isValidBBox

Signature

isValidBBox (value)

Description

Returns true if value is a valid GeoJSON bounding box: an array of 4 (2D) or 6 (3D) numbers where the south-west and north-east corners are valid positions and south is less than or equal to north. A bbox crossing the antimeridian (west > east) is considered valid.

Parameters

Name	Type	Required	Description
value	*	yes	The value to check

Returns

Type	Description
boolean	true if the value is a valid GeoJSON bounding box

Examples

isValidBBox([-10, -20, 10, 20])              // true
isValidBBox([-10, -20, -100, 10, 20, 100])   // true — 3D
isValidBBox([10, -20, -10, 20])              // true — crosses antimeridian
isValidBBox([-181, -20, 10, 20])             // false — longitude out of range
isValidBBox([-10, 20, 10, -20])              // false — south > north
isValidBBox([-10, -20, 100, 10, 20, -100])   // false — minAlt > maxAlt
isValidBBox(null)                            // false

is3DBBox

Signature

is3DBBox (bbox)

Description

Returns true if bbox is a valid GeoJSON bounding box with altitude coordinates (6 elements).

Parameters

Name	Type	Required	Description
bbox	number[]	yes	A valid GeoJSON bounding box

Returns

Type	Description
boolean	true if the bounding box has 6 coordinates

Throws

Throws if bbox is not a valid GeoJSON bounding box.

Examples

is3DBBox([-10, -20, -100, 10, 20, 100])  // true
is3DBBox([-10, -20, 10, 20])             // false
is3DBBox(null)                           // throws

mergeBBox

Signature

mergeBBox (bbox1, bbox2)

Description

Returns the smallest bounding box that encloses both input bounding boxes. Both inputs must be valid GeoJSON bounding boxes of the same dimensionality (2D or 3D).

Parameters

Name	Type	Required	Description
bbox1	number[]	yes	A valid GeoJSON bounding box
bbox2	number[]	yes	A valid GeoJSON bounding box

Returns

Type	Description
number[]	The merged bounding box

Throws

Throws if either input is not a valid GeoJSON bounding box.

Examples

mergeBBox([-10, -20, 10, 20], [-5, -15, 15, 25])
// [-10, -20, 15, 25]

mergeBBox([-10, -20, -100, 10, 20, 100], [-5, -15, -50, 15, 25, 200])
// [-10, -20, -100, 15, 25, 200]

mergeBBox([-180, -90, 0, 0], [0, 0, 180, 90])
// [-180, -90, 180, 90]

mergeBBox([2.3522, 48.8566, 2.3522, 48.8566], [2.3600, 48.8600, 2.3600, 48.8600])
// [2.3522, 48.8566, 2.3600, 48.8600]

computeBBox

Signature

computeBBox (positions, options)

Description

Computes the bounding box of an array of positions. If any position has an altitude coordinate, the result is a 3D bbox [minX, minY, minZ, maxX, maxY, maxZ]. Otherwise a 2D bbox [minX, minY, maxX, maxY] is returned. This behavior can be overridden with ignore3D.

Parameters

Name	Type	Required	Description
positions	number[][]	yes	A non-empty array of valid GeoJSON positions
options	object	no	Options
options.ignore3D	boolean	no	If true, altitude is ignored and a 2D bbox is always returned (default: false)

Returns

Type	Description
number[]	A 2D [minX, minY, maxX, maxY] or 3D [minX, minY, minZ, maxX, maxY, maxZ] bounding box

Throws

Throws if positions is empty, contains invalid positions, or if options is invalid.

Examples

computeBBox([[2.3522, 48.8566]])
// [2.3522, 48.8566, 2.3522, 48.8566]

computeBBox([[-10, -20], [10, 20], [0, 0]])
// [-10, -20, 10, 20]

computeBBox([[-10, -20, -100], [10, 20, 100]])
// [-10, -20, -100, 10, 20, 100]

computeBBox([[-10, -20, -100], [10, 20, 100]], { ignore3D: true })
// [-10, -20, 10, 20]

truncateBBox

Signature

truncateBBox (bbox, precision)

Description

Truncates each coordinate of a bounding box to the given number of decimal places. Supports both 2D [west, south, east, north] and 3D [west, south, minAlt, east, north, maxAlt] bounding boxes. The operation is performed in place — the original array is mutated and returned.

Parameters

Name	Type	Required	Description
bbox	number[]	yes	A valid bounding box array
precision	number	no	Number of decimal places to keep, in range [0, 8] (default: 7)

Returns

Type	Description
number[]	The mutated bounding box

Throws

Throws if bbox is not a valid bounding box. Throws if precision is not in range [0, 8].

Examples

// Default precision (7)
truncateBBox([-10.123456789, -20.987654321, 10.123456789, 20.987654321])
// [-10.1234568, -20.9876543, 10.1234568, 20.9876543]

// Custom precision
truncateBBox([-10.123456789, -20.987654321, 10.123456789, 20.987654321], 3)
// [-10.123, -20.988, 10.123, 20.988]

// 3D bbox
truncateBBox([-10.123456789, -20.987654321, -100.123456789, 10.123456789, 20.987654321, 100.123456789])
// [-10.1234568, -20.9876543, -100.1234568, 10.1234568, 20.9876543, 100.1234568]

// Mutates in place
const bbox = [-10.123456789, -20.987654321, 10.123456789, 20.987654321]
const result = truncateBBox(bbox, 3)
result === bbox // true