Ellipsoid - Cesium Documentation

new Ellipsoid(x, y, z)

A quadratic surface defined in Cartesian coordinates by the equation (x / a)^2 + (y / b)^2 + (z / c)^2 = 1. Primarily used by Cesium to represent the shape of planetary bodies. Rather than constructing this object directly, one of the provided constants is normally used.

Name	Type	Default	Description
`x`	Number	`0`	optional The radius in the x direction.
`y`	Number	`0`	optional The radius in the y direction.
`z`	Number	`0`	optional The radius in the z direction.

Throws:

DeveloperError : All radii components must be greater than or equal to zero.

See:

Source: Core/Ellipsoid.js, line 43

Members

staticEllipsoid.MOON

An Ellipsoid instance initialized to a sphere with the lunar radius.

Source: Core/Ellipsoid.js, line 220

staticEllipsoid.UNIT_SPHERE

An Ellipsoid instance initialized to radii of (1.0, 1.0, 1.0).

Source: Core/Ellipsoid.js, line 214

staticEllipsoid.WGS84

An Ellipsoid instance initialized to the WGS84 standard.

See:

czm_getWgs84EllipsoidEC

Source: Core/Ellipsoid.js, line 208

geocentricSurfaceNormal

Computes the unit vector directed from the center of this ellipsoid toward the provided Cartesian position.

Source: Core/Ellipsoid.js, line 243

maximumRadius :Number

Gets the maximum radius of the ellipsoid.

Source: Core/Ellipsoid.js, line 145

minimumRadius :Number

Gets the minimum radius of the ellipsoid.

Source: Core/Ellipsoid.js, line 135

oneOverRadii :Cartesian3

Gets one over the radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 115

oneOverRadiiSquared :Cartesian3

Gets one over the squared radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 125

radii :Cartesian3

Gets the radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 85

radiiSquared :Cartesian3

Gets the squared radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 95

radiiToTheFourth :Cartesian3

Gets the radii of the ellipsoid raise to the fourth power.

Source: Core/Ellipsoid.js, line 105

Methods

staticEllipsoid.clone(ellipsoid, result) → Ellipsoid

Duplicates an Ellipsoid instance.

Name	Type	Description
`ellipsoid`	Ellipsoid	The ellipsoid to duplicate.
`result`	Ellipsoid	optional The object onto which to store the result, or undefined if a new instance should be created.

Returns:

The cloned Ellipsoid. (Returns undefined if ellipsoid is undefined)

Source: Core/Ellipsoid.js, line 162

staticEllipsoid.fromCartesian3(radii) → Ellipsoid

Computes an Ellipsoid from a Cartesian specifying the radii in x, y, and z directions.

Name	Type	Default	Description
`radii`	Cartesian3	`Cartesian3.ZERO`	optional The ellipsoid's radius in the x, y, and z directions.

Returns:

A new Ellipsoid instance.

Throws:

DeveloperError : All radii components must be greater than or equal to zero.

See:

Source: Core/Ellipsoid.js, line 195

cartesianArrayToCartographicArray(cartesians, result) → Cartographic[]

Converts the provided array of cartesians to an array of cartographics.

Name	Type	Description
`cartesians`	Cartesian3[]	An array of Cartesian positions.
`result`	Cartographic[]	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Array instance if none was provided.

Example:

//Create an array of Cartesians and determine their Cartographic representation on a WGS84 ellipsoid.
var positions = [new Cesium.Cartesian3(17832.12, 83234.52, 952313.73),
                 new Cesium.Cartesian3(17832.13, 83234.53, 952313.73),
                 new Cesium.Cartesian3(17832.14, 83234.54, 952313.73)]
var cartographicPositions = Cesium.Ellipsoid.WGS84.cartesianArrayToCartographicArray(positions);

Source: Core/Ellipsoid.js, line 409

cartesianToCartographic(cartesian, result) → Cartographic

Converts the provided cartesian to cartographic representation. The cartesian is undefined at the center of the ellipsoid.

Name	Type	Description
`cartesian`	Cartesian3	The Cartesian position to convert to cartographic representation.
`result`	Cartographic	optional The object onto which to store the result.

Returns:

The modified result parameter, new Cartographic instance if none was provided, or undefined if the cartesian is at the center of the ellipsoid.

Example:

//Create a Cartesian and determine it's Cartographic representation on a WGS84 ellipsoid.
var position = new Cesium.Cartesian(17832.12, 83234.52, 952313.73);
var cartographicPosition = Cesium.Ellipsoid.WGS84.cartesianToCartographic(position);

Source: Core/Ellipsoid.js, line 370

cartographicArrayToCartesianArray(cartographics, result) → Cartesian3[]

Converts the provided array of cartographics to an array of Cartesians.

Name	Type	Description
`cartographics`	Cartographic[]	An array of cartographic positions.
`result`	Cartesian3[]	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Array instance if none was provided.

