Curve-generating device for visual display of symbols on a cathode-ray screen

摘要

The curve-generating device serves in particular to produce signals relating to a circular line from simple algorithms. The device comprises means for computing a parameter DELTA L defined by <IMAGE> where U is an elementary vector, theta is the angle at the center of a polygon of side U+ DELTA L circumscribed about the circle R, and processing logic circuits for determining the polar direction Pn of the plotted line according to the relation: <IMAGE> where DELTA n-1=1 in respect of xn-1>/=U and xn=xn-1+ DELTA Lx DELTA n-1-Ux DELTA n-1.