I opened a similar thread in october. The origining fact was a sidewalk having a stair, where the other sidewalk had a ramp. I was suggested to map the sidewalk as a separate object. Yours, José.
El 10/12/2017 20:32, "Nick Bolten" <[email protected]> escribió: > > the basic rendering issue where streets already collide with buildings > > The renderer can always be updated to accommodate any issues with showing > where sidewalks exist. This is a situation of having more information > available for display, and how to organize it, which isn't a bad thing. For > example, you could put `footway=sidewalk` ways at a lower z-level and have > basically zero impact on street rendering. > > > where do I put the crossings other than make them up? > > All crossings are made-up, but some have markings that make it easier. > Where you put them depends on local laws and mapping considerations, but at > least having them connect around every intersection is good practice. > F> A pedestrian can cross the road anywhere and will not want a route > that does not allow that most basic of concepts. > > This varies geographically quite a bit, and there are very few routes that > would be improved by adding this consideration. Or, in other words, how > often do real routes need someone to cross at arbitrary locations, with > basically zero metadata to assist with safety / mobility infrastructure? > Examples: > > 1) Your origin and destination are very close together and you have no > mobility preferences except 'walking'. In this case, routing and sidewalks > are pointless, just draw a line from A to B. Several routers make that > interpretation already. > 2) There are several 'shortcuts' along the optimal path, such as alleys, > and one might expect that the router would keep having you go out of the > way to use intersections. Alleys would naturally be connected to streets > and intersect with sidewalks, so these paths *will* be followed so long as > the router allows short trips on streets/driveways (most do). > 3) There exist common entrances to parks / other footways that involve > crossing the street. In this case, it would of course make sense to add a > crossing way. > > Finally, tagging streets with `sidewalk=*` has these same issues. In order > for routing to actually use the information to figure out how > infrastructure is connected, it has to make an expanded graph that maps > sidewalks and how they're connected, and you're back to any potential > issues with mapping sidewalks as separate ways, but you now have > lower-quality information to work with. The ability to "cross the street > anywhere" doesn't really exist in most routers, because they're really just > treating you like a car that moves slower, and crossing (and the sidewalk, > typically) doesn't exist at all in that paradigm. > > On Sun, Dec 10, 2017 at 10:46 AM Philip Barnes <[email protected]> > wrote: > >> On Sun, 2017-12-10 at 18:25 +0000, Nick Bolten wrote: >> >> The downside of using `wheelchair=no` is that there are many conditions >> that will prevent some, but not all, wheelchair users from using the >> infrastructure. For example: some wheelchair users don't care about curb >> ramp info at all because they're comfortable finding driveways and going in >> the street (`kerb=raised` does not imply `wheelchair=no`), while others >> absolutely require proper infrastructure (most powered wheelchair users, >> `kerb=raised` implies `wheelchair=no`). I recommend tagging specific, >> on-the-ground conditions that can be interpreted later, like `kerb`, >> `barrier`, `width`, `surface`. >> >> Another thing is that you probably want this info to be immediately >> useful, but I'm not aware of any existing routers that can use sidewalk=* >> subtags, as the sidewalk=* on a street model has to be expanded to a new >> graph (and the vast majority of routers don't do that). OpenTripPlanner is >> attempting to develop this, but it's unreleased. That doesn't mean you >> shouldn't tag, but it's a segue for my next recommendation: consider >> mapping sidewalks as separate footways. More or less, you describe >> sidewalks as `highway=footway` `footway=sidewalk`, connect them via >> `highway=footway` `footway=crossing` ways, and ensure that those crossings >> intersect and share a node with streets. While this involves more ways, it >> makes it much easier to organize and use the kinds of subtags you're >> interested in using, and can be used directly in most routers. For example, >> you wouldn't have to make an executive decision about `sidewalk:width` vs >> `width:sidewalk` - just use the widely-documented `width` tag. >> >> >> >> Mapping as separate ways can cause many issues, the basic rendering issue >> where streets already collide with buildings, plus where do I put the >> crossings other than make them up? >> >> A pedestrian can cross the road anywhere and will not want a route that >> does not allow that most basic of concepts. >> >> Phil (trigpoint) >> _______________________________________________ >> Tagging mailing list >> [email protected] >> https://lists.openstreetmap.org/listinfo/tagging >> > > _______________________________________________ > Tagging mailing list > [email protected] > https://lists.openstreetmap.org/listinfo/tagging > >
_______________________________________________ Tagging mailing list [email protected] https://lists.openstreetmap.org/listinfo/tagging
