/** 3D location
 * @author: Phil Gage
 */
class Point /* extends Vector3 */ {

    public double x, y, z;

    Point () {
        this.x = 0.0;
        this.y = 0.0;
        this.z = 0.0;
    }

    Point (Point p) {
        this.x = p.x;
        this.y = p.y;
        this.z = p.z;
    }

    Point (double x, double y, double z) {
        this.x = x;
        this.y = y;
        this.z = z;
     }

    /** Copy a to this */
    public void set (Point a) {
        this.x = a.x;
        this.y = a.y;
        this.z = a.z;
    }

    /** Copy a to this */
    public void set (double x, double y, double z) {
        this.x = x;
        this.y = y;
        this.z = z;
    }

    public double dot (Vector3 v) {
        return x*v.x + y*v.y + z*v.z;
    }

    public Vector3 subtract (Point p) {
        return new Vector3 (x - p.x, y - p.y, z - p.z);
    }

    public double distance (Point p) {
        return Math.sqrt ((p.x-x)*(p.x-x) + (p.y-y)*(p.y-y) + (p.z-z)*(p.z-z));
    }

    public String toString () {
        return "Point x=" + x + " y=" + y + " z=" + z;
    }

}