gov.nasa.worldwind.globe

Class BasicGlobe

java.lang.Object

gov.nasa.worldwind.globe.BasicGlobe

All Implemented Interfaces:

Globe

Direct Known Subclasses:

GlobeWgs84

public class BasicGlobe
extends java.lang.Object
implements Globe

Generic ellipsoidal Globe enabling construction with standard ellipsoid values.

Constructor Summary

Constructors

Constructor and Description
BasicGlobe(double semiMajorAxis, double inverseFlattening, GeographicProjection projection) Constructs a generic Globe implementation with specified ellipsoid parameters.

Method Summary

Modifier and Type	Method and Description
Matrix4	cameraToCartesianTransform(Camera camera, Matrix4 result)
LookAt	cameraToLookAt(Camera camera, LookAt result)
Position	cartesianToGeographic(double x, double y, double z, Position result) Converts a Cartesian point to a geographic position.
Matrix4	cartesianToLocalTransform(double x, double y, double z, Matrix4 result)
Vec3	geographicToCartesian(double latitude, double longitude, double altitude, Vec3 result) Converts a geographic position to Cartesian coordinates.
float[]	geographicToCartesianGrid(Sector sector, int numLat, int numLon, double[] elevations, Vec3 origin, float[] result, int stride, int pos)
Vec3	geographicToCartesianNormal(double latitude, double longitude, Vec3 result)
Matrix4	geographicToCartesianTransform(double latitude, double longitude, double altitude, Matrix4 result)
double	getEccentricitySquared() Indicates the eccentricity squared parameter of the globe's ellipsoid.
double	getEquatorialRadius() Indicates the radius in meters of the globe's ellipsoid at the equator.
double	getPolarRadius() Indicates the radius in meters of the globe's ellipsoid at the poles.
GeographicProjection	getProjection() Indicates the geographic projection used by this globe.
double	getRadiusAt(double latitude, double longitude) Indicates the radius in meters of the globe's ellipsoid at a specified location.
Tessellator	getTessellator()
double	horizonDistance(double eyeAltitude) Indicates the distance to the globe's horizon from a specified eye altitude.
double	horizonDistance(double eyeAltitude, double objectAltitude) Indicates the distance to an object passing over the globe's horizon from a specified eye altitude.
boolean	intersect(Line line, Vec3 result) Computes the first intersection of this globe with a specified line.
Camera	lookAtToCamera(LookAt lookAt, Camera result)
Matrix4	lookAtToCartesianTransform(LookAt lookAt, Matrix4 result)
void	setProjection(GeographicProjection projection) Sets the geographic projection used by this globe.
void	setTessellator(Tessellator tessellator)

Methods inherited from class java.lang.Object

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

Constructor Detail

BasicGlobe

public BasicGlobe(double semiMajorAxis,
                  double inverseFlattening,
                  GeographicProjection projection)

Constructs a generic Globe implementation with specified ellipsoid parameters.

Parameters:

semiMajorAxis - one half of the globe's major axis, which runs through the center to opposite points on the equator

inverseFlattening - a measure of the ellipsoid's compression

projection - the geographic projection used by this globe, which specifies the Cartesian coordinate system

Throws:

java.lang.IllegalArgumentException - if either of the semi-major axis or the inverse flattening are less than or equal to zero, or if the projection is null

Method Detail

getEquatorialRadius

public double getEquatorialRadius()

Description copied from interface: Globe

Indicates the radius in meters of the globe's ellipsoid at the equator.

Specified by:

getEquatorialRadius in interface Globe

Returns:

the radius at the equator, in meters.

getPolarRadius

public double getPolarRadius()

Description copied from interface: Globe

Indicates the radius in meters of the globe's ellipsoid at the poles.

Specified by:

getPolarRadius in interface Globe

Returns:

the radius at the poles, in meters.

getRadiusAt

public double getRadiusAt(double latitude,
                          double longitude)

Description copied from interface: Globe

Indicates the radius in meters of the globe's ellipsoid at a specified location.

Specified by:

getRadiusAt in interface Globe

Parameters:

latitude - the location's latitude in degrees

longitude - the location's longitude in degrees

Returns:

the radius in meters of the globe's ellipsoid at the specified location

getEccentricitySquared

public double getEccentricitySquared()

Description copied from interface: Globe

Indicates the eccentricity squared parameter of the globe's ellipsoid. This is equivalent to 2*f - f*f, where f is the ellipsoid's flattening parameter.

Specified by:

getEccentricitySquared in interface Globe

Returns:

the eccentricity squared parameter of the globe's ellipsoid.

getProjection

public GeographicProjection getProjection()

Description copied from interface: Globe

Indicates the geographic projection used by this globe. The projection specifies this globe's Cartesian coordinate system.

