| 摘要 |
PURPOSE:To draw a smooth curve at a high speed, by generating quadratic curve signal in non-parametrically based on the primary differential coefficients fx and fy in the directions of X and Y at a point (x, y). CONSTITUTION:The primary differential coefficients in the directions of X and Y at a point P (x,y) are designated as fx and fy. The magnitude and sign of the coefficients fx and fy are compared with each other. Hereupon, a circle on which the point P lies is considered, and it is judged that in which part does the point P lie when the circule is equally divided into eight. Then, two points which are to be selected next by the point P are selected from each part. New locations G0 and G1 of the point P when each point is selected is obtained. The smaller value among those values,¦G0¦and¦G1¦, is used as the true next location. These processings can be realized when an arithmetic unit controlled by a microcomputer and plural data register are used. |
