[done] China maps misaligned

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Harm

[done] China maps misaligned

Post by Harm » Wed Oct 08, 2014 2:44 pm

The satellite maps of Beijing are shifted with respect to the streetmaps by about 400m
You can check this e.g. by looking at the Tianmen Square; first in regular Google map, and then in Google satellite view.
Waypoints are only correctly displayed in either one of them.
The shift can be observed exactly by first going to Google Satellite and then to Google Roads layer; this mode displays both at the same time.
The shift is also present with other other satellite maps, like Bing Hybrid map
The shift does not occur in maps of the Netherlands (Eindhoven)
Hope you can fix it, so that I can locate my hotel correctly.

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Re: China maps misaligned

Post by Psyberia-Support » Thu Oct 09, 2014 10:03 am

Hi,
Yes you're right Google Maps (and most map services) are misaligned over China.
This is made on purpose by map providers to stick with China laws, requiring this shift for security issue.
The Google satellite map however is not shifted (so this is the one which is "correct"), leading to erroneous display (see here on the maps website).
What you can do is:
- Use the satellite view, and overlay the OSM roads layer which is not shifted;
- Get from the community maps list the "China Google Satellite" map, which is also shifted and so will matches the other Google Maps (however, it won't match your GPS location when you're there).
Hope it helps,
Best regards
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Guest

Re: China maps misaligned

Post by Guest » Thu Oct 09, 2014 11:00 am

Thanks for the confirmation!
A nice "Chinese" solution to "solve" the security issue, while still enabling the full service of satellite views.
Xie xie.

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Re: China maps misaligned

Post by Psyberia-Support » Thu Oct 09, 2014 12:31 pm

Yes you're right...
I think it may have been a good solution few years ago, when GPS handsets were much less used (GPS handsets for china also have this shift, so you can find your location on a shifted China map), but now with the spread of smart phones and satellite maps, it doesn't make sense any more...
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Re: China maps misaligned

Post by Psyberia-Support » Sun Oct 01, 2017 11:27 am

New versions of AlpineQuest (from 2.0.2) and OfflineMaps (from 2.6b) will correctly re-align maps over china.
If you have an issue with one map on those versions, please let me know.
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