Re: [OSM-talk] Two different ways with the same nodes?
2010/2/12 Anthony o...@inbox.org: On Fri, Feb 12, 2010 at 3:34 AM, Shaun McDonald sh...@shaunmcdonald.me.uk wrote: Why not offset the nodes a little to make them easier to work with and be able to see that there is two ways there? Because that would be tagging for the srenderer/s editor. +1 btw: they will always be offset due to our methods, just zoom in closely and you'll discover. IMHO if you know that there's a double-decker bridge you will be cautious, while if you don't even know that there is such a bridge you better shouldn't edit there anyway (because IMHO a minimum knowledge of the area you're mapping should be present) cheers, Martin ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On 12 Feb 2010, at 06:17, ed...@billiau.net wrote: On Thu, Feb 11, 2010 at 4:57 PM, ed...@billiau.net wrote: Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge The ways should not share nodes, because the ways don't intersect. That is exactly why the duplicated nodes should not be merged. They 'appear' to share the same node, because we are not differentiating according to height in the database. Why not offset the nodes a little to make them easier to work with and be able to see that there is two ways there? Shaun ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On Fri, 12 Feb 2010, Shaun McDonald wrote: On 12 Feb 2010, at 06:17, ed...@billiau.net wrote: On Thu, Feb 11, 2010 at 4:57 PM, ed...@billiau.net wrote: Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge The ways should not share nodes, because the ways don't intersect. That is exactly why the duplicated nodes should not be merged. They 'appear' to share the same node, because we are not differentiating according to height in the database. Why not offset the nodes a little to make them easier to work with and be able to see that there is two ways there? Shaun I don't see any problem with your suggestion. We started discussing what would be valid reasons for duplicate nodes which should not be merged. So many of these thoughts are theoretical cases. We have certainly decided that care is required with the duplicate node finding tool, and some brainpower should be applied to see if the nodes are 'duplicates' or simply shared. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On Fri, Feb 12, 2010 at 3:34 AM, Shaun McDonald sh...@shaunmcdonald.me.ukwrote: Why not offset the nodes a little to make them easier to work with and be able to see that there is two ways there? Because that would be tagging for the srenderer/s editor. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Frederik Ramm schrieb: In our neck of the woods, a typical example for two ways sharing the same nodes would be a road with a tram line on/in it. We do not create one way that has both highway=residential and railway=tram (because then, if the way also had a ref=, name=, or oneway=, would that refer to the tram or the street?) - instead we have two ways using the same nodes. Yes, the tram is a good example for sharing nodes. But i forgot to describe this more precisely: this ways are all highways. If you drive by car, a street it is always the same, has the same name and speed. Sometimes it's part of a trunk or a special touristic route, but this can descibed by tags. I personally can't imagine that theres a good reason why highway-ways share the same nodes, but my way of thinking might be wrong. I will accept this and find a solution for my database. Thank's to all for the answers. Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? One example is US TIGER imports at county lines - the same road would appear twice in the data, with one road connecting left to one county, and the other road connecting right to the other county. When cleaning up county TIGER boundary areas, the correct action is to delete one road and connect both left and right roads to the remaining road. It is possible that someone (a bot?) didn't notice duplicate roads and just merged duplicate nodes, resulting in the case illustrated here. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Another common circumstance is if you have two highways that pass through the same town (for example, one runs nominally southeast to northwest, the other runs nominally southwest to northeast). They may well both include the same street that runs west to east, which would be marked as part of both highways for routing purposes, as well as being marked by the street name as well. -- John F. Eldredge -- j...@jfeldredge.com Reserve your right to think, for even to think wrongly is better than not to think at all. -- Hypatia of Alexandria -Original Message- From: ed...@billiau.net Date: Fri, 12 Feb 2010 08:57:05 To: talk@openstreetmap.org Subject: Re: [OSM-talk] Two different ways with the same nodes? Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Hi, John F. Eldredge wrote: Another common circumstance is if you have two highways that pass through the same town (for example, one runs nominally southeast to northwest, the other runs nominally southwest to northeast). They may well both include the same street that runs west to east, which would be marked as part of both highways for routing purposes, as well as being marked by the street name as well. That would be something that definitely should be done with a relation (people often use type=road for this and then stuff ways into that). Also nicely solves the situation that the road might have two different refs at the same time. Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On Thu, Feb 11, 2010 at 4:57 PM, ed...@billiau.net wrote: Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge The ways should not share nodes, because the ways don't intersect. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On Thu, Feb 11, 2010 at 4:57 PM, ed...@billiau.net wrote: Hi, Stefan Pflumm wrote: this ways are all highways. It surely is unusual for two highways sharing the same nodes, and I cannot think of an example where this would make sense. But that doesn't mean there is none; can you give an example? Bye Frederik Double-decker bridge The ways should not share nodes, because the ways don't intersect. That is exactly why the duplicated nodes should not be merged. They 'appear' to share the same node, because we are not differentiating according to height in the database. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
[OSM-talk] Two different ways with the same nodes?
