Bézier Circles and other shapes

While it is impossible to draw a circle with Bézier curves, it is quite possible to emulate one so well that, when viewed by human eyes, the drawing is indistinguishable from an actual circle. All you need to do is use the right value of the Bézier control points. This value is the radius of the circle multiplied by a constant known as the kappa. This book tells you the right value of the kappa, explains the psychological reason why it works, and offers the mathematical proof of the validity of the kappa. It will also show you how to use prime number multiples and fractions of the kappa to obtain other useful shapes.