[OSM-talk] CLC2000

[Frederik Ramm]

Hi,

> > why is this an issue? i would assume the link has to appear whenever
> > some of their data is displayed on screen? setting a tag to some
> > value, that then triggers a link to display at bottom-right should not
> > be too much of an issue. or is it some non-technical issue?
> 
> I take it you're volunteering to write the code to track changes
> to tags and update a database that maps bounding boxes to attribution
> strings and then allows a set of strings to be retrieved on the fly
> to display over the slippy map as you move it?

That would give you attribution and tiles that can be out of sync. The
attribution strings would have to be collected the moment features are
put on a tile. If you are, for some reason, displaying an old tile
of an area where special attribution data has been added in the mean
time, then you would not want that attribution to appear - only after
the tile has been re-rendered.
 
> What do you propose to do when zoomed out to show the whole world
> and there are three hundred attribution strings to display by the
> way?

I guess one would have to keep track of attribution for each pixel,
like a separate colour channel (red=..., green=..., blue=...,
attribution=...). So attribution gets overwritten if another feature
is drawn on top (no need to attribute something you don't show!).

"This little red pixel over there provided by MASSGIS".

Not volunteering, just grinning ;-)

Bye
Frederik

-- 
Frederik Ramm  ##  eMail frederik at remote.org  ##  N49°00.09' E008°23.33'