A Map Composition may be used as a portable configuration file that enables a map to be recreated in any client application. However, at present, the working specification is limited to referencing data served from Web Map and Feature Servers as well as KML and GeoJSON documents available at a working URL.
This allows Internet map authors to create and share their Map Compositions, or simply “maps”, based on their professional skills and experience in combining existing data.
We believe that it in addition would be interesting if map authors were able to add their own annotation in the Map Composition and that this could be stored as embedded data within the Map Composition object without relying on 3rd party servers or data uploaded to remote web servers.
The current working version of the Map Composition JSON schema may be found in the wiki section of the HSLayers NG GitHub repository. An issue to be addressed during the INSPIRE Hack may be to extend this schema to permit inclusion of embedded map markup.
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