<p>A display system which is used as the input-output terminal of a data processing system which may be used for concurrent processing of application. Each application may have a viewport on the display screen and viewports may overlap. In order to write to low priority viewports without disturbing data displayed in those of a higher priority a mask buffer is used to prevent overwritting of high priority viewports.</p>
申请公布号
EP0145817(A1)
申请公布日期
1985.06.26
申请号
EP19830307697
申请日期
1983.12.19
申请人
INTERNATIONAL BUSINESS MACHINES CORPORATION
发明人
IMPEY, ALAN A.;POWELL, COLIN V.;SIMMONS, JOHN;EASTON, COLIN J.