-sgillies@frii.com -http://zcologia.com/sgillies +sgillies@frii.com +http://zcologia.com/sgillies
Contents
GeoJSON is a data-interchange format for a variety of geographic data structures. GeoJSON can be used to represent a geometry, a feature, a collection of geometries, or a collection of features. The geometry types @@ -324,8 +90,8 @@ a string, number, object, array or one o a string, number, object, array or one of the literals: "true", "false", and "null". An array consists of elements where each element is a value as described above.
-A GeoJSON feature collection:
{ "type": "FeatureCollection",
@@ -363,37 +129,36 @@ described above.
}
GeoJSON always consists of a single object. This object (referred to as the -GeoJSON object below) represents a geometry, feature, collection of geometries, -or collection of features.
+GeoJSON object below) represents a geometry, feature, or collection of features.A geometry is a GeoJSON object where the type member's value is one of the following strings: "Point", "MultiPoint", "LineString", "MultiLineString", "Polygon", "MultiPolygon", or "GeometryCollection".
@@ -401,8 +166,8 @@ a member with the name "coordinates a member with the name "coordinates". The value of the coordinates member is always an array. The structure for the elements in this array are determined by the type of geometry. -For type "Point", each element in the coordinates array is a number representing the point coordinate in one dimension. There must be at least two elements, and may be more. The order of elements must follow x, y, z order (or @@ -411,13 +176,13 @@ interpretation and meaning of these coor interpretation and meaning of these coordinates is beyond the scope of this specification.
For type "MultiPoint", each element in the coordinates array is a coordinates array as described for type "Point".
For type "LineString", each element in the coordinates array is a coordinates array as described for type "Point". The coordinates array for a LineString must have two or more elements. A LinearRing is a special case of type @@ -426,26 +191,26 @@ explicitly represented as a GeoJSON geom explicitly represented as a GeoJSON geometry type, it is referred to in the Polygon geometry type definition.
For type "MultiLineString", each element in the coordinates array is a coordinates array as described for type "LineString".
For type "Polygon", each element in the coordinates array is a coordinates array as described for type "LineString". Furthermore, each LineString in the coordinates array must be a LinearRing. For Polygons with multiple LinearRings, the first must be the exterior ring and any others must be interior rings or holes.
For type "MultiPolygon", each element in the coordinates array is a coordinates array as described for type "Polygon".
A GeoJSON object with type "GeometryCollection" is a geometry object which represents a collection of geometry objects.
A geometry collection must have a member with the name "geometries". The value @@ -453,8 +218,8 @@ GeoJSON geometry object.
GeoJSON geometry object.A GeoJSON object with the type "Feature" is a feature object.
A GeoJSON object with the type "FeatureCollection" is a feature collection object.
An object of type "FeatureCollection" must have a member with the name @@ -475,8 +240,8 @@ the array is a feature object as defined the array is a feature object as defined above.
The coordinate reference system (CRS) of a GeoJSON object is determined by its "crs" member (referred to as the CRS object below). If an object has no "crs" member, its parent object's "crs" member may be acquired. If no CRS can be so @@ -492,8 +257,8 @@ object.
A CRS object may indicate a coordinate reference system by name. The value of its "properties" member must be an object containing a "name" member. The value of that "name" member must be a string identifying a coordinate reference @@ -508,12 +273,12 @@ preferred over legacy identifiers such a }
A CRS object may link to CRS parameters on the Web. In this case the value of -its "properties" member must be a Link object (see 3.2.1. Link Objects).
-A link object has 1 required member: "href", and 1 optional member: "type".
The value of the required "href" member must be a dereferenceable URI.
The value of the optional "type" member must be a string that hints at the @@ -542,8 +307,8 @@ auxiliary file:
To include information on the coordinate range for geometries, features, or feature collections, a GeoJSON object may have a member named "bbox". The value of the bbox member should be a 2*n item array where n is the number of @@ -574,11 +339,11 @@ the spatial reference for the GeoJSON ob }
The GeoJSON format specification is the product of discussion on the GeoJSON list:
-http://lists.geojson.org/listinfo.cgi/geojson-geojson.org
+http://lists.geojson.org/listinfo.cgi/geojson-geojson.org
The following people contributed to draft versions of this document: