[OSM-dev] Slippy map way forward -- OpenLayers and/or Mapstraction?

[Joerg Ostertag]

...
> If you are purging the cache when data is updated (1), you need to
> purge all zoom levels.  And if a node is moved or deleted, you
> need to purge the entire area spanned by all connecting line
> segments.  Note that this area has a bounding box completely
> different from the tile's bounding box.  For long line segments,
> this could be many tiles at the deeper zoom levels.  With the

The longest Segment (as of last planet.osm) is 41 Km. 
And as what I remenber; this was an error. 
For a statistic see 
 http://www.ostertag.name/osm/OSM_errors_segment-long.html
 http://www.ostertag.name/osm/OSM_errors_statistics-segments.html
So I don't think we really have problems with these one or two long segments 
in the higher Zoom levels.

BTW: I would suggest restricting the length of a segment to 10Km this way even 
the longest Segments really needed can be inserted and we can circumvent 
problems like this very easily. Or better lets say 0.1 degree (which is 
aproximately 11 Km) because you can much easier check this while entering the 
Data.

-
Joerg