On Feb 5, 2008 2:47 PM, Ben Laenen <[EMAIL PROTECTED]> wrote: > Hi all, and Andy in particular,
Hi Ben. An excellent selection of suggestions - I'll reply to them inline. > as the past weeks went by while entering cycle routes for Belgium into > OSM, I've come across several issues. It's a big mash-up of needed tags > and improvements, so here goes... > > > * Tagging of alternate routes: > > Some routes have shortcuts, or in general alternate ways (e.g. for when > a route is blocked due to the weekly market day, it's possible to > follow another signed route, or sometimes there's an alternative for > cyclists who don't like sandy roads). These routes are generally marked > as a dashed line on most maps I've seen, to make sure it doesn't look > like the main route. I guess a tag as "route_special=alternate" added > to the route relation works for that to make that happen. I don't think > a "route_special=shortcut" is needed, after all, it's just an > alternate. We have ncn= yes / proposed and this could easily be extended to ncn = yes / proposed / connection / alternative / no without adding any more tags. I'm not sure if anyone will care too much about proposed-alternatives being different from proposed-main-routes, but this wouldn't be hard to solve anyway. > * Tagging of connection routes: > > Connection routes are routes which bring you either from one route to > another one, or from a route to an interesting location like a city > center (or the other way around). These routes also need to look > differently on the map. In the maps I've seen they usually do it by > marking them with a different colour, but I understand that may be a > problem with different networks on one map, so maybe a dotted route > perhaps? Anyway, I propose a "route_special=connection" tag for these. See above > * Rendering when different networks (local, regional, national) are on > the same way: > > It's somewhat solved on the highest zoom in the cycle map by having > transparent ways, It's not perfect though :-) > but in lower zooms it gets messy since it's > apparently a random one that "wins" for each section. That's a bug. It's actually deterministic, but I think what you're seeing on some parts is things like the end of the wider line overlapping with a different section. But I haven't sorted it yet. > I've seen two > different approaches on the maps I've seen so far: > - alternate colours: the section are coloured e.g. > red-blue-red-blue-red-blue (but becomes a problem for more than one > network) > - different networks = different line width: this is my personal > favourite solution for this: make national routes wider than regional > ones, which are again wider than local ones. So you can easily show > three routes on one way if needed. You only need to make sure to draw > to thinnest routes last of course :-) This solution also works nicely > with dashed lines like mentioned above. My preference would be to draw the lines side-by-side, but that's what I'll call the "tube map problem" since mapnik can't do that. > * Preferred colour for the route: > > Now let me first say that this isn't for giving all national routes the > colour "green" for example instead of red in country X. I want to use > this to distinguish routes on the same level which can run into each > other. > > I don't know if something similar exists in the UK, but over here it's > needed for our local routes: these aren't really a network, but they're > themed routes which make loops, and those loops overlap each other, > sometimes two or more of them follow the same road for a short > distance. So, when making them all the same colour on a map it becomes > a route cloud in which you can't see the exact loops anymore, and you > have no idea anymore how the routes go. > > Again, this is usually solved by different colour on maps, so that's why > I propose here an "abstract" "preferred_colour=X" tag, where X could be > a number between 0 and 5. The renderer can then choose its palette and > assign colours to them which suit the map and which don't clash with > the colours of other networks (like all shades of blue for local > routes, shades of red for national routes etc). The person entering the > route in OSM then just need to make sure that no two routes of the same > colour overlap. > > The problem of having two different coloured routes of the same network > level on one road is then solved by alternating the two colours on the > shared road. It's common for routes to be distinguished on signs by colour as much as name or reference. I think they should be mapped with signed_colour = yellow, since that makes it clear. Renderers can then know that the colour is important, but still choose to ignore it if they wish (or map the colours to a chosen palette, or keep all the local routes in blue and put little coloured borders on them or similar). Using "signed_colour" clarifies what we mean. > * Route starting points: > > As the title says: this is for points where a route starts (the local > loop routes for example all have a starting point), usually near a > parking, sometimes at a symbolic place after which the route was named. > > For rendering this could be a big dot, together with the name of the > route and a reference if it has one Sounds good. It's along the same lines as the cycle node networks, where a specific point has a particular meaning. > (that also happily solves the > current issue of not seeing the names for those routes which have no > reference numbers) That's a bug. Fixing it will also stop people using ncn_ref=Something-awfully-long-that-isn't-a-reference-really, which suggests the invention of an ncn_name= tag. Cheers, Andy _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
