| 摘要 |
PURPOSE:To easily obtain an optional shape at a high speed just by adding a view port area memory by synthesizing the display data causing a clipping operation and the data showing the area prescribed the view port area memory and writing this synthetic data to a display refresh memory. CONSTITUTION:The inside and outside area values of a view port area memory A14 are set at '1' and '0' respectively and stored previously in a view port area memory A13 in the form of the information equivalent to the shape of the port A14. While a view point area memory B15 stores the information equivalent to the shape of a view port B16 in the same way. In such a way, a picture is obtained by clipping the synthetic display data of both display data A and B via both view ports 14 and 16 having a synthetic shape of both view port area memories A and B and displayed. |
