[Talk-us] Super-relations or not (was: Relation member_roles from Osmosis import)
(sorry for the crossposting, but this really applies globally, as well as for recent discussions on the talk-us list) Ian Dees ian.d...@gmail.com writes: On Thu, Oct 28, 2010 at 9:14 AM, Peter Budny pet...@gatech.edu wrote: Jochen Topf joc...@remote.org writes: On Wed, Oct 27, 2010 at 10:39:38AM +0200, Frank Broniewski wrote: Thats a left-over from the time when relation members were not ordered. Someone in another thread just told me relation members /aren't/ ordered, and that the ordering that, say, JOSM displays is just as a tool to aid the user... not for any semantic purpose. Which is it? http://wiki.openstreetmap.org/wiki/Elements#Relation says The ordering of elements within a relation is persistent. The members are returned in the order specified at upload. Duplicate elements will retain their specified order. Aha. Now that's interesting. To me, this says we really ought to be using super-relations for route relations, rather than a single relation with roles tagged, for 2 reasons: 1) The common way, up to now, for storing routes that alternate between single- and dual-carriageway has been to leave the single-carriageway parts without a role, or with the role north/south. This makes the order of the members of the relation meaningless, since you can't traverse the ways end-to-end in the specified order. This could be solved by adding the single-carriageway sections twice (once with north and once with south), but at that point, why not take the extra 5 seconds and do super-relations? 2) If the direction of a road (e.g. north/south) is indicated by roles, how do you refer to it elsewhere? For example, if you have a destination sign that says it goes to I-75 Northbound, and all of I-75 is in one relation with roles for north and south, how do you refer to just one direction of the road? You can't refer to the whole relation (because that doesn't reflect what the sign says), and there's no clear way to refer to a role of a relation. With super-relations, this isn't a problem... there would be a subrelation that unambiguously refers to just the northbound or southbound part of the road. I really think that super-relations for routes are the way to go... all the methods are really equivalent, but super-relations are easier to deal with programmatically, preserve a little more information, and are not really any more difficult for users/mappers. If anyone has a compelling argument against super-relations, or for single relations, I'd like to hear it. Supporting both seems really pointless, and I think it's about time we picked one or the other so we can develop proper support for route relations and tools to support them moving forward. -- Peter Budny \ Georgia Tech \ CS PhD student \ ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] [OSM-dev] Super-relations or not
Hi, Peter Budny wrote: 1) The common way, up to now, for storing routes that alternate between single- and dual-carriageway has been to leave the single-carriageway parts without a role, or with the role north/south. This makes the order of the members of the relation meaningless, since you can't traverse the ways end-to-end in the specified order. There is no requirement for the order to have meaning; it is just a tool the server offers you, and you can use it or not. The way I view route relations, it is less about traversal and more about simply stating that a certain way belongs to a certain route. The route relation doesn't lose its usefulness if a little bit in the middle is missing. I would simply group all bits together in the route relation, including the dual carriageway pieces, and not worry about roles etc. - this can all be deducted from the oneway tags. This could be solved by adding the single-carriageway sections twice (once with north and once with south) Please no. 2) If the direction of a road (e.g. north/south) is indicated by roles, I recommend not to do that. If anyone has a compelling argument against super-relations, or for single relations, I'd like to hear it. Supporting both seems really pointless No, supporting them both is quite probably the best way forward. You can start with doing a simple relation, and when you find that there's something more complex to it you can still use a super-relation. I always preach that you should write your code such that wherever you expect a way, you also accept a relation that groups a number of ways. If that were done throughout, then a super-relation would just be a normal relation with one or two sub-relations thrown in as required. No need to go up the tree and demand that super-relations exclusively contain relations etc. Bye Frederik -- Frederik Ramm ## eMail frede...@remote.org ## N49°00'09 E008°23'33 ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
[Talk-us] Divided diamond interchanges in the US
I recently stumbled upon an article[1] about the new use of the divided diamond interchange design in the US. It seems that the first one[2] is here[3] in Missouri and as yet unmapped. A second one in the same city is here[4], and it appears that the old interchange hasn’t been mapped either. Aerial photos on Google and Yahoo are both out of date, so I can’t map them myself. Is anyone in that area and able to update these interchanges? —Alex Mauer “hawke” 1. http://www.core77.com/blog/technology/video_visualization_of_a_new_type_of_traffic-improving_intersection_17734.asp 2. http://en.wikipedia.org/wiki/Diverging_diamond_interchange#Use_in_North_America 3. http://www.openstreetmap.org/?lat=37.24975lon=-93.31073zoom=15layers=M 4. http://www.openstreetmap.org/?lat=37.24975lon=-93.31073zoom=15layers=M ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided (sic) diamond interchanges in the US
