[GraphHopper] Routing has gaps

[Peter]

Hi,

there is a simplification going on at import time:
hopper.setWayPointMaxDistance or via config: osmreader.wayPointMaxDistance

and additionally at query time:
setSimplifyRequest(true/false) or with more detail:
"douglas.minprecision" as ghRequest hint.

The defaults should be good enough and e.g. it will be avoided at query
time for desktop and mobile usage. See the GraphHopper class.

Kind Regards,
Peter.


On 05.08.2014 08:42, Timothy Lehner wrote:
>
> What is the best way to suppress the Douglas-Peucker filter?
> If I am using the routing in one of my java applications, and I open
> it using:
>
> hopper = new GraphHopper().
> hopper.setInMemory(true);        
> hopper.setOSMFile(osmFile);
>         
> // where to store graphhopper files?
>         
> hopper.setGraphHopperLocation(graphFolder);        
> hopper.setEncodingManager(new EncodingManager("car"));
>                 
> // now this can take minutes if it imports or a few seconds for loading
> // of course this is dependent on the area you import        
> hopper.importOrLoad();
>
>
> Do I need to stop the map getting simplified before this? That is to
> say, should this setting be changed BEFORE the contents of graphFolder
> are generated? (should I re-generate the graph?)
>
> It is vital that I don't lose any information on the customised .osm
> maps that I give, the nodes all need to be accounted for. Luckilly I
> am not doing large scale routing (city - scale only) so I think any
> performance hits this takes should be manageable. Please advise where
> to go next / what to read to better familiarise myself with GraphHopper
>
> Many thanks!
> Tim
>
>
> On 4 August 2014 17:08, Nop <ekkehart at gmx.de <mailto:ekkehart at gmx.de>>
> wrote:
>
>
>     Hi!
>
>     As Timothy said, the result is simplified by default. Most likely
>     those points were removed, as additional points along a straigt
>     line are not needed.
>
>     So I think everything is working fine. If you want ALL points, you
>     need to disable the Douglas-Peucker or set the tolerance to a very
>     small value.
>
>
>     bye
>                         Nop
>
>
>     Am 04.08.2014 16:38, schrieb Timothy Lehner:
>
>         Hello All,
>
>         Sorry for the confusion, I'll try to be clearer.
>
>         I have an open street map with a section that may look like this:
>
>
>         ​
>         I want to travel along the green path. When routing, the route is
>         returned as a list of co-ordinate points.
>
>         For the stretch of road with the circles, the route says I
>         should travel
>         from the co-ordinate of the green circle, to that of the blue
>         circle,
>         however it has missed out the three nodes in between (red).
>
>         As a result I cannot traverse the route, as I see no way to
>         travel from
>         the green circle, directly to the blue circle, I must travel
>         via the red
>         circles which have been omitted.
>
>         I was wondering if there was a way to have the route returned
>         detailing
>         every node that needs to be visited, and in the order it needs
>         visiting,
>         (so instead of getting 2 points, here I'd expect to get 5)
>
>         Does this make things clearer?
>
>         Many thanks,
>
>         Tim
>         ​
>
>
>         On 4 August 2014 15:20, Jan Torben Heuer <jan at komoot.de
>         <mailto:jan at komoot.de>
>         <mailto:jan at komoot.de <mailto:jan at komoot.de>>> wrote:
>
>
>             Am 04.08.2014 um 15:22 schrieb Timothy Lehner
>         <tim at accelogress.com <mailto:tim at accelogress.com>
>             <mailto:tim at accelogress.com <mailto:tim at accelogress.com>>>:
>
>
>                 For example, if my OpenStreetMap has a few close
>             packed nodes, the
>                 route calulcated will have maybe two latLong points.
>             The lat long
>                 points of the nodes in between are missed.
>
>
>             Not sure what „close packed nodes“ are but:
>             - There is a maximum accuracy (10e-6?) due to packing the
>             coordinates into integer values.
>             - There is a default douglas peucker hat simplifies
>         geometries.
>
>             Maybe one of it is the reason.
>
>             Ja
>

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