[GraphHopper] Calculating fastest path with A*/Dijkstra with CH disabled

[mythex3cutioner .]

Well, I'm absolutely new to the maps & Android so sorry if I bother you.
I'm trying to manipulate some routing algorithms, basically, 'implement' my
own one but just for presentation purposes.

My final goal's flowchart would look something like this
-The map is loaded and centered on device's coordinates provided by GPS
(can't find .setFocus() on mapsforge, heh;)) (pointA)
-User selects a point on the map, marker is added (pointB)
-Shortest/fastest path is calculated between those two points
-Second point is selected (pointB)
-Then the algorithm runs only inside my Bounding Box

Since I've added manual weights to some of the edges, there should be
different times for calculations, different routes will be selected, etc.

This is what I want to show - what are the differences when you apply
bounding box or put some insane traffic-weight on the edge while running
the same algorithm :)

Best regards


On Sat, Jan 11, 2014 at 5:27 PM, Peter K <peathal at yahoo.de> wrote:

>  > I mean, just simply like this?
>
> No. First not in the method (in some outer scope instead) and second with
> your own limits not with the edge properties. Again: I have no idea what
> you are trying ...
>
> > I saw examples but they imply that I create algorithms object manually
> and I don't want to since
> > I intend to keep the same Graphhopper.java structure (more or less)
> that's very usable with Android.
>
> You can extend the GraphHopper class and overwrite the necessary methods
> to call setEdgeFilter I think.
>
> Regards,
> Peter.
>
>
>
> On Fri, Jan 10, 2014 at 11:23 PM, Peter K <peathal at yahoo.de> wrote:
>
>>  Hey,
>>
>>   >This is called geocoding and not provided by GraphHopper. Although we
>> >have some (closed source) prototype we still recommend other existing
>> >solutions.
>>
>>  Isn't there a way then to somehow manually find which node/edge ID is
>> associated with street name by reading routing data provided from
>> graphopper.sh script? I only need to figure out 5-10 street's names
>> associated with their edge/node ids so that I could manipulate them via
>> hardcoding. I mean, yes, it's that unpractical and basic but that's my goal
>> here :)
>>
>>
>>  yes, sure: loop over all edges! This extremely expensive and error-prone
>> as there are multiple identical named streets even in one city! But you can
>> find the names:
>>
>> EdgeIterator iter = getAllEdges();
>> while (iter.next())
>> {
>>       iter.getName()
>>
>> }
>>
>>  >Where the last option probably would be the simplest one as there is
>> >already a (hidden) method for it in OSMReader called isInBounds or just
>> >use OSM tools like osmosis:
>> >http://wiki.openstreetmap.org/wiki/Osmosis#Extracting_bounding_boxes
>> >
>> >Or do you need to define it per request? What is your usecase?
>>
>>  Yes, my usecase would be to define per request:
>> -First request calculates the fastest path
>> -Point A is moving inside the map (GPS tracking on)
>> -Timer should recalculate path each 30s or so
>>
>>
>>  Ok, but why would you need to find a path in a subgraph - to limit
>> search space? Wouldn't it make more sense to re-compute the whole path
>> (where you could reuse parts of the old result) or if that is too expensive
>> you could re-compute a path in a bounding box leading you back to the
>> original path.
>>
>>
>>
>>  > >* limit the search to only nodes in this area (this is only possible
>> if no CH is used)
>>  > >
>>   > how is this possible to implement?
>>
>>  Will work for none CH only. You'll have to tweak the algorithm to
>> accept only edges which are in the bounds:
>> edgeFilter = new EdgeFilter() {
>>    accept(EdgeIteratorState state) {
>>       base = state.getBaseNode();
>>       adj = state.getAdjNode();
>>       int baseLat = graph.getLatitude(base);
>>       int baseLon = graph.getLatitude(base);
>> ...
>>       return bbox.contains(baseLat, baseLon) || bbox.contains(adjLat,
>> adjLon);
>>    }
>> }
>> dijkstra.setEdgeFilter(edgeFilter);
>>
>> Regards,
>> Peter.
>>
>> _______________________________________________
>> GraphHopper mailing list
>> GraphHopper at openstreetmap.org
>> https://lists.openstreetmap.org/listinfo/graphhopper
>>
>>
>
>
> _______________________________________________
> GraphHopper mailing listGraphHopper at openstreetmap.orghttps://lists.openstreetmap.org/listinfo/graphhopper
>
>
>
> _______________________________________________
> GraphHopper mailing list
> GraphHopper at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/graphhopper
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/graphhopper/attachments/20140111/8305be2b/attachment.html>