Browse Prior Art Database

Updating Display

IP.com Disclosure Number: IPCOM000038158D
Original Publication Date: 1989-Dec-01
Included in the Prior Art Database: 2005-Jan-31
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Pekowski, R: AUTHOR [+2]

Abstract

Disclosed is a programming concept which reduces the need to update the entire display, instead updating only the area that changed.

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Updating Display

Disclosed is a programming concept which reduces the need to update the entire display, instead updating only the area that changed.

When less than the entire display is updated, an algorithm has been employed to determine what portion of the display has changed.

Variables called "min" and "max" are used. Initially, "max" is set to 0 and "min" is set to "1919". A routine is passed the current "offset". If the "offset" is less than "min", "min" is assigned the new "offset". Also, if the "offset" is greater than "max", "max" is assigned the "offset".

Eventually, when the time comes to update the display, a check is performed to see if "min" and "max" are different from their initial settings. If so, the starting offset for the update is calculated using "min". "Min" and "max" are used to compute a length for the update. The update takes place.

"Min" and "max" are reset to their initial values after the display update is completed.

Disclosed anonymously.

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