Felix Hartmann schrieb: > I think the main part that has to be done here is that ferries, or > motorails however as well aerialways get connected to the main road > network using lines (routing over polygons is so complicated that no > router will soon master it in a useful way). > > How they are connected should be dependant on the transport mode to use. > Image huge ferries with different, but consistent places to enter. > > We could have > highway=footway & pier=yes (or similar)for pedestrians entering the > ferry (this is actually one of the rare cases I like to see footway and > not path), > highway=service & motorcycle=yes & foot=no & bicycle=yes > highway=service & access=no & motorcar=yes & hgv=yes > > And the ferry route should connect all three. > > Another example would be a cable_car. > We should have highway=footway (or another key) to connect the street > network to the cable_car. If there are steps inside the building, well > then lets add a section highway=steps...... > > > The principle should be no matter what kind of line there is that can be > used somehow, it should be interconnected with all other transport > usable lines. This means that we should also connect railways to roads, > because otherwise no autorouter can calculate routes using busses and > trains (with walking from one to another) for example. Only airports I > would rather just connect by having a relation list to which other > airports you can get from airport XY.
I get to the conclusion that we exactly have two perspectives. First there is the question of how to get from A to B including public means of transport. The other one guides me to the closest parking lot. A cable car for instance has the same quality as an aerialway. But not as highway=footway. The latter is rather like a highway=service. You can use a car. Ok. it might be forbidden but you can. Offering mountain tops and similar things as addresses on your routing topology will blow up the data dramatically. The key to a fast routing is the reduction of data. "Make things as simple as possible, but not simpler" (Einstein). There are some grey zones. I am living in a "highway=pedestrian" connected to a "highway=service", so I decided to take these tags into account but gave them a low priority so the router selects them only if there is no other way. I do agree. Railways, aerialway etc. should be connected to highways. But this should not be expressed by connecting same nodes. Here ramps or links come into play. If you have a closer look at todays OSM-Data railways are in fact connected to streets. But I wonder if you'd like to stop a train by parking your car on a railroad crossing ;-) What about aerialways? Are they connected, too? In the air? A highway=steps would imply you can use your car here. I think we should strictly distinguish between highway and other tags. If I understood the intention correctly then highway is something you can drive on. Even on highway=pedestrian but not on steps. I hope OSM will take these two perspectives into accoung one day. So we can have routable highway tags like highway=railway, highway=ferry, etc. These are much easier to handle (and to tag) than railway=rail + motorcar=yes + amenity= ... and so on. On the other hand we should consider the real world. This of course means we'll need to build topologies on relations or tags like motorcar=yes, railway=rail. Regards Carsten (alias PiMapper) _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
