BoundingSphere - Cesium Documentation

new BoundingSphere

A bounding sphere with a center and a radius.

Parameters:

Name	Type	Argument	Default	Description
`center`	Cartesian3	<optional>	Cartesian3.ZERO	The center of the bounding sphere.
`radius`	Number	<optional>	0.0	The radius of the bounding sphere.

See:

Source:

ingSphere.js

Members

center :Cartesian3

The center point of the sphere.

Default Value:

Cartesian3.ZERO

radius :Number

The radius of the sphere.

Default Value:

<static> packedLength :Number

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

Methods

clone

Duplicates this BoundingSphere instance.

Parameters:

Name	Type	Argument	Description
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

equals

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

Parameters:

Name	Type	Argument	Description
`right`	BoundingSphere	<optional>	The right hand side BoundingSphere.

Returns:

Boolean true if they are equal, false otherwise.

intersect

Determines which side of a plane the sphere is located.

Parameters:

Name	Type	Description
`plane`	Cartesian4	The coefficients of the plane in the for ax + by + cz + d = 0 where the coefficients a, b, c, and d are the components x, y, z, and w of the {Cartesian4}, respectively.

Returns:

Intersect {Intersect.INSIDE} if the entire sphere is on the side of the plane the normal is pointing, {Intersect.OUTSIDE} if the entire sphere is on the opposite side, and {Intersect.INTERSETING} if the sphere intersects the plane.

<static> clone

Duplicates a BoundingSphere instance.

Parameters:

Name	Type	Argument	Description
`sphere`	BoundingSphere		The bounding sphere to duplicate.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

BoundingSphere The modified result parameter or a new BoundingSphere instance if none was provided. (Returns undefined if sphere is undefined)

<static> distanceSquaredTo

Computes the estimated distance squared from the closest point on a bounding sphere to a point.

Parameters:

Name	Type	Description
`sphere`	BoundingSphere	The sphere.
`cartesian`	Cartesian3	The point

Returns:

Number The estimated distance squared from the bounding sphere to the point.

Example

// Sort bounding spheres from back to front
spheres.sort(function(a, b) {
    return BoundingSphere.distanceSquaredTo(b, camera.positionWC) - BoundingSphere.distanceSquaredTo(a, camera.positionWC);
});

<static> equals

Compares the provided BoundingSphere componentwise and returns true if they are equal, false otherwise.

Parameters:

Name	Type	Argument	Description
`left`	BoundingSphere	<optional>	The first BoundingSphere.
`right`	BoundingSphere	<optional>	The second BoundingSphere.

Returns:

Boolean true if left and right are equal, false otherwise.

<static> expand

Computes a bounding sphere by enlarging the provided sphere to contain the provided point.

Parameters:

Name	Type	Argument	Description
`sphere`	BoundingSphere		A sphere to expand.
`point`	Cartesian3		A point to enclose in a bounding sphere.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

<static> fromCornerPoints

Computes a bounding sphere from the corner points of an axis-aligned bounding box. The sphere tighly and fully encompases the box.

Parameters:

Name	Type	Argument	Description
`corner`	Number	<optional>	The minimum height over the rectangle.
`oppositeCorner`	Number	<optional>	The maximum height over the rectangle.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

Example

// Create a bounding sphere around the unit cube
var sphere = Cesium.BoundingSphere.fromCornerPoints(new Cesium.Cartesian3(-0.5, -0.5, -0.5), new Cesium.Cartesian3(0.5, 0.5, 0.5));

<static> fromEllipsoid

Creates a bounding sphere encompassing an ellipsoid.

Parameters:

Name	Type	Argument	Description
`ellipsoid`	Ellipsoid		The ellipsoid around which to create a bounding sphere.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

Example

var boundingSphere = Cesium.BoundingSphere.fromEllipsoid(ellipsoid);

<static> fromPoints

Computes a tight-fitting bounding sphere enclosing a list of 3D Cartesian points. The bounding sphere is computed by running two algorithms, a naive algorithm and Ritter's algorithm. The smaller of the two spheres is used to ensure a tight fit.

Parameters:

Name	Type	Argument	Description
`positions`	Array		An array of points that the bounding sphere will enclose. Each point must have `x`, `y`, and `z` properties.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

BoundingSphere The modified result parameter or a new BoundingSphere instance if one was not provided.

See:

Bounding Sphere computation article

<static> fromRectangle2D

Computes a bounding sphere from an rectangle projected in 2D.

Parameters:

Name	Type	Argument	Default	Description
`rectangle`	Rectangle			The rectangle around which to create a bounding sphere.
`projection`	Object	<optional>	GeographicProjection	The projection used to project the rectangle into 2D.
`result`	BoundingSphere	<optional>		The object onto which to store the result.

Returns:

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

<static> fromRectangle3D

Computes a bounding sphere from an rectangle in 3D. The bounding sphere is created using a subsample of points on the ellipsoid and contained in the rectangle. It may not be accurate for all rectangles on all types of ellipsoids.

Parameters:

Name	Type	Argument	Default	Description
`rectangle`	Rectangle			The valid rectangle used to create a bounding sphere.
`ellipsoid`	Ellipsoid	<optional>	Ellipsoid.WGS84	The ellipsoid used to determine positions of the rectangle.
`surfaceHeight`	Number	<optional>	0.0	The height above the surface of the ellipsoid.
`result`	BoundingSphere	<optional>		The object onto which to store the result.

Returns:

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

<static> fromRectangleWithHeights2D

Computes a bounding sphere from an rectangle projected in 2D. The bounding sphere accounts for the object's minimum and maximum heights over the rectangle.

