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Posts: 1,245 | Thanked: 421 times | Joined on Dec 2005
#201
Originally Posted by jaska k View Post
Some promblems when using WMS.

...

Any help or additionad documentation?
Honestly, I don't know much about WMS and how to best utilize it with Maemo Mapper. I do know that I've had problems where the graphics library would crash (with a seg fault) given "image files" that were actually HTML files, as might occur, for example, if a WMS server returned an error instead of a graphics file.

Normally (e.g. with OpenStreetMap, Google Maps, or other non-WMS repositories), errors are returned to Maemo Mapper via an HTTP error code (like 404 if the map doesn't exist). This is fine, because Maemo Mapper can detect this is draw a blank tile instead (although it will retry a few times, too). But WMS servers generally return an HTML page instead. If libpng tries to open that HTML page, sometimes it crashes.

If your WMS server allows you to specify a (safer) mechanism by which it can return errors, then I'd recommend using that feature. Otherwise, you'll have to try and limit yourself to areas of the world that don't produce an error.

And if everywhere is producing an error, check the HTML files themselves (there may be many zero-sized files, but there should be at least one non-zero-length file, too), and see if it provides any insight for why you're getting the error.

If you need to reset Maemo Mapper so that you can tweak the settings (because it crashes every time you start), then run the following command from the command line:

gconftool-2 -u /apps/maemo/maemo-mapper/repositories

This will clear your repositories list and reset it to the default (OpenStreetMap).
 
Posts: 197 | Thanked: 4 times | Joined on Jan 2007
#202
Hope Gnuite sees this question. Don't know if it's been asked and answered yet already.

My wife's car has GPS built-in. It shows the name of the street you are currently on at the bottom of the map on the screen. It also displays the name of the street that is to be your next turn. Is it possible to make MM do that?

thanks,
Neil
 
Posts: 18 | Thanked: 0 times | Joined on May 2006
#203
Originally Posted by gnuite View Post

If your WMS server allows you to specify a (safer) mechanism by which it can return errors, then I'd recommend using that feature. Otherwise, you'll have to try and limit yourself to areas of the world that don't produce an error.
Ok, I can try to use EXCEPTIONS=INIMAGE parameters, WMS server returns then error message as an image. Does it matter if I use for exampe png, png24 or jpeg image format? The Server I use is MapServer, and it is working very well with PC-clients like OpenLayers and ka-Map.

Should I use BBOX=%.6f,%.6f,%.6f,%.6f or BBOX=%.2f,%.2f,%.2f,%.2f with epsg:3067?

More information about 3067:
http://ocean.csl.co.uk/experimental/...ected&server=1
 
Posts: 18 | Thanked: 0 times | Joined on May 2006
#204
I made some "wiresharking" and the query is ok, at least when using BBOX=%.2f,%.2f,%.2f,%.2f.

Actually It seems to be something wrong, when I try to save my repository to internal mmc2 memory card on N800.

I'm able to save repository to mmc1, but not mmc2.

/dev/mmcblk1p1 120.0M 5.2M 114.8M 4% /media/mmc1
/dev/mmcblk0p1 995.1M 693.4M 301.8M 70% /media/mmc2

I have not noticed that other programs has problems with writing to internal mmc2 device.

Also some reprojection problems exists with WMS-service and MM when using epsg:3067, see screenshots:

http://www.kolumbus.fi/evis/mm/screenshot00.png
http://www.kolumbus.fi/evis/mm/screenshot01.png

Last edited by jaska k; 2007-04-02 at 12:20.
 
gnuite's Avatar
Posts: 1,245 | Thanked: 421 times | Joined on Dec 2005
#205
Originally Posted by nspeer View Post
My wife's car has GPS built-in. It shows the name of the street you are currently on at the bottom of the map on the screen. It also displays the name of the street that is to be your next turn. Is it possible to make MM do that?
Maemo Mapper can't show the name of the street you are on, because it doesn't actually have any street data (e.g. Navtech). Maemo Mapper only has bitmap data and the data that comes from your GPS receiver (i.e. latitude, longitude, speed, heading, etc.). So it can plot your location on a bitmap, but it can't "read" that bitmap to interpret which road you're on (or near).

