OHM/Historical Time Format
Historical Time Format
As opposed to OSM mapping, the OHM makes heavy use of date information to determine at what time the actual feature was present.
- Key:historic is the primary means of identifying 'modern' (currently existing) objects that have an historic significance such as ruins. There are some temporal references within this tag:
- historic:period=old_kingdom that allows the specific feature to be related to an era, event, civilization.
- historic: lifecycle prefix can be prefixed to any key
- date namespace suffix can be added to any key such as name:1835-1965 = St Cakes Primary School
- OpenPastMap wanted to add a epoch that would detail the dates during which this feature existed.
- specifying history of an object through time: Comparison of life cycle concepts
Other open questions
- How should name changes over time be dealt with?
- OHM:PreviousObject / OHM:NextObject ?
- try date namespace
- How should changes in geometry (eg: borders) be dealt with?
- draw different geometries and apply date namespace to tags as appropriate
- How should movement be dealt with?
- Series of different ways, all with different time stamps?
- Should we suggest OHM:OSMObject as a means of linking historical features to their current OSM equivalent object?