Definition of "extent"

NOTE: Markdown does not support highlighting in color, so bold/italic has been used to highlight the material being discussed. This issue is extracted from the document submitted by Roger Lott at https://github.com/opengeospatial/CRS-JSON-Encoding/blob/main/ProjJson%20v0-7%20RL%202024-06-16.docx for discussion at the CRS SWG meeting OGC held during the Montreal June 2024 TC meeting.

"extent": {
    "type": "array",
    "items": {
      "type": "object",
      "properties": {

"extent_description": { "type": "string" },

        "bbox": { "$ref": "#/definitions/bbox" },
        "extent_polygon": { "type": "array" },
        "vertical_extent": { "$ref": "#/definitions/vertical_extent" },
        "temporal_extent": { "$ref": "#/definitions/temporal_extent" }
       },

"required" : [ "extent_description", "bbox" ],

      "additionalProperties": false
    }
},

"$comment": "[RL] In ISO 19111 [OGC Abstract Spec Topic 2](from ISO 19115 [OGC Abstract Spec Topic 11]) an extent must contain at least one of the above properties; it may contain any or all of these properties. In ISO 19127 (geodetic registry) this is specialised: a description and a bbox are made mandatory, the remaining properties are optional. If this is considered best practice for geodetic registries, should it be considered as appropriate for CRS JSON?"

Beginnen Sie mit dem Auszug aus dem extent-Schema in diesem Issue und dem verknüpften ProjJson v0-7 RL 2024-06-16.docx und prüfen Sie anschließend die zitierten Anforderungen aus ISO 19111 und ISO 19127. Klären Sie, ob extent_description und bbox in CRS JSON obligatorisch sein sollten, und dokumentieren Sie die vereinbarte Schemaänderung oder Begründung.