Rational C1 Bezier Spline Applet
DIRECTIONS: In this applet, you create a rational
C1 Bezier spline by placing control points pi = (xi,yi)
on the screen, which are stored as points in space as (1,xi,yi).
The weights λi are initially set as 1, and are
modified by using the A and Z keys. The A key decreases the weight
and the Z key increases the weight. The algorithm for creating
the composite rational Bezier curve proceeds by constructing a
C1 Bezier spline in space with control points
(λi,xi,yi) and then perspectively
projecting this curve onto the plane (1,ξ,η).