[Cartoweb-users] Newbie: Map data trouble

[Oliver Christen]

Hi Iain

the routing plugin comming with cartoweb will only produce the shortest path 
between two point (though you can add "cost" to segment depending of some 
user criterias)

you will need to extend the existing routing plugin to add some more infos. 
In your case, once the path has been generated, it should be fairly easy to 
get the list of "point of interest" along that path (like church) with a 
geospatial query (like a buffering around each segments of the path)
Then converting all these info into "human speach" shouldnt be much 
difficult either.

the main difficulty i see is probably into having road data that can be 
effectively used with the pgdjkstra algorythm
I see the matter was discussed a few times on the mapserver mailinglist, 
maybe you will have more details about the data preparation.
otherwise, the pgdijkstra readme.txt give most of the infos on what should 
look like the imported data

hope this help

regards,
Oliver

> Okay great thanks for all your help. I'll look through my data. I have 
> noticed a
> more up to date conversion tool so may use that.
>
> My end goal is to produce an extension to the routing plugin that provides 
> route
> descriptions (for small routes only) in natural language. (i.e turn left 
> after
> the church.) So it may be quite an up hill struggle. If you have any
> suggestions, I'd be really happy to hear them. For the time being, thanks 
> alot
> for all your suggestions so far.
>
>
> Iain Adams
>
>
> Quoting Oliver Christen <oliver.christen at camptocamp.com>:
>
>> Hi Iain,
>> well, if you do not know the coordinates of the extremities of the area 
>> your
>>
>> data is covering, maybe try using an extent that cover europe then change
>> the values manually to a smaller area until you get something acceptable.
>>
>> another thing to take into account is when converting your data into
>> shapefiles, be careful about units convertion. Some times ago I had 
>> problems
>>
>> with some shape whose coordinates units were in centimeters instead of
>> meters, hence the data was totally outside of the intended extend and not
>> showing at all.
>>
>> about routing, be sure your data cover the information needed, for 
>> exemple,
>> if you need direction for roads, you will need two segments for each 
>> piece
>> of road. Also all intersection must be nodes and not simple segment
>> overlaping. Things like that, I not a expert in that matter though.
>>
>> There is a tutorial about this, but sadely the page seems to be down at 
>> the
>> time im writing this, maybe try later:
>> http://chris.narx.net/2005/12/14/build-your-own-routing-solution/
>>
>> You can also read the README that comes with the pgdjkstra module in
>> cartoweb:
>> http://www.cartoweb.org/downloads/pgdijkstra/README.txt
>>
>> regards
>> Oliver
>>
>>
>>
>> > Hi,
>> >
>> > Thanks for replying. I did consider that because I was originally using
>> > the maps
>> > from the reg_france data and then I started to use my data which is 
>> > street
>> > level data. In which case I did play a little with the extent. How do I
>> > know
>> > how much to set it to? The scale of my data is approx 1:2,500 i think.
>> >
>> > If my data is in ERSI shape file format it should be read by default
>> > right? I
>> > have imported my data into postgres/postGIS becauase i am hoping to use
>> > the
>> > routing algorithm so i may try creating layers from that. Is this 
>> > harder?
>> >
>> > Thanks
>> >
>> > Iain Adams
>> >
>> > Quoting Oliver Christen <oliver.christen at camptocamp.com>:
>> >
>> >> Hi,
>> >>
>> >> this is only a supposition, but maybe the extend defined in the sample
>> >> project is totally off for your data?
>> >> be sure the mapfile's EXTENT is correct and also be sure there are no
>> >> extent
>> >>
>> >> defined in the myproject.ini or sampleProject.ini
>> >> (mapInfo.initialMapStates.default.location.bbox)
>> >>
>> >> Regards,
>> >> Oliver
>> >>
>> >>
>> >> >
>> >> > Hello there,
>> >> >
>> >> > I am a newbie and have just created a new project. When I use the
>> >> > sample
>> >> > project
>> >> > available all works fine. However when I attempt to use my own data
>> >> > nothing
>> >> > appears.
>> >> >
>> >> > I have changed the layers in the map file and in the layers.ini and
>> >> > myproject.ini but just cant seem to get the data to show anything. I
>> >> > originally
>> >> > got the data as NTF (UK ordnance survey transfer format) and then
>> >> > converted it
>> >> > to shapefiles using ESRI's map manager. The data seems to work on
>> >> > ArcView.
>> >> >
>> >> > Mapfile
>> >> >
>> >> > LAYER
>> >> > NAME "roads"
>> >> > TYPE POLYGON
>> >> > DATA "oslines"
>> >> > #TEMPLATE "ttt"
>> >> > CLASS
>> >> >         NAME "roads"
>> >> > STYLE
>> >> > COLOR 0 0 0
>> >> > END
>> >> > END
>> >> >  END
>> >> >
>> >> > If anyone has any ideas I would really appreciate it.
>> >> > _______________________________________________
>> >> > Cartoweb-users mailing list
>> >> > Cartoweb-users at lists.maptools.org
>> >> > http://lists.maptools.org/mailman/listinfo/cartoweb-users
>> >> >
>> >>
>> >>
>> >
>> >
>> >
>>
>>
>
>
>