Edward Y Kwong

US Patent:

48398284, Jun 13, 1989

Filed:

Jan 21, 1986

Appl. No.:

6/821102

Inventors:

Matthew Elsner - Woodstock NY
Yoshio Iida - Lake Katrine NY
Edward Y. Kwong - West Hurley NY
Omar M. Rahim - Rhinebeck NY

Assignee:

International Business Machines Corporation - Armonk NY

International Classification:

G06F 315

US Classification:

364518

Abstract:

A color graphic display having a read/write control system for a buffer memory therein. The invention provides Line-on-Line and Underpaint by way of a method which invleves reading the contents of a frame buffer storage location for which new pixel data is being provided, comparing those contents with data representing a display background characteristic or color, and if the result of the comparison is positive, storing the new pixel data in the frame buffer storage location. If the result of the comparison is negative, a selected data value different from the new pixel data is stored in the frame buffer storage location.