improve feature-as-marker rendering

[tyrasd]

Under some circumstances the “render small features with marker” feature can be quite annoying. Typical examples are route and boundary relations.

A few ideas to improve the current situation:

• make this disable-able on a per-query basis.
• make this configurable via mapcss on a per-feature basis (MapCSS?)
• introduce a more clever automatic mode that doesn't show markers for parts of relations that are connected to a larger graph (which itself is not small)

//edit: here's a relevant code line for hooking into this: https://github.com/tyrasd/overpass-turbo/blob/master/js/overpass.js#L500

[Klumbumbus]

"make this disable-able on a per-query basis."
+1
Look at the following example: http://overpass-turbo.eu/s/2R3 It shows all streets with lane=* in the city Chemnitz. When you disable "small features as pois" in the settings and compare, you see, that it looks much better and the context is much better represented without these pois. This example is also linked on the osm wiki page of Chemnitz. I would like to integrate in the link, that "small feature as pois" is disabled.

[tyrasd]

As of a97a885, this is possible within mapcss in overpass turbo. Example:

{{style:

way {
  render: native;
}

}}

The new (overpass turbo specific) mapcss statment render accepts three values: auto is the previous behavior to automatically collapse small features to point markers (if not disabled by the user in the settings), native is to render the features always in their native geometry (i.e. never collapse them to points), and point renders all features as points at their centroid position (very similar to using out center; in the overpass QL query).