[OSM-dev] OSM-Carto style, ported to vector tiles!

[Christoph Hormann]

On Monday 25 July 2016, Rory McCann wrote:
>
> > That however would also mean you would need to remove all the
> >
> > way_area > 0.01*!pixel_width!::real*!pixel_height!::real
> >
> > filters from SQL for z14 - otherwise you get missing geometries at
> > the higher zooms (not a real lot - that limit is about one Mercator
> > square meter at z14 - but when this occurs it would be visible and
> > possibly surprising).
>
> Oops. I will fix that. Do you know of an example of where this
> filtering applies in the normal OSM tileserver? It's helpful to have
> something to compare to?

That filter is primarily for the lower zooms for performance reasons, in 
particular z6-z9.  You should be able to simply remove it for z14 
without negative effects.

> Yes, you can't use SQL to filter different things after z14. You have
> to use CartoCSS filters. A z14 tile needs to have all the data a z19
> tile needs to render.

The problem is not really filtering - this would be simple using 
additional attributes generated from SQL.  The real difficulty is 
geometry processing.

-- 
Christoph Hormann
http://www.imagico.de/