Hi, the details are a bit trickier as we do everything very memory efficient.
And if a osm node occurs twice it is a pillar node, otherwise it is a tower node. Kind Regards, Peter On 03.06.2015 21:05, John Zhao wrote: > I go through the logic: > It go through all osmways, and count the occurrence of nodeID. > if nodeID appear only once, it's a pillar node. > otherwise, it's a tower node. > > That's it. Do I miss something? > > > *Best Regards,* > *ZhiQiang ZHAO* > > On Wed, Jun 3, 2015 at 11:55 AM, Peter <[email protected] > <mailto:[email protected]>> wrote: > > Hi, > > there is no separate merging logic (although there was in 0.1 or > something). In OSMReader it is decided when an edge is created and > e.g. OSM ways are splitted if there are barriers or junctions on > the way. So it decides whether an osm nodes will be a tower node > or just a pillar node > > Regards, > Peter > > > On 03.06.2015 20:35, John Zhao wrote: >> Hi Peter, >> >> Could you tell me where is the merging logic? >> That's interesting. >> >> *Best Regards,* >> *ZhiQiang ZHAO* >> >> On Wed, Jun 3, 2015 at 12:09 AM, Peter <[email protected] >> <mailto:[email protected]>> wrote: >> >> Hi Jan, >> >> we do this kind of 'merging' logic already in the import step >> when deciding what should be handled as tower node and what >> is a pillar node. Otherwise you'll need as twice as many RAM >> when copying from one graph to the other. >> >> >> > Have you made a experiment to count the number of 2 degree nodes >> with the equal flags and >> name in OSM? >> > And then we can know how many edges we can save. >> >> Yes, this should be done before implementing it :) >> >> And as the merging logic is currently not 100% optimal, there >> could be some minor savings even when recognizing the >> different street names, but I'm unsure if it is worth the effort. >> >> Issues like #234 or #111 will probably make more difference. >> >> Kind Regards, >> Peter >> >> >> On 02.06.2015 22:35, John Zhao wrote: >>> Hi, >>> >>> AFAIK, there is no this kind of merging logic here. >>> Wait the answer from Peter. >>> Probably you need to implement it by your own. >>> And it's not easy. >>> Maybe can be done before import? >>> What you want, is actually convert a tower node to a pillar >>> node. >>> >>> >>> *Best Regards,* >>> *ZhiQiang ZHAO* >>> >>> On Tue, Jun 2, 2015 at 1:27 PM, Jan Torben Heuer >>> <[email protected] <mailto:[email protected]>> wrote: >>> >>> Hi ZhiQiang ZHAO, >>> >>> Thanks for your quick answer. >>> I have a custom FlagEncoder that imports only very few >>> ways and I don’t need the names. I guess, I have mostly >>> nodes with a degree of two. >>> >>> Jan >>> >>> Am 02.06.2015 um 21:53 schrieb John Zhao >>> <[email protected] <mailto:[email protected]>>: >>> >>>> Hi, >>>> >>>> Have you made a experiment to count the number of 2 >>>> degree nodes with the equal flags and name in OSM? >>>> And then we can know how many edges we can save. >>>> >>>> I doubt this should be not too much for OSM. >>>> >>>> *Best Regards,* >>>> *ZhiQiang ZHAO* >>>> >>>> On Tue, Jun 2, 2015 at 11:59 AM, Jan Torben Heuer >>>> <[email protected] <mailto:[email protected]>> wrote: >>>> >>>> Hi, >>>> >>>> Can Graphhopper merge two ways with equal flags and >>>> name if there is no intersection between them (no >>>> third way connected)? >>>> >>>> I would like to create a very reduces graph with >>>> only few edges. What would be the easiest way to >>>> achieve it? I think I would have to disable the >>>> nameIndex for instance. >>>> >>>> Thanks, >>>> >>>> Jan >>>> >> >
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