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 78

Members

staticconstantEllipsoid.MOON :Ellipsoid

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

Source: Core/Ellipsoid.js, line 240

staticEllipsoid.packedLength :Number

The number of elements used to pack the object into an array.

Source: Core/Ellipsoid.js, line 257

staticconstantEllipsoid.UNIT_SPHERE :Ellipsoid

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

Source: Core/Ellipsoid.js, line 232

staticconstantEllipsoid.WGS84 :Ellipsoid

An Ellipsoid instance initialized to the WGS84 standard.

Source: Core/Ellipsoid.js, line 224

maximumRadius :Number

Gets the maximum radius of the ellipsoid.

Source: Core/Ellipsoid.js, line 157

minimumRadius :Number

Gets the minimum radius of the ellipsoid.

Source: Core/Ellipsoid.js, line 147

oneOverRadii :Cartesian3

Gets one over the radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 127

oneOverRadiiSquared :Cartesian3

Gets one over the squared radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 137

radii :Cartesian3

Gets the radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 97

radiiSquared :Cartesian3

Gets the squared radii of the ellipsoid.

Source: Core/Ellipsoid.js, line 107

radiiToTheFourth :Cartesian3

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

Source: Core/Ellipsoid.js, line 117

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 172

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 205

staticEllipsoid.pack(value, array, startingIndex)

Stores the provided instance into the provided array.

Name	Type	Default	Description
`value`	Object		The value to pack.
`array`	Array.<Number>		The array to pack into.
`startingIndex`	Number	`0`	optional The index into the array at which to start packing the elements.

Source: Core/Ellipsoid.js, line 267

staticEllipsoid.unpack(array, startingIndex, result)

Retrieves an instance from a packed array.

Name	Type	Default	Description
`array`	Array.<Number>		The packed array.
`startingIndex`	Number	`0`	optional The starting index of the element to be unpacked.
`result`	Ellipsoid		optional The object into which to store the result.

Source: Core/Ellipsoid.js, line 289

cartesianArrayToCartographicArray(cartesians, result) → Array.<Cartographic>

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

Name	Type	Description
`cartesians`	Array.<Cartesian3>	An array of Cartesian positions.
`result`	Array.<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 477

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 439

cartographicArrayToCartesianArray(cartographics, result) → Array.<Cartesian3>

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

Name	Type	Description
`cartographics`	Array.<Cartographic>	An array of cartographic positions.
`result`	Array.<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 403

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 373

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 249

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 677

geocentricSurfaceNormal(cartesian, result) → Cartesian3

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

Name	Type	Description
`cartesian`	Cartesian3	The Cartesian for which to to determine the geocentric 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 310

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 350

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 319

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 611

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 508

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 688

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 662

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 644