| 摘要 |
PURPOSE:To perform the plotting of a circle with short radius at high speed by performing pattern plotting by holding and storing plural pieces of pattern data of the circle whose inside is painted out. CONSTITUTION:A circle plotting control means 2 decides whether or not the circle with radius for which plotting is designated from an input means 1 is registered on a pattern storage means 6, and starts up a line segment development processing means 3 when it is not registered. The means 3 approximates a circumference from a designated radius by a polygon, and develops it to a line segment string, and starts up a paint-out means 4. Thereby, a painted-out circle is plotted on a frame buffer 7, and is displayed on a display device 8. Meanwhile, when circle data with designated radius exists on the means 6, corresponding data is read out by a pattern display processing means 5, and the circle is plotted on the buffer 7. Therefore, it is possible to plot the circle with short radius at high speed by holding and storing plural circles with short radii less than six dots in the means 6. |
