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lostinpsp
November 7th, 2007, 07:38
Hi everyone, second post here.

I have been able to get Map This working from reading these forums and have made my own map. Its pretty big about 500mb's and works fine.

I then created a POI interest file with all the Suburbs for the map. These worked fine but I can not search for these POI's interests it just shows them on the map as pictures.

I then converted the POI file to a Geodata file with GDML, loaded up Map This and tried to do an address search. I only entered the postcode as 2170 which is an australian postcode and hit the start button and it returned an error saying it could not be found.

Is this the way to create a Geo Data file?

I just want to be able to search by postcode or suburb for some where in a map and be able to find it.

I know Geo Data is hard to come by for Australians but was after some advice as to how to get this going?

Any help appreciated.

Nieko
November 7th, 2007, 08:42
I then created a POI interest file with all the Suburbs for the map. These worked fine but I can not search for these POI's interests it just shows them on the map as pictures.


You can search through POI files by pressing Circle in the POI list instead of Cross.




I then converted the POI file to a Geodata file with GDML, loaded up Map This and tried to do an address search. I only entered the postcode as 2170 which is an australian postcode and hit the start button and it returned an error saying it could not be found.

I found working with geodata isn't as easy as it seems at first. It seems you'll only get results through geodata if you supply at least a street name, and then possibly also city name, post code, etc.




I just want to be able to search by postcode or suburb for some where in a map and be able to find it.


If the list is not too big (few thousand post codes is still fine), I'd suggest just using POI search functionality instead.

Geodata in MapThis is usually split up per post code and city, making it easier and faster to access huge files. Geodata for the Netherlands consists of 820.000 streets e.g. :).

lostinpsp
November 7th, 2007, 21:46
Okay, thanks heaps for that. I did the circle thing and it worked. Took me straight to the suburb correctly. WOW! Can you plot a journey from where you are currently located to that POI from within Map This or do you need to use the mark function?

Further to that I am wondering would it be possible to use a POI file to look up an individual address? Google maps can find an address so I assume there using a KML file. Could that not be extracted converted to CSV / POI then we can do street address look ups without Geo Data?

I know it seems easy written down but that is ultimately what I would like to be able to do with Map This.

Nieko
November 8th, 2007, 09:10
Okay, thanks heaps for that. I did the circle thing and it worked. Took me straight to the suburb correctly. WOW! Can you plot a journey from where you are currently located to that POI from within Map This or do you need to use the mark function?

By default it draws a line from where you currently are to the POI file you found (try moving the cursor). By pressing Circle you can add segments. If you want the route to be calculated, you'll need GMDL or http://getroute.nieko.net/.



Further to that I am wondering would it be possible to use a POI file to look up an individual address? Google maps can find an address so I assume there using a KML file. Could that not be extracted converted to CSV / POI then we can do street address look ups without Geo Data?

Yes it could. But seeing that the Netherlands already have 820k+ streets, you would get millions of street numbers. POI search would then become extremely slow. That's when geodata comes in handy, it splices up the data by post code and city first, so when you supply that as well when searching, results are found a lot quicker.

Of course you can simply calculate a route from point A to point A with GMDL or http://getroute.nieko.net/, giving you the exact location of a specific address.

ndrew2505
November 9th, 2007, 00:57
so whenever you create the geodata file where does it go? i think i successfully created it i just need to know where it goes to make sure. :)

nvm i got it :)

niteloner
November 10th, 2007, 16:55
can anyone give me a guide to making my own geodata or a link to how geodata is being compiled? Thanks!

Nieko
November 10th, 2007, 18:12
GMDL supports creating geodata from CSV files. If you want to know the specific header bytes etc., you could scour the GMDL source or read through the Perl scripts I made for Dutch geodata (http://stuff.nieko.net/psp/mapthis/geodata/process.zip).

alo1234
November 11th, 2007, 14:56
Thanks for the instruction Nieko, but that maproom.psu.edu ftp isn't working so I can't get the australia2pts.txt file off them.
Is there anyway to work around that? been searching for those info on google but I don't understand what those search results are haha. And btw how do you run Perl on ur Windows? or are u using Linux haha

Nieko
November 11th, 2007, 15:02
You could make your own australia2pts.txt in MapThis by just creating points around Australia. The idea is that you need a polygon covering the area of geodata you need.

For Windows, you can use ActivePerl (though personally I'm using Perl on Linux).

alo1234
November 11th, 2007, 15:51
Oh okthanks, I have no idea how I could do that lol. I went for a try in GMDL, creating Geodata using that Google semi-auto thingy, its creating segments atm, dunno if I am doin the right things. I'll try Google (manual) later =(

alo1234
November 11th, 2007, 23:43
Using that Google to create the GEODATA seemed to be impossible because it has like 5m queries, and crashed when it reached 30k queries T_T