Example:

//Convert an array of Cartographics and determine their Cartesian representation on a WGS84 ellipsoid.
var positions = [new Cesium.Cartographic(Cesium.Math.toRadians(21), Cesium.Math.toRadians(78), 0),
                 new Cesium.Cartographic(Cesium.Math.toRadians(21.321), Cesium.Math.toRadians(78.123), 100),
                 new Cesium.Cartographic(Cesium.Math.toRadians(21.645), Cesium.Math.toRadians(78.456), 250)
var cartesianPositions = Cesium.Ellipsoid.WGS84.cartographicArrayToCartesianArray(positions);

Source: Core/Ellipsoid.js, line 333

cartographicToCartesian(cartographic, result) → Cartesian3

Converts the provided cartographic to Cartesian representation.

Name	Type	Description
`cartographic`	Cartographic	The cartographic position.
`result`	Cartesian3	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Cartesian3 instance if none was provided.

Example:

//Create a Cartographic and determine it's Cartesian representation on a WGS84 ellipsoid.
var position = new Cesium.Cartographic(Cesium.Math.toRadians(21), Cesium.Math.toRadians(78), 5000);
var cartesianPosition = Cesium.Ellipsoid.WGS84.cartographicToCartesian(position);

Source: Core/Ellipsoid.js, line 306

clone(result) → Ellipsoid

Duplicates an Ellipsoid instance.

Name	Type	Description
`result`	Ellipsoid	optional The object onto which to store the result, or undefined if a new instance should be created.

Returns:

The cloned Ellipsoid.

Source: Core/Ellipsoid.js, line 231

equals(right) → Boolean

Compares this Ellipsoid against the provided Ellipsoid componentwise and returns true if they are equal, false otherwise.

Name	Type	Description
`right`	Ellipsoid	optional The other Ellipsoid.

Returns:

true if they are equal, false otherwise.

Source: Core/Ellipsoid.js, line 604

geodeticSurfaceNormal(cartesian, result) → Cartesian3

Computes the normal of the plane tangent to the surface of the ellipsoid at the provided position.

Name	Type	Description
`cartesian`	Cartesian3	The Cartesian position for which to to determine the surface normal.
`result`	Cartesian3	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Cartesian3 instance if none was provided.

Source: Core/Ellipsoid.js, line 285

geodeticSurfaceNormalCartographic(cartographic, result) → Cartesian3

Computes the normal of the plane tangent to the surface of the ellipsoid at the provided position.

Name	Type	Description
`cartographic`	Cartographic	The cartographic position for which to to determine the geodetic normal.
`result`	Cartesian3	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Cartesian3 instance if none was provided.

Source: Core/Ellipsoid.js, line 253

scaleToGeocentricSurface(cartesian, result) → Cartesian3

Scales the provided Cartesian position along the geocentric surface normal so that it is on the surface of this ellipsoid.

Name	Type	Description
`cartesian`	Cartesian3	The Cartesian position to scale.
`result`	Cartesian3	optional The object onto which to store the result.

Returns:

The modified result parameter or a new Cartesian3 instance if none was provided.

Source: Core/Ellipsoid.js, line 545

scaleToGeodeticSurface(cartesian, result) → Cartesian3

Scales the provided Cartesian position along the geodetic surface normal so that it is on the surface of this ellipsoid. If the position is at the center of the ellipsoid, this function returns undefined.

Name	Type	Description
`cartesian`	Cartesian3	The Cartesian position to scale.
`result`	Cartesian3	optional The object onto which to store the result.

Returns:

The modified result parameter, a new Cartesian3 instance if none was provided, or undefined if the position is at the center.

Source: Core/Ellipsoid.js, line 441

toString() → String

Creates a string representing this Ellipsoid in the format '(radii.x, radii.y, radii.z)'.

Returns:

A string representing this ellipsoid in the format '(radii.x, radii.y, radii.z)'.

Source: Core/Ellipsoid.js, line 616

transformPositionFromScaledSpace(position, result) → Cartesian3

Transforms a Cartesian X, Y, Z position from the ellipsoid-scaled space by multiplying its components by the result of Ellipsoid#radii.

Name	Type	Description
`position`	Cartesian3	The position to transform.
`result`	Cartesian3	optional The position to which to copy the result, or undefined to create and return a new instance.

Returns:

The position expressed in the unscaled space. The returned instance is the one passed as the result parameter if it is not undefined, or a new instance of it is.

Source: Core/Ellipsoid.js, line 592

transformPositionToScaledSpace(position, result) → Cartesian3

Transforms a Cartesian X, Y, Z position to the ellipsoid-scaled space by multiplying its components by the result of Ellipsoid#oneOverRadii.

Name	Type	Description
`position`	Cartesian3	The position to transform.
`result`	Cartesian3	optional The position to which to copy the result, or undefined to create and return a new instance.

Returns:

The position expressed in the scaled space. The returned instance is the one passed as the result parameter if it is not undefined, or a new instance of it is.

Source: Core/Ellipsoid.js, line 576