gov.nasa.worldwind.globes
Interface Globe

All Superinterfaces:

AVList, EventListener, Extent, MessageListener, PropertyChangeListener, WWObject

All Known Implementing Classes:

Earth, EarthFlat, EllipsoidalGlobe, FlatGlobe

public interface Globe
extends WWObject, Extent

Represents a planet's shape and terrain. A globe may be associated with an ElevationModel that provides elevations for geographic positions on the surface of the globe. Globe provides methods for converting geographic positions (latitude, longitude, and elevation) to cartesian coordinates, and for converting cartesian to geographic. The origin and orientation of the cartesian coordinate system are determined by implementations of this interface.

Method Summary

Matrix	computeModelCoordinateOriginTransform(Angle latitude, Angle longitude, double metersElevation)
Matrix	computeModelCoordinateOriginTransform(Position position)
Vec4	computeNorthPointingTangentAtLocation(Angle latitude, Angle longitude) Computes a vector tangent to this globe and pointing toward the north pole.
Vec4	computePointFromLocation(LatLon location) Computes a cartesian point from a geographic location on the surface of this globe.
Vec4	computePointFromPosition(Angle latitude, Angle longitude, double metersElevation) Computes a cartesian point from a latitude, longitude, and elevation.
Vec4	computePointFromPosition(LatLon latLon, double metersElevation) Computes a cartesian point from a geographic location and elevation.
Vec4	computePointFromPosition(Position position) Computes a cartesian point from a geographic position.
Position	computePositionFromPoint(Vec4 point) Computes the geographic position of a point in cartesian coordinates.
Vec4	computeSurfaceNormalAtLocation(Angle latitude, Angle longitude) Computes a vector perpendicular to the surface of this globe.
Vec4	computeSurfaceNormalAtPoint(Vec4 point) Computes a vector perpendicular to the surface of this globe, at a cartesian point.
Matrix	computeSurfaceOrientationAtPosition(Angle latitude, Angle longitude, double metersElevation) Returns the cartesian transform Matrix that maps model coordinates to a local coordinate system at (latitude, longitude, metersElevation).
Matrix	computeSurfaceOrientationAtPosition(Position position) Returns the cartesian transform Matrix that maps model coordinates to a local coordinate system at (latitude, longitude, metersElevation).
double	getEccentricitySquared() Indicates the square of this globe's eccentricity.
double	getElevation(Angle latitude, Angle longitude) Indicates the elevation at a specified location.
ElevationModel	getElevationModel() Indicates this globe's elevation model.
double	getElevations(Sector sector, List<? extends LatLon> latlons, double targetResolution, double[] elevations) Indicates the elevations of a collection of locations.
double	getEquatorialRadius() Indicates the radius of the globe at the equator, in meters.
Extent	getExtent() Indicates the spatial volume contained by this globe.
GlobeStateKey	getGlobeStateKey() Returns a typed state key identifying this globe's current configuration.
GlobeStateKey	getGlobeStateKey(DrawContext dc) Returns a typed state key identifying this globe's current configuration.
Position	getIntersectionPosition(Line line) Computes the intersections of this globe and a line.
double	getMaxElevation() Indicates the maximum elevation on this globe, in meters.
double	getMaximumRadius() Indicates the maximum radius on the globe.
double[]	getMinAndMaxElevations(Angle latitude, Angle longitude) Returns the minimum and maximum elevations at a specified location on this Globe.
double[]	getMinAndMaxElevations(Sector sector) Returns the minimum and maximum elevations within a specified sector on this Globe.
double	getMinElevation() Indicates the minimum elevation on this globe, in meters.
double	getPolarRadius() Indicates the radius of the globe at the poles, in meters.
double	getRadiusAt(Angle latitude, Angle longitude) Indicates the radius of the globe at a location.
double	getRadiusAt(LatLon latLon) Indicates this globe's radius at a specified location.
Object	getStateKey(DrawContext dc) Returns a state key identifying this globe's current configuration.
Tessellator	getTessellator() Returns this globe's current tessellator.
Intersection[]	intersect(Line line, double altitude) Intersects a specified line with this globe.
Intersection[]	intersect(Triangle triangle, double altitude) Intersects a specified triangle with the globe.
boolean	isPointAboveElevation(Vec4 point, double elevation) Determines whether a point is above a given elevation.
void	setElevationModel(ElevationModel elevationModel) Specifies this globe's elevation model.
void	setTessellator(Tessellator tessellator) Specifies this globe's tessellator.
SectorGeometryList	tessellate(DrawContext dc) Tessellate this globe for the currently visible region.

