| 摘要 |
<p>PURPOSE:To evade the reduction of processing speed even in case an undrawn area is picked up by omitting the redrawing actions in the case the drawing data are equal to 0 within a rectangular area where a pattern is picked up and then picking up the pattern when 1 is detected. CONSTITUTION:When a host computer sets a rectangular area at a window register 2 for pick-up a pattern, a drawing processor 1 reads out successively the words in the rectangular area. At the same time, a zero detecting part 4 decides whether all valid bits of the words are equal to '0' or not. If so, the processor 1 transmits a fact to the host computer that no pattern to be picked up is included in the rectangular area. Thus the redrawing action is omitted. In case a bit which is not equal to '0' is detected within the rectangular area, the processor 1 issues a request to the host computer to start a redrawing action for pick-up a pattern. Thus the pattern pick-up action is started.</p> |
