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Map Annotation Schema

Map Annotation Schema (object name: map)

Describes an icon to be placed on a map representing a fixed location resource.  

This tables shows map annotation schemas for the IoT Data Foundations project


This schema utilizes the following naming conventions for the beginning character(s) of the Short Index name:

  • 'l'    fields related to a GPS location – uses Global elements from the GPS object  

Within the schema, certain indexes may require additional clarification. The following list gives additional information for these elements:

  • Timestamp: used for cache control of the map annotation object
  • TimestampCreated: indicates when the symbol was created 
  • Deleted: True if the symbol should be removed from the map; False otherwise  
  • TTL: represents the standard concept of “Time to Live”; indicates how long the map should be annotated.  [Note:  both the “Deleted” and “TTL” indices can be utilized to control the removal of an icon].
  • Url: a web URL linking to additional information pertaining to the icon
  • TextInfo: a string describing the map annotation icon
  • TextHover: a web concept that provides text information when a mouse is hovering over an icon. If there is no value in the TextHover field, then the value within the TextInfo field is used as hover text.
  • TextValid: a string used to provide information that controls the visibility of the icon. The schema should define a format for this string, using concepts such as:
    • days of the week
    • start visibility time
    • end visibility time
    • some manner of specifying periodic patterns of days (e.g., shift schedule)

These values will allow the field to control when icons appear and prevent the first responder’s view from becoming overrun with information.

  • Type of Icon:  a string designator for common icon types across first responder departments. See “Additional Perspective” box for more details.
  •  ZoomVisible, ZoomIndex:  concepts taken from several different map tile (raster scan)-based systems. Both are valuable in controlling visibility at various levels of magnification, such as when several map icons are on top of each other at a specific zoom level but spaced appropriately when the zoom index is increased (the map is zoomed in further).

Additional Perspective

There will eventually need to be agreement on a basic list of icon types to be used within the schema, denoting items such as:

  • stations
  • schools 
  • hospitals
  • staging areas

and other entities that are common across departments. Achieving consensus amongst different groups will be difficult, but if there is agreement on both a list of icons and the symbology used for the icons, the TypeOfIcon index could have a predetermined set of graphic images stored locally on the IoT device, and it would minimize the need for external connectivity to display information. 

Additionally, if the filename of a graphic icon (e.g., "hospitalInService.png") could be agreed upon, then in cases of no network connectivity, the server could easily access the file locally. This means that there would be agreement on the name of the symbol, but the image itself would not necessarily have to be standard.  

Below is a sample list of basic icon types that could be used to initially populate the schema:
            ‘f’    Fire
            ‘e’    EMS
            ‘l’    Law Enforcement
            ‘r’    rescue
            ‘h’    Hazmat
            ‘s’    shelter (civilian)
            ‘e’    Energy (fuel locations)
            ‘l’    Logistics (e.g., staging, base camp, food, sleeping area)
            ‘a’    Aircraft landing zone (e.g., airport, heliport, or drone landing area) 
            ‘z’    Hazards
            ‘A’    Always show this icon
            ‘O’    Other (this category acts as an open label for unspecified symbols)

Created April 7, 2021, Updated April 15, 2021