Re: [OSRM-talk] Example of restricted access flags for way_function and turn_function
On 1 July 2017 at 20:00, Michael Krasnyk wrote: > Hi Mateusz, > > for turn restrictions you can use > https://wiki.openstreetmap.org/wiki/Relation:restriction OSM tag. > > Here is an example > https://github.com/Project-OSRM/osrm-backend/blob/e2e279bc852cd024aef1ad445a81bad2884902cd/features/car/restrictions.feature#L11-L34 > that is similar to yours with nodes mapping w->A, j->B, e->C, w->D. Michael, The restrictions.feature sample turned exactly what I was looking for. Thanks a lot! Best regards, -- Mateusz Loskot, http://mateusz.loskot.net ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
Re: [OSRM-talk] Example of restricted access flags for way_function and turn_function
Hi Mateusz, for turn restrictions you can use https://wiki.openstreetmap. org/wiki/Relation:restriction OSM tag. Here is an example https://github.com/Project-OSRM/osrm-backend/blob/ e2e279bc852cd024aef1ad445a81bad2884902cd/features/car/ restrictions.feature#L11-L34 that is similar to yours with nodes mapping w->A, j->B, e->C, w->D. Turns that are restricted via restriction relations will not be used to generate edge-based graph edges. Flags source_restricted and target_restricted as pointed by Daniel are used to mark turns to or from restricted or private areas and simply make turn penalty higher but still allow the turn. I don't think that profile tricks to pass information from way_function to turn_function via a Lua context is a good idea, but still can be used as a workaround. But you have to take care about two points: * Lua contexts are in a thread-local storage, so only single-threaded execution with a single context is possible * ExtractionTurn in include/extractor/extraction_turn.hpp does not contain references to ways, so it must be extended Regards, Michael On Sat, Jul 1, 2017 at 6:21 PM, Mateusz Loskot wrote: > Daniel, > > Thanks for the pointers. I'll check them in details. > > So, I understand purpose of turn_function is to tweak penalty based on > restrictions. > > I'm wondering about slightly different use case and I'm trying to > understand which > tool, way_function or turn_function or neither, is the right way to use. > Shortly, in my use case a restriction is related to allowed/disallowed > turn from one link to another. > Let's consider simple network. > > C > | > B---A > | > D > > Let's assume, all links are bidirectional ways. > Node B includes information about turn restriction like so: > - turning from AB link to BD link is disallowed > - turning from AB link to CB link is allowed > > AFAIU, object in turn_function has no context related to B node and > adjecent links to, > eg. calculate artificial high penalty to effectively block AB to BD turn > I'm also not sure there is way to include necessary context details in > object passed to way_function. > > But, perhaps I'm missing some advanced profile tricks here. > So, does processing of such restrictions fit purpose of turn_function at > all? > > One of feasible alternative approaches is to pre-process such network > splitting the B node to B and B-prim > > A - B - C > C - B' - D > > This would effectively disable travelling along A - B - D > > I'll appreciate any comments. > > Best regards, > Mateusz > > > > > On 1 July 2017 at 10:41, Daniel Hofmann wrote: > > You are correct, the way function can set a "restricted" flag per way > (and > > direction), which you can then use in the turn function to put a high > > penalty on turns from/to "restricted" ways. > > > > The general idea is outlined here: > > > > https://www.openstreetmap.org/user/happygo/diary/40564 > > > > Have a look at ExtractionWay, ExtractionTurn and the > EdgeBasedGraphFactory. > > > > Cheers, > > Daniel J H > > > > On Sat, Jul 1, 2017 at 12:08 AM, Mateusz Loskot > wrote: > >> > >> Hi, > >> > >> I'm trying to learn about use of the way_function result flags, > >> forward_restricted and backward_restricted, and their correspondence > >> with turn_function machinery, especially input source_restricted and > >> target_restricted flags. > >> > >> Is there any data and profile example which shoes these in action? > >> > >> I guess, way_function is called first and any of the restriction flags > set > >> here for the link are passed to turn_function. Correct? > >> > >> Disclaimer: I haven't looked into OSRM implementation details yet, > >> which, once grasped, I guess, might be enlightening. > >> > >> Best regards, > >> -- > >> Mateusz Loskot, http://mateusz.loskot.net > > > -- > Mateusz Loskot, http://mateusz.loskot.net > > ___ > OSRM-talk mailing list > OSRM-talk@openstreetmap.org > https://lists.openstreetmap.org/listinfo/osrm-talk > ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
