Hi,

I am a new user and this is my first attempt at creating some dynamic content for GE. I have made a dynamic overlay of the high resolution images of Sweden from Eniro (the major on-line telephone directory company in Sweden).

• Enable the attached network link.
  
• Zoom in to some spot in Sweden where resolution is poor.
  
• Wait a few seconds after the map has stopped moving and you should get a higher resolution overlay fetched from Eniros servers.
  

Caveat: It is kind of slow, it often takes 3-5 seconds for the overlay to appear. I know what the problem is and I am working on it... Also, due to how the bounding box from Google Earth works, the quality is best if viewed from straight up. If viewed at an angle, the resolution gets optimized for stuff far away, resulting in bad aliasing of things close by.

Caveat2: I have not asked Eniro for permission to do this...

Comments welcome!

Update: I have now implemented my own coordinate conversion so I hope it will be slightly faster than before from now on.

--Jonas

Awesome work!
I have been thinking of doing this myself but never got around to it.
From what I can remember they use a different coordinate system than GE. Correct? How did you do the translation? I looked at some math page that explained it but it looked pretty complex to me. Great job. It fits perfectly.
I started a little with Hitta.se's imagery but I didn't have access to a server so my effort was WAY worse than yours. My post


Have you looked at the new features in kml 2.1 with regions. It might help to make your stuff even better.

Hi, thanks for the praise!

Yes, Eniro uses RT90 and GE uses WGS84 (I think) so yes, you have to convert. It is, as you say, a bit complicated. More so since RT90 is two dimesional. Anyway, I cheated. I actually call Lantm�teriets conversion server to do it for me. That whats makes it a bit slow though, so I am now looking into rolling my own after all.

I loked a little into regions, but Eniro is nice enough to provide progressive resolution themselves so there is not a lot of gain. It might help in the case of viewing stuff from an angle though, but on the other hand it would result in a lot more calls to Eniros servers which they might not appreciate...

--Jonas

Hi Jonas,

Congrats to a great dynamic link.

I started myself on this but fell on the conversion, as Adam did. I was thinking a conversion matrix and interpolation. It was rather complex, since I started on the Swedish grid to lat/long conversion as well. At the time I didn't know that Eniro acctually had lat/long as well...

One nice addition to your overlay would be to include the regular street map as well, not only the satellit data. Maybe you can consider that, hint hint...

Now I just wish you could work out something with Eniro so it can stay.

/Magnus

Hi, thanks!

Are you saying that you can get the images from Eniro based on Lat-Long instead of RT90? I did not know that. How?

About the map: I'm not sure how useful it would be since it would cover the imagery. You could make it semi transparent I guess. I find the standard "Roads" overlay to be quite sufficient and detailed enough for my purposes and it overlays the images nicely.

Still, if it turns out to be a common demand, I might look into it.

--Jonas

very well done jonas!

welcome to the community!

as my country mainly in low res i thought to ask you if you could offer something like that for hungary?

thanks!

g

Jonas,

I guess one person can't make it a common demand. I agree that the GE road layer nicely align with your data, often even better than the GE satellit data! What I was after was the data in the Eniro maps about places, buildings and so forth, that you don't have in the road or cities/villages layer. Eniro is outstandning when it comes to finding small places in the country side as well, that's what I'm after...

/Magnus

Well, that would require you to point me to a server that provides high res imagery of Hungary at progressive scale and information on how to call it. And me finding time for it.

So, I'm sad to say, most likely not.

--Jonas

Regarding Eniro and lat-long:

Under the map to the left it stats both, if you zoom in on Gamla Stan in Stockholm it says:

Koordinater f�r kartbildens centrumpunkt:
WGS84 Lat/Long: N 59� 19' 30.28" E 18� 4' 13.82"
RT90: X=6580502, Y=1628955

Not sure, but I saw somewhere that you can call the maps using the lat-long instead of the XY from the Swedish grid. Then maybe you don't have to make the conversion from RT90 to WGS84 either? But maybe this was before the new Ajax support with click to zoom and drag the map to move around?

/Magnus

OK, first of all I have now implemented my own coordinate conversion (if you guys missed the update of the original post) using a direct Gauss-Kruger projection. It should have the same precision as the external server I used before and should also be a little bit faster (I think most of the time is spent waiting for Eniro to deliver the image anyway). Please let me know otherwise.

Regarding other layers from Eniro. I took a quick look at it but it is much more complicated now since they launched the new more AJAXy version with drag and stuff so I could not figure out how to do it on the spot. If I get a little more time some day I might make a more serious attempt.

--Jonas