providing a faster graphical representation of lines to be displayed from their endpoint data either uses the natural symmetry of the line or imposes a forced symmetry upon the line to reduce the processing time required for generating each of the points representing the line. The order in which the endpoints are provided to the apparatus does not change the resulting representation. An iterative process, starting at centers of a partitioned line, incrementally determines the positions of the pixels which best, within the concept of the invention, fit the actual line being represented.






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