[Talk-GB] invisible

Chris Saunter cds at durhamsi.co.uk
Tue Jan 18 13:16:31 GMT 2011

Hi Folks,

> Using transparent overlays is easy - you do not need to do any real time
> processing - just get an image from a server and dispaly it.   Going for
> something cleverer like vector rendering needs a database to give you the
> correct data, then the javascript in the web browser needs to process it and
> display it.   The difficulty is getting a quick enough database response to
> give a nice user experience - this was the subject of another 2010 Google
> Summer of Code Project
> (http://wiki.openstreetmap.org/wiki/Google_Summer_of_Code/2010/AcceptedProjects).

I think client side overlay of features work well to a degree - but
ultimately there is more power in full vector rendering.

My take on the server responsivitity is that vector rendering clients
shouldn't be making full database queeries.

I think that a static (periodically refreshed) 'binary tile'
architecture where the OSM DB is boiled down into tiles designed for
the single purpose of being rendered quickly is the way to go.
Ideally a map viewer can then call upon both the standard bitmap tiles
and the vector tiles and combine them how it chooses.


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