LocalData / localdata-mobile-web

LocalData mobile collection app
http://localdata.com/
BSD 3-Clause "New" or "Revised" License
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Show satellite to the max available zoom and no more #144

Open prashtx opened 10 years ago

prashtx commented 10 years ago

We should be able to use the bing maps metadata to determine how far in we should zoom. That will help for the random areas where imagery is unavailable at z19.

prashtx commented 9 years ago

The bing maps metadata mostly specifies detailed attribution for various bounding boxes at various zoom levels. There is attribution information available even when no imagery exists. We might need to hardcode tile ranges that exist at z19.

prashtx commented 9 years ago

It looks like we can query metadata for specific points at a specific zoom level: http://msdn.microsoft.com/en-us/library/ff701716.aspx We should avoid a super chatty TileLayer, though. We can probably query for z19 availability if we've moved more than some distance from the last check. Then we'll probably need a TileLayer subclass that chooses between Bing aerial+road and our Mapbox streets layer based on the metadata and zoom level.

182 gives us a simple switch from aerial to streets when we go past zoom 19. That should cover us for the main areas of use.