org.cesiumjs.cs.core.projection

Class WebMercatorProjection

java.lang.Object

org.cesiumjs.cs.core.projection.MapProjection

org.cesiumjs.cs.core.projection.WebMercatorProjection

@JsType(isNative=true,
        namespace="Cesium",
        name="WebMercatorProjection")
public class WebMercatorProjection
extends MapProjection

The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857. This projection use longitude and latitude expressed with the WGS84 and transforms them to Mercator using the spherical (rather than ellipsoidal) equations.

Author:

Serge Silaev aka iSergio

Constructor Summary

Constructors

Constructor and Description
WebMercatorProjection() The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857.
WebMercatorProjection(Ellipsoid ellipsoid) The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857.

Method Summary

Modifier and Type	Method and Description
Ellipsoid	ellipsoid() Gets the Ellipsoid.
static double	geodeticLatitudeToMercatorAngle(double latitude) Converts a geodetic latitude in radians, in the range -PI/2 to PI/2, to a Mercator angle in the range -PI to PI.
static double	MaximumLatitude() The maximum latitude (both North and South) supported by a Web Mercator (EPSG:3857) projection.
static double	mercatorAngleToGeodeticLatitude(double mercatorAngle) Converts a Mercator angle, in the range -PI to PI, to a geodetic latitude in the range -PI/2 to PI/2.

Methods inherited from class org.cesiumjs.cs.core.projection.MapProjection

project, project, unproject, unproject

Methods inherited from class java.lang.Object

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

Constructor Detail

WebMercatorProjection

@JsConstructor
public WebMercatorProjection()

The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857. This projection use longitude and latitude expressed with the WGS84 and transforms them to Mercator using the spherical (rather than ellipsoidal) equations.

See Also:

GeographicProjection

WebMercatorProjection

@JsConstructor
public WebMercatorProjection(Ellipsoid ellipsoid)

The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857. This projection use longitude and latitude expressed with the WGS84 and transforms them to Mercator using the spherical (rather than ellipsoidal) equations.

Parameters:

ellipsoid - The ellipsoid.

See Also:

GeographicProjection

Method Detail

MaximumLatitude

@JsProperty(name="MaximumLatitude")
public static double MaximumLatitude()

The maximum latitude (both North and South) supported by a Web Mercator (EPSG:3857) projection. Technically, the Mercator projection is defined for any latitude up to (but not including) 90 degrees, but it makes sense to cut it off sooner because it grows exponentially with increasing latitude. The logic behind this particular cutoff value, which is the one used by Google Maps, Bing Maps, and Esri, is that it makes the projection square. That is, the rectangle is equal in the X and Y directions. The constant value is computed by calling: mercatorAngleToGeodeticLatitude(double)

ellipsoid

@JsProperty(name="ellipsoid")
public Ellipsoid ellipsoid()

Gets the Ellipsoid.

Overrides:

ellipsoid in class MapProjection

geodeticLatitudeToMercatorAngle

@JsMethod
public static double geodeticLatitudeToMercatorAngle(double latitude)

Converts a geodetic latitude in radians, in the range -PI/2 to PI/2, to a Mercator angle in the range -PI to PI.

Parameters:

latitude - The geodetic latitude in radians.

Returns:

The Mercator angle.

mercatorAngleToGeodeticLatitude

@JsMethod
public static double mercatorAngleToGeodeticLatitude(double mercatorAngle)

Converts a Mercator angle, in the range -PI to PI, to a geodetic latitude in the range -PI/2 to PI/2.

Parameters:

mercatorAngle - The angle to convert.

Returns:

The geodetic latitude in radians.