[Talk-GB] invisible

Malcolm Herring malcolm.herring at btinternet.com
Tue Jan 18 22:34:14 GMT 2011

On 18/01/2011 20:30, Graham Jones wrote:
> Hi Folks,
> To reply to the original question, I have had a *_very_* quick go at
> rendering an overlay showing canal infrastructure over the standard OSM
> map rendering.
> The higher zoom level tiles are still generating, but most of it is at
> http://maps.webhop.net/canals.
> It is running on my home server, which is a nice fast computer, but it
> is behind a slow domestic broadband connection, so it will seem rather
> slow to load from the outside world (sorry!).
> It looks like the tile set is going to be about 1GB, so I can probably
> find somewhere to host it faster if people are interested in it.
> This is a very crude rendering - What it does is:
>     * Extracts all data that is tagged waterway=<something>
>     * Draws blue lines where waterway=canal
>     * Draws blue dots where waterway=lock_gate or lock=yes
> If anyone is interested in improving this, the 'about' page contains a
> link to the mapnik xml file (canal1.xml) that I used to render it -
> please feel free to suggest changes, draw little icons to replace my
> stylish blue dots etc.
> If you want to do something with it but are not familiar with mapnik,
> let me know and I can explain how it works (as far as I know - I am no
> expert!).

A good first step. One improvement would be to include ways that have 
both waterway=river AND boat=yes to be blue lined. You would then see 
all those isolated canals and locks all join up into more complete 
networks of navigable waterways.

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