[OSM-dev] Screenshots from OpenStreetMap-Carto spot checking

Tom MacWright tom at macwright.org
Thu Dec 20 23:03:18 GMT 2012


Hey,

Last few days Dane & I have been working on optimizing Carto for this case
- try out the 'condense' branch:
https://github.com/mapbox/carto/tree/condense

This requires one small change: in amenity-symbols.mss, change line 82 to

    [power = 'generator'][[generator:source] = 'wind']::power,

Since condense now supports field-field combinations as well as : in field
names.

Anyway, the main result of this work is that the condense branch (on my
machine) brings Carto's processing time from 2.07 seconds to 0.76 seconds,
so about 2.5x faster.

There's more optimization work that could be done, and this work
unfortunately hasn't started to change the XML output to make a more
efficient product for Mapnik to process.

It's still an experimental branch, but should consitute a Carto 0.9.5 when
it hits stability.

Tom

On Wed, Dec 19, 2012 at 5:04 PM, Alex Barth <alex at mapbox.com> wrote:

> Toby / AJ:
>
> I just captured your reports on the issue queue:
>
> https://github.com/gravitystorm/openstreetmap-carto/issues/26
>
> If anyone else has found issues like these, please report them right away
> on the GitHub project:
>
> https://github.com/gravitystorm/openstreetmap-carto/issues
>
> Thanks!
>
> On Dec 19, 2012, at 4:18 PM, AJ Ashton <aj.ashton at gmail.com> wrote:
>
> >
> > On Wed, Dec 19, 2012 at 3:29 PM, Toby Murray <toby.murray at gmail.com>
> wrote:
> > I was doing some poking around yesterday and noticed that county
> > borders (admin_levl=6) aren't being rendered at zoom 9 and 10. But I
> > do recall some confusion on the existing style between ways and
> > relations. I don't remember the details but there was some difference
> > between the zoom level at which ways and relations tagged with
> > admin_level=6 got rendered. Maybe this caused confusion when porting
> > to carto? Easy place to see this difference:
> > http://bl.ocks.org/d/4271706/#9.00/39.4664/-96.9125
> >
> > This seems to be about boundary relation way members being individually
> (and redundantly?) tagged with boundary=administrative. Some of the
> admin_level=6 ways in this area [1] are tagged as boundary=administrative,
> and others are tagless members of boundary relations. If you zoom out, the
> tagless ways disappear at zoom level 10 and below.
> >
> > [1]: http://osm.org/go/T7OwGz3--
> >
> > This commented out section of the stylesheet may be why the CartoCSS
> version is different:
> >
> >
> https://github.com/gravitystorm/openstreetmap-carto/blob/master/admin.mss#L75-L85
> >
> > --
> > AJ Ashton
> > _______________________________________________
> > dev mailing list
> > dev at openstreetmap.org
> > http://lists.openstreetmap.org/listinfo/dev
>
> Alex Barth
> http://twitter.com/lxbarth
> tel (+1) 202 250 3633
>
>
>
>
>
> _______________________________________________
> dev mailing list
> dev at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/dev
>
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