curves of any degree. According to Bézier, all curves can be defined by four control points
. Two control points are located at the beginning and end of a variable line, and two others, called curve support points, are located outside the line. The control points are called curve points or Bézier Points (BP), and the curve support points are called Bézier Curve Points (BCP).
ve The two curve support points are touch points that influence the curvature of the Bézier curves. They are decisive for the definition of the tangent vectors in the end points. With the two curve points at the line ends, the lines can be compressed and stretched. By dividing complex curves into individual curves, all polygonal curves and surfaces can be reproduced. Bézier curves belong to the spline cur ves and are also used in Postscript for the fonts.