Re: [OSRM-talk] Example of restricted access flags for way_function and turn_function
Daniel, Thanks for the pointers. I'll check them in details. So, I understand purpose of turn_function is to tweak penalty based on restrictions. I'm wondering about slightly different use case and I'm trying to understand which tool, way_function or turn_function or neither, is the right way to use. Shortly, in my use case a restriction is related to allowed/disallowed turn from one link to another. Let's consider simple network. C | B---A | D Let's assume, all links are bidirectional ways. Node B includes information about turn restriction like so: - turning from AB link to BD link is disallowed - turning from AB link to CB link is allowed AFAIU, object in turn_function has no context related to B node and adjecent links to, eg. calculate artificial high penalty to effectively block AB to BD turn I'm also not sure there is way to include necessary context details in object passed to way_function. But, perhaps I'm missing some advanced profile tricks here. So, does processing of such restrictions fit purpose of turn_function at all? One of feasible alternative approaches is to pre-process such network splitting the B node to B and B-prim A - B - C C - B' - D This would effectively disable travelling along A - B - D I'll appreciate any comments. Best regards, Mateusz On 1 July 2017 at 10:41, Daniel Hofmann wrote: > You are correct, the way function can set a "restricted" flag per way (and > direction), which you can then use in the turn function to put a high > penalty on turns from/to "restricted" ways. > > The general idea is outlined here: > > https://www.openstreetmap.org/user/happygo/diary/40564 > > Have a look at ExtractionWay, ExtractionTurn and the EdgeBasedGraphFactory. > > Cheers, > Daniel J H > > On Sat, Jul 1, 2017 at 12:08 AM, Mateusz Loskot wrote: >> >> Hi, >> >> I'm trying to learn about use of the way_function result flags, >> forward_restricted and backward_restricted, and their correspondence >> with turn_function machinery, especially input source_restricted and >> target_restricted flags. >> >> Is there any data and profile example which shoes these in action? >> >> I guess, way_function is called first and any of the restriction flags set >> here for the link are passed to turn_function. Correct? >> >> Disclaimer: I haven't looked into OSRM implementation details yet, >> which, once grasped, I guess, might be enlightening. >> >> Best regards, >> -- >> Mateusz Loskot, http://mateusz.loskot.net -- Mateusz Loskot, http://mateusz.loskot.net ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
Re: [OSRM-talk] Example of restricted access flags for way_function and turn_function
You are correct, the way function can set a "restricted" flag per way (and direction), which you can then use in the turn function to put a high penalty on turns from/to "restricted" ways. The general idea is outlined here: https://www.openstreetmap.org/user/happygo/diary/40564 Have a look at ExtractionWay, ExtractionTurn and the EdgeBasedGraphFactory. Cheers, Daniel J H On Sat, Jul 1, 2017 at 12:08 AM, Mateusz Loskot wrote: > Hi, > > I'm trying to learn about use of the way_function result flags, > forward_restricted and backward_restricted, and their correspondence > with turn_function machinery, especially input source_restricted and > target_restricted flags. > > Is there any data and profile example which shoes these in action? > > I guess, way_function is called first and any of the restriction flags set > here for the link are passed to turn_function. Correct? > > Disclaimer: I haven't looked into OSRM implementation details yet, > which, once grasped, I guess, might be enlightening. > > Best regards, > -- > Mateusz Loskot, http://mateusz.loskot.net > > ___ > OSRM-talk mailing list > OSRM-talk@openstreetmap.org > https://lists.openstreetmap.org/listinfo/osrm-talk > ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
[OSRM-talk] Example of restricted access flags for way_function and turn_function
Hi, I'm trying to learn about use of the way_function result flags, forward_restricted and backward_restricted, and their correspondence with turn_function machinery, especially input source_restricted and target_restricted flags. Is there any data and profile example which shoes these in action? I guess, way_function is called first and any of the restriction flags set here for the link are passed to turn_function. Correct? Disclaimer: I haven't looked into OSRM implementation details yet, which, once grasped, I guess, might be enlightening. Best regards, -- Mateusz Loskot, http://mateusz.loskot.net ___ OSRM-talk mailing list OSRM-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/osrm-talk