Hello, Is it allowed (or intended) that two different ways share the same edges? For example: there are nodes a, b, c and two ways A, B with: A = (a, b, c) B = (c, b, a) While loading some osm data in a database i realized that there are some ways with this problem, so is this a correct feauture or a mapping error? ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
On Thu, 11 Feb 2010, Stefan Pflumm wrote: While loading some osm data in a database i realized that there are some ways with this problem, so is this a correct feauture or a mapping error? Anything is allowed, anything that does something useful will materialise the individual ways anyway. Now you can wonder if the data representation is efficient from editability and storage perspective. The first I doubt, though the second might pass. Stefan ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Hello, Is it allowed (or intended) that two different ways share the same edges? For example: there are nodes a, b, c and two ways A, B with: A = (a, b, c) B = (c, b, a) While loading some osm data in a database i realized that there are some ways with this problem, so is this a correct feauture or a mapping error? absolutely correct For example where an admin boundary follows the coast one way for the coast one way for the admin boundary if we have joined ways we are getting renderer problems so the au mob have decided to maintain duplicate ways in those circumstances. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
I think that areas that share nodes with other areas and especially with ordinary roads, create a lot of extra work when something has to be edited. I think that every object should stand on it's own, and if there is a relation between the two, well, eh , use a relation. Gert Gremmen - Openstreetmap.nl (alias: cetest) Before printing, think about the environment. -Oorspronkelijk bericht- Van: talk-boun...@openstreetmap.org [mailto:talk-boun...@openstreetmap.org] Namens ed...@billiau.net Verzonden: Thursday, February 11, 2010 5:32 AM Aan: talk@openstreetmap.org Onderwerp: Re: [OSM-talk] Two different ways with the same nodes? Hello, Is it allowed (or intended) that two different ways share the same edges? For example: there are nodes a, b, c and two ways A, B with: A = (a, b, c) B = (c, b, a) While loading some osm data in a database i realized that there are some ways with this problem, so is this a correct feauture or a mapping error? absolutely correct For example where an admin boundary follows the coast one way for the coast one way for the admin boundary if we have joined ways we are getting renderer problems so the au mob have decided to maintain duplicate ways in those circumstances. ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
Re: [OSM-talk] Two different ways with the same nodes?
Hi, ed...@billiau.net wrote: For example where an admin boundary follows the coast one way for the coast one way for the admin boundary This is a somewhat special case; normally, an admin boundary will be backed by a multipolygon relation, and at least hereabouts (.de) we tend to simply stuff the coastline into the admin multipolygon. So you will have *no* extra boundary=adminisdtrative way along the coast - just one single way tagged as coastline, which also happens to be a member of the boundary relation. (People tend to create one landmass relation that goes only up to the coast, and one for the national boundary which includes a 12 mile zone or so, but that's another matter.) In our neck of the woods, a typical example for two ways sharing the same nodes would be a road with a tram line on/in it. We do not create one way that has both highway=residential and railway=tram (because then, if the way also had a ref=, name=, or oneway=, would that refer to the tram or the street?) - instead we have two ways using the same nodes. And to the OP: Das haetten Dir die Leute auf talk-de auch erklaert ;) Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
