It would be interesting to be able to support history of a particular map/view, at least with timed "snapshots". This would probably be fairly easy to implement for SQL based storage. The idea is that the user would define a limited area, a particular zoom level and an interval.
On init, all tiles in the selected area are copied to a new time-lapse table. After each period, find all tiles in main map that either have no previous entry in the time-lapse table, or where the last updated timestamp is higher than the last seen tile in the time-lapse table and the hash code is different, and insert all such tiles into the time-lapse table with an increased snapshot-id or such.
It should be doable to write a query that does the copying "automatically" (let the DB do it for us), and I think it should be doable to make a query that returns a set of the latest tiles for a specific snapshot. Getting the latest version of a specific tile position for a certain snapshot would definitely be trivial, and perhaps what would be needed anyway depending on how the viewer is implemented.
It would be interesting to be able to support history of a particular map/view, at least with timed "snapshots". This would probably be fairly easy to implement for SQL based storage. The idea is that the user would define a limited area, a particular zoom level and an interval.
On init, all tiles in the selected area are copied to a new time-lapse table. After each period, find all tiles in main map that either have no previous entry in the time-lapse table, or where the last updated timestamp is higher than the last seen tile in the time-lapse table and the hash code is different, and insert all such tiles into the time-lapse table with an increased snapshot-id or such.
It should be doable to write a query that does the copying "automatically" (let the DB do it for us), and I think it should be doable to make a query that returns a set of the latest tiles for a specific snapshot. Getting the latest version of a specific tile position for a certain snapshot would definitely be trivial, and perhaps what would be needed anyway depending on how the viewer is implemented.