ELLIPSE DRAWING DEVICE AND RECORDING MEDIUM RECORDING ELLIPSE DRAWING PROGRAM

摘要

PROBLEM TO BE SOLVED: To draw a tilted ellipse by high operating performance by drawing the ellipse on a screen based on a normally standing square circumscribing a reference ellipse shown on the screen and a set inclination. ;SOLUTION: An elliptic drawing (reference ellipse) 50 on a read-in base paper is displayed on the screen 5A of a display means. A cross cursor on the screen 5A is operated to draw a normally placed rectangle 51 to be in contact with the drawing 50. The vertical and horizontal directions of the rectangle 51 are detected and contrasted to decide a contrast value and when the contrast value is smaller than a set value (1), this processing operation is finished. When the contrast value is larger than the set value, the normally placed rectangle is regarded as a normally placed square. The length of the normally placed square is detected. Next, the normally placed ellipse circumscribed about the normally placed square is prepared and is superposed to the reference ellipse. At this time, inclination for obtaining the ratio of the linger diameter and the shorter diameter of the normally placed ellipse is designated. An ellipse is prepared so as to be inscribed in the normally placed square according to the inclination and the cross cursor.;COPYRIGHT: (C)1999,JPO