Methods inherited from interface gov.nasa.worldwind.avlist.AVList

addPropertyChangeListener, addPropertyChangeListener, clearList, copy, firePropertyChange, firePropertyChange, getEntries, getStringValue, getValue, getValues, hasKey, removeKey, removePropertyChangeListener, removePropertyChangeListener, setValue, setValues

Methods inherited from interface java.beans.PropertyChangeListener

propertyChange

Methods inherited from interface gov.nasa.worldwind.event.MessageListener

onMessage

Methods inherited from interface gov.nasa.worldwind.geom.Extent

getCenter, getDiameter, getEffectiveRadius, getProjectedArea, getRadius, intersect, intersects, intersects, intersects

Method Detail

computeModelCoordinateOriginTransform

Matrix computeModelCoordinateOriginTransform(Angle latitude,
                                             Angle longitude,
                                             double metersElevation)

See Also:

computeSurfaceOrientationAtPosition(gov.nasa.worldwind.geom.Angle, gov.nasa.worldwind.geom.Angle, double).

computeModelCoordinateOriginTransform

Matrix computeModelCoordinateOriginTransform(Position position)

See Also:

computeSurfaceOrientationAtPosition(gov.nasa.worldwind.geom.Position)

computeNorthPointingTangentAtLocation

Vec4 computeNorthPointingTangentAtLocation(Angle latitude,
                                           Angle longitude)

Computes a vector tangent to this globe and pointing toward the north pole.

Parameters:

latitude - Latitude of the location at which to compute the tangent vector.

longitude - Longitude of the location at which to compute the tangent vector.

Returns:

A vector tangent to this globe at (latitude, longitude), and pointing toward the north pole of this globe.

computePointFromLocation

Vec4 computePointFromLocation(LatLon location)

Computes a cartesian point from a geographic location on the surface of this globe.

Parameters:

location - Geographic location on the surface of the globe to convert to cartesian.

Returns:

The cartesian point that corresponds to the specified geographic location.

computePointFromPosition

Vec4 computePointFromPosition(Angle latitude,
                              Angle longitude,
                              double metersElevation)

Computes a cartesian point from a latitude, longitude, and elevation.

Parameters:

latitude - Latitude of the location to convert to cartesian.

longitude - Longitude of the location to convert to cartesian.

metersElevation - Elevation, in meters, of the geographic position to convert to cartesian.

Returns:

The cartesian point that corresponds to the specified geographic position.

computePointFromPosition

Vec4 computePointFromPosition(LatLon latLon,
                              double metersElevation)

Computes a cartesian point from a geographic location and elevation.

Parameters:

latLon - Geographic location to convert to cartesian.

metersElevation - Elevation, in meters, of the geographic position to convert to cartesian.

Returns:

The cartesian point that corresponds to the specified geographic position.

computePointFromPosition

Vec4 computePointFromPosition(Position position)

Computes a cartesian point from a geographic position.

Parameters:

position - Geographic position to convert to cartesian. The position may include elevation above or below the globe's surface.

Returns:

The cartesian point that corresponds to the specified geographic position.

computePositionFromPoint

Position computePositionFromPoint(Vec4 point)

Computes the geographic position of a point in cartesian coordinates.

Parameters:

point - Point of which to find the geographic position.

Returns:

The geographic position of the specified point.

computeSurfaceNormalAtLocation

Vec4 computeSurfaceNormalAtLocation(Angle latitude,
                                    Angle longitude)

Computes a vector perpendicular to the surface of this globe.

Parameters:

latitude - Latitude of the location at which to compute the normal vector.

longitude - Longitude of the location at which to compute the normal vector.

Returns:

A vector perpendicular to the surface of this globe, at the specified location.

computeSurfaceNormalAtPoint

Vec4 computeSurfaceNormalAtPoint(Vec4 point)

Computes a vector perpendicular to the surface of this globe, at a cartesian point.

Parameters:

point - Point in cartesian coordinates at which to compute the normal vector.

Returns:

A vector perpendicular to the surface of this globe, at the specified point.

computeSurfaceOrientationAtPosition

Matrix computeSurfaceOrientationAtPosition(Angle latitude,
                                           Angle longitude,
                                           double metersElevation)

Returns the cartesian transform Matrix that maps model coordinates to a local coordinate system at (latitude, longitude, metersElevation). The X axis is mapped to the vector tangent to the globe and pointing East. The Y axis is mapped to the vector tangent to the Globe and pointing to the North Pole. The Z axis is mapped to the Globe normal at (latitude, longitude, metersElevation). The origin is mapped to the cartesian position of (latitude, longitude, metersElevation).

