public java.awt.geom.GeneralPath appendPath(java.awt.geom.GeneralPath path) {
// number of curves to approximate the arc
int nSeg = (int) ceil(abs(angleExtent) / (PI / 2));
nSeg = min(nSeg, 4);
// angular extent of each curve
double ext = angleExtent / nSeg;
// compute coefficient
double k = btan(abs(ext));
for (int i = 0; i < nSeg; i++) {
// position of the two extremities
double ti0 = abs(i * ext);
double ti1 = abs((i + 1) * ext);
// extremity points
Point2D p1 = this.point(ti0);
Point2D p2 = this.point(ti1);
// tangent vectors, multiplied by appropriate coefficient
Vector2D v1 = this.tangent(ti0).times(k);
Vector2D v2 = this.tangent(ti1).times(k);
// append a cubic curve to the path
path.curveTo(
p1.x() + v1.x(), p1.y() + v1.y(), p2.x() - v2.x(), p2.y() - v2.y(), p2.x(), p2.y());
}
return path;
}
