2009/8/28 Richard Fairhurst <[email protected]>: > > Peter Childs wrote: >> The Canal way will need to be split at the lock gates, (or in >> some cases where a diversion starts (due to some rivers >> going over weirs) while there is a lock for boats. > > (UK-specific tagging stuff follows) > > Ideally I'd like to discourage people from using a (non-closed) way for > locks where possible. > > It makes dealing with the data vastly harder; doesn't actually give you many > real advantages; and is actively misleading in that it suggests the length > of the way is significant. Given that UK locks have a tolerance measured in > inches, and our mapping doesn't, the length is much better expressed in the > maxlength tag. > > About the one thing to be said for mapping the lock as a way, with lock-gate > nodes at either end, is that you can route a footpath over one of them. > Which is quite nice in a micro-mapping sort of way but so much of an edge > case (99% of footpath crossings are actually on lock bridges) that I don't > see a real issue. > > If there's a _large_ lock - say, those on the Manchester Ship Canal - then > it should really be mapped as an area, not an unclosed way. >
While I agree that a maxlength tag is a good idea. maxlength still needs to be on a way otherwise its saying the max length of the gate which is utter rubbish. Your suggestion is even more complex. a Closed area would not work as you need to map the gates so you would need 4 ways, one for each bank and one for each gate. I have no knowledge of Canals and shipping, so maybe we need an expert on how to map waterways properly. I guess you need two parallel ways for each bank of a river or canal and a third for the river itself right, When I was adding Tenston Lock I did not the banks where not maped only the river so there was no clue to river width. Oh sorry a river is a series of Area (he frowns) What event happens at the joins are they completely arbitratory. Peter. _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
