org.orekit.bodies

Class Ellipsoid

java.lang.Object

org.orekit.bodies.Ellipsoid

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

OneAxisEllipsoid

public class Ellipsoid
extends Object
implements Serializable

Modeling of a general three-axes ellipsoid.

Since:

7.0

Author:

Luc Maisonobe

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Ellipsoid(Frame frame, double a, double b, double c) Simple constructor.

Method Summary

Modifier and Type	Method and Description
double	getA() Get the length of the first semi-axis.
double	getB() Get the length of the second semi-axis.
double	getC() Get the length of the third semi-axis.
Frame	getFrame() Get the ellipsoid central frame.
Ellipse	getPlaneSection(Vector3D planePoint, Vector3D planeNormal) Compute the 2D ellipse at the intersection of the 3D ellipsoid and a plane.
boolean	isInside(Vector3D point) Check if a point is inside the ellipsoid.
Vector3D	pointOnLimb(Vector3D observer, Vector3D outside) Find a point on ellipsoid limb, as seen by an external observer.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Ellipsoid

public Ellipsoid(Frame frame,
                 double a,
                 double b,
                 double c)

Simple constructor.

Parameters:

frame - at the ellipsoid center, aligned with principal axes

a - first semi-axis length

b - second semi-axis length

c - third semi-axis length

Method Detail

getA

public double getA()

Get the length of the first semi-axis.

Returns:

length of the first semi-axis (m)

getB

public double getB()

Get the length of the second semi-axis.

Returns:

length of the second semi-axis (m)

getC

public double getC()

Get the length of the third semi-axis.

Returns:

length of the third semi-axis (m)

getFrame

public Frame getFrame()

Get the ellipsoid central frame.

Returns:

ellipsoid central frame

isInside

public boolean isInside(Vector3D point)

Check if a point is inside the ellipsoid.

Parameters:

point - point to check, in the ellipsoid frame

Returns:

true if the point is inside the ellipsoid (or exactly on ellipsoid surface)

Since:

7.1

getPlaneSection

public Ellipse getPlaneSection(Vector3D planePoint,
                               Vector3D planeNormal)
                        throws MathRuntimeException

Compute the 2D ellipse at the intersection of the 3D ellipsoid and a plane.

Parameters:

planePoint - point belonging to the plane, in the ellipsoid frame

planeNormal - normal of the plane, in the ellipsoid frame

Returns:

plane section or null if there are no intersections

Throws:

MathRuntimeException - if the norm of planeNormal is null

pointOnLimb

public Vector3D pointOnLimb(Vector3D observer,
                            Vector3D outside)
                     throws OrekitException,
                            MathRuntimeException

Find a point on ellipsoid limb, as seen by an external observer.

Parameters:

observer - observer position in ellipsoid frame

outside - point outside ellipsoid in ellipsoid frame, defining the phase around limb

Returns:

point on ellipsoid limb

Throws:

OrekitException - if the observer is inside the ellipsoid

MathRuntimeException - if ellipsoid center, observer and outside points are aligned

Since:

7.1