As for displaying "the name of the street that is to be your next turn", the routes that you download (via the "Download Route" dialog) will usually include "waypoints" that, as you get closer to them, will cause a popup message to appear instructing you what to do next (e.g. "Turn left at Main Street. Go 2.6 miles.").
 
gnuite's Avatar
Posts: 1,245 | Thanked: 421 times | Joined on Dec 2005
#206
Originally Posted by jaska k View Post
Ok, I can try to use EXCEPTIONS=INIMAGE parameters, WMS server returns then error message as an image. Does it matter if I use for exampe png, png24 or jpeg image format? The Server I use is MapServer, and it is working very well with PC-clients like OpenLayers and ka-Map.
png, png24, and jpeg are all fine. Any image format understood by gdk-pixbuf should work (since that's what maemo-mapper uses).

Originally Posted by jaska k View Post
Should I use BBOX=%.6f,%.6f,%.6f,%.6f or BBOX=%.2f,%.2f,%.2f,%.2f with epsg:3067?
If you're familiar with C and/or printf, you'd understand the differences between the two. Both should work, but %.2f will be less accurate, so I'd use %.6f.

(Basically, %.2f means to format a floating point number such that it has at most 2 digits after the decimal point. %.6f means 6 digits.)
 
Posts: 18 | Thanked: 0 times | Joined on May 2006
#207
Originally Posted by gnuite View Post
If you're familiar with C and/or printf, you'd understand the differences between the two. Both should work, but %.2f will be less accurate, so I'd use %.6f.
Ok, thanks for clarifying this.

WMS-connetion is now working, but results are...hm...something I did not expect.

This is an example map I get when using OpenLayers client on PC, the figure of Finland when using epsg:3067:
http://www.kolumbus.fi/evis/mm/finland_3067_ok.png

And this is what I get with MaemoMapper:
http://www.kolumbus.fi/evis/mm/finla...067_NOT_OK.png

Could this be a problem between MaemoMapper and Proj? Or should I just change some parameters somewhere?

Oh, I just found this from http://hoohol.ath.cx/public/index.ph...eMM-Extensions

"Tiles don't seem to fit exactly, what can I do?

Not much, sorry. In this case the projection is sufficiently different from the mercator projection and one would need real warping for a fix. Lower zoom levels usually decrease the errors. (For warping look at gdal)"

If this is true, which epsg code correspods mercator projection that Maemo Mapper uses? I can use gdal and proj on server side and hopefully create MM compatible WMS-service.

Last edited by jaska k; 2007-04-02 at 18:53.
 
gnuite's Avatar
Posts: 1,245 | Thanked: 421 times | Joined on Dec 2005
#208
Originally Posted by jaska k View Post
"Tiles don't seem to fit exactly, what can I do?

Not much, sorry. In this case the projection is sufficiently different from the mercator projection and one would need real warping for a fix. Lower zoom levels usually decrease the errors. (For warping look at gdal)"

If this is true, which epsg code correspods mercator projection that Maemo Mapper uses? I can use gdal and proj on server side and hopefully create MM compatible WMS-service.
I don't know anything about EPSG codes... Maemo Mapper uses the same mercator projection that Google Maps and Virtual Earth use, so it's not an uncommon projection - just one that WMS services generally don't use, I guess...
 
Posts: 18 | Thanked: 0 times | Joined on May 2006
#209
Originally Posted by gnuite View Post
I don't know anything about EPSG codes... Maemo Mapper uses the same mercator projection that Google Maps and Virtual Earth use, so it's not an uncommon projection - just one that WMS services generally don't use, I guess...
Ok and Thanks!

Maybe I try later on "self made EPSG" on a server side. Just googled:

<54004> +proj=merc +lat_ts=0 +lon_0=0 +k=1.000000 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m no_defs <>

http://lists.osgeo.org/pipermail/web...er/000154.html
 
Posts: 18 | Thanked: 0 times | Joined on May 2006
#210
Originally Posted by jaska k View Post
<54004> +proj=merc +lat_ts=0 +lon_0=0 +k=1.000000 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m no_defs <>
I got things to work pretty well with previous parameters, just adding them to epsg file on the client and server side. Of course, server requires some additonal reconfiguration to support it.
 
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