public class Point3D {
    float x, y, z;

    public Point3D() {
    }

    public Point3D(float xval, float yval, float zval) {
        x = xval;
        y = yval;
        z = zval;
    }
    
    public Point3D(Point3D p) {
        copy(p);
    }
    
    public void copy(Point3D p) {
        x = p.x;
        y = p.y;
        z = p.z;
    }
    public void normalize() {
      float length = (float) Math.sqrt(x*x + y*y + z*z);
      x = x/length;
      y = y/length;
      z = z/length;
    }
}