location is a key aspect of checkin and event posts. It's also sometimes an aspect of posts in general, e.g. where a note or photo/video was posted from. The aspect of location is sometimes referred to as geo for short.
- Wordpress' simple location plugin displays location data for posts
- Instagram displays the location below the title on detail pages and links it to a location page on the platform.
- When you mention "place" in a post, Facebook will prompt you to add a location to the post.
- Aaron Parecki displays location information with posts, e.g. https://aaronparecki.com/2016/09/19/18/
- Peter Molnar displays geo coordinates for photo posts when the photos have coordinates in their EXIF data, e.g. https://petermolnar.net/elephant-bathing-pool-xixiangchi-monastery/
- Jonny Barnes does two things. If the post simply has co-ordinates, these are included in
datatags, and a text representation derived from OpenStreetMap’s Nominatim service is displayed. The first example of this is from 2014-01-08. This is marked up with h-adr microformats. If there is an existing venue, then this is added to the note with a map and marked up with h-card microformats. The first time this was done was 2016-10-05. See https://jonnybarnes.uk/notes/CB and https://jonnybarnes.uk/notes/Bs
- Markup / microformats
- Data exchange
- Location Services
- Venues database
- Open Source
- Atlas - APIs for looking up timezone information, geocoding, weather information, and generating static maps
How to determine the location of a microformat
To accommodate various different location use-cases, there are multiple places within a microformat structure where location data can be placed. Given a microformat, to determine it’s location:
- create a stack of property maps where location data might be found, in order of priority
- for each potential location property, search the stack for a valid property value
In more detail (pseudocode):
- given a microformat structure mf, to find the location it represents:
- let location-sources be a list of microformats, containing the following, in this order:
- if mf has a location property which is a microformat, that value
- if mf has an adr property which is a microformat, that value
- if mf has a geo property:
- if the geo property is a microformat, that value
- else if the geo property is a string, parse it as a geo: URL and append a derived microformat containing the properties of the geo: URL: latitude+longitude if they’re both present, and altitude if it was present
- for each of the following location properties, search the property map stack in order of priority for a valid value. As soon as one is found, consider that the value. If none are found, the microformat does not have this property
Location information may also contain indication about motion, e.g. a person at a location, but in motion, by some method. Such information in practice includes things like:
- velocity (perhaps with a specific motion vector in 2 or 3 dimensions)
- mode of motion / transport (e.g. walking, running, bicycling, driving, stationary)
Location in Notes discusses some of the issues in adding a location to a note.
The two most common visual elements in presenting location are a textual description of the location and/or a map.
There is an issue of specificity. With all of the details possible in a address, relevancy can be reduced if you add in all the possible details.
For example, to use the site of IWC Cambridge...
The Ray and Maria Stata Center, 32 Massachusetts Institute of Technology, Vassar Street, MIT, Cambridge, Middlesex County, Massachusetts, USA, 02139-4309
The most common textual description is merely the locality, region, and country....Cambridge, Massachusetts, USA. The country is often omitted if it is the same as the individual's usual country.
From a Microformats point of view, once a location has a name(The Ray and Maria Stata Center, for example), it goes from an address to a venue(and a h-adr to a h-card).
The utility of displaying coordinates is debatable. While having them available can be useful...for example, to allow location to be identified on a map, they do not, by themselves, enhance human conception of a where a person is.
Beware of IP Mapping
If you use "IP Mapping" to autogenerate or autosuggest a location for your posts, beware that may give you really bad artificial precision, thus implying you were somewhere you were not, e.g as illustrated by this article:
- 2016-04-10 How an internet mapping glitch turned a random Kansas farm into a digital hell
- 2016-04-12 Update: This is the new digital center of the United States