-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Gervase Markham wrote: | Dave Stubbs wrote: |> But some of them will be incorrect. And how do I now make a renderer |> that gives the speed limit in the unit it's actually specified? | | We seem to have a choice between: | | 1) Making renderers which need to understand the units they want to | render on the map, and are capable of converting values in a single | standard unit into that rendered unit and rounding appropriately: | 48.28 -> 29.999mph -> "30mph" | | 2) Making renderers which need to understand all possible units anyone | might use, and how to convert them into the units they want to render on | the map (which may or may not be the units encoded). | 50kph -> 31.07mph -> "30mph" | 45mph -> 45mph -> "45mph" | 73000furlongsperfortnight -> 27.16kph -> "28kph"
The complete list of allowed units for speed is: * kph (assumed if there is none specified) * mph That's it. The fact is that the UK and USA use mph, and they are 2 of the most important countries in OSM. For heights and widths etc, the list is: * ft * m km and miles might turn up somewhere, but I can't think where - normally measures of that scale will be directly in the data by calculating great circle distances or whatever. It's really not that much to consider, and it's not that much that actually has to consider it - as others have said, most renderers can just print the information as is to the user, and don't need to convert it. Robert (Jamie) Munro -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHmKy1z+aYVHdncI0RAtSFAKC/ST9Cyx82MeofkvyNRkX4bB06uACg7bth BxtM0ITj+TU63vhBHG0AhOg= =HIqG -----END PGP SIGNATURE----- _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