Parameters:

latitude - the latitude of the position.

longitude - the longitude of the position.

metersElevation - the number of meters above or below mean sea level.

Returns:

the cartesian transform Matrix that maps model coordinates to the local coordinate system at the specified position.

computeSurfaceOrientationAtPosition

Matrix computeSurfaceOrientationAtPosition(Position position)

Returns the cartesian transform Matrix that maps model coordinates to a local coordinate system at (latitude, longitude, metersElevation). They X axis is mapped to the vector tangent to the globe and pointing East. The Y axis is mapped to the vector tangent to the Globe and pointing to the North Pole. The Z axis is mapped to the Globe normal at (latitude, longitude, metersElevation). The origin is mapped to the cartesian position of (latitude, longitude, metersElevation).

Parameters:

position - the latitude, longitude, and number of meters above or below mean sea level.

Returns:

the cartesian transform Matrix that maps model coordinates to the local coordinate system at the specified position.

getEccentricitySquared

double getEccentricitySquared()

Indicates the square of this globe's eccentricity. Eccentricity is a measure of how the equatorial and polar radii are related.

Returns:

The square of this globe's eccentricity.

getElevation

double getElevation(Angle latitude,
                    Angle longitude)

Indicates the elevation at a specified location. If the elevation at the specified location is the elevation model's missing data signal, or if the location specified is outside the elevation model's coverage area, the elevation model's missing data replacement value is returned.

The elevation returned from this method is the best available in memory. If no elevation is in memory, the elevation model's minimum extreme elevation at the location is returned. Local disk caches are not consulted.

Parameters:

latitude - the latitude of the location at which to determine elevation.

longitude - the longitude of the location at which to determine elevation.

Returns:

The elevation corresponding to the specified location, or the elevation model's missing-data replacement value if there is no elevation for the given location. Returns zero if no elevation model is available.

See Also:

getElevationModel()

getElevationModel

ElevationModel getElevationModel()

Indicates this globe's elevation model.

Returns:

this globe's elevation model.

getElevations

double getElevations(Sector sector,
                     List<? extends LatLon> latlons,
                     double targetResolution,
                     double[] elevations)

Indicates the elevations of a collection of locations. Replaces any elevation values corresponding to the missing data signal with the elevation model's missing data replacement value. If a location within the elevation model's coverage area cannot currently be determined, the elevation model's minimum extreme elevation for that location is returned in the output buffer. If a location is outside the elevation model's coverage area, the output buffer for that location is not modified; it retains the buffer's original value.

Parameters:

sector - the sector in question.

latlons - the locations to return elevations for. If a location is null, the output buffer for that location is not modified.

targetResolution - the desired horizontal resolution, in radians, of the raster or other elevation sample from which elevations are drawn. (To compute radians from a distance, divide the distance by the radius of the globe, ensuring that both the distance and the radius are in the same units.)

elevations - an array in which to place the returned elevations. The array must be pre-allocated and contain at least as many elements as the list of locations.

Returns:

the resolution achieved, in radians, or Double.MAX_VALUE if individual elevations cannot be determined for all of the locations. Returns zero if an elevation model is not available.

See Also:

getElevationModel()

getEquatorialRadius

double getEquatorialRadius()

Indicates the radius of the globe at the equator, in meters.

Returns:

The radius at the equator, in meters.

getExtent

Extent getExtent()

Indicates the spatial volume contained by this globe.

Returns:

An Extent object representing the volume of space enclosed by this globe.

getGlobeStateKey

GlobeStateKey getGlobeStateKey()

Returns a typed state key identifying this globe's current configuration. Can be used to subsequently determine whether the globe's configuration has changed.

Returns:

a state key for the globe's current configuration.

Throws:

IllegalArgumentException - if the draw context is null.

getGlobeStateKey

GlobeStateKey getGlobeStateKey(DrawContext dc)

Returns a typed state key identifying this globe's current configuration. Can be used to subsequently determine whether the globe's configuration has changed.

Parameters:

dc - the current draw context.

Returns:

a state key for the globe's current configuration.

Throws:

IllegalArgumentException - if the draw context is null.

getIntersectionPosition

Position getIntersectionPosition(Line line)

Computes the intersections of this globe and a line.

Parameters:

line - the line with which to intersect this globe.

