On 16-5-2010 17:26, Steve Bennett wrote:
> http://wiki.openstreetmap.org/wiki/User:Stevage/tagsupport
[...]
> * Harder than it sounds - almost every source file had changed in a
> way that broke my program.
You still have some (new) issues with the mapnik stylesheet. These might
take some extra code to detect. For instance, you show
railway=spur-siding-yard
as a tag that's rendered by mapnik. In reality, this is stylesheet
internal code, built by the SQL query, to collapse railway=rail +
service=* (recommended tags) and railway=spur, railway=siding,
railway=spur (TIGER import tags) into a single element for mapnik to
handle in the rule which renders this element:
SQL:
case when railway in ('spur','siding')
or (railway='rail' and service in ('spur','siding','yard'))
then 'spur-siding-yard'::text else railway end as railway
Mapnik:
<Filter>[railway]='siding-spur-yard'</Filter>
Processing the data in this way using SQL is much easier (and more
readable IMO) than writing filters like this:
<Filter>[railway]='spur' or [railway]='siding' or [railway]='yard' or
([railway]='rail' and ([service]='spur' or [service]='siding' or
[service]='yard'))</Filter>
Especially when you take into account there also is a bridge variant to
handle.
So you might want to be on the lookout for things like this when
updating your list. Having this internal spur-siding-yard tag in your
list might give people the wrong idea.
--
Lennard
_______________________________________________
Tagging mailing list
Tagging@openstreetmap.org
http://lists.openstreetmap.org/listinfo/tagging
