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Show HN: Valhalla, an open source routing engine

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Re: Show HN: Valhalla, an open source routing engine

#51

A quick question: I have a list of 100+ million points with their geographical distance, but I want to improve it and calculate the "driving distance". How expensive in terms of time/ops would that be? I'm scanning the different subprojects on Github and I think Tyr is the one I need, but I'm not entirely sure..

With Contraction Hierarchies you can get several hundred routes (or distances) per second. If you want to calculate distance matrices you can get a lot faster.

Re: Show HN: Valhalla, an open source routing engine

#52
post #44
post #40

Earlier quoted context omitted.

what are the best ones?

For speedy street routing, the Open Source Routing Machine: http://project-osrm.org/ Like Google's proprietary routing engine, it leverages the scale of local and regional travel (via contraction hierarchies, arterial travel is suited for precomputed cacheing); result: the system can be tuned to give near instantaneous results. OSRM had been led by Dennis Luxen of Mapbox, though he just moved to Apple. The OP (Mapzen…

Just curious: Where did you heard about that Dennis moved to Apple :) ?

Some clarification:

* the process of the route finding is done by Dijkstra or A* or with a preprocessing (CH)

* valhalla does not use CH to my knowledge

* route optimization requires a completely different technique and valhalla does not do this

> "The OP (Mapzen's Valhalla) appears to have a similar approach as OSRM"

no :) ! OSRM is limited to CH (really fast) and valhalla is limited to Dijkstra/A* (really flexible).

Re: Show HN: Valhalla, an open source routing engine

#53
post #44

Earlier quoted context omitted.

For speedy street routing, the Open Source Routing Machine: http://project-osrm.org/ Like Google's proprietary routing engine, it leverages the scale of local and regional travel (via contraction hierarchies, arterial travel is suited for precomputed cacheing); result: the system can be tuned to give near instantaneous results. OSRM had been led by Dennis Luxen of Mapbox, though he just moved to Apple. The OP (Mapzen…

Just curious: Where did you heard about that Dennis moved to Apple :) ? Some clarification: * the process of the route finding is done by Dijkstra or A* or with a preprocessing (CH) * valhalla does not use CH to my knowledge * route optimization requires a completely different technique and valhalla does not do this > "The OP (Mapzen's Valhalla) appears to have a similar approach as OSRM" no :) ! OSRM is limited to C…

@karussell,

For a public source, Dennis Luxen updated his Linkedin profile.

Thanks for adding your knowledge about the internals of Valhalla code.

Re: Show HN: Valhalla, an open source routing engine

#54
post #40

Earlier quoted context omitted.

what are the best ones?

How do you define best? I'm the author of GraphHopper. Easy to setup, fast and flexible. Try it here: https://graphhopper.com/maps/

+1 ...and open source under Apache License 2.0 :)

Re: Show HN: Valhalla, an open source routing engine

#55
post #26

Earlier quoted context omitted.

Glancing at the Valhalla repos, it looks like the MIT license across the board: https://github.com/valhalla ; https://github.com/valhalla/thor/blob/master/COPYING ; https://github.com/valhalla/chef-valhalla/blob/master/LICENS... ; etc... Also, it's not so much that the routing engines are proprietary -- the best ones are not. The underlying databases are the secret sauce.

> The underlying databases are the secret sauce. No, it is not only about the database. Also about algorithms. But a lot about engineering and optimizing.

You make a great point about engineering. The interaction of algorithms/techniques and the database, as well as computational infrastructure and UI/UX, are all significant areas of differentiation. I still disagree about algorithms themselves as a differentiator -- everyone has access to excellent shortest path algorithms already. Other geospatial optimizations (scheduling, circuits, flows, etc) are a different story; as represented by the many scientific disciplines that pursue those problems: operations research, graph theory, network science, location science, etc.

Re: Show HN: Valhalla, an open source routing engine

#56
post #53

Earlier quoted context omitted.

Just curious: Where did you heard about that Dennis moved to Apple :) ? Some clarification: * the process of the route finding is done by Dijkstra or A* or with a preprocessing (CH) * valhalla does not use CH to my knowledge * route optimization requires a completely different technique and valhalla does not do this > "The OP (Mapzen's Valhalla) appears to have a similar approach as OSRM" no :) ! OSRM is limited to C…

@karussell, For a public source, Dennis Luxen updated his Linkedin profile. Thanks for adding your knowledge about the internals of Valhalla code.

ah, easy, thanks :) !
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