Examples with Vector2D org.hipparchus.geometry.euclidean.twod.Vector2D used on opensource projects

Example 6 with Vector2D

use of org.hipparchus.geometry.euclidean.twod.Vector2D in project Orekit by CS-SI.

the class OneAxisEllipsoidTest method transformOldIterative.

/**
 * Transform a Cartesian point to a surface-relative point.
 * <p>
 * This method was the implementation used in the main Orekit library
 * as of version 8.0. It has been replaced as of 9.0 with a new version
 * using faster iterations, so it is now used only as a test reference
 * with an implementation which is different from the one in the main library.
 * </p>
 * @param point Cartesian point
 * @param frame frame in which Cartesian point is expressed
 * @param date date of the computation (used for frames conversions)
 * @return point at the same location but as a surface-relative point
 * @exception OrekitException if point cannot be converted to body frame
 */
private GeodeticPoint transformOldIterative(final OneAxisEllipsoid model, final Vector3D point, final Frame frame, final AbsoluteDate date) throws OrekitException {
    // transform point to body frame
    final Vector3D pointInBodyFrame = frame.getTransformTo(model.getBodyFrame(), date).transformPosition(point);
    final double r2 = pointInBodyFrame.getX() * pointInBodyFrame.getX() + pointInBodyFrame.getY() * pointInBodyFrame.getY();
    final double r = FastMath.sqrt(r2);
    final double z = pointInBodyFrame.getZ();
    // set up the 2D meridian ellipse
    final Ellipse meridian = new Ellipse(Vector3D.ZERO, new Vector3D(pointInBodyFrame.getX() / r, pointInBodyFrame.getY() / r, 0), Vector3D.PLUS_K, model.getA(), model.getC(), model.getBodyFrame());
    // project point on the 2D meridian ellipse
    final Vector2D ellipsePoint = meridian.projectToEllipse(new Vector2D(r, z));
    // relative position of test point with respect to its ellipse sub-point
    final double dr = r - ellipsePoint.getX();
    final double dz = z - ellipsePoint.getY();
    final double ae2 = model.getA() * model.getA();
    final double f = model.getFlattening();
    final double g = 1.0 - f;
    final double g2 = g * g;
    final double insideIfNegative = g2 * (r2 - ae2) + z * z;
    return new GeodeticPoint(FastMath.atan2(ellipsePoint.getY(), g2 * ellipsePoint.getX()), FastMath.atan2(pointInBodyFrame.getY(), pointInBodyFrame.getX()), FastMath.copySign(FastMath.hypot(dr, dz), insideIfNegative));
}