Returns:

the geographic position of the intersection of this globe and specified line. If there are multiple intersections the intersection nearest to the line's origin is returned. The intersection may be a tangent. Returns null if the line does not intersect this globe.

getMaxElevation

double getMaxElevation()

Indicates the maximum elevation on this globe, in meters.

Returns:

The maximum elevation, or zero if the maximum elevation cannot be determined.

getMaximumRadius

double getMaximumRadius()

Indicates the maximum radius on the globe.

Returns:

The maximum radius, in meters.

getMinAndMaxElevations

double[] getMinAndMaxElevations(Angle latitude,
                                Angle longitude)

Returns the minimum and maximum elevations at a specified location on this Globe. This returns a two-element array filled with zero if this Globe has no elevation model.

Parameters:

latitude - the latitude of the location in question.

longitude - the longitude of the location in question.

Returns:

A two-element double array indicating the minimum and maximum elevations at the specified location, respectively. These values are the global minimum and maximum if the local minimum and maximum values are currently unknown, or zero if this Globe has no elevation model.

getMinAndMaxElevations

double[] getMinAndMaxElevations(Sector sector)

Returns the minimum and maximum elevations within a specified sector on this Globe. This returns a two-element array filled with zero if this Globe has no elevation model.

Parameters:

sector - the sector in question.

Returns:

A two-element double array indicating the sector's minimum and maximum elevations, respectively. These elements are the global minimum and maximum if the local minimum and maximum values are currently unknown, or zero if this Globe has no elevation model.

getMinElevation

double getMinElevation()

Indicates the minimum elevation on this globe, in meters.

Returns:

The minimum elevation, or zero if the minimum elevation cannot be determined.

getPolarRadius

double getPolarRadius()

Indicates the radius of the globe at the poles, in meters.

Returns:

The radius at the poles, in meters.

getRadiusAt

double getRadiusAt(Angle latitude,
                   Angle longitude)

Indicates the radius of the globe at a location.

Parameters:

latitude - Latitude of the location at which to determine radius.

longitude - Longitude of the location at which to determine radius.

Returns:

The radius of the globe at the specified location, in meters.

getRadiusAt

double getRadiusAt(LatLon latLon)

Indicates this globe's radius at a specified location.

Parameters:

latLon - the location of interest.

Returns:

the globe's radius at that location.

getStateKey

Object getStateKey(DrawContext dc)

Returns a state key identifying this globe's current configuration. Can be used to subsequently determine whether the globe's configuration has changed.

Parameters:

dc - the current draw context.

Returns:

a state key for the globe's current configuration.

Throws:

IllegalArgumentException - if the draw context is null.

getTessellator

Tessellator getTessellator()

Returns this globe's current tessellator.

Returns:

the globe's current tessellator.

intersect

Intersection[] intersect(Line line,
                         double altitude)

Intersects a specified line with this globe. Only the ellipsoid itself is considered; terrain elevations are not incorporated.

Parameters:

line - the line to intersect.

altitude - a distance in meters to expand the globe's equatorial and polar radii prior to performing the intersection.

Returns:

the intersection points, or null if no intersection occurs or the line is null.

intersect

Intersection[] intersect(Triangle triangle,
                         double altitude)

Intersects a specified triangle with the globe. Only the ellipsoid itself is considered; terrain elevations are not incorporated.

Parameters:

triangle - the triangle to intersect.

altitude - a distance in meters to expand the globe's equatorial and polar radii prior to performing the intersection.

Returns:

the intersection points, or null if no intersection occurs or triangle is null.

isPointAboveElevation

boolean isPointAboveElevation(Vec4 point,
                              double elevation)

Determines whether a point is above a given elevation.

Parameters:

point - the Vec4 point to test. If null, this method returns false.

elevation - the elevation to test for.

Returns:

true if the given point is above the given elevation, otherwise false.

setElevationModel

void setElevationModel(ElevationModel elevationModel)

Specifies this globe's elevation model.

Parameters:

elevationModel - this globe's elevation model. May be null to indicate no elevation model.

setTessellator

void setTessellator(Tessellator tessellator)

Specifies this globe's tessellator.

Parameters:

tessellator - the new tessellator. Specify null to use the default tessellator.

tessellate

SectorGeometryList tessellate(DrawContext dc)

Tessellate this globe for the currently visible region.

Parameters:

dc - the current draw context.

Returns:

the tessellation, or null if the tessellation failed or the draw context identifies no visible region.

Throws:

IllegalStateException - if the globe has no tessellator and a default tessellator cannot be created.