| 摘要 |
PROBLEM TO BE SOLVED: To shorten plotting time in the case of newly performing the plotting of a map. SOLUTION: Data in an already plotted area which is plotted in the area A of a video RAM is copied at a part of the area B, and plotting is performed in the remaining plotting area of the area B. In such a case, whether or not the data to be plotted such as a road, a background and a character is the data to be plotted only in a non-plotting area where the data in the already plotted area is copied is decided. When the data to be plotted is the data to be plotted only in the non-plotting area, the plotting is not executed. When the data to be plotted is the data to be plotted in the plotting area, the plotting according to the data is performed. |
