Re: [OSM-talk] How inaccurate was the mapnik distance/scale marker?

2010-02-24 Thread Richard Weait
On Wed, Feb 24, 2010 at 8:42 AM, Egil Hjelmeland wrote: > Dave F. wrote: >> So one of the mapnik guys could implement it quite easily then? >> > I don't think it is related to mapnik. It is the javascript code served > by the web-site that wraps up the map rendered by mapnik, osmarender or > what

Re: [OSM-talk] How inaccurate was the mapnik distance/scale marker?

2010-02-24 Thread Egil Hjelmeland
Dave F. wrote: > > Excuse my ignorance, are you saying that it's 2x inaccurate at all > zoom levels? > At lattitude 60: yes. > So one of the mapnik guys could implement it quite easily then? > I don't think it is related to mapnik. It is the javascript code served by the web-site that wraps up

Re: [OSM-talk] How inaccurate was the mapnik distance/scale marker?

2010-02-24 Thread Dave F.
Hi Thanks for your replies Egil Hjelmeland wrote: > I assume you are referring to the OpenLayers based slippy map at > openstreetmap.org? The Openlayers 2.8 ScaleLine class has the the > problem that it does not handle that the map-scale is not constant > accoss the map. The slippy map uses m

Re: [OSM-talk] How inaccurate was the mapnik distance/scale marker?

2010-02-23 Thread Egil Hjelmeland
I assume you are referring to the OpenLayers based slippy map at openstreetmap.org? The Openlayers 2.8 ScaleLine class has the the problem that it does not handle that the map-scale is not constant accoss the map. The slippy map uses mercators projection, where the scale increases with 1/cos(la

[OSM-talk] How inaccurate was the mapnik distance/scale marker?

2010-02-23 Thread Dave F.
Hi There used to be a distance indicator graphic in the bottom left of the map. I believe it was removed because it was inaccurate due to the curvature of the Earth. I can understand the point at low zoom levels, but at say, zoom 13, just how inaccurate, percentage wise, is it? I found it quit