Parameters:

Name	Type	Argument	Default	Description
`rectangle`	Rectangle			The rectangle around which to create a bounding sphere.
`projection`	Object	<optional>	GeographicProjection	The projection used to project the rectangle into 2D.
`minimumHeight`	Number	<optional>	0.0	The minimum height over the rectangle.
`maximumHeight`	Number	<optional>	0.0	The maximum height over the rectangle.
`result`	BoundingSphere	<optional>		The object onto which to store the result.

Returns:

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

<static> fromVertices

Computes a tight-fitting bounding sphere enclosing a list of 3D points, where the points are stored in a flat array in X, Y, Z, order. The bounding sphere is computed by running two algorithms, a naive algorithm and Ritter's algorithm. The smaller of the two spheres is used to ensure a tight fit.

Parameters:

Name	Type	Argument	Default	Description
`positions`	Array			An array of points that the bounding sphere will enclose. Each point is formed from three elements in the array in the order X, Y, Z.
`center`	Cartesian3	<optional>	Cartesian3.ZERO	The position to which the positions are relative, which need not be the origin of the coordinate system. This is useful when the positions are to be used for relative-to-center (RTC) rendering.
`stride`	Number	<optional>	3	The number of array elements per vertex. It must be at least 3, but it may be higher. Regardless of the value of this parameter, the X coordinate of the first position is at array index 0, the Y coordinate is at array index 1, and the Z coordinate is at array index 2. When stride is 3, the X coordinate of the next position then begins at array index 3. If the stride is 5, however, two array elements are skipped and the next position begins at array index 5.
`result`	BoundingSphere	<optional>		The object onto which to store the result.

Returns:

BoundingSphere The modified result parameter or a new BoundingSphere instance if one was not provided.

Example

// Compute the bounding sphere from 3 positions, each specified relative to a center.
// In addition to the X, Y, and Z coordinates, the points array contains two additional
// elements per point which are ignored for the purpose of computing the bounding sphere.
var center = new Cesium.Cartesian3(1.0, 2.0, 3.0);
var points = [1.0, 2.0, 3.0, 0.1, 0.2,
              4.0, 5.0, 6.0, 0.1, 0.2,
              7.0, 8.0, 9.0, 0.1, 0.2];
var sphere = Cesium.BoundingSphere.fromVertices(points, center, 5);

See:

Bounding Sphere computation article

<static> getPlaneDistances

The distances calculated by the vector from the center of the bounding sphere to position projected onto direction plus/minus the radius of the bounding sphere.
If you imagine the infinite number of planes with normal direction, this computes the smallest distance to the closest and farthest planes from position that intersect the bounding sphere.

Parameters:

Name	Type	Argument	Description
`sphere`	BoundingSphere		The bounding sphere to calculate the distance to.
`position`	Cartesian3		The position to calculate the distance from.
`direction`	Cartesian3		The direction from position.
`result`	Cartesian2	<optional>	A Cartesian2 to store the nearest and farthest distances.

Returns:

Interval The nearest and farthest distances on the bounding sphere from position in direction.

<static> intersect

Determines which side of a plane a sphere is located.

Parameters:

Name	Type	Description
`sphere`	BoundingSphere	The bounding sphere to test.
`plane`	Cartesian4	The coefficients of the plane in the for ax + by + cz + d = 0 where the coefficients a, b, c, and d are the components x, y, z, and w of the {Cartesian4}, respectively.

Returns:

<static> pack

Stores the provided instance into the provided array.

Parameters:

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

<static> projectTo2D

Creates a bounding sphere in 2D from a bounding sphere in 3D world coordinates.

Parameters:

Name	Type	Argument	Default	Description
`sphere`	BoundingSphere			The bounding sphere to transform to 2D.
`projection`	Object	<optional>	GeographicProjection	The projection to 2D.
`result`	BoundingSphere	<optional>		The object onto which to store the result.

Returns:

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

<static> transform

Applies a 4x4 affine transformation matrix to a bounding sphere.

Parameters:

Name	Type	Argument	Description
`sphere`	BoundingSphere		The bounding sphere to apply the transformation to.
`transform`	Matrix4		The transformation matrix to apply to the bounding sphere.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

<static> transformWithoutScale

Applies a 4x4 affine transformation matrix to a bounding sphere where there is no scale The transformation matrix is not verified to have a uniform scale of 1. This method is faster than computing the general bounding sphere transform using transform.

Parameters:

Name	Type	Argument	Description
`sphere`	BoundingSphere		The bounding sphere to apply the transformation to.
`transform`	Matrix4		The transformation matrix to apply to the bounding sphere.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

Example

var modelMatrix = Cesium.Transforms.eastNorthUpToFixedFrame(positionOnEllipsoid);
var boundingSphere = new Cesium.BoundingSphere();
var newBoundingSphere = Cesium.BoundingSphere.transformWithoutScale(boundingSphere, modelMatrix);

<static> union

Computes a bounding sphere that contains both the left and right bounding spheres.

Parameters:

Name	Type	Argument	Description
`left`	BoundingSphere		A sphere to enclose in a bounding sphere.
`right`	BoundingSphere		A sphere to enclose in a bounding sphere.
`result`	BoundingSphere	<optional>	The object onto which to store the result.

Returns:

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

<static> unpack

Retrieves an instance from a packed array.

Parameters:

Name	Type	Argument	Default	Description
`array`	Array			The packed array.
`startingIndex`	Number	<optional>	0	The starting index of the element to be unpacked.
`result`	Cartesian3	<optional>		The object into which to store the result.