On Thu, Oct 28, 2010 at 4:27 PM, Alex Mauer ha...@hawkesnest.net wrote: I recently stumbled upon an article[1] about the new use of the divided diamond interchange design in the US. It seems that the first one[2] is here[3] in Missouri and as yet unmapped. A second one in the same city is here[4], and it appears that the old interchange hasn’t been mapped either. It shouldn't be hard to simply 'braid' the two directions and add the necessary curves in the ramps. It won't be precise but it will be accurate. Anyway http://www.modot.mo.gov/springfield/major_projects/Greene/documents/I-44-Route13DDI.pdf has plans for the first one. The second is at US 60 and National Avenue south of downtown Springfield; plans are here: http://www.modot.mo.gov/springfield/major_projects/Stone/documents/NationalatJFRCorrectVersion.pdf There's a third here: http://www.270dorsettpage.com/ ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided diamond interchanges in the US
On Thu, Oct 28, 2010 at 6:16 PM, Mike N. nice...@att.net wrote: Aerial photos on Google and Yahoo are both out of date, so I can’t map them myself. Is anyone in that area and able to update these interchanges? Interesting - the NAIP imagery includes this, so I'll try to get it later tonight if no one else has updated it by then. I've taken care of the new interchange at I-44 N Kansas Expressway since it's in NAIP but none of the others appear to have been constructed after the 2009 NAIP images were taken. Anyone know if there is any newer aerial imagery available? -- Jeff Ollie ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided diamond interchanges in the US
On Thu, Oct 28, 2010 at 7:54 PM, j...@ocjtech.us j...@ocjtech.us wrote: I've taken care of the new interchange at I-44 N Kansas Expressway Are you sure there's no direct ramp from I-44 west to Norton Road like the plans show? You might also want to include the center sidewalk, as it's a rather strange configuration. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided diamond interchanges in the US
On Thu, Oct 28, 2010 at 9:13 PM, j...@ocjtech.us j...@ocjtech.us wrote: On Thu, Oct 28, 2010 at 7:53 PM, Nathan Edgars II nerou...@gmail.com wrote: On Thu, Oct 28, 2010 at 7:54 PM, j...@ocjtech.us j...@ocjtech.us wrote: I've taken care of the new interchange at I-44 N Kansas Expressway Are you sure there's no direct ramp from I-44 west to Norton Road like the plans show? Not from what I could see from NAIP. It looks like it's there but not yet paved on that image; here's a photo showing that it's now open: http://www.flickr.com/photos/riffsyphon1024/4877762571/ You can also barely make out the sidewalks and crossings on the aerial. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided diamond interchanges in the US
On 10/28/2010 03:27 PM, Alex Mauer wrote: I recently stumbled upon an article[1] about the new use of the divided diamond interchange design in the US. It seems that the first one[2] is here[3] in Missouri and as yet unmapped. A second one in the same city is here[4], and it appears that the old interchange hasn’t been mapped either. Aerial photos on Google and Yahoo are both out of date, so I can’t map them myself. Is anyone in that area and able to update these interchanges? Looks like someone got to it already; I might be out that way but it'll probably be the summer before I'm out anywhere near there. signature.asc Description: OpenPGP digital signature ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
[Talk-us] Any interest in Google Code-In?
Hi everyone, At the Google Summer of Code mentors summit this past weekend Google asked us (the organizations that participated in Summer of Code) to also participate in the Google Code-In project. The Code-In project is similar to the Summer of Code but for 13-18 year olds. The tasks are meant to be much smaller: the students are supposed to sign up for one task at a time, they get $100 for every 3 tasks they complete (up to $500). I talked a bit with Carol (the Google woman running the project) who liked me suggestion for putting up a bunch of mapping-related projects. For example, a project could be map 100 restaurants in your area or map all stores in mall X. We would need a small group of OSM regulars to be able to respond to questions from students, write and/or update documentation to make sure students understand how to edit, and verify that the data entered is valid. She also suggested that the students could do things like write or update documentation, community outreach, etc. There are a couple downsides: the time spent reviewing submitted data (think checking for copyright issues, etc.) might be better spent actually mapping and it doesn't appear that the organizations offering projects get anything other than the work from the students (compare to the cash that Google gives organizations for Summer of Code participation). Is anyone interested in thinking of tasks? If so, please respond some time tomorrow as the application for participation is due by this weekend. -Ian ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
Re: [Talk-us] Divided diamond interchanges in the US
A friend of mine found a flickr set from MODOT with more aerial imagery (not rectified but high resolution) http://www.flickr.com/photos/26387...@n06/sets/72157621103069705 This makes it obvious that there is indeed a direct link over to Norton and that it is open as you can see cars driving on it. It is just concrete instead of blacktop like most of the intersection so it is harder to pick out. I have added it. After looking at the flickr pictures I feel that I can pick out the footways well enough from NAIP imagery to trace them as well. It looks to me like the island going across the bridge is intended for pedestrian use as well. Toby On Thu, Oct 28, 2010 at 6:41 PM, Paul Johnson ba...@ursamundi.org wrote: On 10/28/2010 03:27 PM, Alex Mauer wrote: I recently stumbled upon an article[1] about the new use of the divided diamond interchange design in the US. It seems that the first one[2] is here[3] in Missouri and as yet unmapped. A second one in the same city is here[4], and it appears that the old interchange hasn’t been mapped either. Aerial photos on Google and Yahoo are both out of date, so I can’t map them myself. Is anyone in that area and able to update these interchanges? Looks like someone got to it already; I might be out that way but it'll probably be the summer before I'm out anywhere near there. ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us ___ Talk-us mailing list Talk-us@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk-us