Specified by:

getProjection in interface Globe

Returns:

the globe's projection

setProjection

public void setProjection(GeographicProjection projection)

Description copied from interface: Globe

Sets the geographic projection used by this globe. The projection specifies this globe's Cartesian coordinate system.

Specified by:

setProjection in interface Globe

Parameters:

projection - the projection to use

getTessellator

public Tessellator getTessellator()

Specified by:

getTessellator in interface Globe

Returns:

setTessellator

public void setTessellator(Tessellator tessellator)

Specified by:

setTessellator in interface Globe

geographicToCartesian

public Vec3 geographicToCartesian(double latitude,
                                  double longitude,
                                  double altitude,
                                  Vec3 result)

Description copied from interface: Globe

Converts a geographic position to Cartesian coordinates. This globe's projection specifies the Cartesian coordinate system.

Specified by:

geographicToCartesian in interface Globe

Parameters:

latitude - the position's latitude in degrees

longitude - the position's longitude in degrees

altitude - the position's altitude in meters

result - a pre-allocated Vec3 in which to store the computed X, Y and Z Cartesian coordinates

Returns:

the result argument, set to the computed Cartesian coordinates

geographicToCartesianNormal

public Vec3 geographicToCartesianNormal(double latitude,
                                        double longitude,
                                        Vec3 result)

Specified by:

geographicToCartesianNormal in interface Globe

Returns:

geographicToCartesianTransform

public Matrix4 geographicToCartesianTransform(double latitude,
                                              double longitude,
                                              double altitude,
                                              Matrix4 result)

Specified by:

geographicToCartesianTransform in interface Globe

Returns:

geographicToCartesianGrid

public float[] geographicToCartesianGrid(Sector sector,
                                         int numLat,
                                         int numLon,
                                         double[] elevations,
                                         Vec3 origin,
                                         float[] result,
                                         int stride,
                                         int pos)

Specified by:

geographicToCartesianGrid in interface Globe

Returns:

cartesianToGeographic

public Position cartesianToGeographic(double x,
                                      double y,
                                      double z,
                                      Position result)

Description copied from interface: Globe

Converts a Cartesian point to a geographic position. This globe's projection specifies the Cartesian coordinate system.

Specified by:

cartesianToGeographic in interface Globe

Parameters:

x - the Cartesian point's X component

y - the Cartesian point's Y component

z - the Cartesian point's Z component

result - a pre-allocated Position in which to store the computed geographic position

Returns:

the result argument, set to the computed geographic position

cartesianToLocalTransform

public Matrix4 cartesianToLocalTransform(double x,
                                         double y,
                                         double z,
                                         Matrix4 result)

Specified by:

cartesianToLocalTransform in interface Globe

cameraToCartesianTransform

public Matrix4 cameraToCartesianTransform(Camera camera,
                                          Matrix4 result)

Specified by:

cameraToCartesianTransform in interface Globe

cameraToLookAt

public LookAt cameraToLookAt(Camera camera,
                             LookAt result)

Specified by:

cameraToLookAt in interface Globe

lookAtToCartesianTransform

public Matrix4 lookAtToCartesianTransform(LookAt lookAt,
                                          Matrix4 result)

Specified by:

lookAtToCartesianTransform in interface Globe

lookAtToCamera

public Camera lookAtToCamera(LookAt lookAt,
                             Camera result)

Specified by:

lookAtToCamera in interface Globe

horizonDistance

public double horizonDistance(double eyeAltitude)

Description copied from interface: Globe

Indicates the distance to the globe's horizon from a specified eye altitude. The result of this method is undefined if the eye altitude is negative.

Specified by:

horizonDistance in interface Globe

Parameters:

eyeAltitude - the eye altitude in meters

Returns:

the distance in meters

horizonDistance

public double horizonDistance(double eyeAltitude,
                              double objectAltitude)

Description copied from interface: Globe

Indicates the distance to an object passing over the globe's horizon from a specified eye altitude. This computes the distance at which a point at objectAltitude is on the threshold of passing beyond the globe's horizon, and would thereafter be occluded by the globe. The result of this method is undefined if either altitude is negative.

Specified by:

horizonDistance in interface Globe

Parameters:

eyeAltitude - the eye altitude in meters

objectAltitude - the object altitude in meters

Returns:

the distance in meters

intersect

public boolean intersect(Line line,
                         Vec3 result)

Description copied from interface: Globe

Computes the first intersection of this globe with a specified line. The line is interpreted as a ray; intersection points behind the line's origin are ignored.

Specified by:

intersect in interface Globe

Parameters:

line - the line to intersect with this globe

result - a pre-allocated Vec3 in which to return the computed point

Returns:

true if the ray intersects the globe, otherwise false