Processing: Creative Coding and Computational Art

Next is an interactive example that illustrates this interpolation process as a simple geometric
progression. The sketch (shown in Figure 7-27) plots a quadratic curve using two
anchor points and a single control point, and interpolates between these three points.
Technically, the area defined by the control and anchor points is called a convex hull. Each
time you click within the example, another iteration occurs, dividing the previous segments
in half and plotting the path, slowly approximating the curve.
/* Interpolating a Bézier
curve within a convex hull
**************************
Click the screen a couple of
times to iteratively generate
the curve*/
int startingPoints = 3;
// Uses Java's Point class
Point[] bezier = new Point[startingPoints];
void setup(){
size(600, 400);
background(255);
smooth();
// create external bezier
bezier[0] = new Point(10, 390);
bezier[1] = new Point(300, 10);
bezier[2] = new Point(590, 390);
// plot initial convex hull
plot(bezier);
}
Point[] plotBezier(Point[] pts){
Point[] path = new Point[pts.length+1];
path[0] = pts[0];
for (int i=1; i