China
Africa
Explore chapters and articles related to this topic
Geometry and geospatial data on the web
Published in Pieter Pauwels, Kris McGlinn, Buildings and Semantics, 2023
Anna Wagner, Mathias Bonduel, Jeroen Werbrouck, Kris McGlinn
GeoJSON is an encoding based on the JavaScript Object Notation (JSON), developed to support web developers, with the intention of providing a (relatively) simple method to define a geospatial geometry. The basis of an object and the data is given by key-value pairs, and other objects can also form the value for a key, thus enabling nested structures. GeoJSON focuses on a restricted set of features, similar to the OGC simple 2D features, e.g. Point, LineString and Polygon. It also only supports one CRS, WGS 84. GeoJSON does not set out to represent semantics though, and if these are required, it is possible through the use of JSON-LD17.
An open-source web service for creating quadrilateral grids based on the rHEALPix Discrete Global Grid System
Published in International Journal of Digital Earth, 2020
David Bowater, Emmanuel Stefanakis
Although the rHEALPix DGGS can be defined upon any reference ellipsoid (such as GRS80 or WGS84), this web service works strictly with WGS84 geodetic (longitude, latitude) coordinates. Output files from the grid generation operation are encoded in GeoJSON format (the 2016 GeoJSON Specification (RFC 7946) can be found at http://geojson.org/). We chose GeoJSON because it is a simple, text-based format that supports several geometric objects (such as Point, Linestring, and Polygon). In addition, GeoJSON files can easily be converted to other common file formats such as ESRI Shapefile, using free and open-source GIS software (e.g. QGIS). Using this format, we represent a grid as a ‘FeatureCollection’ where each grid cell is encoded as a ‘Feature’ that comprises its unique identifier and geometry. Figure 3 shows an example GeoJSON output file consisting of nine grid cells.
A comprehensive optimization strategy for real-time spatial feature sharing and visual analytics in cyberinfrastructure
Published in International Journal of Digital Earth, 2019
For data exchange and interoperability across different platforms, some commonly used vector layer output formats are supported by WFS, including GML (Geography Markup Language; Cox et al. 2002), KML (Keyhole Markup Language), GeoJSON (Butler et al. 2008), CSV (Comma-Separated Values), etc. Among these formats, GML and GeoJSON are the most commonly used. GeoJSON is designed based on the JSON (JavaScript Objective Notation) format. In GeoJSON, each feature is encoded into an object which consists of a list of key-value pairs that correspond to the name and value of feature attributes. GML is defined by the OGC to express geographic features. Inside of the GML document, the features are organized as a list of XML (eXtensible Markup Language) nodes, where the geometry and attribute information are stored in different tags.
The digital ‘connected’ earth: open technology for providing location-based services on degraded communication environments
Published in International Journal of Digital Earth, 2018
Ramón Piedrafita, Rubén Béjar, Rubén Blasco, Alvaro Marco, F. Javier Zarazaga-Soria
Another possible alternative is the use of GeoJSON (Butler et al. 2016). GeoJSON is a format for encoding a variety of geographic data structures. A GeoJSON object may represent a geometry, a feature or a collection of features. Features in GeoJSON contain a geometry object and additional properties, and a feature collection represents a list of features.