boost-geospatial-index

Stores and indexes geospatial shapes and exposes query methods.
Shapes can overlap.

This library is used by Kuzzle's real-time engine and is focused on query performances:

• shapes are indexed using a R* tree ("slow" insertion, very fast query time)
• based on the C++ boost::geometry library
• pure C++ module
• no dependencies

Table of content

• Install
• API
  • Creating a new index
  • Adding shapes to the index
    • addBoundingBox(id, min_lat, min_lon, max_lat, max_lon)
    • addCircle(id, lat, lon, radius)
    • addAnnulus(id, lat, lon, outer, inner)
    • addPolygon(id, points)
• Querying the index
  • queryPoint(lat, lon)
  • queryIntersect(points)
• Removing a shape from the index
  • remove(id)
• Example
• TODO
• License

Install

npm install --save boost-geospatial-index

API

Creating a new index

var BoostSpatialIndex = require('boost-geospatial-index');

var bsi = new BoostSpatialIndex();

Adding shapes to the index

addBoundingBox(id, min_lat, min_lon, max_lat, max_lon)

Returns: boolean

Argument	Type	Description
id	string	shape unique identifier
min_lat	number	bottom side of the bounding box
min_lon	number	left side of the bounding box
max_lat	number	top side of the bounding box
max_lon	number	right side of the bounding box

addCircle(id, lat, lon, radius)

Returns: boolean

Argument	Type	Description
id	string	shape unique identifier
lat	number	y coordinate of the circle's center
lon	number	x coordinate of the circle's center
radius	number	radius of the circle, in meters

addAnnulus(id, lat, lon, outer, inner)

Returns: boolean

Argument	Type	Description
id	string	shape unique identifier
lat	number	y coordinate of the annulus' center
lon	number	x coordinate of the annulus' center
outer	number	outer radius of the annulus, in meters
inner	number	inner radius of the annulus, in meters

addPolygon(id, points)

Creates an open polygon (automatically closed by the library).

Returns: boolean

Argument	Type	Description
id	string	shape unique identifier
points	array	array of arrays of [lat, lon] points

Querying the index

queryPoint(lat, lon)

Gets all shapes containing the provided point coordinates. Shapes matching the provided point exactly on their borders or corners are also returned.

If no shape match, an empty array is returned.

Returns: array of shape ids

Argument	Type	Description
lat	number	y coordinate
lon	number	x coordinate

queryIntersect(points)

Gets all shapes intersecting the polygon created from the list of point coordinates provided. Shapes partially covered by the polygon also returned.

If no shape match, an empty array is returned.

Returns: array of shape ids

Argument	Type	Description
points	array	array of arrays of [lat, lon] points

Removing a shape from the index

remove(id)

Returns: boolean

Argument	Type	Description
id	string	shape unique identifier

Example

var BoostSpatialIndex = require('boost-geospatial-index');

var bsi = new BoostSpatialIndex();

bsi.addBoundingBox('Montpellier, France', 43.5810609, 3.8433703, 43.6331979, 3.9282093);
bsi.addPolygon('Montpellier Millenaire', [
  [43.6021299, 3.8989713],
  [43.6057389, 3.8968173],
  [43.6092889, 3.8970423],
  [43.6100359, 3.9040853],
  [43.6069619, 3.9170343],
  [43.6076479, 3.9230133],
  [43.6038779, 3.9239153],
  [43.6019189, 3.9152403],
  [43.6036049, 3.9092313]
]);
bsi.addAnnulus('Around Kuzzle HQ', 43.6073913, 3.9109057, 1500, 1);
bsi.addCircle('Montpellier Airport', 43.5764455, 3.948711, 2000);

console.log('Querying Kuzzle HQ: ', bsi.queryPoint(43.6073913, 3.9109057));
console.log('Kuzzle team favorite pub:', bsi.queryPoint(43.6002203, 3.897105));
console.log('Hangout spots:', bsi.queryIntersect([
            [43.6072203, 3.9],
            [43.607,5.900],
            [44.609000, 5.90000],
            [44.605,3.9]
            ]));

Result:

Querying Kuzzle HQ:  [ 'Montpellier, France', 'Montpellier Millenaire' ]
Kuzzle team favorite pub: [ 'Montpellier, France', 'Around Kuzzle HQ' ]
Hangout spots: [ 'Montpellier, France',
  'Montpellier Millenaire',
  'Around Kuzzle HQ' ]

TODO

Here are some features we might add in the future:

• add support for polygons with inner holes

Update Boost headers

• rm -rf boost-geospatial-index/include/boost
• Download last boost version : https://www.boost.org/users/download/
• Unzip then follow this steps
• ./bootstrap.sh
• ./b2 tools/bcp
• ./dist/bin/bcp boost/geometry.hpp boost-geospatial-index/include/

License

This library is published under Apache 2 License.