/*
* (non-Javadoc)
*
* @see math.geom2d.Shape2D#signedDistance(math.geom2d.Point2D)
*/
public double signedDistance(double x, double y) {
boolean direct = angleExtent >= 0;
double dist = distance(x, y);
Point2D point = new Point2D(x, y);
boolean inside = ellipse.isInside(point);
if (inside) return angleExtent > 0 ? -dist : dist;
Point2D p1 = point(startAngle);
double endAngle = startAngle + angleExtent;
Point2D p2 = point(endAngle);
boolean onLeft = (new StraightLine2D(p1, p2)).isInside(point);
if (direct && !onLeft) return dist;
if (!direct && onLeft) return -dist;
Ray2D ray = new Ray2D(p1, -sin(startAngle), cos(startAngle));
boolean left1 = ray.isInside(point);
if (direct && !left1) return dist;
if (!direct && left1) return -dist;
ray = new Ray2D(p2, -sin(endAngle), cos(endAngle));
boolean left2 = ray.isInside(point);
if (direct && !left2) return dist;
if (!direct && left2) return -dist;
if (direct) return -dist;
else return dist;
}
/*
* (non-Javadoc)
*
* @see math.geom2d.OrientedCurve2D#windingAngle(math.geom2d.Point2D)
*/
public double windingAngle(Point2D point) {
Point2D p1 = point(0);
Point2D p2 = point(abs(angleExtent));
// compute angle of point with extreme points
double angle1 = Angle2D.horizontalAngle(point, p1);
double angle2 = Angle2D.horizontalAngle(point, p2);
// test on which 'side' of the arc the point lie
boolean b1 = (new StraightLine2D(p1, p2)).isInside(point);
boolean b2 = ellipse.isInside(point);
if (angleExtent > 0) {
if (b1 || b2) { // inside of ellipse arc
if (angle2 > angle1) return angle2 - angle1;
else return 2 * PI - angle1 + angle2;
} else { // outside of ellipse arc
if (angle2 > angle1) return angle2 - angle1 - 2 * PI;
else return angle2 - angle1;
}
} else {
if (!b1 || b2) {
if (angle1 > angle2) return angle2 - angle1;
else return angle2 - angle1 - 2 * PI;
} else {
if (angle1 > angle2) return angle2 - angle1 + 2 * PI;
else return angle2 - angle1;
}
}
}
