Re: [OSRM-talk] Island hopping
Hi
How can you detect whether there is an intersection at sea or in
the harbour?
If it is an intersection between route=ferry and route=ferry,
it is almost certainly at sea. The only possible exception is
on the port quay itself, but there you should also have an
intersection between route=ferry and natural=coastline. Hence
the proper logic would be something like
if (route == ferry !intersection(natural=coastline)) {
skip_intersections
}
If OSRM doesn't keep track of coastlines,
if (route == ferry
!route=(road/bicycle/foot/hiking/bus/trolleybus/train/tram/mtb/horse/ski/snowmobile/inline_skates))
{
skip_intersections
}
It is a a bit more complex and less safe but still much better
than mid-sea changes of ferry, which are 100% guaranteed to be
wrong.
It sounds easy to build but i'd rather prefer exactly
these types of errors to see whether OSM data is broken.
This depends on the main purpose of OSRM. If it is primarily
intended as a debugging tool for OSM map data, then that is the
correct approach. But if OSRM is primarily intended as a routing
tool, it is more important that it does its job correctly and
does not add its own errors on top of OSM errors.
Dont work around broken data too much - we want to see where
its broken and correct it.
But you would see it anyway. In this case, if OSRM refused
mid-sea changes of ship, you would see a route that only goes
to the entrance of the Piraeus port and then stops there. This
way it would be even easier to identify the OSM error just by
zooming in on the place where the route stops.
Example: start: Rue des Terre-Neuvas, Miquelon-Langlade, end:
the road in Seal Cove about 50 km north-northwest. There is no
route, OSRM fails and the startpoint is moved to the middle of
the sea.
Start like this: http://s8.postimg.org/t3oc1dbrp/miquelon0.png
Click the end on Seal Cove: http://s28.postimg.org/rs7pa9dh9/miquelon1.png
Boom, error. And see, now we found another ferry route that is
broken just where the green pin moved.
Cheers,
Z
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Re: [OSRM-talk] Island hopping
Hi! On 2014-10-14 21:45, Zenon Panoussis wrote: Hi How can you detect whether there is an intersection at sea or in the harbour? If it is an intersection between route=ferry and route=ferry, it is almost certainly at sea. The only possible exception is on the port quay itself, but there you should also have an intersection between route=ferry and natural=coastline. Hence the proper logic would be something like I guess the question is - should there be an *intersection* in the data? - if ferry routes cross each other on the sea, very likely not - if some routes have the first part of a section similar to each other (e.g. they all leave the port in the same way...), then this could be seen as a likely mapping approach, not really a bug in the data. == I guess this is similar to e.g. tram lines sharing the same way for some of their route. So I guess along that thought, OSRM (and other routers?) should consider changing between ferry routes only at ferry terminals, that would render all on-sea changes invalid anyhow. greetings rudolf ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
Re: [OSRM-talk] Island hopping
Are you telling me i need to fix all those 3 Open Source and 1 Commercial app just to fix this issue? I am not telling you to do anything at all. Nor do I see why fixing OSRM would force you to fix any other applications. I simply reported a problem and, trying to be constructive, suggested a solution. If you're not interested, I might just as well save myself the trouble of reporting problems. Z ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
Re: [OSRM-talk] Island hopping
HI, On Tue, Oct 14, 2014 at 04:19:12PM +0200, Zenon Panoussis wrote: Are you telling me i need to fix all those 3 Open Source and 1 Commercial app just to fix this issue? I am not telling you to do anything at all. Nor do I see why fixing OSRM would force you to fix any other applications. I simply reported a problem and, trying to be constructive, suggested a solution. If you're not interested, I might just as well save myself the trouble of reporting problems. It doesnt force me - The point is either: a) We fix the OSM Dataset to be semantically correct with current rulesets we have b) Try to teach each and every OSM Data consuming application how to interprete a very complicated semantically group of exceptions for rare cornercases. 1) If we dont fix all other routing applications besides OSRM the user experience with OSM will be inconsistent (Even more than it is today) and OSM will be blamed. I understand the problem you report and i told you in my very first mail that changing the application in a very rare semantical corner case is not the way i think OSM works and that its much easier and more consistent to fix the data. The Data is broken anyway as it is today as it does not connect to the harbour/shore highways. Fixing the data will fix the user experience disregarding the application the user is using. OSRM is only a small part of the whole OSM ecosystem - There are literally thousands of applications consuming OSM Data. Consuming OSM Data is a hard task anyway - do you recommend making it even harder by construction even more semantically complicated rulesets to be forced on all those consumers? Fix the data as its broken anyway for more use cases than OSRM. Use OSRM to find those bugs in the data and everyone will be happy. Dont try to paint over broken data. Flo 1) Connecting routable ways in OSM means you can choose the direction to any of the participating ways. An exception to this is when there is a turn restriction. -- Florian Lohoff f...@zz.de signature.asc Description: Digital signature ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
