| 摘要 |
PURPOSE:To completely eliminate the omission of plotting points by synthesizing control signals produced from a reduction process carried out by an OR circuit based on tilt components of a straight line and another reduction process using coordinate updating information on the generation of circles when an ellipse is plotted with reduction of a circle. CONSTITUTION:A signal received from a straight line generating circuit 10 gives a request to a coordinate replacement circuit 30 to update the coordinates in the direction of the short axis of an ellipse. While the output signal of a circle generating circuit 20 gives a request to the circuit 30 to update the coordinates in the direction of the long axis of the ellipse. Thus the circuit 30 performs the replacement of coordinates according to said requests respectively. Then an OR circuit 40 transmits the OR signal of each coordinate replacement request and controls the coordinate output of the circuit 30. As a result, the omission of the drawing points caused when an ellipse is drawn with reduction of a circle can be completed avoided with use of the coordinate replacement information on generation of circles as well as a reduction process carried out based on the tilt component of a straight line. |
