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

[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 quite useful as a guide. Obviously I didn't do any intricate 
journey calculations based on it, but as a ball park figure, it came in use.

Could it be reinstated for the higher level zooms, >11 maybe?

Cheers
Dave F.