[GraphHopper] Fwd: Re: [OSM-dev] Aleksey Karasavov, Introduction, Improve GraphHopper Routeplanner on Android

[Peter]

Hi Aleksey,

> But i will try to implement an ALT algorithm. I start to read papers
related with ALT algorithm.

Only pick this if you like algorithms & reading papers :) !


> Are there some additional requirement to the algorithm like - Ram
consuming, speed etc?

Fast, good routes, flexible algorithm (e.g. on-demand changes possible
like 'shortest' or 'fastest' or 'without steps') and small RAM usage are
important. But impossible to reach them all. So as we already have a
fast algorithm on Android we need a similar fast but more flexible now.


> And what about this  improvement - "Improve the existing App with the
new Mapsforge library". What work must be done ?

Sorry, that is an old description. It should be now: improve existing
app and integrate openscience/vtm map and a geocoding search


> Do I understand correctly that for successful finishing the project I
must do all improvements (in algorithm and android part)  ?

No, you pick one and you can make it as sophisticated as necessary

Regards,
Peter

On 24.03.2015 11:55, Aleksey Karasavov wrote:
> Hi Peter,
>
> thanks for answer
>
> >This is all very complex and you should really only choose this if
> you know you have lots of interests and probably already some
> knowledge e.g. of mobile hardware (RAM or disc layout etc).
>
> Yes I have a lot of interest of this, but i have a little knowledge in
> mobile hardware field.
> But i will try to implement an ALT algorithm. I start to read papers
> related with ALT algorithm.
>
> What are requirements to the mobile hardware -- power consuming, ram etc ?
> Are there some additional requirement to the algorithm like - Ram
> consuming, speed etc?
>
> >The goal is to create a component which is easy to install on Android
> (via apk) and then integrates nicely with Locus, OSMAnd or Oruxmaps
> What will be integ ration ? Like a external module which can do
> searching ?
>
> And what about this  improvement - "Improve the existing App with the
> new Mapsforge library". What work must be done ?
>
> Do I understand correctly that for successful finishing the project I
> must do all improvements (in algorithm and android part)  ?
>
> Kind Regards,
> Aleksey
>
>
>
> -------- Forwarded Message --------
> Subject: 	Re: [OSM-dev] Aleksey Karasavov, Introduction, Improve
> GraphHopper Routeplanner on Android
> Date: 	Sun, 22 Mar 2015 21:00:59 +0100
> From: 	Peter <graphhopper at gmx.de>
> To: 	Aleksey Karasavov <alekseitk at gmail.com>
>
>
>
> Hi Aleksey,
>
> thanks for your interests
>
> > 1.What are requirements to algorithm and data structure ?
>
> Currently we have the Dijkstra and A* algorithms which are relative
> slow and memory hungry, especially on Android. Also we have
> Contraction Hierarchies which is sufficiently fast and uses not much
> memory but it is not that flexible and has other limitations. So there
> are three possibilities:
>
>  1. implementing an algorithm called ALT to speed-up A* or
>  2. improve the graph data structure for mobile usage (more compact,
> better ) or
>  3. an heuristical A* goal directions like 'avoid going off the
> motorroad' when not too close to the goal. I'm not aware of this area
> for research so you'll do most of the research on your own but of
> course we would give good support.
>
> This is all very complex and you should really only choose this if you
> know you have lots of interests and probably already some knowledge
> e.g. of mobile hardware (RAM or disc layout etc).
>
> > 2.What improvements must be done to background offline routing
> server ?  
>
> You could either reuse and port the existing 'web' module to Android
> or you implement this component from scratch. This is a very Android
> specific task where I cannot really help just a bit advise, so you
> need to be sure that you can research etc by yourself. The goal is to
> create a component which is easy to install on Android (via apk) and
> then integrates nicely with Locus, OSMAnd or Oruxmaps. The locus
> developer already has some work for GraphHopper maybe he is willing to
> share this under the Apache License too:
> http://forum.locusmap.eu/index.php?topic=4036.0
>
> Kind Regards,
> Peter
>
>
> On 22.03.2015 19:00, Aleksey Karasavov wrote:
>> Hello,
>>
>> My name is Aleksey Karasavov and I`am second year Computer Science
>> master studying in  Saint Petersburg State Electrotechnical
>> University,Saint Petersburg, Russia.
>>
>> I`am very interesting in project Improve GraphHopper Routeplanner on
>> Android, because i see that I can acquire knowledge in LBS and
>> Android routing.
>> I have experience on Java,Android and good knowledges into algorithms
>> and data structures. I have some experience into LBS development from
>> project http://geo2tag.org/.
>>
>> I have already started reading a documentation and investigation
>> project from repository. I didn't find any bug tracking system where
>> i can find current issues.
>>
>> Give me please more information about improvements which must be
>> done. For example:
>>
>> 1.What are requirements to algorithm and data structure ?
>> 2.What improvements must be done to background offline routing server
>> ?  
>>
>> I hope I`am not to late , because I`am really interestring into this
>> field.
>>
>> --
>> Regards
>> Aleksey Karasavov
>>  
>>
>>
>>
>>
>> _______________________________________________
>> dev mailing list
>> dev at openstreetmap.org
>> https://lists.openstreetmap.org/listinfo/dev
>
>
>
>
>
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