| 摘要 |
PURPOSE:To reduce the size of hardware and to rapidly set up parameters by providing the segment plotting parameter setting-up circuit with a means for finding out a difference function value relating to the X and Y coordinate values of a segment to be plotted, a storage means and a means for finding out a parameter. CONSTITUTION:A differentiator 210 finds out a difference between the X coordinate X2 of a start point and the X coordinate X6 of an end point and an absolute value circuit 212 outputs an absolute value X=¦Xe - Xc¦. A 1-bit code bO is outputted from the differentiator 210 and the code b0 is '0' when X3>=Xs or '1' when Xe<=Xs. The pattern of a segment to be plotted is sorted to eight areas around the start point of plotting. Out of three bit codes outputted from an area code calculating circuit 120, the bits b1, b0 are outputs from an X differential absolute value circuit 212 and a Y differential absolute value circuit 213 and the bit b2 is obtained by comparing the outputs X, Y of differential absolute circuits 100, 110 and goes '0' when X>= Y or '1' when X< Y. When a segment plotting parameter is set up by using the area codes of segments, the hardware size can be reduced and the setting up speed can be improved. |
