[Tagging] sidewalks and tagging for the renderer

[Colin Smale]

Yes please!

I was also thinking on the lines of documenting implicit tagging:
*    to save mappers time
*    to save space in the database
*    to avoid confusion
*    to allow a single point of maintenance

At a generic "territory" level with some kind of hierarchy please, so 
for example cities can override counties which can override states which 
can override national rules. As traffic rules are made by some kind of 
government, I am sure the current boundary/admin_level stuff can be used 
as a base as long as a true hierarchy can be found (no multiple 
inheritance!)

<defaults territory="uk">
<defaultentry>
<match>
<tag k="highway" v="motorway" />
</match>
<implies>
<tag k="foot" v="no" />
<tag k="maxspeed" v="70 mph" />
<tag k="bicycle" v="no" />
</implies>
</defaultentry>
</defaults>

Technically it doesn't seem that difficult.

Colin

On 13/04/2012 07:27, Stephen Hope wrote:
> The problem with this, is many mappers are not even aware of what 
> implicit assumptions they are making, and hence won't map them. Saying 
> that they should map them won't help.
>
> Do we need a database* of  explicit default settings for different 
> areas, to be used by renderers, routers and other tools as 
> appropriate? Rules like "In Germany, motorway implies foot=no if there 
> is no foot tag on the way". This could also help give sane guesses of 
> defaults for roads that haven't been tagged at all yet.
>
> * either a separate database, or polygons inside OSM with tags, 
> whatever. That's not the point at the moment
>
> Stephen
>
>