[GraphHopper] Refactoring OSMReader process

[Stuart Adam]

Hi Peter

Ah yeah, That jar is a uk british national grid converter library which I am not sure I can make public at this time.
I will see if I can find an alternate library that I can plugin for that purpose, unless there is already a dependency in the code base that can be used for this.  OSGBCoordinateConvertor is just what I have experience with. 
The graphhopper.sh import process probably won’t work as that still uses the original OSMReader not the alternate OsItnReader.  At the moment I have been using MiniItnGraphUI (which is based on MinGraphUI) as a trigger for importing the data into a graph as obviously it also allows me to visualise it when it completes.  Obviously a ReaderFactory or similar mechanism to switch between Reader implementations based on the supplied file/configuration options would be a reasonable idea. 

Regards
Stuart

Date: Wed, 22 Oct 2014 22:32:09 +0200
From: graphhopper at gmx.de
To: graphhopper at openstreetmap.org
Subject: Re: [GraphHopper] Refactoring OSMReader process


  
    
  
  
    Hi Stuart,

      

      as said in the ticket: this is really great news!

      

      Regarding the problem: did you recreate the graph? In recent
      version I renamed some options - see the changelog:

https://github.com/graphhopper/graphhopper/blob/master/core/files/changelog.txt

      

      Thanks also for pointing out to the sample data, that will be a
      good starting point for others like me to see the progress. How
      would a simple procedure be to get this working? I tried:

      ./graphhopper.sh import Initial/58096-SX9192-2c1.gz

      

      but got: 

      "Could not find artifact
      uk.co.ordnancesurvey.api:OSGBCoordinateConvertor:jar:1.0.3 in
      central"

      

      > This means the parsing process is already 4 stage

      

      Maybe you go via a 'lightweight' database or MapDB instead of
      reparsing? I once wanted to make this happening for OSM but due to
      lack of time I reprioritized:

      

      Regards,

      Peter.

      

      On 22.10.2014 22:00, Stuart Adam wrote:

    
    
      
      As mentioned in comments about #269 I have been
        working on implementing a reader for Ordnance Survey ITN roads
        data.

        

        This has been based off the code of OSMReader and extracting
        common interfaces.

        

        Due to its use of a modified version of the CarFlagEncoder until
        the recent updates I have been able to use a parsed ITN dataset
        as the working graph for an unmodified graphhopper web app. I
        hope to figure out where the incompatibility has arisen with the
        recent changes in the next few days. Error thrown during web app
        start up follows.

        

        INFO: An exception was caught and reported. Message:
        java.lang.IllegalStateException: Encoding does not match:

        Graphhopper config:
        car:com.graphhopper.routing.util.CarFlagEncoder

        Graph: car|speedFactor=5.0|speedBits=5|turnCosts=false,
        dir:examples/os-itn-sample-gh/

        java.lang.IllegalStateException: Couldn't load graph

        

        

        

        the code is available in engaric/graphhopper if anyone is
        interested though it is still in an experimental shape at this
        stage. 

        Currently supported features :-

        

        1) Import of the basic road network

        2) Import of road names

        3) Grade separation.  An interesting feature of the ITN dataset
        is that roads that pass over each other do have the crossing
        point listed as a node, so additional metadata must be parsed to
        separate the links.

        

        

        Work in progress

        1) Partial categorisation of road types to speed.

        2) One Way systems

        

        Work to be done

        1) Restrictions

        2) Conditional Restrictions

        3) Optimisation of the import process

        

        

        ITN is a copyright data set and not available as Ordnance Survey
        opendata.  However a sample file can be download from 

        

https://www.ordnancesurvey.co.uk/docs/sample-data/os-mastermap-itn-layer-sample-data.zip#sample-data-download

        

        The dataset is a Great Britain road coverage appropriate for car
        navigation.

        

        In some aspects the model of ITN can be compared to osm data,
        but in other areas it is modeled very differently.  This means
        the parsing process is already 4 stage rather than the current
        osm preprocess/write 2 phase parse.  Some elements that in osm
        would be modeled on the way elements (from what I can see so
        far) are modeled on separate elements in ITN.

        

        

        Stuart Adam

      
      

      
      

      _______________________________________________
GraphHopper mailing list
GraphHopper at openstreetmap.org
https://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/20141022/44ec2c0f/attachment.html>