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.
Members
-
staticconstantCesium.Ellipsoid.MOON : Ellipsoid
-
An Ellipsoid instance initialized to a sphere with the lunar radius.
-
The number of elements used to pack the object into an array.
-
staticconstantCesium.Ellipsoid.UNIT_SPHERE : Ellipsoid
-
An Ellipsoid instance initialized to radii of (1.0, 1.0, 1.0).
-
staticconstantCesium.Ellipsoid.WGS84 : Ellipsoid
-
An Ellipsoid instance initialized to the WGS84 standard.
-
Gets the maximum radius of the ellipsoid.
-
Gets the minimum radius of the ellipsoid.
-
readonlyoneOverRadii : Cartesian3
-
Gets one over the radii of the ellipsoid.
-
readonlyoneOverRadiiSquared : Cartesian3
-
Gets one over the squared radii of the ellipsoid.
-
readonlyradii : Cartesian3
-
Gets the radii of the ellipsoid.
-
readonlyradiiSquared : Cartesian3
-
Gets the squared radii of the ellipsoid.
-
readonlyradiiToTheFourth : Cartesian3
-
Gets the radii of the ellipsoid raise to the fourth power.
Methods
-
staticCesium.Ellipsoid.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) -
staticCesium.Ellipsoid.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.
-
-
Stores the provided instance into the provided array.
Name Type Default Description value
Ellipsoid 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. -
staticCesium.Ellipsoid.unpack(array, startingIndex, result) → Ellipsoid
-
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. Returns:
The modified result parameter or a new Ellipsoid instance if one was not provided. -
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);
-
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.Cartesian3(17832.12, 83234.52, 952313.73); var cartographicPosition = Cesium.Ellipsoid.WGS84.cartesianToCartographic(position);
-
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);
-
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);
-
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. -
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. -
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. -
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. -
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. -
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. -
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. -
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)'. -
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. -
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.